US20080149343A1 - High power umbilicals for electric flowline immersion heating of produced hydrocarbons - Google Patents

Abstract

Methods and apparatus for installing electrically heated composite umbilicals within subsea flowlines containing produced hydrocarbons as immersion heaters to prevent waxes and hydrates from forming within the subsea flowlines that could block the flowlines. The electrically heated composite umbilicals may be installed, or retrofitted, into existing subsea flowlines. Such retrofitted electrically heated composite umbilicals provide an alternative for previously installed, but failed, permanent heating systems. A hydraulic pump installed on the distant end of an electrically heated composite umbilical also provides artificial lift for the produced hydrocarbons. Other electrically heated umbilicals used as immersion heaters are described. Such immersion heater systems may be removed from the well, repaired, and retrofitted into flowlines without removing the flowlines. Near neutrally buoyant electrically heated umbilicals are described which may be installed great distances into flowlines. Different methods of deploying the electrically heated umbilicals are also provided.

Description

PRIORITY FROM U.S. PATENT APPLICATIONS
• The present application is a continuation-in-part (C.I.P.) application of co-pending U.S. patent application Ser. No. 10/800,443, filed on Mar. 14, 2004, that is entitled “Substantially Neutrally Buoyant and Positively Buoyant Electrically Heated Flowlines for Production of Subsea Hydrocarbons”, an entire copy of which is incorporated herein by reference. Ser. No. 10/800,443 was published on Dec. 9, 2004 having Publication Number US 2004/0244982 A1, an entire copy of which is incorporated herein by reference. The Issue Notification states that Ser. No. 10/800,443 will issue on Dec. 25, 2007 as U.S. Pat. No. 7,311,151.
• Ser. No. 10/800,443 is a continuation-in-part (C.I.P.) application of U.S. patent application Ser. No. 10/729,509, filed on Dec. 4, 2003, that is entitled “High Power Umbilicals for Electric Flowline Immersion Heating of Produced Hydrocarbons”, an entire copy of which is incorporated herein by reference. Ser. No. 10/729,509 was published on Jul. 15, 2004 having the Publication Number US 2004/0134662 A1, an entire copy of which is incorporated herein by reference. Ser. No. 10/729,509 issued as U.S. Pat. No. 7,032,658 B2 on the date of Apr. 25, 2006, an entire copy of which is incorporated herein by reference.
• Ser. No. 10/729,509 is a continuation-in-part (C.I.P) application of U.S. patent application Ser. No. 10/223,025, filed Aug. 15, 2002, that is entitled “High Power Umbilicals for Subterranean Electric Drilling Machines and Remotely Operated Vehicles”, an entire copy of which is incorporated herein by reference. Ser. No. 10/223,025 was published on Feb. 20, 2003, having Publication Number US 2003/0034177 A1, an entire copy of which is incorporated herein by reference. Ser. No. 10/223,025 issued as U.S. Pat. No. 6,857,486 B2 on the date of Feb. 22, 2005, an entire copy of which is incorporated herein by reference.
• Applicant claims priority from the above three U.S. patent application Ser. No. 10/800,443, Ser. No. 10/729,509 and Ser. No. 10/223,025.
CROSS-REFERENCES TO RELATED APPLICATIONS
• This application relates to Provisional Patent Application No. 60/313,654 filed on Aug. 19, 2001, that is entitled “Smart Shuttle Systems”, an entire copy of which is incorporated herein by reference.
• This application also relates to Provisional Patent Application No. 60/353,457 filed on Jan. 31, 2002, that is entitled “Additional Smart Shuttle Systems”, an entire copy of which is incorporated herein by reference.
• This application further relates to Provisional Patent Application No. 60/367,638 filed on Mar. 26, 2002, that is entitled “Smart Shuttle Systems and Drilling Systems”, an entire copy of which is incorporated herein by reference.
• And yet further, this application also relates the Provisional Patent Application No. 60/384,964 filed on Jun. 3, 2002, that is entitled “Umbilicals for Well Conveyance Systems and Additional Smart Shuttles and Related Drilling Systems”, an entire copy of which is incorporated herein by reference.
• This application also relates to Provisional Patent Application No. 60/432,045, filed on Dec. 8, 2002, that is entitled “Pump Down Cement Float Valves for Casing Drilling, Pump Down Electrical Umbilicals, and Subterranean Electric Drilling Systems”, an entire copy of which is incorporated herein by reference.
• And yet further, this application also relates to Provisional Patent Application No. 60/448,191, filed on Feb. 18, 2003, that is entitled “Long Immersion Heater Systems”, an entire copy of which is incorporated herein by reference.
• Ser. No. 10/223,025 claimed priority from the above Provisional Patent Application No. 60/313,654, No. 60/353,457, No. 60/367,638 and No. 60/384,964, and applicant claims any relevant priority in the present application.
• Ser. No. 10/729,509 claimed priority from various Provisional Patent Applications, including Provisional Patent Application No. 60/432,045, and 60/448,191, and applicant claims any relevant priority in the present application.
• The present application also relates to Provisional Patent Application No. 60/455,657, filed on Mar. 18, 2003, that is entitled “Four SDCI Application Notes Concerning Subsea Umbilicals and Construction Systems”, an entire copy of which is incorporated herein by reference.
• The present application further relates to Provisional Patent Application No. 60/504,359, filed on Sep. 20, 2003, that is entitled “Additional Disclosure on Long Immersion Heater Systems”, an entire copy of which is incorporated herein by reference.
• The present application also relates to Provisional Patent Application No. 60/523,894, filed on Nov. 20, 2003, that is entitled “More Disclosure on Long Immersion Heater Systems”, an entire copy of which is incorporated herein by reference.
• The present application further relates to Provisional Patent Application No. 60/532,023, filed on Dec. 22, 2003, that is entitled “Neutrally Buoyant Flowlines for Subsea Oil and Gas Production”, an entire copy of which is incorporated herein by reference.
• And yet further, the present application relates to Provisional Patent Application No. 60/535,395, filed on Jan. 10, 2004, that is entitled “Additional Disclosure on Smart Shuttles and Subterranean Electric Drilling Machines”, an entire copy of which is incorporated herein by reference.
• Ser. No. 10/800,443 claimed priority from U.S. Provisional Patent Applications No. 60/455,657, No. 60/504,359, No. 60/523,894, No. 60/532,023, and No. 60/535,395, and applicant claims any relevant priority in the present application.
• Further, the present application relates to Provisional Patent Application No. 60/661,972, filed on Mar. 14, 2005, that is entitled “Electrically Heated Pumping Systems Disposed in Cased Wells, in Risers, and in Flowlines for Immersion Heating of Produced Hydrocarbons”, an entire copy of which is incorporated herein by reference.
• Yet further, the present application relates to Provisional Patent Application No. 60/665,689, filed on Mar. 28, 2005, that is entitled “Automated Monitoring and Control of Electrically Heated Pumping Systems Disposed in Cased Wells, in Risers, and in Flowlines for Immersion Heating of Produced Hydrocarbons”, an entire copy of which is incorporated herein by reference.
• Further, the present application relates to Provisional Patent Application No. 60/669,940, filed on Apr. 9, 2005, that is entitled “Methods and Apparatus to Enhance Performance of Smart Shuttles and Well Locomotives”, an entire copy of which is incorporated herein by reference.
• And further, the present application relates to Provisional Patent Application No. 60/761,183, filed on Jan. 23, 2006, that is entitled “Methods and Apparatus to Pump Wirelines into Cased Wells Which Cause No Reverse Flow”, an entire copy of which is incorporated herein by reference.
• And yet further, the present application relates to Provisional Patent Application No. 60/794,647, filed on Apr. 24, 2006, that is entitled “Downhole DC to AC Converters to Power Downhole AC Electric Motors and Other Methods to Send Power Downhole”, an entire copy of which is incorporated herein by reference.
RELATED U.S. APPLICATIONS
• The following applications are related to this application, but applicant does not claim priority from the following related applications.
• This application relates to Ser. No. 09/375,479, filed Aug. 16, 1999, having the title of “Smart Shuttles to Complete Oil and Gas Wells”, that issued on Feb. 20, 2001, as U.S. Pat. No. 6,189,621 B1, an entire copy of which is incorporated herein by reference.
• This application also relates to application Ser. No. 09/487,197, filed Jan. 19, 2000, having the title of “Closed-Loop System to Complete Oil and Gas Wells”, that issued on Jun. 4, 2002 as U.S. Pat. No. 6,397,946 B1, an entire copy of which is incorporated herein by reference.
• This application also relates to application Ser. No. 10/162,302, filed Jun. 4, 2002, having the title of “Closed-Loop Conveyance Systems for Well Servicing”, that issued as U.S. Pat. No. 6,868,906 B1 on Mar. 22, 2005, an entire copy of which is incorporated herein by reference.
• And this application also relates to application Ser. No. 11/491,408, filed Jul. 22, 2006, having the title of “Methods and Apparatus to Convey Electrical Pumping Systems into Wellbores to Complete Oil and Gas Wells”, an entire copy of which is incorporated herein by reference.
RELATED FOREIGN APPLICATIONS
• And yet further, this application also relates to PCT Application Serial Number PCT/US00/22095, filed Aug. 9, 2000, having the title of “Smart Shuttles to Complete Oil and Gas Wells”, that has International Publication Number WO 01/12946 A1, that has International Publication Date of Feb. 22, 2001, that issued as European Patent No. 1,210,498 B1 on the date of Nov. 28, 2007, an entire copy of which is incorporated herein by reference.
• This application further relates to PCT Patent Application Number PCT/US02/26066 filed on Aug. 16, 2002, entitled “High Power Umbilicals for Subterranean Electric Drilling Machines and Remotely Operated Vehicles”, that has the International Publication Number WO 03/016671 A2, that has International Publication Date of Feb. 27, 2003, that issued as European Patent No. 1,436,482 B1 on the date of Apr. 18, 2007, an entire copy of which is incorporated herein by reference.
• This application further relates to PCT Patent Application Number PCT/US03/38615 filed on Dec. 5, 2003, entitled “High Power Umbilicals for Electric Flowline Immersion Heating of Produced Hydrocarbons”, that has the International Publication Number WO 2004/053935 A2, that has International Publication Date of Jun. 24, 2004, an entire copy of which is incorporated herein by reference.
• This application further relates to PCT Patent Application Number PCT/US2004/008292, filed on Mar. 17, 2004, entitled “Substantially Neutrally Buoyant and Positively Buoyant Electrically Heated Flowlines for Production of Subsea Hydrocarbons”, that has International Publication Number WO 2004/083595 A2 that has International Publication Date of Sep. 30, 2004, an entire copy of which is incorporated herein by reference.
RELATED U.S. DISCLOSURE DOCUMENTS
• This application further relates to disclosure in U.S. Disclosure Document No. 451,044, filed on Feb. 8, 1999, that is entitled ‘RE:—Invention Disclosure—“Drill Bit Having Monitors and Controlled Actuators”’, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 458,978 filed on Jul. 13, 1999 that is entitled in part “RE:—INVENTION DISCLOSURE MAILED Jul. 13, 1999”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 475,681 filed on Jun. 17, 2000 that is entitled in part “ROV Conveyed Smart Shuttle System Deployed by Workover Ship for Subsea Well Completion and Subsea Well Servicing”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 496,050 filed on Jun. 25, 2001 that is entitled in part “SDCI Drilling and Completion Patents and Technology and SDCI Subsea Re-Entry Patents and Technology”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 480,550 filed on Oct. 2, 2000 that is entitled in part “New Draft Figures for New Patent Applications”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 493,141 filed on May 2, 2001 that is entitled in part “Casing Boring Machine with Rotating Casing to Prevent Sticking Using a Rotary Rig”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 492,112 filed on Apr. 12, 2001 that is entitled in part “Smart Shuttle™ Conveyed Drilling Systems”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 495,112 filed on Jun. 11, 2001 that is entitled in part “Liner/Drainhole Drilling Machine”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 494,374 filed on May 26, 2001 that is entitled in part “Continuous Casting Boring Machine”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 495,111 filed on Jun. 11, 2001 that is entitled in part “Synchronous Motor Injector System”, an entire copy of which is incorporated herein by reference.
• And yet further, this application also relates to disclosure in U.S. Disclosure Document No. 497,719 filed on Jul. 27, 2001 that is entitled in part “Many Uses for The Smart Shuttle™ and Well Locomotive™”, an entire copy of which is incorporated herein by reference.
• This application further relates to disclosure in U.S. Disclosure Document No. 498,720 filed on Aug. 17, 2001 that is entitled in part “Electric Motor Powered Rock Drill Bit Having Inner and Outer Counter-Rotating Cutters and Having Expandable/Retractable Outer Cutters to Drill Boreholes into Geological Formations”, an entire copy of which is incorporated herein by reference.
• Still further, this application also relates to disclosure in U.S. Disclosure Document No. 499,136 filed on Aug. 26, 2001, that is entitled in part ‘Commercial System Specification PCP-ESP Power Section for Cased Hole Internal Conveyance “Large Well Locomotives™”’, an entire copy of which is incorporated herein by reference.
• And yet further, this application also relates to disclosure in U.S. Disclosure Document No. 516,982 filed on Aug. 20, 2002, that is entitled “Feedback Control of RPM and Voltage of Surface Supply”, an entire copy of which is incorporated herein by reference.
• And further, this application also relates to disclosure in U.S. Disclosure Document No. 531,687 filed May 18, 2003, that is entitled “Specific Embodiments of Several SDCI Inventions”, an entire copy of which is incorporated herein by reference.
• Further, the present application relates to U.S. Disclosure Document No. 572,723, filed on Mar. 14, 2005, that is entitled “Electrically Heated Pumping Systems Disposed in Cased Wells, in Risers, and in Flowlines for Immersion Heating of Produced Hydrocarbons”, an entire copy of which is incorporated herein by reference.
• Yet further, the present application relates to U.S. Disclosure Document No. 573,813, filed on Mar. 28, 2005, that is entitled “Automated Monitoring and Control of Electrically Heated Pumping Systems Disposed in Cased Wells, in Risers, and in Flowlines for Immersion Heating of Produced Hydrocarbons”, an entire copy of which is incorporated herein by reference.
• Further, the present application relates to U.S. Disclosure Document No. 574,647, filed on Apr. 9, 2005, that is entitled “Methods and Apparatus to Enhance Performance of Smart Shuttles and Well Locomotives”, an entire copy of which is incorporated herein by reference.
• Yet further, the present application relates to U.S. Disclosure Document No. 593,724, filed Jan. 23, 2006, that is entitled “Methods and Apparatus to Pump Wirelines into Cased Wells Which Cause No Reverse Flow”, an entire copy of which is incorporated herein by reference.
• Further, the present application relates to U.S. Disclosure Document No. 595,322, filed Feb. 14, 2006, that is entitled “Additional Methods and Apparatus to Pump Wirelines into Cased Wells Which Cause No Reverse Flow”, an entire copy of which is incorporated herein by reference.
• And further, the present application relates to U.S. Disclosure Document No. 599,602, filed on Apr. 24, 2006, that is entitled “Downhole DC to AC Converters to Power Downhole AC Electric Motors and Other Methods to Send Power Downhole”, an entire copy of which is incorporated herein by reference.
• And finally, the present application relates to the U.S. Disclosure Document that is entitled “Seals for Smart Shuttles” that was mailed to the USPTO on the Date of Dec. 22, 2006 by U.S. Mail, Express Mail Service having ExpressMail Number EO 928 739 065 US, an entire copy of which is incorporated herein by reference.
• Various references are referred to in the above defined U.S. Disclosure Documents. For the purposes herein, the term “reference cited in applicant's U.S. Disclosure Documents” shall mean those particular references that have been explicitly listed and/or defined in any of applicant's above listed U.S. Disclosure Documents and/or in the attachments filed with those U.S. Disclosure Documents. Applicant explicitly includes herein by reference entire copies of each and every “reference cited in applicant's U.S. Disclosure Documents”. To best knowledge of applicant, all copies of U.S. patents that were ordered from commercial sources that were specified in the U.S. Disclosure Documents are in the possession of applicant at the time of the filing of the application herein.
RELATED U.S. TRADEMARKS
• Various references are referred to in the above defined U.S. Disclosure Documents. For the purposes herein, the term “reference cited in applicant's U.S. Disclosure Documents” shall mean those particular references that have been explicitly listed and/or defined in any of applicant's above listed U.S. Disclosure Documents and/or in the attachments filed with those U.S. Disclosure Documents. Applicant explicitly includes herein by reference entire copies of each and every “reference cited in applicant's U.S. Disclosure Documents”. In particular, applicant includes herein by reference entire copies of each and every U.S. patent cited in U.S. Disclosure Document No. 452648, including all its attachments, that was filed on Mar. 5, 1999. To best knowledge of applicant, all copies of U.S. patents that were ordered from commercial sources that were specified in the U.S. Disclosure Documents are in the possession of applicant at the time of the filing of the application herein.
• Applications for U.S. Trademarks have been filed in the USPTO for several terms used in this application. An application for the Trademark “Smart Shuttle™” was filed on Feb. 14, 2001 that is Serial No. 76/213676, an entire copy of which is incorporated herein by reference. The term Smart Shuttle® is now a Registered Trademark. The “Smart Shuttle™” is also called the “Well Locomotive™”. An application for the Trademark “Well Locomotive™” was filed on Feb. 20, 2001 that isSerial Number 76/218211, an entire copy of which is incorporated herein by reference. The term “Well Locomotive” is now a Registered Trademark. An application for the Trademark of “Downhole Rig” was filed on Jun. 11, 2001 that isSerial Number 76/274726, an entire copy of which is incorporated herein by reference. An application for the Trademark “Universal Completion Device™” was filed on Jul. 24, 2001 that isSerial Number 76/293175, an entire copy of which is incorporated herein by reference. An application for the Trademark “Downhole BOP” was filed on Aug. 17, 2001 that isSerial Number 76/305201, an entire copy of which is incorporated herein by reference.
• Accordingly, in view of the Trademark Applications, the term “smart shuttle” will be capitalized as “Smart Shuttle”; the term “well locomotive” will be capitalized as “Well Locomotive”; the term “downhole rig” will be capitalized as “Downhole Rig”; the term “universal completion device” will be capitalized as “Universal Completion Device”; and the term “downhole bop” will be capitalized as “Downhole BOP”.
BACKGROUND OF THE INVENTION
• 1. Field of Invention
• The fundamental field of the invention relates to methods and apparatus that may be used to drill and complete wells at great lateral distances from a drill site. The invention may be used to reach any lateral distance from the surface drill site, from close to the drill site, to a maximum radial distance of at least 20 miles from the surface drill site. This is accomplished by using a near neutrally buoyant umbilical that is attached to a subterranean electric drilling machine. The near neutrally buoyant umbilical is capable of providing up to 320 horsepower to do work at lateral distances of at least 20 miles. This drilling application requires near neutrally buoyant umbilicals capable of providing high power at great distances and high speed data communications to and from the surface. The near neutrally buoyant umbilical reduces the frictional drag of the umbilical within the wellbore. To convey drilling equipment to great distances also requires methods and apparatus to move heavy equipment through pipes at relatively high speeds. Similar high power umbilicals having high speed data communications to and from the surface are also useful for providing power and communications to remotely operated vehicles used for subsea service work in the oil and gas industry.
• Such high power electrically heated composite umbilicals are also useful as immersion heaters to be installed, or retrofitted, into subsea flowlines to prevent the formation of waxes and hydrates and to prevent the blockage of the flowlines. Such retrofitted electrically heated composite umbilicals provide an alternative for previously installed, but failed, permanent heating systems. A hydraulic pump installed on the distant end of an electrically heated composite umbilical also provides artificial lift to the produced hydrocarbons. Other electrically heated umbilicals used as immersion heaters are also described. Such immersion heater systems may be removed from the well, repaired, and retrofitted into flowlines without removing the flowlines. Near neutrally buoyant electrically heated umbilicals are described which may be installed great distances into flowlines. Different methods of deploying the electrically heated umbilicals are also discussed.
• Such high power, electrically heated composite umbilicals that are substantially neutrally buoyant, or positively buoyant, in sea water are also useful as flowlines for producing hydrocarbons from subsea wells.
• 2. Description of the Related Art
• The oil and gas industry does not now have the capability to drill horizontally extreme distances of approximately 20 miles to commercially meet some of the challenges that exist today. Industry extended reach-drilling capability is currently between 6 and 7 miles. Conventional drilling rigs using drill pipe and mud motors at shallow angles have established these conventional records. These wells have pushed conventional drilling technologies close to their practical limit and new methods are required for longer offsets.
• The industry's lack of a 20 mile drilling capability reduces accessibility to oil and gas reserves. Many areas, both onshore and offshore, have no surface access for development drilling. Onshore, this may be due to urban development as is the case in Holland, national parks or other special areas such as the Arctic National Wildlife Refuge (ANWR), or other land uses that are sensitive to surface drilling operations. Offshore, the incentive is to maximize the use of existing structures and infrastructure by replacing expensive flowlines, manifold and trees. Near shore regions as found in the Santa Barbara Channel, and especially where ice may be present such as in the Arctic or near Sakhalin Island, or where migrating whales may limit seasonal operations provide significant incentives for this new 20 mile drilling capability.
• The industry does not have an extreme reach lateral drilling system that is compatible with existing drilling and production infrastructure. If such a system were available, new roads, drill sites, pits, site remediation, permitting, etc. are all avoided in such onshore operations. Offshore, existing host structures will have greatly extended usefulness while reservoirs within 20-mile radii may be developed.
• The industry does not have an extreme reach drilling capability that reduces the risk to the environment. If such a system were available, then operating from drilling and production centers would allow using subsurface access to the reservoirs. There would be no surface flowlines or facilities outside the regional drilling and production center. Extreme reach lateral drilling systems could eliminate the need for many of the flowlines on the ocean bottom in a regional development. However, centralized surface operations with fixed facilities require a paradigm shift in development drilling operations. The well drilling and maintenance equipment would not normally be mobile (except offshore on vessels) and it would normally spend its entire working life from one location.
• Several references are cited below related to the topics of expandable casing, methods to expand tubulars and casings, fabricating composite umbilicals, and well management systems.
• Relevant references to expandable casing includes U.S. Pat. No. 5,667,011, entitled “Method of Creating a Casing in a Borehole”, which issued on Sep. 16, 1997, that is assigned to Shell Oil Company of Houston, Tex., and the following U.S. patents, entire copies of which are incorporated herein by reference:
• U.S. Pat. No. 5,366,012; U.S. Pat. No. 5,348,095; U.S. Pat. No. 5,240,074;
  U.S. Pat. No. 4,716,965; U.S. Pat. No. 4,501,327; U.S. Pat. No. 4,495,997;
  U.S. Pat. No. 3,958,637; U.S. Pat. No. 3,203,451; U.S. Pat. No. 3,172,618;
  U.S. Pat. No. 3,052,298; U.S. Pat. No. 2,447,629; U.S. Pat. No. 2,207,478
• Relevant references to expandable casing also includes U.S. Pat. No. 6,431,282, entitled “Method for Annular Sealing”, which issued on Aug. 13, 2002, that is assigned to Shell Oil Company of Houston, Tex., and the following U.S. patents, entire copies of which are incorporated herein by reference:
• U.S. Pat. No. 6,012,522; U.S. Pat. No. 5,964,288; U.S. Pat. No. 5,875,845;
  U.S. Pat. No. 5,833,001; U.S. Pat. No. 5,794,702; U.S. Pat. No. 5,787,984;
  U.S. Pat. No. 5,718,288; U.S. Pat. No. 5,667,011; U.S. Pat. No. 5,337,823;
  U.S. Pat. No. 3,782,466; U.S. Pat. No. 3,489,220; U.S. Pat. No. 3,363,301;
  U.S. Pat. No. 3,297,092; U.S. Pat. No. 3,191,680; U.S. Pat. No. 3,134,442;
  U.S. Pat. No. 3,126,959; U.S. Pat. No. 2,294,294; U.S. Pat. No. 2,248,028
• Other relevant foreign patent documents related expandable casing include the following, entire copies of which are incorporated herein by reference:
E.P. 0,643,794; W.O. 09,933,763; W.O. 09,923,046;W.O. 09,906,670; W.O. 09,902,818; W.O. 09,703,489;W.O. 09,519,942; W.O. 09,419,574; W.O. 09,409,252;W.O. 09,409,250; W.O. 09,409,249
• Other publications related to expandable casing include the following documents related to Enventure Global Technology of Houston, Tex., entire copies of which are incorporated herein by reference:
(a) Campo, D., et al., “Drilling and Recompletion Applications Using Solid Expandable Tubular Technology”, SPE/IADC 72304 at 2002 SPE/IADC Middle East Drilling Technology Conference and Exhibition, 11 Mar. 2002.(b) Moore, M., et al., “Field Trial Proves Upgrades to Solid Expandable Tubulars”, OTC 14217 at 2002 Offshore Technology Conference, 6-9 May 2002.(c) Grant, T., et al., “Deepwater Expandable Openhole Liner Case Histories Learnings Through Field Applications”, OTC 14218 at 2002 Offshore Technology Conference, 6-9 May 2002.(d) Dupal, K., et al., “Realization of the Mono-Diameter Well: Evolution of a Game-Changing Technology”, OTC 14312 at 2002 Offshore Technology Conference, 6-9 May 2002.(e) Moore, M., et al., “Expandable Linear Hangers: Case Histories”, OTC 14313 at 2002 Offshore Technology Conference, 6-9 May 2002.(f) Nor, N., et al., “Transforming Conventional Wells to Bigbore Completions Using Solid Expandable Tubular Technology”, OTC 14315 at 2002 Offshore Technology Conference, 609 May 2002.(g) Merritt, R., et al., “Well Remediation Using Expandable Cased-Hole Liners—Summary of Case Histories”, Texas Tech University's Southwestern Petroleum Short Course—2002 Conference.(h) Cales, G., et al., “Subsidence Remediation—Extending Well Life Through the Use of Solid Expandable Casing Systems”, AADE 01-NC-HO-24 at March 2001 Conference.(i) Dupal, K., et al., “Solid Expandable Tubular Technology—A Year of Case Histories in the Drilling Environment”, SPE/IADC 67770 at 2001 SPE/IADC Drilling Conference 27 Feb.-1 Mar. 2001.(j) Dupal, K., et al., “Well Design With Expandable Tubulars Reduces Costs and Increases Success in Deepwater Applications”, Deep Offshore Technology, 2002.(k) Daigle, C., et al., “Expandable Tubulars: Field Examples of Application in Well Construction and Remediation”, SPE 62958 at SPE Annual Technical Conference and Exhibition, 1-4 Oct. 2000.(l) Bullock, M., et al., “Using Expandable Solid Tubulars to Solve Well Construction Challenges in Deep Waters and Maturing Properties”, IBP 275 00 at the Rio Oil & Gas Conference, 16-19 Oct. 2000.(m) Mack, A., et al., “In-Situ Expansion of Casing and Tubing—Effect on Mechanical Properties and Resistance to Sulfide Stress Cracking”, NACE 00164 at theNACE Expo Corrosion 2000 Conference, 26-30 Mar. 2000.(n) Lohoefer, C., et al., “Expandable Liner Hanger Provides Cost-Effective Alternative Solution”, IADC/SPE 59151 at 2000 IADC/SPE Drilling Conference, 23-25 Feb. 2000.(o) Filippov, A., et al., “Expandable Tubular Solutions”, SPE 56500 at 1999 SPE Annual Technical Conference and Exhibition, 3-6 Oct. 1999.
• (p) Haut, R., et al., “Meeting Economic Challenge of Deepwater Drilling with Expandable-Tubular Technology”, Deep Offshore Technology Conference, 1999.
(q) Bayfield, M., et al., “Burst and Collapse of a Sealed Multilateral Junction Numerical Simulations”, SPE/IADC 52873 at 1999 SPE/IADC Drilling Conference, 9-11 Mar. 1999.
• Relevant references related to expandable casing also include U.S. Pat. No. 6,354,373, entitled “Expandable Tubing for a Well Bore Hole and Method of Expanding”, which issued on Mar. 12, 2002, that is assigned to the Schlumberger Technology Corporation of Houston, Tex., and the following U.S. patents, entire copies of which are incorporated herein by reference:
• U.S. Pat. No. 6,012,522; U.S. Pat. No. 5,631,557; U.S. Pat. No. 5,494,106;
  U.S. Pat. No. 5,366,012; U.S. Pat. No. 5,348,095; U.S. Pat. No. 5,337,823;
  U.S. Pat. No. 5,200,072; U.S. Pat. No. 5,083,608; U.S. Pat. No. 5,014,779;
  U.S. Pat. No. 4,976,322, U.S. Pat. No. 5,830,109; U.S. Pat. No. 4,716,965;
  U.S. Pat. No. 4,501,327; U.S. Pat. No. 4,495,997; U.S. Pat. No. 4,308,736;
  U.S. Pat. No. 3,948,321; U.S. Pat. No. 3,785,193; U.S. Pat. No. 3,691,624;
  U.S. Pat. No. 3,489,220; U.S. Pat. No. 3,477,506; U.S. Pat. No. 3,364,993;
  U.S. Pat. No. 3,353,599; U.S. Pat. No. 3,326,293; U.S. Pat. No. 3,054,455;
  U.S. Pat. No. 3,028,915; U.S. Pat. No. 2,734,580; U.S. Pat. No. 2,447,629;
  U.S. Pat. No. 2,214,226; U.S. Pat. No. 1,652,650; U.S. Pat. No. 341,327
• Other relevant foreign patent documents related to expandable casing include the following, entire copies of which are incorporated herein by reference:
S.U. 1,747,673; S.U. 1,051,222; W.O. 93/25799
• Relevant references for methods to expand tubulars and casings include U.S. Pat. No. 6,325,148, entitled “Tools and Methods for Use with Expandable Tubulars”, which issued on Dec. 4, 2001, that is assigned to Weatherford/Lamb, Inc. of Houston, Tex., and the following U.S. patents, entire copies of which are incorporated herein by reference:
• U.S. Pat. No. 6,070,671; U.S. Pat. No. 6,029,748; U.S. Pat. No. 5,979,571;
  U.S. Pat. No. 5,960,895; U.S. Pat. No. 5,924,745; U.S. Pat. No. 5,901,789;
  U.S. Pat. No. 5,887,668; U.S. Pat. No. 5,785,120; U.S. Pat. No. 5,706,905;
  U.S. Pat. No. 5,667,011; U.S. Pat. No. 5,636,661; U.S. Pat. No. 5,560,426;
  U.S. Pat. No. 5,553,679; U.S. Pat. No. 5,520,255; U.S. Pat. No. 5,472,057;
  U.S. Pat. No. 5,409,059; U.S. Pat. No. 5,366,012; U.S. Pat. No. 5,348,095;
  U.S. Pat. No. 5,322,127; U.S. Pat. No. 5,307,879; U.S. Pat. No. 5,301,760;
  U.S. Pat. No. 5,271,472; U.S. Pat. No. 5,267,613; U.S. Pat. No. 5,156,209;
  U.S. Pat. No. 5,052,849; U.S. Pat. No. 5,052,483; U.S. Pat. No. 5,014,779;
  U.S. Pat. No. 4,997,320; U.S. Pat. No. 4,976,322; U.S. Pat. No. 4,883,121;
  U.S. Pat. No. 4,866,966; U.S. Pat. No. 4,848,469; U.S. Pat. No. 4,807,704;
  U.S. Pat. No. 4,626,129; U.S. Pat. No. 4,581,617; U.S. Pat. No. 4,567,631;
  U.S. Pat. No. 4,505,612; U.S. Pat. No. 4,505,142; U.S. Pat. No. 4,502,308;
  U.S. Pat. No. 4,487,630; U.S. Pat. No. 4,483,399; U.S. Pat. No. 4,470,280;
  U.S. Pat. No. 4,450,612; U.S. Pat. No. 4,445,201; U.S. Pat. No. 4,414,739;
  U.S. Pat. No. 4,407,150; U.S. Pat. No. 4,387,502; U.S. Pat. No. 4,382,379;
  U.S. Pat. No. 4,362,324; U.S. Pat. No. 4,359,889; U.S. Pat. No. 4,349,050;
  U.S. Pat. No. 4,319,393; U.S. Pat. No. 3,977,076; U.S. Pat. No. 3,948,321;
  U.S. Pat. No. 3,820,370; U.S. Pat. No. 3,785,193; U.S. Pat. No. 3,780,562;
  U.S. Pat. No. 3,776,307; U.S. Pat. No. 3,746,091; U.S. Pat. No. 3,712,376;
  U.S. Pat. No. 3,691,624; U.S. Pat. No. 3,689,113; U.S. Pat. No. 3,669,190;
  U.S. Pat. No. 3,583,200; U.S. Pat. No. 3,489,220; U.S. Pat. No. 3,477,506;
  U.S. Pat. No. 3,354,955; U.S. Pat. No. 3,353,599; U.S. Pat. No. 3,326,293;
  U.S. Pat. No. 3,297,092; U.S. Pat. No. 3,245,471; U.S. Pat. No. 3,203,483;
  U.S. Pat. No. 3,203,451; U.S. Pat. No. 3,195,646; U.S. Pat. No. 3,191,680;
  U.S. Pat. No. 3,191,677; U.S. Pat. No. 3,186,485; U.S. Pat. No. 3,179,168;
  U.S. Pat. No. 3,167,122; U.S. Pat. No. 3,039,530; U.S. Pat. No. 3,028,915;
  U.S. Pat. No. 2,633,374; U.S. Pat. No. 2,627,891; U.S. Pat. No. 2,519,116;
  U.S. Pat. No. 2,499,630; U.S. Pat. No. 2,424,878; U.S. Pat. No. 2,383,214;
  U.S. Pat. No. 2,214,226; U.S. Pat. No. 2,017,451; U.S. Pat. No. 1,981,525;
  U.S. Pat. No. 1,880,218; U.S. Pat. No. 1,301,285; U.S. Pat. No. 988,504
• Other relevant foreign patent documents related to methods to expand tubulars and casings include the following, entire copies of which are incorporated herein by reference:
W.O. 99/23354; W.O. 99/18328; W.O. 99/02818; W.O. 98/00626;W.O. 97/21901; W.O. 94/25655; W.O. 93/24728; W.O. 92/01139G.B. 2329918A; G.B. 2320734A; G.B. 2313860B; G.B. 2216926A;G.B. 1582392; G.B. 1457843; G.B. 1448304; G.B. 1277461;G.B. 997721; G.B. 792886; G.B. 730338;E.P. 0 961 007 A2; E.P. 0 952 305 A1; E.P. WO93/25800;D.E. 4133802C1; D.E. 3213464A1
• Another relevant publication related to methods to expand tubulars and casings includes the following, an entire copy of which is incorporated herein by reference: Metcalfe, P. “Expandable Slotted Tubes Offer Well Design Benefits”, Petroleum Engineer International, vol. 69, No. 10 (October 1996), pp 60-63.
• Relevant references for fabricating composite umbilicals includes U.S. Pat. No. 6,357,485 B2, entitled “Composite Spoolable Tube”, which issued on Mar. 19, 2002, having the inventors of Quigley et al. (hereinafter “Quigley et al.”), that is assigned to the Fiberspar Corporation, an entire copy of which is incorporated herein by reference. Column 7, lines 39-60, of Quigley et al. states the following: ‘P. K. Mallick in the text book entitled Fiber-Reinforced Composites, Materials manufacturing and Design, defines a composite in the following manner: “Fiber-reinforced composite materials consist of fibers of high strength and modulus embedded in or bonded to a matrix with distinct interfaces (boundary) between them. In general, fibers are the principal load arraying [carrying] member, while the surrounding matrix keeps them in the desired location and orientation, acts as a load transfer medium between them, and protects them from environmental damages due to elevated temperatures and humidity, for example.” This definition defines composites as used in this invention with the fibers selected from a variety of available materials including carbon, aramid, and glass and the matrix or resin selected from a variety of available materials including thermoset resin such as epoxy and vinyl ester or thermoplastic resins such as polyetheretherketone (PEEK), polyetherketoneketone (PEKK), nylon, etc. Composite structures are capable of carrying a variety of loads in combination or independently, including tension, compression, pressure, bending, and torsion.’
• Relevant references for fabricating composite umbilicals also include the following U.S. patents, entire copies of which are incorporated herein by reference:
• U.S. Pat. No. 6,286,558; U.S. Pat. No. 6,148,866; U.S. Pat. No. 5,921,285;
  U.S. Pat. No. 6,016,845; U.S. Pat. No. 646,887; U.S. Pat. No. 1,930,285;
  U.S. Pat. No. 2,648,720; U.S. Pat. No. 2,690,769; U.S. Pat. No. 2,725,713;
  U.S. Pat. No. 2,810,424; U.S. Pat. No. 3,116,760; U.S. Pat. No. 3,277,231;
  U.S. Pat. No. 3,334,663; U.S. Pat. No. 3,379,220; U.S. Pat. No. 3,477,474;
  U.S. Pat. No. 3,507,412; U.S. Pat. No. 3,522,413; U.S. Pat. No. 3,554,284;
  U.S. Pat. No. 3,579,402; U.S. Pat. No. 3,604,461; U.S. Pat. No. 3,606,402;
  U.S. Pat. No. 3,692,601; U.S. Pat. No. 3,700,519; U.S. Pat. No. 3,701,489;
  U.S. Pat. No. 3,734,421; U.S. Pat. No. 3,738,637; U.S. Pat. No. 3,740,285;
  U.S. Pat. No. 3,769,127; U.S. Pat. No. 3,783,060; U.S. Pat. No. 3,828,112;
  U.S. Pat. No. 3,856,052; U.S. Pat. No. 3,856,052; U.S. Pat. No. 3,860,742;
  U.S. Pat. No. 3,933,180; U.S. Pat. No. 3,956,051; U.S. Pat. No. 3,957,410;
  U.S. Pat. No. 3,960,629; U.S. RE29,122; U.S. Pat. No. 4,053,343;
  U.S. Pat. No. 4,057,610; U.S. Pat. No. 4,095,865; U.S. Pat. No. 4,108,701;
  U.S. Pat. No. 4,125,423; U.S. Pat. No. 4,133,972; U.S. Pat. No. 4,137,949;
  U.S. Pat. No. 4,139,025; U.S. Pat. No. 4,190,088; U.S. Pat. No. 4,200,126;
  U.S. Pat. No. 4,220,381; U.S. Pat. No. 4,241,763; U.S. Pat. No. 4,248,062;
  U.S. Pat. No. 4,261,390; U.S. Pat. No. 4,303,457; U.S. Pat. No. 4,308,999;
  U.S. Pat. No. 4,336,415; U.S. Pat. No. 4,463,779; U.S. Pat. No. 4,515,737;
  U.S. Pat. No. 4,522,235; U.S. Pat. No. 4,530,379; U.S. Pat. No. 4,556,340;
  U.S. Pat. No. 4,578,675; U.S. Pat. No. 4,627,472; U.S. Pat. No. 4,657,795;
  U.S. Pat. No. 4,681,169; U.S. Pat. No. 4,728,224; U.S. Pat. No. 4,789,007;
  U.S. Pat. No. 4,992,787; U.S. Pat. No. 5,097,870; U.S. Pat. No. 5,170,011;
  U.S. Pat. No. 5,172,765; U.S. Pat. No. 5,176,180; U.S. Pat. No. 5,184,682;
  U.S. Pat. No. 5,209,136; U.S. Pat. No. 5,285,008; U.S. Pat. No. 5,285,204;
  U.S. Pat. No. 5,330,807; U.S. Pat. No. 5,334,801; U.S. Pat. No. 5,348,096;
  U.S. Pat. No. 5,351,752; U.S. Pat. No. 5,428,706; U.S. Pat. No. 5,435,867;
  U.S. Pat. No. 5,443,099; U.S. RE35,081; U.S. Pat. No. 5,469,916;
  U.S. Pat. No. 5,551,484; U.S. Pat. No. 5,730,188; U.S. Pat. No. 5,755,266;
  U.S. Pat. No. 5,828,003; U.S. Pat. No. 5,921,285; U.S. Pat. No. 5,933,945;
  U.S. Pat. No. 5,951,812; U.S. Pat. No. 6,016,845; U.S. Pat. No. 6,148,866;
  U.S. Pat. No. 6,286,558; U.S. Pat. No. 6,004,639; U.S. Pat. No. 6,361,299
• Other relevant foreign patent documents related to fabricating composite umbilicals include the following, entire copies of which are incorporated herein by reference:
DE 4214383; EP 0024512; EP 352148; EP 505815; GB 553,110;GB 2255994; GB 2270099
• Other relevant publications related to fabricating composite umbilicals include the following, entire copies of which are incorporated herein by reference:
(a) Fowler Hampton et al.; “Advanced Composite Tubing Usable”, The American Oil & Gas Reporter, pp. 76-81 (September 1997).
• (b) Fowler Hampton et al.; “Development Update and Applications of an Advanced Composite Spoolable Tubing”, Offshore Technology Conference held in Houston Tex. from 4th to 7th of May 1998, pp. 157-162.
(c) Hahan H. Thomas and Williams G. Jerry; “Compression Failure Mechanisms in Unidirectional Composites”, NASA Technical Memorandum pp 1-42 (August 1984).
• (d) Hansen et al.; “Qualification and Verification of Spoolable High Pressure Composite Service Lines for the Asgard Field Development Project”, paper presented at the 1997 Offshore Technology Conference held in Houston Tex. from 5th to 8th of May 1997, pp. 45-54.
  (e) Haug et al.; “Dynamic Umbilical with Composite Tube (DUCT)”, Paper presented at the 1998 Offshore Technology Conference held in Houston Tex. from 4th to 7th of May, 1998, pp. 699-712.
  (f) Lundberg et al.; “Spin-off Technologies from Development of Continuous Composite Tubing Manufacturing Process”, Paper presented at the 1998 Offshore Technology Conference held in Houston, Tex. from 4th to 7th of May 1998, pp. 149-155.
  (g) Marker et al.; “Anaconda: Joint Development Project Leads to Digitally Controlled Composite Coiled Tubing Drilling System”, Paper presented at the SPEI/COTA, Coiled Tubing Roundtable held in Houston, Tex. from 5th to 6th of Apr., 2000, pp. 1-9.
  (h) Measures R. M.; “Smart Structures with Nerves of Glass”, Prog. Aerospace Sc. 26(4):289-351 (1989).
(i) Measures et al.; “Fiber Optic Sensors for Smart Structures”, Optics and Lasers Engineering 16: 127-152 (1992)(j) Poper Peter; “Braiding”, International Encyclopedia of Composites, Published by VGH, Publishers, Inc., 220 English 23rd Street, Suite 909, New York, N.Y. 10010.
• (k) Quigley et al., “Development and Application of a Novel Coiled Tubing String for Concentric Workover Services”, Paper presented at the 1997 Offshore Technology Conference held in Houston, Tex. from 5th to 8th of May 1997, pp. 189-202.
(l) Sas-Jaworsky II and Bell Steve “Innovative Applications Stimulated Coiled Tubing Development”, World Oil, 217(6): 61 (June 1996).(m) Sas-Jaworsky II and Mark Elliot Teel; “Coiled Tubing 1995 Update: Production Applications”, World Oil, 216 (6): 97 (June 1995).
• (n) Sas-Jaworsky, A. and J. G. Williams, “Advanced composites enhance coiled tubing capabilities”, World Oil, pp. 57-69 (April 1994).
  (o) Sas-Jaworsky, A. and J. G. Williams, “Development of a composite coiled tubing for oilfield services”, Society of Petroleum Engineers, SPE 26536, pp. 1-11 (1993).
  (p) Sas-Jaworsky, A. and J. G. Williams, “Enabling capabilities and potential application of composite coiled tubing”, Proceedings of World Oil's 2nd International Conference on Coiled Tubing Technology, pp. 2-9 (1994).
(p) Sas-Jaworsky II Alex; “Developments Position CT for Future Prominence”, The American Oil & Gas Reporter, pp. 87-92 (March 1996).
• (r) Moe Wood T., et al.; “Spoolable, Composite Tubing for Chemical and Water Injection and Hydraulic Valve Operation”, Proceedings of the 11th International Conference on Offshore Mechanics and Arctic Engineering-1992, vol. III, Part A-Materials Engineering, pp. 199-207 (1992).
  (s) Shuart J. M. et al.; “Compression Behavior of 450-Dominated Laminates with a Circular Hole of Impact Damage”, AIAA Journal 24(1): 115-122 (January 1986).
(t) Silverman A. Seth, “Spoolable Composite Pipe for Offshore Applications”, Materials Selection & Design pp. 48-50 (January 1997).
• (u) Rispler K. et al.; “Composite Coiled Tubing in Harsh Completion/Workover Environments”, paper presented at the SPE Gas Technology Symposium and Exhibition held in Calgary, Alberta, Canada, on Mar. 15-18, 1998, pp. 405-410.
  (v) Williams G. J. et al.; “Composite Spoolable Pipe Development, Advancements, and Limitations”, Paper presented at the 2000 Offshore Technology Conference held in Houston Tex. from 1st to 4th of May 2000, pp. 1-16.
• A relevant reference for well management systems includes U.S. Pat. No. 6,257,332, entitled “Well Management System”, which issued on Jul. 10, 2001, that is assigned to the Halliburton Energy Services, Inc., an entire copy of which incorporated herein by reference.
• Typical procedures used in the oil and gas industries to drill and complete wells are well documented. For example, such procedures are documented in the entire “Rotary Drilling Series” published by the Petroleum Extension Service of The University of Texas at Austin, Austin, Tex. that is incorporated herein by reference in its entirety that is comprised of the following:
Unit I—“The Rig and Its Maintenance” (12 Lessons);Unit II—“Normal Drilling Operations” (5 Lessons);Unit III—Nonroutine Rig Operations (4 Lessons);Unit IV—Man Management and Rig Management (1 Lesson);
• and Unit V—Offshore Technology (9 Lessons). All of the individual Glossaries of all of the above Lessons in their entirety are also explicitly incorporated herein, and all definitions in those Glossaries shall be considered to be explicitly referenced and/or defined herein.
• Additional procedures used in the oil and gas industries to drill and complete wells are well documented in the series entitled “Lessons in Well Servicing and Workover” published by the Petroleum Extension Service of The University of Texas at Austin, Austin, Tex. that is incorporated herein by reference in its entirety that is comprised of all 12 Lessons. All of the individual Glossaries of all of the above Lessons in their entirety are also explicitly incorporated herein, and any and all definitions in those Glossaries shall be considered to be explicitly referenced and/or defined herein.
• Entire copies of each and every reference explicitly cited above in this section entitled “Description of the Related Art” are incorporated herein by reference.
• At the time of the filing of the application herein, the applicant is unaware of any additional art that is particularly relevant to the invention other than that cited in the above defined “related” U.S. patents, the “related” co-pending U.S. patent applications, the “related” co-pending PCT Application, and the “related” U.S. Disclosure Documents that are specified in the first paragraphs of this application.
SUMMARY OF THE INVENTION
• An object of the invention is to provide high power umbilicals for subterranean electric drilling.
• Another object of the invention is to provide high power umbilicals that allow subterranean electric drilling machines to drill boreholes of up to 20 miles laterally from surface drill sites.
• Another object of the invention is to provide high power umbilicals that allow the subterranean liner expansion tools to install casings within monobore wells to distances of up to 20 miles laterally from surface drill sites.
• Another object of the invention is to provide high power near neutrally buoyant umbilicals for subterranean electric drilling to reduce the frictional drag on the umbilicals.
• Yet another object of the invention is to provide a high power near neutrally buoyant umbilical that possesses high speed data communications and also provides a conduit for drilling mud.
• Another object of the invention is to provide an umbilical that delivers in excess of 60 kilowatts to a downhole electric motor that is a portion of a subterranean electric drilling machine.
• Yet another object of the invention is to provide a novel feedback control of a downhole electric motor that is a part of a subterranean electric drilling machine.
• Yet another object of the invention is to provide high power umbilicals to operate subsea remotely operated vehicles.
• Another object of the invention is to provide an umbilical to operate a subsea remotely operated vehicle that possesses high speed data communications and provides a conduit for fluids.
• Yet another object of the invention is to provide a novel feedback control of a downhole electric motor that comprises a portion of a remotely operated vehicle.
• Another object of the invention is to provide electric flowline immersion heater assemblies that may be retrofitted into existing subsea flowlines.
• Yet another object of the invention is to provide electrically heated composite umbilicals that may be retrofitted into existing subsea flowlines.
• Another object of the invention is to provide different types of electrically heated composite umbilicals that may be installed within subsea flowlines.
• Yet another object of the invention is to provide different types of electrically heated umbilicals.
• Another object of the invention is to provide different methods to convey electrically heated composite umbilicals into subsea flowlines.
• Yet another object of the invention is to provide different methods to convey electrically heated umbilicals into subsea flowlines.
• Another object of the invention is to provide electrically heated immersion heater systems to prevent the build up of wax and hydrates to prevent the blockage of subsea flowlines.
• Yet another object of the invention is to provide a hydraulic pump attached to the distant end of an electrically heated composite umbilical installed within a flowline to provide artificial lift to the produced hydrocarbons.
• Another object of the invention is to provide a hydraulic pump attached to the distant end of an electrically heated umbilical installed within a flowline to provide artificial lift to the produced hydrocarbons.
• Yet another object of the invention is to install an electrically heated composite umbilical within a flowline carrying heavy oils to reduce the viscosity of those heavy oils.
• Another object of the invention is to provide electrically heated composite umbilicals that are heated uniformly within a flowline.
• Yet another object of the invention is to provide electrically heated composite umbilicals that are heated nonuniformaly within a flowline.
• Yet another object of the invention is to provide electrically heated composite umbilicals that are substantially neutrally buoyant within the fluids present within the flowlines.
• Another object of the invention is to provide electrically heated umbilicals that are substantially neutrally buoyant within the fluids present within the flowlines.
• It is yet another object of the invention to provide an electrically heated immersion heater system that may be removed from the well, repaired, and retrofitted in the flowline without removing the flowline.
• It is another object of the invention to provide an electrically heated, substantially neutrally buoyant tabular umbilical to be used as a flowline from a subsea well.
• Yet further, it is another object of the invention to provide an electrically heated, positively neutrally buoyant tubular umbilical to be used as a flowline from a subsea well.
• It is yet another object of the invention to provide a substantially neutrally buoyant tabular umbilical to be used as a flowline from a subsea well.
• And finally, it is another object of the invention to provide a positively neutrally buoyant tubular umbilical to be used as a flowline from a subsea well.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 shows a section view of a umbilical that is substantially neutrally buoyant in drilling mud within the well which provides a conduit for drilling fluids that is capable of providing 320 horsepower of electrical power at a distance of up to 20 miles.
• FIG. 2 shows the uphole and downhole power management system for the composite umbilical shown inFIG. 1.
• FIG. 3 shows an electrical block diagram representing two conductors from one three phase delta circuit providing up to 160 horsepower of electrical power at a distance of up to 20 miles.
• FIG. 4 shows an umbilical carousel in the process of being constructed.
• FIG. 5 shows a computerized uphole management system for the umbilical that provides for the closed-loop automatic control of all uphole and downhole functions.
• FIG. 6 generally shows the subterranean electric drilling machine that is disposed within a previously installed borehole casing during the process of drilling a new borehole and simultaneously installing a section of expandable casing.
• FIG. 7 shows the casing hanger.
• FIG. 8 shows detail for a downhole pump motor assembly that is related to the downhole pump motor assembly inFIG. 6.
• FIG. 9 shows a subterranean electric drilling machine boring a new borehole from an offshore platform.
• FIG. 10 shows a section view of the subterranean liner expansion tool positioned within an unexpanded casing that is injecting new cement into the new borehole.
• FIG. 11 shows the subterranean liner expansion tool in the process of expanding the expandable casing within the new borehole before the new cement sets up.
• FIG. 12 shows the casing hanger after a portion of it has been expanded with the casing hanger setting tool inside the previously installed casing.
• FIG. 13 shows a section view of the monobore well, or near-monobore well, after passage of the subterranean liner expansion tool.
• FIG. 14 shows relevant parameters related to fluid flow rates through the umbilical.
• FIG. 15 shows various parameters related to tripping the subterranean electric drilling machine and the expandable casing into the well.
• FIG. 16 shows a subterranean electric drilling machine boring a new borehole under the ocean bottom from an onshore wellsite.
• FIG. 17 shows a subterranean electric drilling machine boring a new borehole under the earth from a land based drill site.
• FIG. 18 shows an open hole subterranean electric drilling machine that is drilling an open borehole in the earth.
• FIG. 19 shows screw drive subterranean electric drilling machine that is drilling an open borehole in the earth.
• FIG. 20 shows a cross section of another embodiment of an umbilical used for subterranean electric drilling machines, for open hole subterranean electric drilling machines, and for other applications.
• FIG. 21 shows yet another neutrally buoyant composite umbilical in 12 lb per gallon mud.
• FIG. 22 shows an umbilical providing power in excess of 60 kilowatts and communications to a remotely operated vehicle
• FIG. 23 shows a umbilical providing power in excess of 60 kilowatts, communications, and fluids to a remotely operated vehicle.
• FIG. 24 shows a sectional view of one preferred embodiment of a Smart Shuttle®.
• FIG. 25 shows a sectional view of a tractor deployer operated from an umbilical.
• FIG. 26 shows various devices that may be attached to the Retrieval Sub of the Smart Shuttle and the tractor conveyor.
• FIG. 27 shows a diagrammatic representation of functions that may be performed with the Smart Shuttle and the tractor conveyance system.
• FIG. 28 shows a subsea well providing produced hydrocarbons to a fixed platform through several subsea flowlines.
• FIG. 29 shows four subsea wells providing produced hydrocarbons to a Floating Production, Storage, and offloading structure (FPSO) through four different subsea flowlines.
• FIG. 30 shows an Electrically Heated Composite Umbilical (“EHCU”) installed within a subsea flowline that is providing produced hydrocarbons to a floating platform that was conveyed into place using a particular method of conveyance.
• FIG. 31 shows an embodiment of an Electric Flowline Immersion Heater Assembly (“EFIHA”) having an Electrically Heated Composite Umbilical (“EHCU”) in a subsea flowline that was conveyed into place using a Smart Shuttle that obtains its power from a wireline located within the EHCU.
• FIG. 32 shows another embodiment of an Electric Flowline Immersion Heater Assembly (“EHCU”) having an Electrically Heated Composite Umbilical in a subsea flowline that was conveyed into place using a Smart Shuttle that obtains its electrical power from additional electrical conductors within the EHCU.
• FIG. 33 shows yet another embodiment of an Electric Flowline Immersion Heater Assembly (“EFIHA”) having an Electrically Heated Composite Umbilical in a subsea flowline that was conveyed into place using particular methods of operation so that no fluid will be forced into the reservoir during transit of the EFIHA into the flowline.
• FIG. 34 shows still another embodiment of an Electric Flowline Immersion Heater Assembly having an Electrically Heated Composite Umbilical in a subsea flowline that was conveyed into place using yet another method of conveyance.
• FIG. 35 shows an Electrically Heated Composite Umbilical being installed within a flowline by a tractor means, where the host of the flowline is a floating platform.
• FIG. 36 shows a Pump-Down Conveyed Flowline Immersion Heater Assembly (“PDCFIHA”) possessing an Electrically Heated Composite Umbilical (“EHCU”) installed within a flowline, where the host of the flowline is a Floating Production, Storage and Offloading (“FPSO”) ship.
• FIG. 37 shows a Pump-Down Conveyed Flowline Immersion Heater Assembly (“PDCFIHA”) installed within a flowline, where the host of the flowline is a floating platform.
• FIG. 37A shows a Pump-Down Conveyed Flowline Immersion Heater Assembly (“PDCFIHA”) installed within a flowline to be used for artificial lift during hydrocarbon production, where the host of the flowline is a floating platform.
• FIG. 38 shows an Electric Flowline Immersion Heater Assembly (“EFIHA”) which possesses an Electrical Heated Composite Umbilical that is used to produce heavy oil from an open borehole that also uses a hydraulic pump for artificial lift.
• FIG. 39 an exploratory will with large volume fluid sampling capability obtained from a downhole sampling unit.
• FIG. 40 shows an apparatus that provides electrical power from a flowline penetrating connector to other subsea systems.
• FIG. 41 shows one embodiment of a composite umbilical used to uniformly heat a flowline.
• FIG. 42 shows a first resistor network used to electrically heat a composite umbilical.
• FIG. 43 shows an embodiment of a composite umbilical used to nonuniformly heat a flowline.
• FIG. 44 shows an embodiment of a second resistor network used to nonuniformly heat a composite umbilical.
• FIG. 45 shows an embodiment of an electrically heated umbilical that is surrounded with steel or synthetic armor.
• FIG. 46 shows an embodiment of an electrically heated umbilical that possesses an electric cable as a heating element within a steel coiled tubing.
• FIG. 47 shows another embodiment of an electrically heated umbilical that possesses an electric cable as a heating element within steel coiled tubing that is surrounded by thermal insulation.
• FIG. 48 shows yet another embodiment of an electrically heated umbilical that is a bundled umbilical possessing electric cables and tubes capable of carrying fluids.
• FIG. 49 shows one subsea well providing produced hydrocarbons to a Floating Production, Storage, and Offloading structure (FPSO) through a positively buoyant and electrically heated composite umbilical.
• FIG. 50 shows a cross section of one embodiment a positively buoyant electrically heated flowline.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
• FIG. 1 shows a section view of a preferred embodiment of an umbilical2. In this preferred embodiment, substantial portions of the umbilical are fabricated from one or more composite materials. Consequently umbilical2 is also called a composite umbilical. Composite umbilical2 provides a connection between the surface and other downhole tools (such as a subterranean electric drilling machine to be described later) which is capable of performing useful work at great distances from a well site. In the preferred embodiment shown inFIG. 1, the umbilical is capable of performing useful work at the distance of 20 miles away from a surface drilling site. This statement means that the umbilical is capable of performing useful work at any distance between 0 miles to 20 miles away from a wellsite. This connection is called an umbilical and it does not rotate like drill pipe and its capabilities are different from those of coiled tubing used in drilling operations.
• In particular,FIG. 1 shows an umbilical that is substantially neutrally buoyant in any specific density ofdrilling mud4 that is present in a wellbore. Thedrilling mud4 may also be called the drilling fluid. The symbol for the density of drilling mud is ρ (drilling mud). In this particular example of a preferred embodiment, the density of drilling mud present in the wellbore is 12 lbs/gallon.
• InFIG. 1, the composite umbilical is partially fabricated frominside pipe6. InFIG. 1, the umbilical has an inside diameter of ID1. In this particular embodiment, the inside diameter ID1 is equal to 4.5 inches. The inside diameter forms a hollow region through which fluids may be sent to, and from downhole. Put another way, the inside diameter forms a conduit through which fluids may be sent from the surface downhole, or from downhole to the surface. Therefore, the umbilical possesses a fluid conduit for conducting drilling fluids through the interior of the umbilical. The fluids present within the inside pipe are shown byelement8 inFIG. 1. The density of thefluids8 is defined to be the symbol ρ (umbilical fluid). For example, drilling mud may be sent downhole through the 4.5 inch ID pipe. The ID of this pipe is also called the interior of this pipe. Theinside pipe6 has wall thickness T1, but this legend is not shown inFIG. 1 for brevity. In this preferred embodiment, the wall thickness of the inside pipe T1 is 0.25 inches. The wall of theinside pipe6 is made from a composite material. This composite wall may have many layers of different composite materials made of different materials, each layer having a different specific gravity. As an example of one preferred embodiment, the composite material may be a carbon-based composite material. For reasons of simplicity, those layers are not shown inFIG. 1. However, there will be an average specific gravity of the interior pipe that is defined to be SG (inside pipe). In this preferred embodiment, the specific gravity of the inside pipe is equal to 1.5.
• InFIG. 1, the composite umbilical is partially fabricated fromoutside pipe10. InFIG. 1, the umbilical has an outside diameter of OD2 and this legend is shown inFIG. 1. In this preferred embodiment, the outside diameter OD2 is equal to 6.00 inches O.D. Consequently, the external portion of the composite umbilical appears to be a pipe having the outside diameter of OD2. Theoutside pipe10 has wall thickness T2, but this legend is not shown inFIG. 1 for brevity. In this preferred embodiment, the wall thickness of the outside pipe T2 is 0.25 inches. The wall of theoutside pipe10 is made from a composite material. This composite wall may have many layers of different composite materials made of different materials, each layer having a different specific gravity. In one preferred embodiment, the composite material may be a carbon-based composite material. Those layers are not shown inFIG. 1 for simplicity. For example, an outer layer of composite material may be chosen to be particularly abrasion resistant.
• As one example, the outer layer of composite material may be made of a carbon-based composite material. However, there will be an average specific gravity of the outside pipe that is defined to be SG (outside pipe). In this preferred embodiment, the specific gravity of the outside pipe is equal to 1.5.
• As shown inFIG. 1, theinterior pipe6 is asymmetrical located within theexterior pipe10 that forms an theasymmetric volume12 between the two pipes. Within theasymmetric volume12 between the two pipes are insulated current carrying electric wires designated by the legends A, B, C, D, E, and F inFIG. 1. Also shown inFIG. 1 is highspeed data link14. This high speed data link provides high speed data communications from the surface to downhole equipment, and from the downhole equipment to the surface. Highspeed data link14 is selected from a list including a fiber optic cable, a coaxial cable, and twisted wire cables. In the particular preferred embodiment of the invention shown inFIG. 1, the high speed data link is chosen to be a fiber optic cable. Theasymmetric volume12 between the two pipes that contains wires A, B, C, D, E, and F, and the fiber optic cable, is otherwise filled with syntactic foam material. This syntactic foam material is often made from silica microspheres that are embedded in a filler material, such as epoxy resin or other composite materials. The syntactic foam material has a specific gravity that is defined as SG (syntactic foam material). In this preferred embodiment of the invention, the specific gravity of the syntactic foam material is 0.825. In this preferred embodiment of the invention, syntactic foam material possessing silica microspheres is provided by the Cumming Corporation. The Cumming Corporation is located at 225 Bodwell Street, Avon, Mass. 02322. The Cumming Corporation can also be reached by telephone at (508) 580-2660 or by the internet at www.emersoncumming.com. The details on the syntactic foam material may be reviewed in detail inAttachment 28 to Provisional Patent Application No. 60/384,964, that has the Filing Date of Jun. 3, 2002, an entire copy of which is incorporated herein by reference. Using silica microspheres in a syntactic matrix provides the necessary buoyancy in high pressure wellbores. The high axial strength of the composite pipe construction compensates for variations in axial loads caused by mud weight and other density variations.
• InFIG. 1, wires A, B, C, D, E, and F are 0.355 inches O.D. insulated No. 4 AWG Wire. The insulation is rated at 14,000 volts DC, or O-peak AC. Wires A, B, and C comprise the first independent three phase delta circuit. Wires D, E, and F comprise the second independent three phase delta circuit. Each separate circuit is capable of providing 160 horsepower (119 kilowatts) over an umbilical length of 20 miles at the temperature of 150 degrees C. So, combined, the umbilical can deliver a total of 320 horsepower (238 kilowatts) at 20 miles to do work at that distance. At 320 horsepower, less than 1 watt per foot of power is dissipated in the form of heat, which makes this a practical design even if the umbilical is completely wound up on an umbilical carousel as shown in a later figure (FIG. 4). In this preferred embodiment, wires A, B, C, D, E, and F are No. 4 AWG stranded silver plated copper wire which are covered with insulation rated to 14,000 VDC at 200 degrees C., where each wire has a DC resistance of 0.250 ohms per 1000 feet at the temperature of 20 degrees C., where the nominal outside diameter of each insulated wire is 0.355 inches, and where each wire weighs 180 lbs/1000 feet. Each wire is Part Number FEP4FLEXSC provided by Allied Wire & Cable, Inc. which is located at 401 East 4th Street, Bridgeport, Pa. 19405, which may be reached by telephone at (800) 828-9473. The details on Allied Part Number FEP4FLEXSC may be reviewed in Attachment 27 to Provisional Patent Application No. 60/384,964, that has the Filing Date of Jun. 3, 2002, an entire copy of which is incorporated herein by reference.
• If theinside pipe6 is carrying 12 lb per gallon mud, and if the exterior pipe is immersed in 12 lb per gallon mud in the well, then the upward buoyant force in the above preferred embodiment of the umbilical is plus 5.9 lbs per 1000 feet of this umbilical. Assuming a coefficient of friction of 0.2, the total frictional “pull-back” on 20 miles of this umbilical is only 124 lbs. This “pull-back” does not include any differential fluid drag forces. This umbilical was chosen to have an extreme length which shows that the essentially neutrally buoyant umbilical overcomes most friction problems associated with umbilicals disposed in wells. For the details of this calculation of a net upward force of 5.9 lbs as described above, please refer to “Case J” ofAttachment 34 to Provisional Patent Application No. 60/384,964, that has the Filing Date of Jun. 3, 2002, an entire copy of which is incorporated herein by reference. Those particular calculations were performed on the date of Nov. 12, 2001. In these calculations, the density of water of 62.43 lbs/cubic foot was used to calculate the net forces acting on volumes having particular specific gravities. Please also see other relevant buoyancy calculations in Attachments 29 to 35 of Provisional Patent Application No. 60/384,964.
• The phrase “substantially neutrally buoyant”, “essentially neutrally buoyant”, “near neutral buoyant”, and “approximately neutrally buoyant” may be used interchangeably. For a substantially neutrally buoyant umbilical, or near neutrally buoyant umbilical, the downward force of gravity on a section of the umbilical of a given length is approximately balanced out by the upward buoyant force of well fluid acting on the umbilical of that given length. The density of mud in the well is strongly influenced by any cuttings from any drilling machine attached to the umbilical (to be described later). Similarly, the density of the fluids insidepipe6 may also be strongly influenced by any cuttings from the drilling machine (if reverse flow is used). So, the density of thedrilling mud4 and the density of fluids present within thepipe8 may vary with distance along the length of the umbilical. However, at any position along the length of the umbilical which is disposed in the well, the umbilical may be designed to be “substantially neutrally buoyant”, “essentially neutrally buoyant”, “near neutral buoyant” or “approximately neutrally buoyant”. In addition, using the design principles described herein, the entire length of the umbilical may be designed to be on average “substantially neutrally buoyant”, “essentially neutrally buoyant”, “near neutral buoyant”, or “approximately neutrally buoyant” over the entire length of the umbilical that is disposed within a wellbore.
• An umbilical that is “substantially neutrally buoyant”, “essentially neutrally buoyant”, “near neutral buoyant”, or “approximately neutrally buoyant” greatly reduces the frictional drag on the umbilical as it moves in the wellbore. That statement is evident from the following. The net force on a length of umbilical from gravity and buoyant forces is F. The coefficient of sliding friction is k. Therefore, the net “pull back force” P for the given length of the umbilical is given by:
• 
  P=Fk  Equation 1.
• The requirement of a near neutrally buoyant umbilical greatly reduces the frictional drag on the umbilical as it moves in the wellbore. This is a particularly important point. If an umbilical is “substantially neutrally buoyant”, “essentially neutrally buoyant”, “near neutral buoyant”, or “approximately neutrally buoyant” then the frictional drag on the umbilical is greatly reduced as it moves through the wellbore. There are other details to consider such as the starting friction, any sticky substances in the well, drag due to viscous forces, etc. However, Equation 1 forms the basis for providing high electrical power through umbilicals at great distances such as 20 miles from a drilling site. As stated before in relation to this preferred embodiment, with a net force on 1,000 feet of the umbilical being only plus 5.9 lbs (an upward force), assuming a coefficient of friction of 0.2, the total frictional “pull-back” on 20 miles of this umbilical is only 124 lbs.
• The preferred embodiment also calls for other reasonable design requirements on the umbilical. The umbilical needs significant axial strength (to pull the drilling machine from the well in the event of equipment failure downhole as explained later) that would require a 160,000 lbs design load. The umbilical must provide an internal pressure capacity (shut-in pressure capacity of the well) of about 10,000 psi. The collapse resistance of the umbilical must exceed a 6,000 psi differential pressure. The umbilical must have the ability to work in at least 120 degrees C., and preferably, 150 degrees C. Composites are now routinely used at 120 degrees C., and experiments are now being conducted on composites at 150 degrees C. Hollow high-strength glass may replace carbon fiber composites for a cost savings, but there will be a weight penalty, thereby increasing frictional drag.
• The umbilical may occasionally be damaged during its use and require field repairs. Repairs will be accomplished by cutting out the damaged part and using field installable end connections to rejoin the intact umbilical sections. The end connections will also join various sections of umbilical that may be stored separately at the surface. These couplings are expected to slightly reduce the ID and increase the umbilical OD.
• The particular asymmetric design shown inFIG. 1 was selected as a preferred embodiment in part because it illustrates the various considerations necessary to design and build such a high power umbilical that is neutrally buoyant in well fluids. Other more symmetric designs for such an umbilical are shown in another preferred embodiment shown inFIG. 20 below. The references cited above in the section entitled “Description of the Related Art” provide the generally known methods used in the industry to construct composite umbilicals.
• FIG. 2 shows the uphole and downhole power management system for the composite umbilical shown inFIG. 1. Wires A, B, andfiber optic cable14, which were identified inFIG. 1, are shown inFIG. 2. InFIG. 2, the surface of the earth is shown figurative aselement16. Any function shown aboveelement16 is identified as an “uphole function”, and any function shown belowelement16 is identified as a “downhole function”.
• InFIG. 2, only wires A and B of a first three phase delta circuit are shown. Three phase delta is an AC circuit having three wires (for example A, B, and C), each wire of which carries a an AC current, and there exists a voltage difference between each wire. There exists phase relationships between the current vs. time in each wire. There exits phase relationships between the voltage vs. time in each wire. However, inFIG. 2, wire C is not shown for simplicity.Electrical generator18 provides three phase delta power throughcable19 to variable voltage andfrequency converter20. The variable voltage and frequency converter possesses electronics that provides measurement of the voltages, currents and phases of the three phase delta circuit (although that electronics is not shown inFIG. 2 for the purposes of simplicity). Electrical power is delivered by wires A and B to the downholeelectrical load22. In one preferred embodiment, the electrical load is a downhole electric motor. The voltage, current, the relevant phases, and other parameters of the electrical load are measured with sensingunit24.Sensing unit24 is marked with the legend “V” indicating that at least the voltage V is measured between wires A and B atelectrical load22.Sensing unit24 is attached to the electrical input terminals of the downhole electrical load. If this is a downhole electrical motor, thesensing unit24 is attached to the electrical input terminals of the electric motor.
• Sensing unit24 also possesses suitable electronics that sends the measured downhole information to the surface throughoptical fiber14. The downhole information is sent byoptical fiber14 that provides the measured information tocomputer system26. The measured downhole information is digitized with related instrumentation (not shown for the purposes of simplicity inFIG. 2), and the downhole information is forwarded uphole by light pulses sent through theoptical fiber14.
• InFIG. 2, thecomputer system26 also possesses related electronics to implement the following. The computer system and related electronics provides commands to the variable voltage andfrequency converter20 byelectronic feedback loop28 to provide the necessary voltage, current, phases, and frequency as required by thedownhole load22. Consequently,FIG. 2 shows a closed-loop, dynamic feedback system, where downhole load parameters are measured, the information is sent uphole, and the uphole system is automatically adjusted to provide what is required to properly operate the electrical load. The point is that thefeedback loop28 fromcomputer20 is used to produce the required frequency, voltage, current and phases required by thedownhole load22. This is an example of the feedback control of thedownhole load22, which may be a downhole electric motor in several preferred embodiments.
• In an alternative embodiment of feedback control, the feedback loop fromcomputer26 inFIG. 2 is used to control the RPM of a motor generator whose O-peak output voltage may be easily varied, which provides conveniently controlled frequency and voltage outputs, although that minor variation of the preferred embodiment is not shown in a separate figure for the purposes of brevity. In this case, the feedback loop fromcomputer26 is first used to control the RPM of the motor, and is also used for the second purpose to control the output voltage, frequency, and phase from the generator attached to the motor which makes the motor generator assembly.
• Additional measured downhole load parameters are also sent uphole through the optical fiber. For example, in one preferred embodiment,element22 inFIG. 2 is an electrical motor, and as an example, the measured RPM, the current drawn by the motor through its input terminals, the voltage across its input terminals, and the phases of the voltages and current vs. time, the temperature, torque, etc. of that electrical motor can be sent uphole through theoptical fiber14. In other preferred embodiments, theelectrical load22 is a submersible electric drilling machine, and in another embodiment, the electrical load is a remotely operated vehicle.
• The system shown inFIG. 2 controls a first three phase delta circuit that energizes wires A, B, and C inFIG. 1. A second similar system to that shown inFIG. 2 controls the power derived to wires D, E and F from a second three phase delta circuit. For simplicity, the second three phase delta circuit is not shown inFIG. 2. Such a system is capable of delivering 320 horsepower through an umbilical disposed in a wellbore shown inFIG. 1 that has a length of up to 20 miles. This is important, because most of the available motors for downhole use are AC motors, and are not DC motors.
• The AC power management system shown inFIG. 2 has at least several advantages. First, DC voltages are not used which would generally require a “chopper” to convert DC to AC to operate most currently available downhole electric motors. Such high power choppers are complex, often large, and generate considerable heat. Second, no downhole transformer is necessary because of the active closed-loop feedback system shown inFIG. 2.
• However, the basic feedback control of downhole parameters as such as voltage and current are also useful for a DC power management system for DC electric motors that can be used in a subterranean electric drilling machine. Accordingly, another preferred embodiment of the invention is controlling DC voltages with an analogous system as outlined inFIG. 2.
• FIG. 3 shows how three phase power of 160 horsepower (119 kilowatts) can be delivered through the electrical conductors inFIGS. 1 and 2 to distances of 20 miles. This means that this power can be delivered from 0 miles to 20 miles away from a drill site for example. Two “legs” of the three phase delta circuit are shown inFIG. 3 as wires A and B (wire C of the three phase delta circuit is not shown for simplicity). The resistances of a length of 20 miles of the wire is simulated with resistors having the magnitude of resistance in ohms of “R1”. The legend “R1” appears inFIG. 3. These two resistors are also respectively labeled aselements30 and32. In a preferred embodiment, the load at the end of the umbilical is simulated with a downholeelectric motor34 requiring 2,500 volts O-peak at 45 amps O-peak between any two wires of the three phase wiring system operating at 60 Hz. As a practical case, this “downhole motor” could in principle be comprised of two each REDA, 4 Pole Motors, each requiring 1250 volts O-peak, at 45 amps O-peak, having a nominal RPM of about 1700 RPM. The current flowing through wires A and B is represented by the legend I(t) inFIG. 3. This required motor voltage is represented by the legend V_M(t). The closed-loop, dynamic feedback system described inFIG. 2 automatically and continuously adjusts the voltage provided downhole to the motor that is measured with sensingunit24 inFIG. 2. In this preferred embodiment, typically, the variable voltage andfrequency converter20 inFIG. 2 provides 6,182 volts O-peak and provides 45 amps O-peak between any two legs of the three phase circuit. The supplied voltage is represented byelement36 inFIG. 3. The voltage supplied by the voltage andfrequency converter20 is represented by the legend V_S(t) inFIG. 3. The point of this is that using the above described feedback system and reasonable gauge wiring, it is possible to actually deliver 160 horsepower (119 kilowatts) at a distance of 20 miles.
• FIG. 3 shows a first independent circuit that provides 2,500 volts O-peak to a load, a motor in this preferred embodiment, at distances of up to 20 miles between wires A, B, and C respectively, and the motor may draw up to 45 amps O-peak between any pairs of wires, A-B, B-C, or C-A. A second independent circuit, that is not shown for simplicity, also provides 2,500 volts O-peak to another motor at distances to 20 miles between wires D, E, and F respectively, and that motor may also draw up to 45 amps O-peak from any wire D, E, and F. Such voltages and currents are necessary for two series operatedREDA 4 Pole Motors, each rated for 80 Horsepower (as shown in a later figure,FIG. 8). REDA is a manufacturer called “Reda Div. Camco International, Inc.” that may be reached at 4th & Dewey, Bartlesville, Okla. 74005, having the telephone number of (918) 661-2000, that has a website that may be reached through www.schlumberger.com.
• In summary, the umbilical2 inFIG. 1 must carry high power and high speed communications (320 hp—two circuits of 160 hp each—and fiber optic communications). An A.C. voltage, transformerless, downhole electrical power arrangement is used. The input power and voltage are managed topside to maintain constant downhole load voltage. In one preferred embodiment, one of the two circuits is dedicated to the downhole mud pump (or Smart Shuttle®) service, while the second circuit operates other Downhole Rig™ functions such as the rotation and weight loading of a drilling bit, which will be described in later figures. In various preferred embodiments, the various downhole motors feature soft start controls allowing the topside power supply to reliably track power demand.
• In the above preferred embodiment, a three phase delta power circuit is used. In principle, any electrical power system may be used including 208 Y and related power systems, and ordinary single phase power systems.
• FIG. 4 shows an umbilical carousel in the process of being constructed. This equipment is similar to flexible pipe handling equipment now used in the industry. Afirst carousel flange38 possessesinterior spokes40 that forms the inside diameter of the umbilical carousel. Wound on those interior spokes is the umbilical42. A second carousel flange (not shown) encloses the wound up umbilical, although it not shown in the interest of brevity. In one preferred embodiment, the umbilical42 is the same umbilical as shown inFIG. 1 that is 6 inches OD. The umbilical may be stored and operated as a single line. However, the umbilical is preferably divided into several smaller lengths, as an example 5 miles each, and stored on smaller carousals or drums to reduce the fluid friction losses as compared to one 20-mile continuous length. A level wind is provided on each carousel to correctly wrap the pipe as it is pulled from the well and returned to the carousel for storage.
• Each carousel holding 5 miles of the 6 inch OD umbilical is approximately 8 ft tall with an outside diameter of 22 ft. The mud filled umbilical weighs approximately 234 tons. Unless this equipment is installed on offshore vessels, it is not easily moved. For this reason, drilling centers where the rig is assembled are expected to use the equipment over its useful life. Such carousals may be supplied by Coflexip Stena Offshore, Inc. located at 7660 Woodway,Suite 390, Houston, Tex. 77063, having the telephone number (713) 789-8540, which has its website at www.coflexip.com. Such carousals may also be supplied by Oceaneering International, Inc. located at 11911 FM 529, Houston, Tex. 77401, having telephone number (713) 329-4500, which has its website at www.oceaneering.com.
• Much surface equipment is needed in support of handling the umbilical. This surface equipment is briefly described in the following. Much of this equipment may be supplied by a firm located in Holland called Huisman-Itrec, that may be located at Admiraal Trompstraat 2-3115 HH Schiedam, P.O. Box 150-3100 AD Schiedam, The Netherlands, Harbour No. 561, having the telephone number of 31(0) 10 245 22 22, that has its website at www.Huisman-Itrec.com.
• Stripper heads and surface blow-out preventers (BOP's) provide an OD pressure seal to the umbilical, although no figures are provided to show this feature for simplicity. This equipment has a similar function to a coiled tubing stripper head, except it handles the larger umbilical OD sizes. In practice, the actual sealing element is expected to be dual 13⅝″ annular stripping BOPs with grease injection to lubricate the sealing elements as the umbilical moves through the sealing elements. This approach of dual stripping units allows the umbilical mechanical couplings to be transitioned into the well. The surface BOPs provide for surface well control in the event of a well kick. These (shear, pipe & blind ram) BOPs will be located between the wellhead and the stripping annular units.
• An injector unit is required on the surface, although no figure is shown for simplicity. A 100-ton linear traction unit is preferred for this application. The injection unit provides drilling umbilical pushing and pulling loads at speeds to 10 feet per second. The maximum loads will be at low speeds. Speed will be limited by mudflows within the wellbore. This injector unit has a function similar to a coiled tubing injector but practically is closer in size and performance to a pipeline tensioner used to lay flexible pipe. Similar units are used for the handling and installation of flexible pipe by such firms as Coflexip Stena Offshore, Inc.; Wellstream, Inc.; and NKT Flexibles I/S. The address of Coflexip Stena Offshore, Inc. has been provided above. Wellstream, Inc. is a subsidiary of Halliburton Energy Services, and may be reached at 10200 Bellaire Boulevard, Houston, Tex. 77072-5299, having the telephone number of (281) 575-4033. NKT Flexibles I/S is a firm located in Denmark having the address ofPriorparken 510, DK-2605 Broendby, Denmark, having the telephone of 45 43 48 30 00, that has its website at www.nktflexibles.com.
• A surface mud system is required for the umbilical, although no figures showing this feature are provided for the sake of brevity. A large volume of working mud will be needed to manage the umbilical volume while tripping in the hole. For 20-mile offset operations, an active mud tank volume of 3,500 barrels may be required. This is similar to some large offshore drilling rigs in capacity. A minimum of two 750 hp surface mud pumps will be required for the preferred embodiment. The other details concerning the mud system will be presented in relation to a forthcoming figure (FIG. 14).
• A surface rig is needed to support umbilical and casing operations, although no figure is presented showing this detail in the interests of brevity. The surface rig handles and makes-up the casing as it is run into the hole. In many respects, it is similar to conventional coiled tubing drilling rigs, except it is much larger in size. During drilling operations, the best method for joining expandable casing is continuing to develop. Enventure Global Technology is developing an expandable threaded joint. Enventure also has commercially available various sizes of expandable pipes and can supply various means of joining lengths of the expandable pipe. Enventure Global Technology may be reached at 16200-A Park Row, Houston, Tex. 77084, having the telephone number of (281) 492-5000, that has its website at www.EnventureGT.com. Other alternatives of joining expandable is to weld long casing strings (similar to J-laying pipelines). The arrangement of surface rig equipment is compatible with both alternatives.
• FIG. 5 shows a computerized uphole management system for the umbilical. It is a portion of a preferred embodiment of an automated system to drill and complete oil and gas wells. It is also a portion of a preferred embodiment of a closed-loop system to drill and complete oil and gas wells.FIG. 5 shows the computer control of the umbilical carousel in a preferred embodiment of the invention.
• InFIG. 5, computer system26 (previously described inFIG. 2) has typical components in the industry including one or more processors, one or more non-volatile memories, one or more volatile memories, many software programs that can run concurrently or alternatively as the situation requires, etc., and all other features as necessary to provide computer control of all of the uphole functions. In this preferred embodiment, thissame computer system26 also has the capability to acquire data from, send commands to, and otherwise properly operate and control all downhole functions. Therefore LWD and MWD data is acquired by this same computer system when appropriate. As a consequence, in one preferred embodiment, thecomputer system26 has all necessary components to interact with a subterranean electric drilling machine. In a “closed-loop” operation of the system, information obtained downhole from the downhole system is sent to the computer system that is executing a series of programmed steps, whereby those steps may be changed or altered depending upon the information received from the downhole sensor located within the downhole system.
• InFIG. 5, thecomputer system26 has acable44 that connects it to displayconsole46 that has one or more display screens. Thedisplay console46 displays data, program steps, and any information required to operate the entire uphole and downhole system. The display console is also connected viacable48 to alarm andcommunications system50 that provides proper notification to crews that servicing is required. Data entry andprogramming console52 provides means to enter any required digital or manual data, commands, or software as needed by the computer system, and it is connected to the computer system viacable54.
• InFIG. 5,computer system26 provides commands overcable56 to theelectronics interfacing system58 that has many functions. One function of the electronics interfacing system is to provide information to and from any downhole load throughcabling60 that is connected to the slip-ring62, as is typically used in the industry. Another function of the electronics interfacing system is to provide power to any downhole load throughcabling60 that is connected to the slip-ring62. The slip-ring62 is suitably mounted on the side of the assembledumbilical carousel64 inFIG. 5. Information provided to slip-ring62 then proceeds to wires A, B, C, D, E, F, and G within the umbilical wound up on the umbilical carousel. The umbilical66 proceeds to an sheave andtensioner device68 and then the umbilical proceeds downward atlocation70 towards the injection unit and on to the stripper heads and surface blow-out preventers (BOP's). The sheave antensioner device68 may place appropriate tension on the umbilical as required.
• InFIG. 5,electronics interfacing system58 also provides power and electronic control of thehydraulic system72 that controls the umbilical carousel through the connector atlocation74.Cabling76 provides the electrical connection between theelectronics interfacing system58 and thehydraulic system72 that controls the umbilical carousel. In addition,electronics interfacing system58 hasoutput cable78 that provides commands and control to the drilling righardware control system80 that controls various drilling rig functions and apparatus including the rotary drilling table motors, the mud pump motors, the pumps that control cement flow and other slurry materials as required, and all electronically controlled valves, and those functions are controlled throughcable bundle82 which has an arrow on it inFIG. 5 to indicate that this cabling goes to these enumerated items.
• In relation toFIG. 5,electronics interfacing system58 also hascable output84 to ancillary surface transducer andcommunications control system86 that provides any required surface transducers and/or communications devices required for communications with the downhole equipment. In a preferred embodiment, ancillary surface andcommunications system86 provides acoustic transmitters and acoustic receivers as may be required to communicate to and from certain downhole equipment. The ancillary surface andcommunications system86 is connected to the required transducers, etc. by cabling88 that has an arrow inFIG. 5 designating that this cabling proceeds to those enumerated transducers and other devices as may be required.Electrical generator18 provides three phase delta power to variable voltage andfrequency converter20 bycable90. The output from the voltage andfrequency converter20 is provided bycable92 to theelectronics interfacing system58. Power to wires A, B, C, D, E, F, and G, and signals to the fiber optic cable14 (not shown inFIG. 5, but which are defined inFIG. 1) are provided from theelectronics interfacing system58 throughcabling60 that is connected to the slip-ring62. Thecabling60 and the slip-ring provide the suitable electrical and fiber optic connections.Cabling60 possesses connection to wires A, B, C, D, E, F, and G, and to thefiber optic cable14. In certain preferred embodiments, there are two separated generators and voltage and frequency converters to independently control to first three phase delta system having wires A, B, and C, and the second three phase delta system having wires D, E, and F.
• With respect toFIG. 5, and to the closed-loop system to drill and complete oil and gas wells, standard electronic feedback control systems and designs are used to implement the entire system as described above, including those described in the book entitled “Theory and Problems of Feedback and Control Systems”, “Second Edition”, “Continuous (Analog) and Discrete (Digital)”, by J. J. DiStefano III, A. R. Stubberud, and I. J. Williams, Schaum's Outline Series, McGraw-Hill, Inc., New York, N.Y., 1990, 512 pages, an entire copy of which is incorporated herein by reference. Therefore, inFIG. 5, thecomputer system58 has the ability to communicate with, and to control, all of the above enumerated devices and functions that have been described to this point.
• To emphasize one major point inFIG. 5,computer system26 has the ability to receive information from one or more downhole sensors for the closed-loop system to drill and complete oil and gas wells. This computer system executes a sequence of programmed steps, but those steps may depend upon information obtained from at least one sensor located within the downhole system. This computer system provides the automatic control of the umbilical and any uphole and downhole functions related to the deployment of that umbilical.
• FIG. 6 generally shows the subterraneanelectric drilling machine94 that is disposed within a previously installedborehole casing96 that is surrounded by existingdownhole cement98. The previously installed casing ends atlocation100. The inside diameter of the previously installed casing is defined as “ID Casing”, but this legend is not shown onFIG. 6 for simplicity. The outside diameter of the previously installed casing is defined as “OD Casing”, but this legend is not shown onFIG. 6 for simplicity. The wall thickness of the previously installed casing is defined as “WT Casing”, but this legend is not shown inFIG. 6 for simplicity. The previously installed casing is located within ageological formation102.
• As shown inFIG. 6, the subterranean electric drilling machine is in the process of drilling anew borehole104 into the geological formation.Pilot bit106 is shown drilling thepilot hole108. The OD of the pilot bit is defined as “OD Pilot Bit”, but that legend is not shown inFIG. 6 for brevity. The ID of the pilot hole is defined as “ID Pilot Hole”, but that legend is not shown inFIG. 6 for brevity.Undercutters110 and112 expand the new borehole to full diameter. The OD of theundercutters110 and112 when in the fully extended position is defined as “OD Undercutters”, but that legend is not shown inFIG. 6 for the purpose of brevity. The overall ID of the new borehole so drilled is defined to be “ID of New Hole”, but that legend is not shown inFIG. 6 for the purposes of brevity. Thepilot bit106 and theundercutters110 and112 together form the entire “drill bit” of this assembly. This drill bit is an example of an “expandable drill bit”, also called a “retrievable drill bit”, that is also called a “retractable drill bit”. The following references describe such drill bits: U.S. patents: U.S. Pat. No. 3,552,508, C. C. Brown, entitled “Apparatus for Rotary Drilling of Wells Using Casing as the Drill Pipe”, that issued on Jan. 5, 1971, an entire copy of which is incorporated herein by reference; U.S. Pat. No. 3,603,411, H. D. Link, entitled “Retractable Drill Bits”, that issued on Sep. 7, 1971, an entire copy of which is incorporated herein by reference; U.S. Pat. No. 4,651,837, W. G. Mayfield, entitled “Downhole Retrievable Drill Bit”, that issued on Mar. 24, 1987, an entire copy of which is incorporated herein by reference; U.S. Pat. No. 4,962,822, J. H. Pascale, entitled “Downhole Drill Bit and Bit Coupling”, that issued on Oct. 16, 1990, an entire copy of which is incorporated herein by reference; and U.S. Pat. No. 5,197,553, R. E. Leturno, entitled “Drilling with Casing and Retrievable Drill Bit”, that issued on Mar. 30, 1993, an entire copy of which is incorporated herein by reference. Some experts in the industry call this type of drilling technology to be “drilling with casing”. For the purposes herein, the terms “retrievable drill bit”, “retrievable drill bit means”, “retractable drill bit” and “retractable drill bit means” may be used interchangeably. The combination of the pilot bit and retractable drill bit may also be replaced under certain circumstances with a bicenter drill bit. The retrievable drill bits and the bicenter bits are rotary drill bits.
• When theundercutters110 and112 are retracted into their closed positions, then they can be pulled through the unexpaded casing, and then the entire subterranean electric drilling machine can removed from the previously installed casing because in their retracted positions, the OD of the undercutters is less than the ID of the expandable casing and the ID of the previously installed casing. However, when the undercutters are in their extended position as shown inFIG. 6, the subterranean electric drilling machine is used to drill the new borehole.
• The downholeelectric motor114 of the subterranean drilling machine obtains its electrical energy from umbilical116. The downholeelectric motor114 is a rotary motor. In one preferred embodiment, the umbilical is the lower end of the particular composite umbilical that is shown inFIG. 1. Various electrical wires and connectors along the length of the subterranean electric drilling machine conduct electrical power from the umbilical to the downhole electric motor (which are designated figuratively by element118 which is not shown inFIG. 6 for the purposes of brevity). Downholeelectric motor114 also possesses internal sensors indicating the voltages between various inputs to the motor, the current drawn by various inputs to the motor, the power consumed by the motor, the temperature of the motor, the RPM of the motor, the torque delivered by the motor, etc. That information is digitized, sent thorough suitable electrical circuitry and connectors along the length of subterranean drilling machine (designated figuratively by element120 which is not shown inFIG. 6 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical in the form of suitable light pulses. Commands from the surface are also send downhole through the same bidirectional communications path. Such commands including changing RPM of the motor, etc.
• The downhole electric motor has an output shaft which is figuratively designated by element122, which is not shown inFIG. 6 for brevity. Electric motor output shaft122 proceeds through the swivel andseal unit124 to turnrotary shaft125 which in turn rotates theundercutters110 and112 and thepilot bit106.Rotary shaft125 is also called the “drilling work string” or simply the “drill pipe”. In this preferred embodiment, theundercutters110 and112, and thepilot bit106 comprise the “drill bit”. Therefore, in this preferred embodiment, electrical energy provided by umbilical116 to downholeelectric motor114 rotates the drill bit and bores thenew borehole104 into the geological formation.
• InFIG. 6,expandable casing126 generally surroundsrotary shaft125. Expandable casing is described in various references in the above section entitled “Description of the Related Art”. The initial OD of the expandable casing (before expansion) is defined to be “Initial OD of Expandable Casing”, but that legend is not shown inFIG. 6 for brevity. The initial ID of the expandable casing (before expansion) is defined to be “Initial ID of Expandable Casing”, but that legend is not shown inFIG. 6 for brevity. The initial wall thickness of the expandable casing (before expansion) is defined to be the “Initial WT of Expandable Casing”, but that legend is not shown inFIG. 6 for brevity. The length of theexpandable casing126 is defined to be “Length of Expandable Casing”, but that legend is not shown inFIG. 6 for brevity. The Length of the Expandable Casing can be quite long, and in one preferred embodiment can be at least several thousand feet long. In such a situation, the length of therotary shaft125 would be approximately the same length.
• InFIG. 6, the length of the submersible electric drilling machine is defined to be “Length of Submersible Electric Drilling Machine”, but that legend is not shown inFIG. 6 for brevity. The Length of the Expandable Casing can be much longer than the Length of Submersible Electric Drilling Machine. Thebroken lines128 inFIG. 6 indicate that the Length of the Expandable Casing can be quite long compared to the Length of the Submersible Electric Drilling Machine. The various elements inFIG. 6 are not in proportion.
• InFIG. 6, theexpandable casing126 is attached to thecasing hanger130. The casing hanger is shown inFIG. 7, and will be described in detail below. A portion of the casing hanger is surrounded by casinghanger seal132. The casinghanger setting tool134 is located within thecasing hanger130. When thenew borehole104 has been completed, the casinghanger setting tool134 is used to expand the casing hanger so that it can make positive hydraulic and mechanical contact to the interior of the previously installed downhole casing that is adjacent to the casing hanger seal.FIG. 10 below shows the casing hanger after it has been expanded with the casing hanger setting tool, but that will be described in detail in relation to thatFIG. 10.FIG. 12 below also shows the casing hanger after it has been expanded with the casing hanger setting tool, but that will be described in detail in relation to thatFIG. 12.
• Drilling operations typically require means to directionally drill, means to determine the location and direction of drilling, and means to perform measurements of geological formation properties during the drilling operations.Tool section136 provides the rotary steering device for directional drilling and the LWD/MWD instrumentation packages. Here LWD means “Logging While Drilling” and “MWD” means “Measurement While Drilling”. Typically, MWD instrumentation provides at least the location and direction of drilling. The LWD instrumentation provides typical geophysical measurements which include induction measurements, laterolog measurements, resistivity measurements, dielectric measurements, magnetic resonance imaging measurements, neutron measurements, gamma ray measurements; acoustic measurements, etc. This information may be used to determine the amount of oil and gas within a geological formation. Power for this instrumentation is obtained from the umbilical116.
• InFIG. 6, various electrical wires and connectors along the length of the subterranean electric drilling machine conduct electrical power from the umbilical to the rotary steering device and to the MWD/LWD instrumentation (which are designated figuratively by element138 which are not shown inFIG. 6 for the purposes of brevity). The sensors on the direction steering device and the MWD and LWD instrumentation provide information that is digitized, sent thorough suitable electrical circuitry and connectors along the length of subterranean drilling machine (designated figuratively by element139 which is not shown inFIG. 6 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical in the form of suitable light pulses. Commands from the surface are also send downhole through the same bidirectional communications path. For example, commands to change the direction of drilling may be sent downhole through this bidirectional communications path.
• InFIG. 6, first anchor and weight on bit mechanism (AWOBM)140 and second anchor and weight on bit mechanism (AWOBM)142 selectively anchor the subterranean electric drilling machine and provide suitable weight on bit for drilling purposes. First AWOBM possesses anchor means144 and146. Second AWOBM possesses anchor means148 and150. This is an example of a tandem anchor system. In one preferred embodiment, the tandem anchor means144,146,148 and150 are comprised of inflatable packer-like elements.
• InFIG. 6,first shaft152 couples second AWOBM to the downholeelectric motor114. In one preferred embodiment, thefirst shaft152 is of fixed length. In another preferred embodiment,first shaft152 is an extensible shaft.Mud flow channel154 is shown inFIG. 6 that will be more fully described later.
• InFIG. 6,second shaft156 couples the first AWOBM to the second AWOBM.Second shaft156 is an extensible shaft. In one preferred embodiment, first AWOBM can move itself with respect to one end of thesecond shaft156, and second AWOBM can also move itself with respect to the opposite end ofshaft156. In one embodiment, simple electric motor operated threaded screws and nuts suitably coupled tosecond shaft156 are used to provide such motion. Those threaded screws, nuts, and electric motors are not shown inFIG. 6 for the propose of simplicity. For other examples of related mechanisms, please refer to the following references: (a) Roy Marker, et al., in the paper entitled “Anaconda: Joint Development Project Leads to Digitally Controlled Composite Coiled Tubing Drilling System”, SPE 60750, presented at the SPE/ICoTA Coiled Tubing Roundtable, Houston, Tex., Apr. 5-6, 2000, and particularly inFIG. 8 entitled “Tractor-driven BHA”, an entire copy of which is incorporated herein by reference; and (b) U.S. Pat. No. 5,794,703 that issued on Aug. 18, 1998 that is entitled “Wellbore Tractor and Method of Moving an Item Through a Wellbore”, an entire copy of which is incorporated herein by reference.
• First anchor and weight on bit mechanism (AWOBM)140 and second anchor and weight on bit mechanism (AWOBM)142 provide extension mechanisms with electric powered assemblies that are used to advance the casing and provide bit weight during drilling operations. These mechanisms also resist the drilling torque of the bit by anchoring the rotary motor. In a preferred embodiment, the anchor packers are inflated and deflated with motor driven progressing cavity pumps. Using dedicated PCPs simplifies controls and valves to operate the mechanism.
• First anchor and weight on bit mechanism (AWOBM)140 and second anchor and weight on bit mechanism (AWOBM)142 are high strength anchor assemblies which provide axial load capacity at a relative slow axial advance rate. Should the suspended casing weight (in the vertical wellbore) during casing running procedures exceed the umbilical strength rating, then this mechanism may be used to lower the casing into the near horizontal wellbore.
• InFIG. 6, various electrical wires and connectors along the length of the subterranean electric drilling machine conduct electrical power from the umbilical to the first anchor and weight on bit mechanism (AWOBM)140 and to the second anchor and weight on bit mechanism (AWOBM)142 (which are designated figuratively by element160 which are not shown inFIG. 6 for the purposes of brevity). The first anchor and weight on bit mechanism (AWOBM)140 and second anchor and weight on bit mechanism (AWOBM)142 have many sensors including force sensors, torque sensors, position sensors, speed sensors, etc. Information from these sensors are sent thorough suitable electrical circuitry and connectors along the length of subterranean drilling machine (designated figuratively by element162 which is not shown inFIG. 6 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical in the form of suitable light pulses. Commands from the surface can also be sent downhole through this bidirectional communications path. For example, detailed commands can be sent to change the locations offirst AWOBM140 andsecond AWOBM142 or to change the effective load placed on the drilling bit by these mechanisms.
• InFIG. 6, first mud cuttings and bypass port (MCBP)164 allows mud and drill cuttings to pass by thefirst AWOBM140. Second mud cutting and bypass port (MCBP)166 allows mud and drill cutting to pass by thesecond AWOBM142. These are electrically operated ports. Various electrical wires and connectors along the length of the subterranean electric drilling machine conduct electrical power from the umbilical to the first MCBP and to the second MCBP (which are designated figuratively by element168 which are not shown inFIG. 6 for the purposes of brevity). The first MCBP and to the second MCBP have many sensors providing temperature, pressure, etc. The information from these sensors are sent through suitable electrical circuitry and connectors along the length of subterranean drilling machine (designated figuratively by element170 which is not shown inFIG. 6 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical in the form of suitable light pulses. Commands from the surface can also be sent downhole through this bidirectional communications path. For example, detailed commands can be sent to close first MCBP and to the second MCBP to prevent a well blow-out.
• InFIG. 6,mud carrying shaft172 is attached to the first AWOBM byhousing174. The female side of universal mud andelectrical connector176 is attached to the male side of universal mud andelectrical connector178. Progressingcavity pump180 is driven by a downhole pump motor assembly generally designated byelement182. A progressing cavity pump is abbreviated as a “PCP”. Progressingcavity pump180 also includes an integral flexible shaft as is typical in the industry. In one preferred embodiment, the downhole pump motor assembly generally designated byelement182 is comprised ofprotector184; first 80 horsepowerelectric motor186 requiring 1250 volts at 45 amps that runs at the nominal RPM of 1700 RPM; second 80 horsepowerelectric motor188 requiring 1250 volts at 45 amps that also runs at the nominal RPM of 1700 RPM;universal motor base190;gearbox protector192; andgearbox194 having a 4:1 reduction. The downhole pump motor assembly and a portion of the progressingcavity pump180 is covered byshroud196.
• Various electrical wires and connectors along the length of the subterranean electric drilling machine conduct electrical power from the umbilical to the downhole pump motor assembly (which are designated figuratively by element198 which are not shown inFIG. 6 for the purposes of brevity). The subterranean electric drilling machine has has many sensors including voltage sensors, current sensors, torque sensors, temperature sensors, RPM sensors, etc. The information from these sensors are sent thorough suitable electrical circuitry and connectors along the length of subterranean drilling machine (designated figuratively by element200 which is not shown inFIG. 6 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical in the form of suitable light pulses. Commands from the surface can also be sent downhole through this bidirectional communications path. For example, detailed commands can be sent to change the RPM of firstelectric motor186 and secondelectric motor188.
• FIG. 6 also shows three-way valve202. This three-way valve is used to change the direction of mud flow inside the subterranean electric drilling machine. The functions of the threeway202 valve will be described below.
• FIG. 6 also showsumbilical mud valve204. This mud valve is used to shut off mud flow, or otherwise prevent well blow-outs. Themud valve204 has a total of three positions: (a) open, namely it allows mud to flow through as shown inFIG. 6; (b) stop (not allow any mud to flow straight through); and (c) vent to the annulus between the umbilical116 and the ID of the previously installedcasing212 so that cement or cuttings can be cleaned from within the umbilical (which state is not shown inFIG. 6 for simplicity).
• Various electrical wires and connectors along the length of the subterranean electric drilling machine conduct electrical power from the umbilical to three-way valve202 and to the umbilical mud valve204 (which are designated figuratively by element206 which are not shown inFIG. 6 for the purposes of brevity). The three-way valve202 and theumbilical mud valve204 possess many sensors including pressure sensors, voltage sensors, current sensors, and temperature sensors, etc. The information from these sensors are sent thorough suitable electrical circuitry and connectors along the length of subterranean drilling machine (designated figuratively by element208 which is not shown inFIG. 6 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical in the form of suitable light pulses. Commands from the surface can also be sent downhole through this bidirectional communications path. For example, detailed commands can be sent to change set the three-way valve202 into any position, or to close, or open,umbilical valve204.
• In addition, SmartShuttle® seal210 is shown inFIG. 6.Smart Shuttle seal210 is attached to a portion ofshroud180. For the purposes of succinct reference within this disclosure, the above entire list of Provisional Patent Applications, the U.S. patents that have issued, the Pending U.S. patent applications that appear under the title of “Cross-References to Related Applications”, the foreign pending patent applications under “Related PCT Applications”, and the above U.S. Disclosure Documents under of “Related U.S. Disclosure Documents”, all having William Banning Vail III as at least one of the inventors, is owned by the firm Smart Drilling and Completion, Inc. (“SDCI”), and therefore this intellectual property is defined herein to be the “SDCI Intellectual Property” or simply “SDCI IP” as an abbreviation. Smart Drilling and Completion, Inc. may be reached at 3123-198th Place S. E., Bothell, Wash.98012, having the telephone number of (425) 486-8789, that has the website of www.Smart-Drilling-and-Completion.com. The Smart Shuttle is extensively described in the above defined “SDCI IP”. The principal of operation of the Smart Shuttle is also described below in relation toFIG. 24. Theshroud196 extends to the left inFIG. 6 so that theSmart Shuttles seal210 is installed on a portion of that shroud.
• In a preferred embodiment shown inFIG. 6. A reverse mud circulation system has been configured with the umbilical in the wellbore. Fresh mud travels from the surface down the annuli between the well casing and the umbilical designated byelement212. The right-hand side ofFIG. 6 is “down” inFIG. 6. Fresh mud travels down from the surface as indicated by various arrows throughout the subterranean drilling machine. Clean mud then flows through the interior of theshroud214 to the three-way valve202. In one preferred embodiment, the three-way valve directs mud into the input of the progressing cavity pump so that the pump boosts the pressure of the mud delivered to the drill bit. This is called “Position A” of the three-way mud valve. The detailed tubing and other hardware necessary to accomplish the details of “Position A” is not shown inFIG. 6 for the purpose of simplicity. In “Position A”, clean mud then flows through the interior of the male side of universal mud andelectrical connector178; then through the female side of universal mud andelectrical connector176; then throughmud carrying shaft172; then throughmud flow channel158; then through the interior ofsecond shaft156; then throughmud flow channel154; then through the interior offirst shaft152; then through the swivel andseal unit124; then throughrotary shaft125; and then through the mud channels inpilot bit108.
• InFIG. 6, cuttings laden mud then returns to the surface through the following path. The cuttings laden mud flows up between the outside diameter of theexpandable casing126 and the inside diameter of thenew borehole104; then through the second mud cutting and bypass port (MCBP)166; then through the first mud cuttings and bypass port (MCBP)164; then through the volume between the exterior of theshroud196 and the ID of the previously installedborehole casing96; then throughcross-over system216; and then into umbilical116 and through theumbilical mud valve204 and then to the surface of the earth through the remainder of the umbilical disposed in the wellbore.
• Cuttings laden mud returns to the surface flowing through the ID of the umbilical. The purpose is to keep the wellbore clean. The subterraneanelectric drilling machine94 may be recovered to the surface while cuttings and mud fill the umbilical. Time to circulate the umbilical clean is not needed prior to tripping out of the hole.
• In the preferred embodiment illustrated inFIG. 6, the clean mud is provided a booster pressure to improve bit hydraulics. If a bit is selected that produces fine cuttings, the PCP mud pump is compatible with pumping the cuttings filled mud. In an alternative design, the benefit for pumping the cuttings is a reduction in backpressure held on the geological formation.
• InFIG. 6, there are two other positions of the three way-valve202, “Position B”, and “Position C”. In “Position B” of the three-way valve, thePCP pump180 is not used to boost the mud pressure delivered through the mud channels of thepilot bit108. Here, clean mud flows through the interior of theshroud214 to the three-way valve202, and then directly into the male side of universal mud andelectrical connector178 and through the remaining portions of the subterranean electric drilling machine to the mud channels of thepilot bit108. The detailed configuration of pipes and other related hardware to accomplish this mode of operation is not shown inFIG. 6 for the purpose of brevity.
• InFIG. 6, Position C of the three-way valve202 allows the entire subterranean drilling machine to move within the previously installedborehole casing96. The fluid filled region defined between the subterranean drilling machine and the interior of the previously installed borehole casing is designated byelement218 inFIG. 6. As previously stated, the fluid filled region defined between the inside of the previously installed casing and the outside diameter of the umbilical, which is the annuli between the well casing and the umbilical, is designated byelement212. In “Position C” of the three-way valve202, fluids are pumped from theregion218 intoregion212. If there is a good seal between the exterior of the umbilical and the borehole at the surface produced by the stripper heads and surface blow-out preventers (BOP's), then the existence of the SmartShuttle® seal210 causes the subterranean drilling machine to go down into the well. Reversing the PCP, causes the subterranean electric drilling machine to reverse direction. For a more detailed description of the operation of a Smart Shuttle, please refer to the above defined “SDCI IP”, entire copies of which are incorporated herein by reference. “Position C” of the three-way valve202 provides an important function to rapidly trip the subterranean electric drilling machine to the surface and back should any drilling component need maintenance or replacement. This capability provides operational flexibility for the system. Based upon existing designs with currently available downhole electric motors and progressing cavity pumps, practical speeds of 10 feet per second can be anticipated while pulling a load of at least 4,000 lbs.
• InFIG. 6, the fluid filled region between thecasing hanger seal132 and thepilot bit106 is designated byelement220. During drilling operations, the mud pressure inregion212 is defined to be P1; the mud pressure in the interior of the shroud defined byelement214 is P2; the mud pressure at the input to the three-way valve202 is P3; the mud pressure within the male side of universal mud andelectrical connector178 is P4; the mud pressure inside the mud channels of thepilot bit108 is P5; the pressure withinregion220 is P5; the pressure withinregion218 is P6; and the pressure within the umbilical116 is P6.
• The subterranean electric drilling machine inFIG. 6 provides other benefits. Since the anchor points secure the drilling machine in the well's casing and mudflow paths must pass through valves within the machine, the entire unit serves the function of a downhole packer with safety valve and serves as a BOP located downhole, or Downhole BOPX. The BOP is comprised of first mud cuttings and bypass port (MCBP)164, second mud cutting and bypass port (MCBP)166, and theumbilical mud valve204 provide the required functions of a BOP located downhole.
• It is also worthwhile to make a few more comments about the downholeelectric motor114. This electric motor rotates the drilling bit. This electric motor may possess a gearbox to match the bit's speed requirements. Monitoring the motor's power, RPM, torque, current drawn, voltage drawn etc., provides significant information about the condition of the bit and its drilling performance. As one particular example, the electric motor is chosen to be aREDA 4 pole, 80 horsepower, electric motor requiring 1250 volts at 45 amps that runs at the nominal RPM of 1700 RPM that is 5.4 inches OD and 31.5 inches long. The RPM of this motor may be conveniently varied by varying the frequency of the voltage applied to it as is indicated byFIG. 2 and the related description. In one preferred embodiment, the RPM of the electric motor in the subterranean electric drilling machine is varied between about 900 RPM to 2,500 RPM. In this one preferred embodiment, the particular REDA motor does not need a gearbox for this application. In another preferred embodiment, two such REDA motors are operated in series that provide a net downhole motor capable of providing 160 horsepower to a rotating drill bit at the rotation speed between 900 RPM and 2,500 RPM. The RPM and other parameters of the downhole motor are controlled bycomputer system26 inFIG. 5. Another preferred embodiment uses the electric motor described in U.S. Disclosure Document No. 498,720 filed on Aug. 17, 2001 that is entitled in part “Electric Motor Powered Rock Drill Bit Having Inner and Outer Counter-Rotating Cutters and Having Expandable/Retractable Outer Cutters to Drill Boreholes into Geological Formations”, an entire copy of which is incorporated herein by reference.
• The drilling fluid transitions from a nonrotating element which isfirst shaft152, into a rotating pipe that isrotary shaft125. The swivel andseal unit124 prevents fluid leaks in this area. Unlike a swivel-packing gland, this seal operates at a relative low differential pressure. Suitable rotating seal assemblies are commercially available for these conditions. Electric power and communications from the fixed (non-rotating) components to the rotating assembly is required. An inductive connection or a slip-ring assembly will provide the power, communication and control linkage through the swivel andseal unit124 to the fiber optic communication system and the power available through the umbilical. However, the details for either the inductive connection or slip-ring assembly are not shown inFIG. 6 in the interests of simplicity.
• FIG. 6 as described above drills the borehole with the long section ofexpandable casing126 carried into thenew hole104 as the new hole is drilled. However, in an alternative preferred embodiment, a short section ofexpandable pipe126 is used to drill the borehole, then the subterranean electric drilling machine is retrieved from the wellbore, and then that machine conveys into the well the long section ofexpandable casing126 to be cemented and expanded into place within thenew borehole104.
• FIG. 6 as described, uses thepilot bit106 and the twoundercutters110 and112 as the “drill bit” to drill thenew borehole104. However, a bicenter bit as is used in the industry could also be used as the “drill bit” inFIG. 6, provided it had suitable dimensions to be withdrawn through the ID of the unexpanded state of theexpandable casing126, and through the interior of the previously installedborehole casing96.
• In relation toFIG. 1, wires A, B, and C comprise the first independent three phase delta circuit. Wires D, E, and F comprise the second independent three phase delta circuit. Each separate circuit is capable of providing 160 horsepower (119 kilowatts) over an umbilical length of 20 miles. In relation toFIG. 6, and in one preferred embodiment, the first independent three phase delta circuit provides up to 160 horsepower to the downholeelectric motor114. In relation toFIG. 6, and in one preferred embodiment, the second independent three phase delta circuit provides up to 160 horsepower to the downholepump motor assembly182 inFIG. 6. In one preferred embodiment, each first and second circuit are independently controlled. So, combined, the umbilical shown inFIG. 1 can deliver a total of 320 horsepower (238 kilowatts) at 20 miles to do work at that distance.
• FIG. 7 shows thecasing hanger130. The casing hanger was identified withelement130 inFIG. 6. A portion of the casing hanger is surrounded by casinghanger seal132. The casing hanger seal was also previously identified withelement132 inFIG. 6.
• Theexpandable casing126 shown inFIG. 6 is attached to thecasing hanger130. In one embodiment, the casing hanger is attached to the expandable casing by a threaded joint. In this embodiment, that threaded joint appears at end ofcasing hanger222, although the threads on the casing hanger are not shown inFIG. 7 for simplicity. The opposite end of the casing hanger is shown aselement223. In another preferred embodiment, the casing hanger can be manufactured integral with the expandable casing. Acement flowby port224 is used during the cementing process as further explained in relation toFIG. 10. The expandable hanger contact area is generally designated aselement226 inFIG. 7. The length of the expandable hanger contact area is designated by the legend L1 inFIG. 7.
• FIG. 8 shows more detail for the downhole pump motor assembly that is related toelement182 inFIG. 6.Elements180,184,186,188,190,192 and194 were previously identified inFIG. 6. Those same elements are related to the elements appearing in the following.
• FIG. 8 generally shows a downhole pump motor assembly identified aselement228 which is configured as a Smart Shuttle®. In one preferred embodiment, various parts from REDA are used to make a downholepump motor assembly182. REDA may be located as defined above. In the embodiment,element230 is a REDA protector for a bottom drive motor that is 5.4 inches OD, and 4.5 feet long. In this embodiment,element232 is afirst REDA 4 pole, 80 horsepower, electric motor requiring 1250 volts at 45 amps that runs at the nominal RPM of 1700 RPM that is 5.4 inches OD and 31.5 inches long.Element234 is a power cable providing electrical power to the downholepump motor assembly228. In this embodiment,element236 is asecond REDA 4 pole, 80 horsepower, electric motor requiring 1250 volts at 45 amps that runs at the nominal RPM of 1700 RPM that is 5.4 inches OD and 31.5 inches long.Element238 is a REDA universal motor base part number UMB-B1 for a bottom drive motor that is 5.4 inches OD and 1.7 feet long.Element240 is REDA gearbox protector part number BSBSB having 4 mechanical seals that is 5.4 inches OD and 10.6 feet long.Element242 is a REDA gearbox having a 4:1 gear reduction that is 6.8 inches OD and 10.9 feet long.Element244 is a Netzsch flexible shaft that is 7.87 inches OD and 10 feet long. Netzsch Oilfield Products is located at 119 Pickering Way, Exton, Pa. 19341, having the telephone number of (610) 363-8010, that has the website of www.netzchusa.com.Element248 is a Netzsch progressing cavity pump part number NM090*3L (EX) that is 7.87 inches OD and 11.8 feet long.Element248 is a crossover.Element250 is 4 inch tubing.Element252 is a Smart Shuttle seal.Element254 is an intake port into the Netzsch progressing cavity pump.Element256 is the discharge outlet from the Netzsch progressing cavity pump.
• The downhole pump motor assembly identified aselement228 needs a cablehead, centralizers, bypass valves, sensors, and intelligent controls to make one embodiment of a Smart Shuttle®. Such a Smart Shuttle will have a minimum pulling force of 4400 lbs, a maximum transit speed of 11 feet per second, that operates within 9⅝ inch O.D., 53.5 lb/foot casing. It has variable speed, is reversible, and has high speed bidirctional communications with instrumentation on the surface of the earth.
• FIG. 9 shows a subterranean electric drilling machine boring a new borehole from an offshore platform.FIG. 9 shows the subterraneanelectric drilling machine94 deployed within a previously installedborehole casing96 that is surrounded by existingdownhole cement98 that is in the process of drilling thenew borehole104 intogeological formation102, which elements were previously defined in relation toFIG. 6. Also shown inFIG. 9 is theexpandable casing126 that was also defined inFIG. 6. The subterranean electric drilling machine was thoroughly described inFIG. 6.
• InFIG. 9, anoffshore platform258 has ahoisting mechanism260 that is surrounded byocean262 that is attached to the bottom of theocean264. The ocean surface is shown byelement265.Riser266 is attached to blow-out preventer268.Surface casing270 is cemented into place withcement272. A section of previously installedcasing274 extends from the lower portion of thesurface casing270 to the previously installedborehole casing96. Thebroken line276 shows that the section of previously installedcasing274 can be many thousands of feet long. Previously installedcasing274 may actually be comprised of different lengths of casings having different inside diameters, outside diameters, and weights, but that detail is not shown inFIG. 9 in the interest of simplicity. Other conductor pipes, surface casings, intermediate casings, liner strings, or other pipes may be present, but they are not shown for simplicity. The upper portion of the umbilical278 proceeds to the stripper heads and surface blow-out preventers (BOP's), then proceeds tolocation70 inFIG. 5, and is then wound up on theumbilical carousel64 inFIG. 5. In this preferred embodiment, the computerized uphole management system for the umbilical as shownFIG. 5 is mounted on the offshore platform. InFIG. 9, other geological formations represented byelement280 are located abovegeological formation102. Other geological formations represented byelement282 are belowgeological formation102.
• InFIG. 9, the directions of the arrows show the mud flow. Fresh mud travels from the surface down the annuli between the well casing and the umbilical designated byelement212.Element212 was previously defined inFIG. 6. Cuttings laden mud returns to theoffshore platform258 on the interior of the umbilical283. The arrows show the mud flow pattern in the vicinity of the subterraneanelectric drilling machine94. This mud flow system is called a “reverse mud flow system”. This reverse mud flow system will keep the cuttings within the umbilical, therefore preventing any debris from accumulating in the annuli between the well casing and the umbilical that might prevent the subterranean electric drilling machine from returning to the offshore platform. In other preferred embodiments, the mud flow can be opposite—namely, clean mud flows down the interior of the umbilical, and cuttings laden mud flows up the annuli between the well casing and the umbilical.
• For the purposes of this invention, the phrase “offshore platform” includes the following: (a) bottom anchored structures that include artificial islands, gravity based structures, piled truss structures (conventional platforms), and compliant towers; (b) mobile-bottom sitting structures that include submersible structures including submersible barges (in swampy and shallow water areas), mobile gravity base structures (like the concrete islands in the Arctic) and jackup platforms; (c) floating-permanently moored structures including the tension leg platforms (TLP), the SPAR and Semisubmersible, and the Floating Production, Storage, and offloading structures (FPSO); and (d) floating-mobile structures such as shipshape-like drilling rigs, semisubmersibles that are catenary moored, and barges.
• It is helpful to review howFIGS. 6,7,8, and9 relate to the drilling process. As was shown inFIG. 6, theexpandable casing126 in its un-expanded state is carried into the hole as an outer sheath overrotary shaft125 and associated components, which may also be called a “drilling work string”. At the lower end of that borehole assembly (“BHA”) is anchored into the casing. In one preferred embodiment, the string of expandable casing is 3,000 ft long.
• Starting with the drilling machine out of the hole, the expandable casing is run in and suspended in the wellbore from the surface. The top of the casing has an expandable casing hanger installed.FIG. 7 shows the expandable casing hanger. Next, the bottom hole assembly is run through the casing and secured into the bottom joint of the unexpanded suspended casing. The casinghanger setting tool134 is secured into thecasing hanger130 together with the first and second anchor and weight onbit mechanisms140 and142, the downholeelectric motor114, and the remaining portions of the subterraneanelectric drilling machine94. The entire subterranean electric drilling machine and expandable casing is then tripped to the bottom of the well. Drilling the next section of the well continues until sufficient hole for the expandable casing has been drilled. With the expandable casing in place, the casing hanger setting tool expands and locks the unexpanded length of expandable casing in the hole. The subterraneanelectric drilling machine94 then releases from the casing and is recovered from the well.
• In one preferred embodiment, the casinghanger setting tool134 is a packer-like assembly located beneath the downholeelectric motor114. The casing hanger setting tool initially expands with sufficient pressure to secure the casing to the non-rotating housing that is connected to the swivel andseal unit124 that centralizes the casing. Once the new hole has been drilled, and thecasing hanger130 is in proper setting position, much higher pressure is pumped into the casing hanger setting tool to plastically expand the hanger and cold forge the hanger into the previously installedborehole casing96. As an example of this process, various manufacturers connect pipeline repair tools to pipeline ends and connect wellheads to the top of casing strings with this type of “cold forge” process. The cement flowby ports of the casing hanger are left open for circulation of cement behind the casing. When the expandable casing is later expanded, these holes are sealed through contact with overlap in the previous casing string. The casing hanger seal and cement help ensure a leak tight seal.
• In one preferred embodiment of the invention, the subterranean electric drilling machine is used to accomplish the many purposes including the following: (a) drill thenew borehole104; (b) convey into the well theexpandable casing126; and (c) then using the casinghanger setting tool134, the casing hanger is expanded into the previously installedborehole casing96. Thereafter, the subterranean electric drilling machine releases from the casing hanger, thereby leaving the casing hanger and theexpandable casing126 in its unexpanded state in the well, and the subterranean electric drilling machine is then removed from the well.
• Thereafter, another tool called a subterranean liner expansion tool is conveyed into the wellbore. In one preferred embodiment, the subterranean liner expansion tool is labeled withelement284 inFIG. 10.FIG. 10 shows the previously installedborehole casing96, the existingdownhole cement98, thenew borehole104, a portion thecasing hanger130 after the above expansion steps have been performed in (c) above, oneend222 of the casing hanger shown inFIG. 7, and theother end223 of the casing hanger shown in that figure.Cement flowby port224 is also shown.
• The subterraneanliner expansion tool284 is used in a two step process. First, the cement is injected behind the unexpanded expandable casing. That process is shown inFIG. 10. Second, the expandable casing is expanded. That process is shown inFIG. 11. Thereafter, the subterranean liner expansion tool is removed from the well, and the well is either completed, or the well is further extended using the methods and apparatus described above.
• InFIG. 10, the subterraneanliner expansion tool284 is positioned withinunexpanded casing286. Counter-rotating roller casing expander tool is generally shown as numeral288 inFIG. 10. In one preferred embodiment, clockwise rotatingroller assembly290 is on the uphole side of the counter-rotating roller casing expander tool. It hasindividual rollers292,294,296, and298. In this embodiment, counter-clockwise rotatingroller assembly300 is on the downhole side counter-rotating roller casing expander tool. It hasindividual rollers302,304,306 and308. Electrically powered hydraulic systems within the counter-rotating roller casing expander tool are capable of loading the individual rollers against the interior of the expandable casing. In one preferred embodiment, several of the rollers, such asroller304, are canted through the angel θ. In one preferred embodiment, the rollers are hydraulically loaded and are canted to advance through the expandable casing as the rotating roller assembles290 and300 rotate in their respective directions. Electrically powered systems within the counter-rotating roller casing expander tool are then capable of rotating the appropriate elements of each rotating roller assembly. InFIG. 10, the rollers are in their fully retracted position. The electric motor and related hydraulics for the counter-rotating roller casing expander tool are located withinhousing310. That electric motor is labeled with legend312, and the related hydraulics is labeled with legend314, although those are not shown inFIG. 10 for simplicity.
• Thetorque resistance section316 is a component of the counter-rotating roller casing expander. It haslongitudinal rollers318 and320. An electric motor322 and associated hydraulics324 are located withintorque resistance section316 to properly actuate thelongitudinal rollers318 and320. However, elements322 and324 are not shown inFIG. 10 for the purposes of simplicity. The purpose of thetorques resistance section316 is to prevent any unbalanced torque resulting from the operation of the subterranean liner expansion tool that might cause the remainder of the downhole tool attached to the umbilical116 to twist, thereby possibly breaking the umbilical. Breaking the umbilical downhole would be a catastrophic failure, although the tool can be retrieved using techniques to be described below.
• Various electrical wires and connectors along the length of the subterranean liner expansion tool conduct electrical power from the umbilical116 to the counter-rotating roller casing expander tool288 (which are designated figuratively by element326 which are not shown inFIG. 6 for the purposes of brevity). Sensors within the counter-rotating roller casing expander tool provide measurements such as the force delivered by the rollers to the casing, the position of the rollers, etc., which measurements are suitably is digitized and sent thorough suitable electrical circuitry and connectors along the length of subterranean liner expansion tool (designated figuratively by element328 which is not shown inFIG. 10 for brevity), which digital information is then sent uphole through the fiberoptical cable14 within the umbilical116 in the form of suitable light pulses. Commands from the surface are also send downhole through the same bidirectional communications path. For example, commands to change the contact of the rollers, or expand the rollers outward to expand the casing may be sent downhole through this bidirectional communications path.
• FIG. 10 further shows progressingcavity pump180 that is driven by a downholepump motor assembly182 andshroud180, which were previously described inFIG. 6.Inflatable cement seal330 is inflated during cementing operations.
• In the preferred embodiment shown inFIG. 10, cement from the surface proceeds through umbilical116; through umbilical mud valve204 (which is used for both mud and cementing purposes); to thecross-over system216 and intoregion332; through thecement flowby port224; throughregion334 between the previously installedborehole casing96 and the exterior of theunexpanded casing286; then intoregion336 between the exterior of the unexpanded casing and the ID of the new borehole that labeled withelement338. Themud valve204 has a total of three positions: (a) open, namely it allows cement to flow through as shown inFIG. 10; (b) stop (not allow any cement to flow straight through); and (c) vent to the annulus between the umbilical116 and the ID of the previously installed casing so that cement can be cleaned from within the umbilical (which state is not shown inFIG. 10 for simplicity). The region between the umbilical116 and the ID of the previously installed casing is shown aelement212 inFIG. 6, although that particular element is not shown inFIG. 10 for simplicity (because of the large number of labeled elements in that vicinity ofFIG. 10).
• InFIG. 10, the position of the “front” of the cement flow is shown byelement340. Sufficient cement is introduced intoregion336 so that when theunexpanded casing286 is expanded in the next step (as explained below), then the well is properly cemented in place. Various sensors within the subterranean liner expansion tool provide data that allows thecomputer system26 on the offshore platform in this embodiment to determine the proper amount of cement to be sent downhole that at least partially fillsregion342 that is located between the exterior of theunexpanded casing286 and OD of thenew borehole338 which is not filled with cement inFIG. 10. The overlapping region between the old cement and the new cement that has not set up inFIG. 10 is shown aselement344. The new cement is now allowed to set up as shown inFIG. 10. However, there is old cement that is hardened inFIG. 10 such as the old cement behind thecasing hanger130 that is identified withnumeral345.
• The subterraneanliner expansion tool284 is comprised of a number of components including the counter-rotating rollercasing expander tool284 and the Smart Shuttle®. The subterranean liner expansion tool is transported downhole by the Smart Shuttle® which is comprised of components including theSmart Shuttles seal210, the progressingcavity pump180, the downholepump motor assembly182, and theshroud180 which have been previously described in relation toFIG. 6. The Smart Shuttle also returns the subterranean liner expansion tool to the offshore platform in this preferred embodiment.
• In a preferred embodiment of the invention shown inFIG. 10, theunexpended casing286 is 3,000 feet long, has a weight of approximately 40 lbs/foot, and has an unexpanded OD of approximately 8.0 inches OD. In a preferred embodiment shown inFIG. 10, the previously installedborehole casing96 is a 9⅝ inch OD casing having a weight of approximately 40 lbs/foot.
• FIG. 11 shows the subterraneanliner expansion tool284. Portions of the subterranean liner expansion tool are shown inFIG. 11 including the counter-rotating rollercasing expander tool288, thetorque resistance section316, and the progressingcavity pump180 that is attached to the downholepump motor assembly182.
• After cementing was completed inFIG. 10, the subterranean liner expansion tool is pulled up vertically above thecasing hanger130. Then the rollers of the clockwiserotating roller assembly290 the counter-clockwiserotating roller assembly300 are placed in their extended positions. Then counter-rotating rollercasing expander tool288 is suitably energized, and it begins to expand the expandable casing on its downward travel (to the right-hand side ofFIG. 11) within the well.FIG. 11 shows the subterranean liner expansion tool in a location in the formation that is beyond the end of the previously installedcasing100 that is defined inFIG. 10.
• InFIG. 11, the expandable casing in its fully expandable form is shown atlocation348. InFIG. 11, the expandable casing in its unexpanded form is shown atlocation350. Cement surrounding the expandable casing in its fully expandable form is shown aselement352 inFIG. 11. Cement surrounding the expandable casing in its unexpanded form is shown aselement354 inFIG. 11. The counter-rotating rollercasing expander tool288 remains suitable energized, and it eventually completes the expansion of the expandable casing at some extreme distance in the well designed byelement356 inFIG. 11. Thereafter, theliner expansion tool284 is removed from the wellbore. Thereafter, the cement is allowed to cure. After the cement is cured, the well is completed to produce oil and gas using techniques and procedures typically used in the oil and gas industry or using those methods and apparatus described in the “SDCI IP”, entire copies of which are incorporated herein by reference.
• InFIG. 11, the expandable casing in its fully expandable form as shown atlocation348 can also be called equivalently a “liner” because of its attachment to the previously installedcasing96 inFIG. 10. Hence, the name “subterranean liner expansion tool”.
• FIG. 12 shows thecasing hanger130, acement flowby port224, the previously installedborehole casing96, andexpandable casing126 in its unexpanded form that is attached to the casing hanger at casinghanger end222. These elements have been previously defined inFIG. 6 and inFIG. 7.FIG. 12 shows the casing hanger after a portion of it has been expanded with the casing hanger setting tool. The state of thecasing hanger130 inFIG. 12 is similar to that shown inFIG. 10. The inside diameter of the previously installedborehole casing96 is shown inFIG. 12 by the legend ID2. The wall thickness of the previously installed borehole casing is identified by the legend WT2. The inside diameter of theexpandable casing126 in its unexpanded form is identified by the legend ID3. The wall thickness of the previously installed borehole casing is identified by the legend WT3. This is the configuration before the passage of the subterranean liner expansion tool.
• FIG. 13 provides a section view of the configuration of components shown inFIG. 12 after the passage by the subterranean liner expansion tool. Various elements onFIG. 13 have been previously described. In addition,element358 shows the expandable casing in its expanded state after the passage of the subterranean liner expansion tool. Various inside diameters are defined by legends ID2, ID4, and ID5. In general, ID2 will equal ID4 that will equal ID5. If this is the case, this is a true monobore well. However, there are limitations to the power of the subterranean liner expansion tool. So, if old hard cement is set up behind the overlapping portions of the previously installed casing in the location identified byelement360, the subterranean liner expansion tool may not have sufficient power to crush old hard cement and rock behind that particular location. Such a location is identified byelement345 inFIG. 10. In such event, ID4 would be less than ID2 by as much as 2 times the dimension of WT2 inFIG. 12. This extra thickness may persist for the length of the casing hanger L1 as shown inFIG. 7. Therefore, the installation described inFIG. 13 will provide either a monobore well, or a near-monobore well.
• In the following, there are different topics of interest related to the above described preferred embodiment. Subsection titles will be used for the purposes of clarity.
• FIG. 14 shows relevant parameters related to fluid flow rates through the umbilical. Umbilical fluid flow rates are sufficient to support drilling as shown inFIG. 9. One preferred embodiment uses a 4.5 inch ID pipe providing 173 gallons per minute (GPM) at a pressure of 1000 pounds per square inch (PSI) pressure loss over a 20 mile offset. Here, the “Pressure Loss” is 1000 PSI. Here, the “Flow Rate” is 173 gallons per minute. This was calculated using a Bingham Plastic mudflow model with 12 lb/gallon mud at a velocity of 3.5 feet per second (fps). This is a “Flow Velocity” of 3.5 feet per second. The umbilical geometry of 4.5 inches ID and 6.0 inches OD may be optimized under different situations as required. However, these particular dimensions are selected for a reverse flow mud system inside a 8.5 inch ID cased hole having a 20-mile offset. The Bingham Plastic mudflow model is described in detail in Section 8.2 entitled “Mathematical and Physical Models” of the book entitled “Petroleum Well Construction” by Michael J. Economides, Larry T. Watters, and Shari Dunn-Norman, John Wiley & Sons, New York, N.Y., 1998, an entire copy of which is incorporated herein by reference. An entire copy of the book referenced in the previous sentence is also incorporated herein by reference. In particular, please refer to Table 8-2 onpage 222 of the book for detailed algebraic equations related to the Bingham Plastic Model.
Tripping into the Well
• There are various constraints on how rapidly the subterranean electric drilling machine can enter the wellbore. Since the vertically suspended casing string and the subterranean electric drilling machine weight may be greater than can be safely run with the umbilical, the first anchor and weight on bit mechanism (AWOBM)140 and second anchor and weight on bit mechanism (AWOBM)142 as shown inFIG. 6 provide an anchor mechanism that acts as a “downhole hoist” to “walk” the casing vertically downhole and eventually into any horizontal section of the well. This “downhole hoist” is also called herein an “anchor mechanism” when used for this particular purpose. The subterranean electric drilling machine and its related anchor mechanism can be fielded from within a lubricator as is standard practice in the industry to maintain well pressure control. Once the downhole weight is within the capacity of the umbilical, use of the anchor mechanism is stopped and the casing load is transferred to the umbilical. The anchor means144 and146 and anchor means148 and150 as shown inFIG. 6 of the anchor mechanism are then collapsed for rapid transit to the bottom of the well. Further downhole travel of the casing and the subterranean electric drilling machine is accomplished by pumping mud into the annulus space between the well's installed casing and the umbilical. Pressure acting upon this annular piston area generates sufficient force to rapidly move the equipment downhole at about 2 fps in the 15 to 20 mile offset range. A 225,000 lb load with a 0.2 coefficient of friction requires approximately 1,600 psi differential pressure across Smart Shuttle seals (seeelement210 inFIG. 6). This pressure capability is obtained with multiple seals load-sharing the pressure. Motion cannot be accomplished without moving mud from below the drilling machine out of the well up through the umbilical ID. The pressure in the casing below the drilling machine (a sealed volume due to cementing) is approximately 3500 psi above static. The downhole mud pump may be used to assist in moving this required mudflow through the umbilical ID. For trip velocities in the range of 2 feet per second the surface mud pumps will need to provide 350 gallons per minute at 4600 pounds per square inch. At shorter distances with less pressure losses, the equipment may move faster (if surface mud pump volume capacity is available).
• FIG. 15 shows various parameters related to tripping the subterranean electric drilling machine and the expandable casing into the well. A 20 mile well is on the order of 100,000 feet. At this distance, and at 2 feet per second, the formation back pressure is 1000 PSI.
Tripping Out of the Well
• The subterraneanelectric drilling machine94 is tripped from the well with cuttings filled mud within the umbilical. Sufficient mudflow is pumped down the annulus between the umbilical and the uphole casing to fill the entire cased wellbore below the drilling machine. The maximum pressure the pump will provide this annulus is 5000 psi and at a 20 mile offset, the volume is limited to approximately 440 gallons per minute or a drilling machine trip speed of approximately 2.4 fps. Simultaneously, the surface linear umbilical traction unit pulls at approximately 12,500 lbs (to overcome the fluid flow drag upon the umbilical, the frictional umbilical drag and the frictional drag of the subterranean electric drilling machine and its seals).
• As the subterranean electric drilling machine moves up the wellbore and the annular fluid pressure losses become less, the maximum mud pump pressure no longer limits the trip speed. The limiting factor then becomes the mud volumes, which the mud pumps may provide. For these tripping purposes, a third surface mud pump may be used in another preferred embodiment. It will support higher speed trips and provide redundancies during other operations.
• Since all of the mud volumes pass through the downhole mud pump, an accurate metering of the mud volume and pressures is obtained throughout the trip. This keeps pressure off the open formation during trips out of the wellbore.
Surface Mud System
• A large volume of working mud is needed to manage the umbilical volume while tripping in the hole. For 20-mile offset operations, an active mud tank volume of 3500 barrels may be required. This is similar in capacity to those used in some large offshore drilling rigs.
• In one preferred embodiment, the installed casing is 8.5 inches ID, and the umbilical is a 6 inch OD umbilical with a 4.5 inch ID. During drilling operations, the maximum mud flow rate is 150 gallons per minute with a pressure drop of 825 pounds per square inch, which includes frictional losses only. During tripping out of the hole at 2.4 feet per second, the maximum mud flow rate is 422 gallons per minute with a pressure drop of 4,750 pounds per square inch. During running in the hole with casing at 2 feet per second, the maximum mud flow rate is 350 gallons per minute, with a pressure drop of 3600 pounds per square inch (with cement sealed on the bottom of the well).
• Thus, for the tripping out of the well, a minimum of two 750 hp surface mud pumps would be required. One pump is adequate for routine drilling operations. When the subterranean electric drilling machine is at a distance of 20 miles, approximately 14 hours are required to run into the hole, 12 hours are required to come out of the hole, and 11 hours are required for cuttings to circulate from the bottom of the hole to the surface. Therefore, accurate monitoring and management of mudflow and quality into and out of the well and umbilical both at the surface and downhole at the drilling machine is important for reliable well control.
The Drilling Operation
• When the subterranean drilling rig reaches the bottom of the hole, the high-speed bit may encounter cement within the bore of the cased hole. The anchor means144,146,148 and150 as shown inFIG. 6 are engaged, mud circulation started and the bit is rotated. Notice that downhole sensors monitor mudflow composition parameters to minimize circulation time for conditioning the hole. Weight on bit is applied and drilling moves forward out of the previously cased hole. Traditional steering mechanisms and MWD tools are used to guide forward progress of the bit through the formation. Directly behind this BHA is the unexpanded casing.
• The mudflow rates and the cutting solids this flow rate can transport out of the hole will limit drilling progress. For example, a drilled 12½ inch ID hole and a 4½ inch ID umbilical having an internal mud velocity of 3 feet per second carrying 6.5% solids will have a maximum penetration rate of 90 ft/hr.
• Significant information will be monitored and communicated real time to the surface for control of the operations. Some of the information includes:
(a) Weight on bit
• (b) Penetration rate
(c) Bit RPM
• (d) Bit power (determined from power consumed by the downholeelectric motor114 of the subterranean drilling machine)
  (e) Mud flow rate through bit (by monitoring throughput of the progressing cavity pump180)
  (f) Differential mud pressures across bit and to surface across umbilical
  (g) Mud quality sensors for entrained gas, cuttings loading, etc.
  (h) Mud temperatures
  (i) Basic operating parameters of the various subterranean electric drilling machine functions that include voltage, power, RPM, pressure, temperature, axial load in umbilical at the pump, etc. are all monitored in real time to verify equipment status.
• This monitoring will provide for efficient control of the downhole drilling operation. If additional information is required, in one preferred embodiment additional instrumentation or tools may be included in the umbilical at the various connection points (approximately every 5 miles). In one preferred embodiment, it is preferable to have remotely operated downhole BOP's. These devices are packer-like assemblies, which when inflated, anchor to the inside of the casing. An internal valve provides a well fluid isolation point.
• This extensive monitoring capability allows drilling operations to use under-balanced fluids, if beneficial to the well program. This equipment capability also allows for direct well control and production testing through the drilling machine.
• When the well has drilled forward to the casing point, pressuring the setting tool included in the subterranean electric drilling machine sets the expandable casing hanger. The success of the hanger setting operation may be load tested with the downhole hoist (which when used in this application is also called a “weight on bit mechanism”). Upon verification of a successful operation, the subterranean electric drilling machine releases from the casing and starts its trip from the well. This will leave the well ready for casing cementing and casing expansion.
• During all operations in a wellbore, the umbilical is maintained under tension between the downhole tools and the surface equipment. This permits rapid transit in the wellbore by preventing buckling. A constraint is that a minimum number of gentle bends should be included in the wellbore design. This constraint is similar to familiar drill pipe and coiled tubing operational constraints in current well operations. Selected means to provide such tension are shown inFIG. 5. The tension is monitored withcomputer system26 inFIG. 5.
• Several contingency operations are reviewed to illustrate the capabilities of the subterranean electric drilling system.
• The subterranean electric drilling machine can control the well and can control a well “kick”, or well kicks. In one preferred embodiment, the well uses a reverse circulation system. The first mud cuttings and bypass port (MCBP)164 and the second mud cutting andbypass port166 in of the subterranean electric drilling machine act as a packer within the well directing all returns to the umbilical. The umbilical has sufficient pressure rating to contain any kick and allow it to be circulated from the well. Instrumentation monitoring mud conditions downhole should provide early indication of developing well control problems.
• The subterranean electric drilling machine can survive n open hole collapse. The well is drilled with unexpanded casing over the drilling work string (that iselement125 inFIG. 6). Should the formation collapse on the casing, the subterranean electric drilling machine is withdrawn through the unexpanded casing. The casing may subsequently be expanded and drilling operations resumed.
• The subterranean electric drilling machine can survive a downhole blackout of power. Assume the failure is in the power transmission or control system during a tripping operation. The umbilical and surface traction winch have sufficient power to pull the dead equipment from the wellbore. Surface pumps would continue to provide mud for displacement replacement. With care, mud pressure below the subterranean electric drilling machine may be used to reduce the load required to pull the machine from the well.
• If the failure occurs when the drilling machine is anchored and making hole, then a release between the downhole mud pump and the anchor means of the drilling machine is actuated. That disconnect occurs between the female side of universal mud andelectrical connector176 and the male side of universal mud andelectrical connector178 as shown inFIG. 6. In one preferred embodiment, the release may be triggered with an “over-pull” or operation may be via pumping a dart or ball down the umbilical. Once the release is actuated, the drilling machine controls, and mud pump assembly may be pulled “dead” from the well. Once the fault is isolated and repaired, the recovered equipment is run back into the well where it connects with the drilling equipment left in the hole. The Smart Shuttle portion of the subterranean electric drilling makes this reconnection. Regaining control of the equipment allows either drilling operations to proceed or for the equipment to be recovered from the well.
The Well Construction Process
• Drilling and casing operations in the preferred embodiment is a two-trip process. The drilling equipment defined above (the subterranean electric drilling machine) is used to drill the hole, position and anchor the casing (but not expand it) within the hole. The casing is left in position ready for cementing operations (if required) and casing expansion to its final installed dimension is accomplished with the use of a second tool system (the subterranean liner expansion tool).
• In this preferred embodiment, the new expandable casing is 3,000 feet long, 54 lbs/ft, and has an unexpanded OD of 8.0 inches OD. The downhole casing hanger and the casing string are then suspended from the surface rig floor. The bottom hole assembly (BHA) is then made up and run into the casing string. In one preferred embodiment, the centralizing casing hanger setting tool is used to lock the casing and drilling equipment together. Next the rotary motor and the anchor mechanism are added to the assembly together with the downhole mud pump that may be used as a Smart Shuttle.
• This described equipment is all long and heavy. It is handled as major assemblies with quick connection devices between each assembly. The estimated size and weight of various components appear below in the following.
• The bit is about 2 feet long, and weighs 500 lbs in air. The MWD tools are 40 feet long and weigh about 1,200 lbs in air. The rotary steering tool is about 30 feet long, and weighs 1,500 lbs in air. The rotary shaft (element125 inFIG. 6) also called the “drilling work string” or simply “drill pipe”, is about 3,000 feet long and weighs 28,500 lbs in air. The expandable casing has a weight of 54 lbs/ft, is about 3,000 feet long, and weighs 162,000 lbs in air. The rotary section and anchor section of the subterranean electric drilling machine (that includeselements114,140 and142 inFIG. 6) is about 120 feet long and weights 2,800 lbs. The downhole mud pump section of the subterranean electric drilling machine (includingelements180,196, and214 inFIG. 6) is about 122 feet long and weighs about 3,900 lbs in air. Any separate control module associated with the subterranean electric drilling machine is about 20 feet long and has a weight of 4,000 lbs. So, the total length of the assembly is about 3,334 feet long that weighs about 200,800 lbs in air.
Cementing and Expanding the Casing
• In this preferred embodiment of the invention, subterraneanliner expansion tool284 inFIG. 10 installs the cement and expands the monobore casing in the well. This approach was selected to simplify the subterranean electric drilling machine and to provide operational flexibility when performing these monobore well construction operations.
• The subterranean liner expansion tool has two basic functions. The first is to cement the casing in the well (if required). In one embodiment, this is accomplished through a 2 inch cementing line in a 3½ inch OD umbilical. Unlike the subterranean electric drilling machine when attached to casing, the Smart Shuttle at speeds up to 10 feet per second pulls this umbilical into the well. The Smart Shuttle operation of the liner expansion tool requires that theinflatable cement seal330 is collapsed, and then fluids are pumped from the downhole side of the SmartShuttle® seal210 to the uphole side of that seal as has been previously described. To cement the well,inflatable cement seal330 is inflated. This cement seal is also called a straddle seal (with one side being inflatable) on the tool's outside diameter that ensures the fluid connection between the umbilical and the cement ports in the casing hanger. Once the tool is in place, cement is circulated into the annulus space behind the unexpanded casing. Adequate instrumentation monitors cement placement, volume and Smart Shuttle location and reports all of these monitored parameters to the surface.
• The second function of the subterranean liner expansion tool is to expand the casing to its final operating size. The roller mechanisms for this task have already been described in relation toFIG. 10. Rollers provide power, control and reversibility. If the casing were expanded with internal pressure, it would lack any expansion control—for example, if the hole diameter were irregular, then the casing expansion would be irregular as well. Expansion dies have the problem of being a one shot, one size expansion process. Internal casing rollers have experience in buckled casing repair tools and in anchoring casing inside Unibore wellheads. Weatherford has developed a one step expansion tool for expanding casing that is featured on their website. Weatherford International, Inc. may be reached at 515 Post Oak Blvd,Suite 600, Houston, Tex. 77027, having the telephone number of (713) 693-4000, that has the website of www.weatherford.com. InFIG. 10, the counter-rotating rollercasing expander tool288 has contra-rotating rollers to minimize the tool's torque that has to be externally reacted while expanding the casing. Thelongitudinal rollers318 and320 inFIG. 10 provide for this torque reaction. As previously described, a downhole motor powered with a separate electrical circuit from the surface provides the necessary rotary power.
• In a preferred embodiment, the surface equipment is similar in arrangement to the drilling machine system. However, this equipment may be smaller as the umbilical OD may be chosen to be 3½ inches OD.
• As described earlier, in one mode of operation of the subterranean electric drilling machine, it acts like a Smart Shuttle. The Smart Shuttle will be used to pump the umbilical and the subterranean liner expansion tool to the downhole worksite. The Smart Shuttle works by pumping fluid from one side of the seals to the other with an electric powered progressive cavity pump (PCP) (or any positive displacement pump). At relative low differential pressures, large axial forces (approximately 4,000 lbs net) are generated that are sufficient to pull the tool and umbilical into the hole. Top-hole speeds are the maximum design speed of 10 fps. At extreme offsets, the speed will be slower (2.5 feet per second) due to fluid drag force on the umbilical, which will be proportional to the transit speed.
• The Smart Shuttle system is equipped with sensors to detect location and to easily position the tools straddle seals across the casing hanger of the last casing string. Once in position, the inflatable seal is inflated and circulation through the hole-casing annulus is confirmed. This may be accomplished by pumping from the surface or by using the Smart Shuttle pump to circulate the area. Cement will be spotted into the annulus and the casing will be expanded prior to the cement hardening.
• FIG. 10 illustrates the subterranean liner expansion tool with cement being injected from the surface through the umbilical. Approximately 69 gallons per minute will flow at 100,000 ft with a pressure loss of about 9,000 pounds per square inch. Thus, the cementing pump will have to deliver at 10,000 pounds per square inch at these rates. It will require 240 minutes for the cement to be delivered at 100,000 ft from the surface and then another 77 minutes to spot approximately 126 barrels of cement into the hole-casing annulus space. When operating at these large offsets, managing the setting time of the cement and the required volume of cement is important.
• Tracers may be added to the fluid pads before and following the cement as it is pumped into the umbilical. Sensors located on the subterranean electric drilling machine will verify when the cement is passing these downhole sensor locations. This will help accurately spot cement into the well. Once the cement is out of the umbilical, a bypass valve is opened and mud is circulated through the annulus to clear the umbilical.
• Some casing may not require to be cemented into the hole. It may be possible that the casing can be expanded into the wall of the hole with sufficient pressure that the residual contact stress between the rock and expanded casing are sufficient to form an axial fluid seal. This avoids the cementing step and simplifies operations. However, it places a significant load upon the casing expansion rollers.
• Once the cement is in position within the hole-casing annulus, theinflatable cement seal330 is deflated and the Smart Shuttle pulls the expansion tool back into the previously cased wellbore. The counter-rotating roller casing expander tool is energized, and its roller engage the casing ID by expanding until contact with the casing is established. Rotation of the rollers is begun and the tool slowly moves forward. Forward motion is provided by the slight canted angle of the rollers, which screw the expander into the casing hanger and pipe. This canted angle is shown as the angle θ inFIG. 10. In one preferred embodiment, the counter-rotating roller casing expander tool has sufficient strength to expand the casing hanger and the previously set casing back into the formation to provide a smooth casing ID. This process is illustrated inFIGS. 12 and 13.FIG. 12 shows the casing hanger area prior to tool's passage andFIG. 13 illustrates this same region after the tool has passed. The subterranean liner expansion tool has to have sufficient strength to expand the two casing strings back into the formation rocks.
• The subterranean liner expansion tool continues expanding the casing to the bottom of the string. The process of expanding the casing will reposition the cement that is in the annuli. It will be extruded along the reducing annuli until the cement reaches the end of the casing where excess will flow into the uncased hole below the expansion machine. Once the casing has been fully expanded, the rollers of the subterranean liner expansion tool are collapsed to their small transport size and the Smart Shuttle and surface traction winch are used to bring the tool to the surface. This leaves the hole ready for the next drilling cycle.
• Drilling and monobore casing operations continue until the well reaches the target reservoir. It is then possible to drill lateral drainholes (using a similar process) or a single large bore completion may be made.
• There are various methods to handle contingencies with the subterranean liner expansion tool. Similar to the subterranean electric drilling machine, considerable flexibility exists in the cementing and expansion tool concepts to handle most contingencies. A few of these contingencies illustrate this capability.
• Suppose the power to the subterranean liner expansion tool is cut off during a tip into the well. A bypass valve around the Smart Shuttle pump will open and allow the tool to be pulled from the wellbore using the surface linear winch and the strength of the umbilical. Alternatively, in some wells, it may be possible to pump mud down the cement line in the umbilical and apply pressure below the Smart Shuttle to assist in its retrieval.
• Suppose there is a loss of power with cement in the umbilical. Then, a downhole bypass valve will open connecting the umbilical bore with the cased well annulus. Mud pumps may then be used to flow the cement to the surface.
• Suppose the subterranean liner expansion tool fails without expanding the entire casing string. The tool is then recovered and the cement in the well annulus is assumed to harden. The next drilling operation will be to mill out of the wellbore and sidetrack to resume drilling to target.
• Suppose the expansion strength of the subterranean liner expansion tool is not sufficient to expand the casing hanger to a full bore ID. The subterranean liner expansion tool has the capability of operating at various diameters. It will expand the casing to gage diameter where ever possible. Some areas, (like the casing hanger area) may not achieve gage—especially if the formation is exceptionally hard/strong. The under gage diameter is not desirable, but not a significant problem as all of the tool systems should pass through this reduced diameter. Should it not be possible to achieve the minimum gage diameter, then a mill may be used to increase inside diameter as a last resort.
Casing Flotation Techniques
• Casing flotation techniques may be used to dramatically reduce the well annuli pressure required to pump casing into the well or reduce the required downhole hoist capacity. Air or nitrogen may be enclosed within the casing at the surface to reduce its apparent weight in mud during running operations. Once on bottom, the near buoyant casing would be flooded and filled with mud so that operations as previously described would continue. This and other related weight saving concepts have the potential to reduce the well annuli running pressure or downhole hoist capacity by 90% as compared to the loads identified above in the section entitled “The Well Construction Process”. This capability allows much longer and/or heavier strings of casing to be optionally run.
• Casing flotation techniques will not have an impact upon the umbilicals design criteria. The umbilical's internal working pressure defines its required axial strength. A 10,000 psi internal pressure for well control requires an umbilical axial load strength of approximately 160,000 lbs to resist the surface pressure effects.
Alternative Embodiments of Drilling Systems
• InFIG. 6, first anchor and weight on bit mechanism (AWOBM)140 and second anchor and weight on bit mechanism (AWOBM)142 are an example of “anchors” or “anchor means”. In the following summary, the term “Anchor Means” may be capitalized.
• InFIG. 6, theexpandable casing126 is being “pushed” deeper into the wellbore by the anchor means. Therefore, this configuration is called a “Drill & Push” configuration. In this situation, the anchor means are on the uphole side of the subterranean electric drilling machine. On the other-hand, if the anchor means were instead on the downhole side of the subterranean electric drilling machine, then this configuration would be called a “Drill & Drag” configuration.
• InFIG. 6, the anchor means are located on the inside of the previously installedborehole casing96. In this configuration, the anchor means are located within the “Wellbore”. On the other-hand, if the anchor means are instead located within thenew borehole104, then the anchor means are located in the “Open-Hole”.
• InFIG. 6, the downholeelectric motor114 rotates therotary shaft125 that is also called the “drilling work string” or simply the “Drill Pipe”. InFIG. 6, the downhole electric motor rotates the Drill Pipe. Therefore, the “rotary means”, inFIG. 6 is described by the following: “Rotates Drill Pipe”. InFIG. 6, theexpandable pipe126 is not rotated. However, there are other configurations of the rotary means including: “Rotates Drill Pipe and Casing”, and “In Open Hole Rotates Bit”. In the below defined list of different preferred embodiments, the term “rotary means” is capitalized as “Rotary Means”.
• InFIG. 6, theexpandable casing126 is not rotated. Therefore, in this configuration, the expandable casing is “Non-Rotating”. In other preferred embodiments, the expandable casing can be rotated by the rotary means. In this configuration, the expandable pipe is “Rotated”.
• InFIG. 6, the progressingcavity pump180 is driven by a downhole pump motor assembly generally designated byelement182 that comprises the mud pump, or “Mud Pump” inFIG. 6. In this preferred embodiment, the Mud Pump is located within the Wellbore.
• Accordingly, the preferred embodiment shown inFIG. 6 can be described as follows (Preferred Embodiment “A”):
• Arrangement: Drill & Push
• Anchor Means In Wellbore
• Mud Pump In Wellbore
• Rotary Means Rotates Drill Pipe
• Expandable Casing Non-Rotating
• Comments: Preferred Embodiment shown inFIG. 6.
• Accordingly, another preferred embodiment of the invention may be succinctly described as follows (Preferred Embodiment “B”):
• Arrangement: Drill & Push
• Anchor Means In Wellbore
• Mud Pump In Wellbore
• Rotary Means Rotates Drill Pipe and Expandable Casing
• Expandable Casing Rotating
• Comments: This requires higher rotary torque than Preferred Embodiment “A”.
• Accordingly, another preferred embodiment of the invention may be succinctly described as follows (Preferred Embodiment “C”):
• Arrangement: Drill & Drag
• Anchor Means In Open Hole
• Mud Pump In Wellbore
• Rotary Means In Open Hole, Rotates Drill Bit
• Expandable Casing Non-Rotating, Drags Behind Anchor Means
• Comments: This requires stable formations for Open Hole Anchor Means.
• Accordingly, another preferred embodiment of the invention may be succinctly described as follows (Preferred Embodiment “D”):
• Arrangement: “Drainhole Drilling”
• Anchor Means In Wellbore
• Mud Pump In Wellbore
• Rotary Means Rotates Drill Pipe
• Expandable Casing Non-Rotating
• Comments: Similar to Preferred Embodiment “A”, except smaller diameters of expandable casing used.
• In the above, Preferred Embodiment “C” is further described in the following document: U.S. Disclosure Document No. 494374 filed on May 26, 2001 that is entitled in part “Continuous Casting Boring Machine”, an entire copy of which is incorporated herein by reference.
• In the above, Preferred Embodiment “D” is further described in the following document: U.S. Disclosure Document No. 495112 filed on Jun. 11, 2001 that is entitled in part “Liner/Drainhole Drilling Machine”, an entire copy of which is incorporated herein by reference.
• The subterranean electric drilling machine has been illustrated performing hydrocarbon drilling applications. However, there are other preferred embodiments of the invention. The subterranean electric drilling machine has the capability of performing directional drilling over large distances both onshore and offshore. This includes drilling pipelines under large and deep rivers, across large topographical features like cliffs or subsea escarpments. Other applications for the subterranean electric drilling machine include near surface drilling in urban areas for installation or replacement of utilities like water lines, gas mains, sewers, storm drains, underground power lines, and communication lines, including broadband cables and fiber optic cables. The selected drill bit would be sized for the application. These preferred embodiments are not further described herein in the interests of brevity.
• FIG. 16 is similar toFIG. 9, except here the well is being drilled from an onshore wellsite. Subterraneanelectric drilling machine94 is disposed within a previously installedborehole casing362 that is surrounded by existingdownhole cement364. The subterraneanelectric drilling machine94 was described in relation toFIG. 6. The subterranean electric drilling machine is in the process of drilling anew borehole366 intogeological formation368.Expandable casing370 is carried into the new borehole by the subterranean electric drilling machine. Umbilical372 connects the subterranean electric drilling machine to a land-baseddrill center374 that has the hoist, the computer systems, the umbilical carousel, etc.Surface casing376 is surrounded bycement378. The bottom of the surface casing is connected to previously installedcasing362 by casingstring380. Theocean382 hasocean surface384 andocean bottom386. Here, the new borehole is being drilled beneath the ocean from a land-based drill center. Theland388 joins the ocean at abeach390.
• FIG. 17 is similar toFIG. 9 andFIG. 16, except here the well is being drilled from a land based drill site. Subterraneanelectric drilling machine94 is disposed within a previously installedborehole casing392 that is surrounded by existingdownhole cement394. The subterraneanelectric drilling machine94 was described in relation toFIG. 6. The subterranean electric drilling machine is in the process of drilling anew borehole396 intogeological formation398.Expandable casing400 is carried into the new borehole by the subterranean electric drilling machine. Umbilical402 connects the subterranean electric drilling machine to the land based drill site generally designated byelement404. Shown figuratively are hoist406; the umbilical carousel, computers, etc.408; and another section of umbilical410.Element411 figuratively shows a lubricator.Surface casing412 is surrounded bycement414. The bottom of the surface casing is connected to previously installedcasing392 by casingstring416. The surface of the earth is identified byelement418.
• FIG. 18 shows a subterranean electric drilling machine420 that is drilling an open borehole in the earth. Element420 is called an open hole subterranean electric drilling machine.Electric motor422 turnsshaft424 that rotates therotary drill bit426 that drillsborehole428 ingeological formation430. First anchor and weight on bit mechanism (AWOBM)432 is connected to second anchor and weight on bit mechanism (AWOBM)434 byextensible shaft436, which elements comprise an anchor mechanism.Shaft438 connects the female side of universal mud andelectrical connector440 to the male side of universal mud andelectrical connector442. Progressingcavity pump444 is driven by itspump motor446.Inflatable seal448 surrounds the progressing cavity pump that makes a positive seal against the borehole wall ofgeological formation449. The progressing cavity pump hasinlet450 andoutlet452. Theinflatable seal448 and the progressing cavity pump form a Smart Shuttle that can be used to move the open hole subterranean electric drilling machine shown inFIG. 18 in and out of the hole.Centralizer454 is attached to the portions of the toolbody having electronics456 andbidirectional communications458 with the surface. Mud carrying umbilical460 is connected to thecable head462 that provides electrical power and mud to the open hole subterranean electric drilling machine. Mud from the surface through the umbilical proceeds down the interior of various elements of the drilling machine that are not shown for simplicity, and then mud laden cuttings return to the surface through theannulus464 between the borehole wall and the outside diameter of the umbilical. The arrows inFIG. 18 show the direction of mud flow. Theinflatable seal448 surrounding the progressing cavity pump is partially collapsed during actual drilling operations to allow the mud to pass. Theinflatable seal448 is inflated when quickly transporting the open hole subterranean electric drilling in and out of the well. In view of the detailed description provided inFIG. 6 and elsewhere, and in view of the description herein, it is now evident how the open hole subterranean electric drilling machine functions. Accordingly, no further detail will be presented here in the interests of brevity.
• FIG. 19 shows another subterraneanelectric drilling machine466 that is drilling an open borehole in the earth.Element466 is another embodiment of an open hole subterranean electric drilling machine called a “screw drive subterranean electric drilling machine”.FIG. 19 is similar toFIG. 18.Elements422,424,426,432,434,436,438,440 and442 have been defined in relation toFIG. 18.
• The fundamental change inFIG. 19 is that the form of the Smart Shuttle shown inFIG. 18 has been replaced by thescrew translator device468.Element470 has an electric motor472 (not shown for simplicity), related electronics, and bidirectional communications electronics. When electric motor472 rotates thescrew blades474, then friction against the mud in thehole476 causes thescrew translation device468 to translate within the hole (if the anchor means ofelements432 and434 are in their retracted positions). Reversing the rotation of the screw blades reverses the direction of translation within the borehole. The female side of universal mud andelectrical connector478 is attached to the male side of universal mud and electrical connector480, that is in turn connected to umbilical482, however, elements480 and482 are not shown inFIG. 19 for the purposes of simplicity.Centralizers 484 centralizeelement470 within thewellbore486. The arrows show the path of the mud flow during drilling operations. In view of the previous disclosure, it is evident how the screw drive subterranean electric drilling machine is used to drill thenew borehole488 in thegeological formation490.
• In another preferred embodiment inFIG. 19, thescrew blades474 have a variable pitch, where the distance between successive blades is a smaller distance to the right-hand side ofFIG. 19 than to the left-hand side ofFIG. 19. In yet another preferred embodiment, the pitch between thescrew blades474 is variable and controlled by thesurface computer system26. Various embodiments of the “screw drive subterranean electric drilling machine” are further described in U.S. Disclosure Document No. 494374 filed on May 26, 2001, that is entitled in part “Continuous Casting Boring Machine”, an entire copy of which is incorporated herein by reference.
• FIG. 20 shows a cross section of another embodiment of an umbilical used for subterranean electric drilling machines and for open hole subterranean electric drilling machines. A version ofFIG. 20 was originally filed in the U.S.P.T.O. on the date of Oct. 2, 2000 as a portion of U.S. Disclosure Document 480550. Umbilical492 contains at least one insulatedelectrical conductor494. Each such conductor haselectrical copper conductors496 encapsulated byelectrical insulation498. As shown inFIG. 20, there are a total of 8 such insulated electrical conductors. In one embodiment, the insulated electrical conductors may be chosen to be the same as shown inFIG. 1. Also shown is high speed bidirectional data communications means500, which may be a fiber optic cable or a coaxial cable. The insulated electrical conductors and the high speed bidirctional data communication means is encapsulated by firstcomposite material502. Secondcomposite material504 surrounds first composite material. As described above, the specific gravities ofcomposite materials502 and504 may be engineered so that the umbilical492 is substantially neutrally buoyant in wellbore fluids.
• In one preferred embodiment of the invention inFIG. 20, the secondcomposite material504 is chosen for its good strength, durability against abrasion in the well, and perhaps for its electrical insulation properties. In one embodiment ofFIG. 20, the first composite material is chosen so with a particular specific gravity such that the overall umbilical is neutrally buoyant in typical well fluids (in 12 lb per gallon mud, for example, or in salt water, as another example). As previously discussed, syntactic foam materials having silica microspheres as provided by the Cumming Corporation (www.emersoncumming.com) for such purposes. The details on pressure balanced silica microspheres in syntactic foam may be reviewed inAttachment 28 to the Provisional Patent Application No. 60/384,964 filed on Jun. 3, 2002 that is entitled “Umbilicals for Well Conveyance Systems and Additional Smart Shuttles and Related Drilling Systems”, an entire copy of which is incorporated herein by reference.
• Theinterior506 of the umbilical is used to provide drilling fluids or cement downhole as required. Therefore, different embodiments of umbilicals provide electric power downhole, bidirectional communications, and provide the ability to conduct fluids to and from the borehole, which are neutrally buoyant in the fluids present. Umbilicals handling well fluids are also useful with a number of well services including the use with straddle packers, injection tools, oil gas separators, flow line cleaning tools, valves, etc. In another preferred embodiment, the interior506 may be filled with composite materials to provide extra strength for certain applications that is also substantially neutrally buoyant.
• FIG. 21 shows yet another neutrally buoyant composite umbilical in 12 lb per gallon mud. Outer spoolablecomposite tubing508 has an OD shown by legend OD6, and has an ID shown by legend ID6. In a preferred embodiment, OD6 is equal to 1.75 inches O.D., and ID6 is equal to 1.25 inches I.D. In one preferred embodiment, the composite tubing is chosen to have a specific gravity of 1.50.
• Three each 0.355 inch O.D. insulated No. 4AWG Wires510,512 and514 are disposed within the I.D. of the spoolable composite tubing.Optical fiber516 is also disposed within the spoolable composite tubing. The remaining available volume within the spoolable composite518 is then filled with pressure balanced silica microspheres in syntactic foam that has a specific gravity of 0.60. A calculation shows that this umbilical in 12 lbs/gallon mud weighs −50 lbs for every 1,000 feet. Assuming a coefficient of friction of 0.2, at 20 miles the umbilical could pull back with a frictional force of 1,056 lbs. So, this umbilical is substantially neutrally buoyant (or simply “neutrally buoyant” as defined below).
• InFIG. 21, the insulated wire is rated at 14,000 volts. This particular wire is Part Number FEP4FLEXSC available through Allied Wire & Cable located in Bridgeport, Pa. This wire was previously described in relation toFIG. 1. As is evident from the discussion involvingFIG. 1, the three power conductors can provide 160 horsepower (119 kilowatts) at 20 miles to do work at that distance. No fluids are conducted down the interior of this umbilical generally designated byelement520 inFIG. 21. This umbilical is also useful for other applications to be discussed later.
• Selecting different specific gravities for the pressure balanced silica microspheres in syntactic foam that fills the volume within the spoolable composite518 allows different preferred embodiments to be designed to be neutrally buoyant within different well fluids having different densities. As a practical matter, an umbilical having a particular density will be used within a range of acceptable densities of well fluids.
• FIG. 22 is a schematic drawing that shows a ship performing subsea well servicing.Ship522 inocean524 possesses anumbilical carousel526 having umbilical528 that proceeds throughlubricator530 that housesSmart Shuttle532. Subsea well534 on theocean bottom535 hasmating equipment536 that mates tomating equipment538 of thelubricator530. The lubricator is guided into place by remotely operatedvehicle540 obtaining its power and communications from umbilical542. The umbilical carousel for umbilical542 is not shown for simplicity.
• Upon entering the subsea well, the Smart Shuttle is to proceed through the base of thelubricator544 and into the wellbore below (not shown inFIG. 22). There, the Smart Shuttle is to perform a well workover that requires fluids to be injected into formation such as acids. Umbilical528 may be selected to be a suitable umbilical including umbilical2 inFIG. 1, and umbilical492 inFIG. 20. Equipment resembling what is shown inFIG. 5 is on board the ship so that a computer system can control the workover operations.
• In this case, umbilical542 need not provide fluids to the remotely operatedvehicle540. Therefore, umbilical542 may be chosen from umbilicals that includes umbilical520 inFIG. 21. Equipment resembling what is shown inFIG. 5 is also onboard ship so that a computer system can control the remotely operatedvehicle540. The upper end of umbilical542 proceeding to its carousel is not shown on the left-hand side ofFIG. 22 for simplicity. In this case, the umbilical542 is designed to have any desired buoyancy in sea water, that specifically includes densities greater than sea water, as is conventional in the industry. The apparatus and methods to control the power and communications is similar to that shown inFIGS. 2,3,4 and5 and will not be repeated here for the purpose of brevity. In one preferred embodiment, over 60 kilowatts of power is provided by umbilical542 to remotely operatedvehicle540. This power is provided to the load of the remotely operated vehicle, which in several preferred embodiments, is an electric motor that drives a propeller that provides thrust for the remotely operated vehicle. For simplicity,FIG. 22 does not show a free floating remotely operated vehicle (ROV) tethered to the ship by a free floating umbilical.
• FIG. 23 is a schematic drawing similar toFIG. 22.FIG. 23 also shows a ship performing subsea well servicing.Ship546 inocean548 possesses a first umbilical carousel550 (not shown inFIG. 23 for simplicity) having umbilical552 that proceeds throughlubricator554 that housesSmart Shuttle556. Subsea well558 on theocean bottom560 hasmating equipment562 that mates tomating equipment564 of thelubricator554. The lubricator is guided into place by first remotely operatedvehicle566 that obtains its power and communications from umbilical568 that is deployed from second umbilical carousel570 (not shown inFIG. 23 for simplicity). In this case, the umbilical568 is designed to have any desired buoyancy in sea water, that specifically includes densities greater than sea water as is conventional in the industry. The upper end of umbilical568 proceeding to carousel570 near the top of the crane on the right-hand side ofFIG. 23 is not shown for simplicity.
• Upon entering the subsea well, the Smart Shuttle is to proceed through the base of thelubricator572 and into the wellbore below (not shown inFIG. 22). There, the Smart Shuttle is to perform a well workover that does not necessarily require fluids to be injected into formation. Therefore, umbilical552 may be selected to be a suitable umbilical including umbilical520 inFIG. 21. Equipment resembling what is shown inFIG. 5 is on board the ship so that a computer system can control the Smart Shuttle, and any equipment attached to the Smart Shuttle, during workover operations.
• In this case, umbilical568 need not provide fluids to first remotely operatedvehicle566. Therefore, umbilical568 may be chosen from umbilicals that includes umbilical520 inFIG. 21. Equipment resembling what is shown inFIG. 5 is also onboard ship so that a computer system can control first remotely operatedvehicle566. In this case, the umbilical568 is designed to have any desired buoyancy in sea water, that specifically includes densities greater than sea water as is conventional in the industry. The apparatus and methods to control the power and communications to first remotely operated vehicle are similar to that shown inFIGS. 2,3,4 and5 and will not be repeated here for the purpose of brevity.
• FIG. 23 shows second remotely operatedvehicle574 that obtains its power and communications from umbilical576 that is deployed from third umbilical carousel578 (not shown inFIG. 23 for simplicity). Second remotely operatedvehicle574 is to suitably attach to thesubsea well558 and is to remove fluids from the wellbore. Therefore, umbilical576 may be selected to be a suitable umbilical including umbilical2 inFIG. 1 and umbilical492 inFIG. 20. The upper end of umbilical576 proceeding to carousel578 near the top of the crane on the left-hand side ofFIG. 23 is not shown for simplicity. Equipment resembling what is shown inFIG. 5 is on board the ship so that a computer system can control the operation of second remotely operatedvehicle574. In this case, the umbilical576 is designed to have any desired buoyancy in sea water, that specifically includes densities greater than sea water as is conventional in the industry. In one preferred embodiment, over 60 kilowatts of power is provided by umbilical576 to remotely operatedvehicle574. This power is provided to the load of the remotely operated vehicle, which in several preferred embodiments, is an electric motor that drives a propeller that provides thrust for the remotely operated vehicle. In other embodiments, this power is provided to an electric motor that drives a downhole pump. For simplicity,FIG. 23 does not show a free floating remotely operated vehicle (ROV) tethered to the ship by a free floating umbilical.
• InFIGS. 22 and 23, the feedback control of the voltage, RPM, current, and other parameters of an electric motor within an remotely operated vehicle is accomplished by analogy to that disclosed in relation to the electric motor of the subterranean electric drilling machine. In the interests of brevity, this feedback control of remotely operated vehicles will not be further discussed.
• FIG. 24 shows one embodiment of the Smart Shuttles generally designated with the numeral580 that is located within a “pipe means”582 that includes a casing, drill pipe, tubing, etc. The Smart Shuttle is comprised of aprogressive cavity pump584 that has arotor586 andstator588 as is typical of such pumps. The progressive cavity pump is coupled togear box590 that is in turn coupled to the electricalsubmersible motor592, which in turn is connected toelectronics assembly594 having any downhole computer, the downhole sensors, and communications system, which in turn is connected by thequick change collar596 to theumbilical head598 that is connected the umbilical600.
• The lowerwiper plug assembly602 has sealinglobe604 and this assembly is firmly attached to the body of the progressive cavity pump at the location shown inFIG. 24. Lower wiper plug assembly haslower bypass passage606 which has electrically operatedvalves608 and610. The upperwiper plug assembly612 has sealinglobe614 and this assembly is firmly attached to the sections of the apparatus having the gear box and the electrical submersible motor at the location shown inFIG. 24. The upper wiper assembly also has permanently openupper bypass port616 in the embodiment shown inFIG. 24.
• In terms ofFIG. 24, and when the electrical submersible motor is suitably turning the rotor of the progressive cavity pump (PCP), a volume of fluid ΔV2 per unit time in the wellbore is pumped into thelower side port618 of the PCP and out of theupper side port620 of the PCP. Withvalves608 and610 closed, the fluid ΔV2 is then forced through theupper bypass port616 into the portion of the well above the upper surface of the upper wiper plug assembly. In this manner, the Smart Shuttle is then forced downward into the wellbore. TheRetrieval Sub620 is attached to the body of the Smart Shuttle byquick change collar622 that in turn is connected to the lower body of the progressive cavity pump. This, and related embodiments of the Smart Shuttle is used to transport equipment attached to the Retrieval Sub into wells and out of wells. The Smart Shuttle is an example of a “well conveyance means”, or simply, a “conveyance means”. Fluid conduction means624 is able to conduct any fluids available from umbilical600 through theRetrieval Sub620, although that fluid conduction means624 is not shown inFIG. 24 for simplicity. Fluid conduction means624 is fabricated using tubing and technology currently available in the oil and gas industry.
• FIG. 25 shows another well conveyance means. Umbilical626 possesses one or more electrical conductors. In several preferred embodiments, umbilical626 possesses one or more high power electrical conductors.Umbilical head628 connects the umbilical totractor conveyor630. The tractor conveyor has at least onefriction wheel632 which engages the interior ofpipe634. The tractor conveyor has four friction wheels as shown inFIG. 25. Quickchange collar assembly635 connects the tractor conveyor to theRetrieval Sub636.
• Thetractor conveyor630 with itsRetrieval Sub636 installed inFIG. 25 is an example of a “tractor conveyance means”, a “tractor deployer”, or a “downhole tractor deployment device”. Electrical energy delivered via the umbilical to the tractor conveyor is used to drive electrical motors and/or electro-hydraulic systems637 to provide rotational energy to the friction wheels (although the details of element637 are not shown inFIG. 25 for simplicity). That rotational energy causes the tractor conveyor to move within the well.
• The tractor conveyance means inFIG. 25 provides similar operational features as different embodiments previously described heretofore as Smart Shuttles. Fluid conduction means638 is able to conduct any fluids available from umbilical626 through theRetrieval Sub636, although that fluid conduction means638 is not shown inFIG. 24 for simplicity. Fluid conduction means638 is fabricated using tubing and technology currently available in the oil and gas industry.
• By analogy with the Smart Shuttle, one embodiment of the tractor conveyance means may be used as a portion of an “automated well drilling and completion system”. As described herein, this automated system is called the “tractor conveyance system” or the “automated tractor conveyance system”. The tractor conveyance means is substantially under the control of a computer system that executes a sequence of programmed steps that has at least one computer system located on the surface of the earth and has means to convey at least one completion device attached to the Retrieval Sub into the wellbore under the automated control of the computer system. The automated system has at least one sensor means located within the tractor conveyance means, has first communications means that provides commands from the computer system to the tractor conveyance means, has second communications means that provides information from the sensor means to the computer system, where the execution of the programmed steps of the computer system to control the tractor conveyance means takes into account information received from the sensor means to optimize the steps executed by the computer system to drill and complete the well.
• The Retrieval Sub can be attached to a number of the devices shown inFIG. 26. Those devices include any commercial tool ordevice640; anylogging tool642; anytorque reaction centralizer644; anyscraper646; anyperforating tool648; anyflow meter650; any Downhole Rig withrotary bit652; any UniversalCompletion Device™654; anystraddle packer656; anyinjection tool658; any oil/gas separator660; any flowline cleaning tool662; anycasing expanding tool664; anyplug666; anyvalve668; and anylocking mechanism670. These different tools are either defined in applicant's applications or are tools used in the oil and gas industry. The point is that any of these devices can be attached to the Retrieval Sub of the CasedHole Smart Shuttle672 or to the Retrieval Sub of the OpenHole Smart Shuttle674. These devices may similarly be attached to the Retrieval Sub of the tractor conveyance means. Each such device in this paragraph may be called a “completion device” and collectively, these may be referenced as “completion devices”.
• These devices specified in the previous paragraph may be used for a variety of different purposes in the oil and gas industry. Many of those tools can be used to serve wells. Please refer toFIG. 27 that shows a diagrammatic representation of functions that may be performed with the Smart Shuttle or the Well Locomotive.FIG. 27 shows that the Smart Shuttle or the Well Locomotive shown diagrammatically aselement676 may be used for the purposes of completion678 (ie., to perform completion services on a well); production & maintenance680 (ie., to perform production and maintenance services on a well); enhanced recovery682 (ie., to perform enhanced recovery services on a well); and fordrilling684. Under completion functions, or “completion services”, the Smart Shuttle and Well Locomotive may be used for the completion of extendedreach lateral wells686; for logging and perforating688; for stimulation andfluid services690; may be used to install the UniversalCompletion Device™692; and may be used to install completion hardware such as plugs, valves, gages, etc.694. Under production and maintenance functions, or “production and maintenance services”, the Smart Shuttle and Well Locomotive may be used forflow assurance services696; for maintenance andrepair698; for workovers, that include logging, perforating, etc.,700; and for reservoir monitoring andcontrol702. Under enhanced recovery functions, or “enhanced recovery services”, the Smart Shuttle and Well Locomotive may be used for recompletions, well extensions, andlaterals704; to installdownhole separators706; to performartificial lift708; to facilitatedownhole injection710; and forfluid services712. Under drilling functions, or under “drilling services”, the Smart Shuttle and the Well Locomotive may be used forcasing drilling purposes714; for linerdrainhole drilling purposes716; forcoiled tubing drilling718; and for extendedreach lateral drilling720. Extensive details are provided in about each of these functions in the related U.S. Disclosure Documents and in the related Provisional Patent Applications cited above.
• Any one or more of the functions provided in the previous paragraph is called a “well service”. Two or more of such functions are called “well services”. The execution of the programmed steps of the automated computer system to control the Smart Shuttle®, or tractor conveyance means, takes into account information received from the sensor means within the tractor conveyance means to optimize the steps executed by the computer system to service the well.
• The above umbilicals have stated calculations pertaining to lengths of 20 miles. However, the umbilicals can be any length from 100's of feet to 20 miles. The extreme distance of 20 miles was chosen to show neutrally buoyant umbilicals can provide high power and high speed data communications at great distances that has heretofore not been recognized in the oil and gas industry.
• As stated previously, the phrase “substantially neutrally buoyant”, “essentially neutrally buoyant”, “near neutral buoyant”, and “approximately neutrally buoyant” may be used interchangeably. In several preferred embodiments of the invention, the meaning of these terms is that in the presence of the well fluids, that the buoyancy of the umbilical causes the typical friction of the umbilical against the well to be substantially reduced.
• As stated earlier, the tractorconveyor tractor conveyor630 with itsRetrieval Sub636 inFIG. 25 is an example of a “conveyance means”, a “tractor conveyance means”, a “tractor deployer”, or a “downhole tractor deployment device”. There are many “well tractors”, or devices related to well tractors, a selection of which are described in the following documents: U.S. Pat. Nos. 6,347,674; 6,345,669; 6,318,470; 6,296,066; 6,273,189; 6,257,332; 6,241,031; 6,241,028; 6,225,719; 6,179,058; 6,179,055; 6,173,787; 6,089,323; 6,082,461; 5,954,131; 5,794,703; 5,547,314; 5,375,668; 5,209,304; 5,184,676; 5,121,694; 5,018,451; 5,040,619; 4,960,173; 4,686,653; 4,643,377; 4,624,306; 4,570,709; 4,463,814; 4,243,099; 4,192,380; 4,085,808; 4,071,086; 4,031,750; 3,969,950; 3,890,905; 3,888,319; 3,827,512; in EP0564500B1; and in WO9806927; WO9521987; WO9318277; and WO9116520; entire copies of which are incorporated herein by reference. Entire copies of the 39 cited references in this paragraph are incorporated herein by reference. Many of these devices are means to cause or generate movement within wellbores. Such “movement means” may be attached to a device similar to theRetrieval Sub636. Devices similar toRetrieval Sub636 are called “retrieval means”. So, movement means may be coupled to retrieval means to make a “tractor conveyance means”, or tractor deployers, or downhole tractor deployment devices.
• In view of the above, several embodiments of this invention use a closed-loop system to service a well for producing hydrocarbons from a borehole in the earth having at least one computer system located on the surface of the earth, which possess at least one conveyance means to convey at least one completion device into the borehole under the automated control of the computer system that executes a series of programmed steps, which possess at least one sensor means located within the conveyance means, which have first communications means that provides commands from the computer system to the conveyance means and possessing second communications means that provides information from the sensor means to the computer system, whereby the execution of the programmed steps by the computer system to control the conveyance means takes into account information received from the sensor means to optimize the steps executed by the computer to service the well. Such system is called a “closed-loop tractor conveyance system”. The closed-loop system may also be used to monitor and control production of hydrocarbons from the wellbore.
• The above described umbilicals, and other variations of such umbilicals that meet the above defined operational specifications, could be manufactured on a contractual basis by a firm called ABB Offshore Systems that is located in Stavanger, Norway, that has its U.S.A. office that may be reached through ABB Offshore Systems, Inc., having the address of 8909 Jackrabbit Road, Houston, Tex. 77095, having the telephone number of (281) 855-3200, that has its website that can be reached through www.abb.com. The above described umbilicals, and other variations of such umbilicals that meet the above defined operational specifications, might be manufactured on a contractual basis by a firm called the Fiberspar Corporation that may be reached at 28 Patterson Brook Road, West Warehan, Mass. 02576, having the telephone number (508) 291-9000, which has its website at www.fiberspar.com. This firm is capable of supplying various spoolable composite tubes capable of being spooled onto a reel having relevant anisotropic characteristic, a specified burst pressure, a specified collapse pressure, a specified tensile strength, a specified compression strength, a specified load carrying capacity, which is also bendable. Some of these tubes include an inner liner material, an interface layer, fiber composite layers, a pressure barrier layer, and an outer protective layer. The fiber composite layers can have triaxial braid structure. The composites may be fabricated from carbon-based composites.
• In the above, syntactic foam materials were described in various preferred embodiments to change the apparent buoyancy of an umbilical in the presence of other surrounding fluids. However, any material of a different density may be used for this purpose.
• A preferred embodiment above has described an apparatus to drill oil and gas wells having subterranean electric drilling machine disposed in a wellbore such as that shown aselement94FIG. 6. The subterranean electric drilling machine possesses at least one downhole electric motor that is shown aselement114 inFIG. 6. This electric motor rotates a rotary drill bit identified aselements106,110 and112 inFIG. 6. This electric motor rotates the drill bit at a selected RPM determined by the frequency, current and voltage applied to input terminals of the electric motor as shown inFIG. 2 and inFIG. 3. One advantage of such an electrically operated drill bit operating at relatively high RPM is that it produces very fine rock cuttings that are easily transported to the surface by mud flow. The input terminals of the electric motor are identified as the inputs to the downholeelectrical load22 inFIG. 2, which in several embodiments is an electric motor, which are also attached to thesensing unit24. The input terminals of the electric motor are shown a the leads attached to either side ofelement34 inFIG. 2. The electric motor operates properly with a particular voltage level applied to its electrical input. Please refer to the preferred embodiment discussed in relation toelectric motor34 inFIG. 3. It is important to note that in several preferred embodiments, theelectrical motor34 inFIG. 3 is dissipating 160 horsepower (119 kilowatts). A surface power supply means located on the surface of the earth provides a voltage output that is identified withelement20 inFIG. 2. An umbilical means disposed in the wellbore surrounded by well fluids connecting the surface power supply means to the subterranean electric drilling machine provides electrical power to the electrical input of the electric motor. For example, such an umbilical means is shown aselement116 inFIG. 6 and inFIG. 9. The umbilical means possesses insulated electric wires as shown inFIGS. 1, and20. The umbilical means possess high speed data communications means such as highspeed data link14 inFIG. 1. The umbilical means possesses a fluid conduit for conveying drilling fluids through the interior of the umbilical means such aselement8 inFIGS. 1 and 506 inFIG. 20. The preferred embodiment has means to measure first voltage applied to the first electrical input of the electrical motor as shown byelement24 inFIG. 2. The preferred embodiment possesses means to transmit information related to the measured first voltage through a high speed data communications means within the umbilical to a computer located on the surface of the earth by using the highspeed data link14 inFIG. 1. The embodiment further possesses computer controlled means to adjust the first voltage output as shown byelement28 inFIG. 2. Thecomputer system26 inFIG. 2 is used to maintain first voltage input at a particular voltage level to provide proper operation of the electric motor within the subterranean electric drilling machine.
• In several preferred embodiments, theelectric motor34 inFIG. 3 dissipates in excess of 60 kilowatts. This is important because it is the recollection of the inventors that several scientists and senior managers of a major oil services company stated their opinions that it would be impossible to provide over 60 kilowatts to an electric motor, or any other electrical load, at distances of up to 20 miles from a wellsite through any type of reasonably sized umbilical that would be practical to use within wellbores. According to the recollection of the inventors, these senior managers and scientists clearly stated their opinions before the invention herein was disclosed to those particular individuals. Yet further from this recollection, it apparently never occurred to these same scientists and senior managers that any such umbilical delivering in excess of 60 kilowatts could also be neutrally buoyant. However, only after disclosure of the invention herein to those scientists and senior managers, did they apparently accept that such umbilicals could be designed and built. Accordingly, because the individuals involved are well known in the oil and gas industry, and are experts in fields directly pertaining to the invention, the preferred embodiment described herein is not obvious to one having ordinary skill in the art.
• Therefore, a preferred embodiment is an apparatus to drill oil and gas wells comprising:
• (a) a subterranean electric drilling machine disposed in a wellbore that possesses at least one electric motor that rotates a rotary drill bit at a selected RPM, whereby the electric motor possesses first electrical input, whereby the electric motor properly operates with a particular voltage level applied to first electrical input, and whereby the electric motor dissipates in excess of 60 kilowatts with the particular voltage level applied to the first electrical input;
  (b) surface power supply means located on the surface of the earth providing first voltage output;
  (c) umbilical means disposed in the wellbore surrounded by well fluids connecting the surface power supply means to the subterranean electric drilling machine that provides electrical power to the first electrical input of the electric motor, whereby the umbilical means possesses insulated electric wires, whereby the umbilical means possesses high speed data communications means, and whereby the umbilical possesses a fluid conduit for conveying drilling fluids through the interior of the umbilical means;
  (d) means to measure first voltage applied to the first electrical input of the electrical motor;
  (e) means to transmit information related to the measured first voltage through the high speed data communications means within the umbilical to a computer located on the surface of the earth;
  (f) computer controlled means to adjust the first voltage output so as to maintain first voltage input at the particular voltage level to provide proper operation of the electric motor within the subterranean electric drilling machine.
• Another preferred embodiment of the invention described in the previous paragraph provides an umbilical means that a approximately neutrally buoyant within the well fluids to reduce the frictional drag on the neutrally buoyant umbilical.
• In view of the above disclosure, yet another preferred embodiment is the method of feed-back control of an electric motor having at least one voltage input located within a subterranean electric drilling machine located in a borehole that dissipates at least 60 kilowatts that receives power from a surface power supply through an umbilical surrounded by well fluids that possesses at least two insulated electric wires, whereby the umbilical also possesses high speed data link for data communications, comprising the steps of:
• (a) measuring the voltage input to the electric motor;
  (b) sending information related to the measured voltage input through the high speed data link to a computer located on the surface of the earth; and
  (c) using the computer to adjust the voltage output of the surface power supply that is used to control the voltage input to the electrical motor.
• Another preferred embodiment of the invention described in the previous paragraph provides an umbilical that is a approximately neutrally buoyant within the well fluids to reduce the frictional drag on the umbilical.
• In view of the above disclosure, yet another preferred embodiment is the method of providing in excess of 60 kilowatts of electrical power to the electrical motor of a subterranean electric drilling machine through a substantially neutrally buoyant composite umbilical containing electrical conductors to reduce the frictional drag on the neutrally buoyant umbilical.
• In view of the disclosure related toFIGS. 22 and 23, it is evident that the invention may be used to provide electrical power to an electric motor located within a remotely operated vehicle. Accordingly, a preferred embodiment of the invention provides a method of feed-back control of an electric motor having at least one voltage input located within a remotely operated vehicle that dissipates at least 60 kilowatts that receives power from a power supply located on a ship through an umbilical surrounded by sea water that possesses at least two insulated electric wires, whereby the umbilical also possesses high speed data link for data communications, comprising the steps of:
• (a) measuring the voltage input to the electric motor;
  (b) sending information related to the measured voltage input through the high speed data link to a computer located on the ship; and
  (c) using the computer to adjust the voltage output of the power supply located on the ship that is used to control the voltage input to the electrical motor.
• Accordingly, yet another preferred embodiment of the invention is the method of providing in excess of 60 kilowatts of electrical power to the electric motor of a remotely operated vehicle through an umbilical containing electrical conductors and at least one high speed data communications means.
• Several of the above preferred embodiments describe the Subterranean Electric Drilling Machine™, or simply the Subterranean Drilling Machine™ (SDM™), that performs Subterranean Electric Drilling™ (SED™) that is used to construct a Subterranean Electric Drilled Monobore Well™ or an SED Monobore Well™. Several of the above preferred embodiments also describe the Subterranean Liner Expansion Tool™ (SLE™) otherwise called the Casing Expansion Tool™(CET™).
• FIG. 28 shows a fixedplatform800 penetratingocean water804 that is anchored in the ocean bottom at aparticular location808.Production flowline812 andproduction flowline816 carry oil and gas production to the fixed platform. Steel cased well820 penetrates the ocean bottom atlocation824 which is terminated in the firstsubsea Xmas Tree828. Oil and gas production flows from the first Xmas Tree throughjumper832 tomanifold836. Oil and gas production flows frommanifold836 throughflowlines812 and816 to theTLP800. Subsea control umbilical840 is connected to mid-flowline tie-inmanifold844 for a second Xmas Tree that in turn is connected to subsea control umbilical848 that proceeds to the Umbilical Termination Assembly (“UTA”)852. (The second Xmas Tree is not shown inFIG. 28 for the purposes of simplicity.) Control signals are then sent through the Flying Leads, such asFlying Lead856, that in turn are connected to the first Xmas Tree to control well production. Mid-flowline tie-inmanifold844 is connected tojumper860 that is connected toassembly864. Oil and gas production also flows throughflowline868 toassembly864 and throughflowline872 to the TLP.
• Installations such as shown inFIG. 28 are typical in the Gulf of Mexico.FIG. 28 shows a typical satellite field system. In some cases, the flowlines are single steel pipes, which are subject to wax build-up and to other blockage problems such as hydrates, scales or other solids forming from the production due to a loss in static pressure or in temperature, or to any other process or mechanism. In other cases, steel pipe-in-pipe systems with the outer pipe being externally insulated and hot water circulated through the annulus between the two pipes is used to heat the flowlines to avoid wax build-up and other blockage problems.
• InFIG. 28, the “host” is illustrated as a fixed platform. However, many other “hosts” are possible including the following: an FPSO (a “Floating, Processing, Storage and Offloading” facility); all types floating platforms; Tension Leg Platforms (“TLP's); SPARS; floating platforms with dry tree risers including TLP's and SPARS; etc. Here a SPAR is a floating moored structure for offshore drilling and/or production operations, which is typically a deep draft structure with very low motions due to the environment, and is especially suited for deepwater, and often supports dry surface trees. For the purposes of this invention, a “host” may include any of the previously listed structures associated with the formal definition of an “offshore platform” as defined above in quotes.
• FIG. 29 shows another “host” system.FIG. 29 shows Floating Production, Storage, and Offloading structure (FPSO)876 loading crude throughflexible line880 toshuttle tanker884 located onocean surface888. This is a typical FPSO arrangement as used in offshore Brazil and West Africa.Mooring component892 is anchored to the sea bottom atlocation896.Mooring component900 is anchored to sea bottom atlocation904.Subsea wellhead908 atlocation912 on the sea bottom passes crude production throughflowline916 to the FPSO.Subsea wellhead920 atlocation924 on the sea bottom passes crude production throughflowline928 to the FPSO.Subsea wellhead932 atlocation936 on the sea bottom passes crude production throughflowline940 to the FPSO.Subsea wellhead944 atlocation948 on the sea bottom passes crude production throughflowline952 to the FPSO. Often, the flowlines are single pipes that are subject to blockage from wax and other substances.
• Another host is shown inFIG. 30. Here floatingplatform956 is shown floating inocean960 havingocean surface964. Steel cased well968 penetrates thesea bottom972 atlocation974, and is attached towellhead976.Steel flowline980 is attached towellhead976 and lies onsea bottom972 for a distance until it raises off the sea bottom atposition984. The upper extremity of theflowline988, also known as a riser, is connected to the floating platform, and the riser is suspended below the floating platform having a minimum radius of curvature R atlocation992 shown inFIG. 30.
• The Electric Flowline Immersion Heater Assembly (“EFIHA”) is generally shown aselement996 inFIG. 30. The EFIHA shown inFIG. 30 possesses Electrically Heated Composite Umbilical (“EHCU”)1000. The inside diameter of thesteel flowline980 is shown by the legend ID(FL) inFIG. 30. The wall thickness of thesteel flowline980 is WT(FL), which is not shown inFIG. 30 in the interests of brevity. The outside diameter of the EHCU is shown by the legend OD(IH) inFIG. 30. The wall thickness of the EHCU is WT(IH), which is not shown inFIG. 30 in the interests of brevity.Hydraulic seal1004 is attached to the outside diameter of the EFIHA atlocation1008.Hydraulic seal1004 may be comprised of multiple individual hydraulic sealing elements1012,1016,1020, and1024, which four elements are shown inFIG. 30, but which are not so labeled in the interests of simplicity.
• Hydraulic pressure may be generated with hydraulic equipment1030 (not shown in the interests of simplicity inFIG. 30) located on the floatingplatform956. This hydraulic pressure may be applied to the annular space defined by the difference between the inside diameter of the flowline ID(FL) and the outside demeter of the EHCU that is OD(IH) that is shown asregion1034 inFIG. 30. The hydraulic pressure applied inregion1034 inFIG. 30 is defined as P(EFIHA). This pressure acts on thehydraulic seal1004 that generates force F(EFIHA) which is applied to the EFIHA that is provided by the following equation:
• 
  F(EFIHA)=π{[ID(FL)/2]²−[OD(IH)/2]²}{P(EFIHA)}  Equation 2.
• The force shown inEquation 2 is used to force the EFIHA down into the steel flowline. In one preferred embodiment of the invention, ifwellhead976 is set by control means1038 so that no fluid may flow back into the well, then when the EFIHA is forced downward into the well by hydraulic force F(EFIHA), any displaced fluid in the sealed system flows up the inside of the EFIHA throughregion1042 within the EFIHA and to the floating platform atlocation1046. This is called “backflow” within the EFIHA. So, in this case, the displaced fluid flows up the interior of the F(EFIHA) to the floating platform.
• The EFIHA also possesses additional centralizing andhydraulic sealing elements1048 and1052. Instrumentation assembly andcontrol assembly1056 provides measurements of the ambient well conditions such as the pressure P(EFIHA), temperature (EFIHA), the depth, etc. The force used to drive the EFIHA into the well results in a downward velocity V(EFIHA) that may be a function of time. This downward velocity V(EFIHA) influences the pressure P(EFIHA). The force F(EFIHA) is adjusted so that the pressure P(EFIHA) does not exceed some predetermined maximum pressure P(EFIHA-MAX). The Electrically Heated Composite Umbilical (“EHCU”)1000 possesses internal electric heater wires, wires to power the instrumentation andcontrol assembly1056, means for high speed bidirectional communications, and power wires for any other services or purposes. As one example,wires494 and496 in the umbilical shown inFIG. 20 may be used instead as electrical resistors to generate heat to heat the EHCU. In this case, the heat delivered to the EHCU is equal to the following:
• 
  H(EHCU)=[I(EHCU)]²R(EHCU)  Equation 3.
• Here, H(EHCU) is the power in watts (“heat”) delivered to the EHCU, the symbol I is the time averaged electrical current flowing throughwires494 and496 inFIG. 20, and R(EHCU) is the combined series resistance ofwires494 and496. The current I is caused to flow through the resistors by a power supply that is not shown for simplicity.
• Instrumentation andcontrol assembly1056 may be used to sense the depth of the EHCU and the distance between the end of the EHCU and the wellhead shown by the legend Z(IH). In one preferred embodiment of the invention, when Z(IH) reaches a predetermined value, then at least one hydraulic locking mechanism (not shown inFIG. 30 for simplicity) within instrumentation andcontrol assembly1056 may be used to lock the EHCU into place within the well.
• In one preferred embodiment of the invention, when it is time to retrieve the EHCU, and withwellhead976 is set by control means1038 so that no fluids may flow into the wellhead, then pressuring up the interior ofregion1042 will apply pressure to the downhole side ofseal1004 and force the EHCU towards the floatingplatform956 and out of the well. Suitable spooling and handling equipment for the EHCU are provided on the floatingplatform988 which are not shown inFIG. 30 in the interests of simplicity. In another preferred embodiment, the EHCU is simply pulled out of the well by the spooling and handling equipment.
• In another preferred embodiment, and after the EFIHA is locked in place within the well, a cross-over valve1055 (not shown inFIG. 30 for simplicity) can be located atlocation1058 which location is towards the floating platform from the position ofseal1004. When production is allowed to flow to the floating platform, this cross-over valve can be set to any one of three states (“State1”, “State2”, and “State3”). In State1, oil and gas production would proceed through the interior of EHCU to the floating platform. For example, in State1, oil and gas production would flow throughregion1057 of the EHCU that is located towards the floating platform fromseal1004. InState2, oil and gas production would flow throughregion1058 located between the outside diameter of the EHCU and the inside diameter of the flowline.State2 has the advantage that all the heat generated in the EHCU is transferred to the surrounding production. InState3, the oil and gas production would flow through bothregions1057 and1058 simultaneously. There are many variations of the invention.
• The next 12 paragraphs are paraphrased frompage 66, line 41, topage 68,line 38, of Ser. No. 09/487,197, now U.S. Pat. No. 6,397,946 B1, that issued on Jun. 4, 2003, having the inventor of William Banning Vail III, that was incorporated entirely by reference in co-pending Ser. No. 10/223,025, having the Filing Date of Aug. 15, 2002, that is entitled “High Power Umbilicals for Subterranean Electric Drilling Machines and Remotely Operated Vehicles”. These 12 paraphrased paragraphs originally related to FIG. 23 in U.S. Pat. No. 6,397,946, but now relate toFIG. 31 herein. In FIG. 23 in U.S. Pat. No. 6,397,946 B1, a coiled tubing was conveyed downhole. InFIG. 31 herein, an Electric Flowline Immersion Heater Assembly (“EFIHA”) having an electrically heated composite umbilical (“EHCU”) is conveyed into a flowline. In addition, an extra “0” was added to all numerals that appeared in the corresponding text of U.S. Pat. No. 6,397,946 B1, so for example element780 in FIG. 23 in U.S. Pat. No. 6,397,946 is now labeled aselement7800 inFIG. 31 herein.
• However, the Smart Shuttles may be conveyed downhole with an attached Electric Flowline Immersion Heater Assembly (“EFIHA”) having an electrically heated composite umbilical (“EHCU”) that is conveyed into a flowline. Such a Smart Shuttle with Retrieval Sub that is conveyed downhole that is attached to an EHCU is shown inFIG. 31 herein. In several preferred embodiments of the invention, the EHCU conveyed by the Smart Shuttle into the flowline as shown inFIG. 31 may be forced into the flowline by three different mechanisms: (a) by using mechanical “injectors” at the surface to force the coiled tubing downward into the flowline; (b) the PCP/ESM assembly may be used to assist by “pulling” the Smart Shuttle into the flowline; and (c) yet further, hydraulic forces on fluids from the surface may also force the Smart Shuttle into the flowline. That these three independent methods may be used to force the Smart Shuttle with its attached Retrieval Sub downward into the flowline will become better apparent with the following description of the elements inFIG. 31.
• Most of the elements inFIG. 31 throughelement7200 have been previously described in relation to FIG. 23 in U.S. Pat. No. 6,397,946 B1. The Progressive Cavity Pump is labeled withelement6800. The Progressive Cavity Pump is coupled togear box6830 that is in turn coupled to theElectrically Submersible Motor6840, which in turn is connected toelectronics assembly6850 having any downhole computer, sensors, and communications system, which in turn is connected to thequick change collar7700. The assembly below the quick change collar inFIG. 31 is often referred to as the Progressive Cavity Pump/Electrical Submersible Motor assembly that is abbreviated as the “PCP/ESM assembly”. Therefore, the “PCP/ESM assembly” is attached to thequick change collar7700 inFIG. 31.
• InFIG. 31, an Electric Flowline Immersion Heater Assembly (“EFIHAI”) that is generally shown as numeral7722 has an Electrically Heated Composite Umbilical (“EHCU”)7724 that is conveyed intosteel flowline6782.Tubing Termination Assembly7780 hasthreads7800 that mate to the threadedend7762 ofEHCU7724. So, the Tubing Termination Assembly is inserted into the flowline and is attached to the threadedend7762 of theEHCU7724. In one preferred embodiment, any fluids that flow into, or out of, the EHCU are conducted to, and from, the interior of the flowline throughfluid channel7820.Valve7832 located withinfluid channel7820 can be used to cut off any fluid flow through the channel.Valve7832 may be open or closed as desired. For many of the following preferred embodiments, it is assumed that thisvalve7832 is open unless explicitly stated otherwise. Thewireline7742 is connected totop submersible plug7840 that connects tolower submersible plug7860 which in turn passes the electrical conductors from the wireline to the quick change collar. The bundle of electrical conductors passing to the quick changer collar is designated with the numeral7880 inFIG. 31. Within the quick change collar is yet another electrical plug assembly that provides power and electrical signals through a bundle of wires to the “PCP/ESM assembly” that is not shown inFIG. 31 solely for the purposes of simplicity. Typical design and assembly procedures used in the industry are assumed throughout this specification. It is often the case that a quick change collar surrounds male and female mating electrical connectors, which is typically the case in “logging tools” used in the wireline logging industry. Those connectors mate at the location specified by the dashedline7890 shown on the interior of the quick change collar inFIG. 31.
• In addition, theTubing Termination Assembly7780 also possessesexpandable packer7900. Upon command from the surface, this expandable packer can be inflated within the flowline to seal against the flowline as may be required during typical well completion procedures, and typical workover procedures, that are used in the industry. This expandable packer can also be used for a second purpose of forcing the Smart Shuttle into the wellbore as described below. This packer can also be used for additional purposes as described below.
• With reference toFIG. 31, the Smart Shuttle may be forced downhole by three mechanisms that are described in separate paragraphs as follows.
• In a first preferred embodiment of the invention, mechanical “injectors” at the surface are used to force the Electric Flowline Immersion Heater Assembly (“EFIHA”)7722 and its electrically heated composite umbilical (“EHCU”)7724 into theflowline6782. These mechanical “injectors” were previously described in U.S. Pat. No. 6,397,946 B1, an entire copy of which is incorporated herein by reference.
• In a second preferred embodiment of the invention, the electrically energized Progressive Cavity Pump forces fluid ΔV2 into thelower side port7120 of the PCP and out of theupper side port7140 of the PCP, and the Smart Shuttle is conveyed downhole. If this method is used by itself, and ifexpandable packer7900 is in its deflated state as shown by the solid line inFIG. 31, then no fluid would necessarily flow to the surface throughfluid channel7820. It could, but it is not necessary in this embodiment, and under the circumstances described.
• In a third preferred embodiment of the invention, and in analogy with the pump-down singlezone packer apparatus658 described in FIG. 17 in U.S. Pat. No. 6,397,946 B1, theexpandable packer7900 inFIG. 31 is inflated so as to make a reasonable seal against theflowline6782, but not so firmly so as to lock the device in place. InFIG. 31, the solid line labeled with numeral7900 shows the uninflated state of the expandable packer, and the dotted line shows the expanded, or inflated, state ofexpandable packer7900. Then, in analogy with fluid flow described in FIG. 17 of U.S. Pat. No. 6,387,946 B1, fluid forced into the upper flowline inannular region7726 will force the apparatus attached to the expandable packer downward into the wellbore, and any fluid ΔV3 displaced is forced upward throughfluid channel7820 and into the interior of theEHCU7728 which in turn flows to the surface in analogy with previous description of fluid flow through coiled tubing to the surface in relation to FIG. 17 in U.S. Pat. No. 6,397,946. This of course assumes thatvalve7832 is open.
• In principle, all first, second, and third methods of conveyance downhole can be used simultaneously, provided thatvalves6980 and7000 are set in their appropriate positions for the applications, provided thatvalve7832 is set in its appropriate position, and provided theProgressive Cavity Pump6800 is suitably energized.
• For simplicity, the particular embodiment of the invention shown inFIG. 31 will be called in certain portions of the text that follows the “Electric Flowline Immersion Heater Assembly with Wireline Smart Shuttle” abbreviated “EFIHAWWSS” that is generally designated as numeral7922 inFIG. 31.
• Any smart completion device may be attached to theRetrieval Sub7180 during any such conveyance downhole. For example, a casing saw or another packer can be installed on the Retrieval Sub so that many different services can be performed during one trip downhole. The casing saw and packers are descried in U.S. Pat. No. 6,397,946 B1. These include perforating, squeeze cementing, etc.—in fact many of the methods to complete oil and gas wells defined in the book entitled “Well Completion Methods”, “Well Servicing and Workover”,Lesson 4, from the series entitled “Lessons in Well Servicing and Workover”, Petroleum Extension Service, The University of Texas at Austin, Austin, Tex., 1971, an entire copy of which is incorporated herein by reference.
• In another preferred embodiment of the invention, the apparatus inFIG. 31 may be used to test production, or to assist production if it is used in another manner. In this embodiment, an electrically actuated production flowline lock7940 (not shown inFIG. 31) is attached to theRetrieval Sub7180. It has passages through it so that hydrocarbons below it can pass through it if necessary, but it otherwise locks the apparatus inFIG. 31 to the inside of the casing. Once locked in place, the PCP/ESM assembly can pump hydrocarbons throughlower side port7120 of the PCP and out of theupper side port7140 of the PCP. Thereafter, hydrocarbons are pumped throughfluid channel7820 of theTubing Termination Assembly7780 inFIG. 31 provided that theexpandable packer7900 is suitably inflated. There are many variations on this particular embodiment of the invention but they are not further described here solely in the interests of brevity. With this embodiment, and with the PCP forcing fluids up the inside of the EHCU, then this provides a method of artificial lift for the produced hydrocarbons.
• FIG. 31 also shows the Retrieval Subelectrical connector3130, therotor6810 of the Progressing Cavity Pump, and thestator6820 of the Progressing Cavity Pump. TheRetrieval Sub7180 is attached to the body of the Smart Shuttle byquick change collar7200 that in turn is connected to the lower body of the Progressive Cavity Pump. The lowerwiper plug assembly6920 has sealinglobe6940 and this assembly is firmly attached to the body of the Progressive Cavity Pump at the location generally specified by numeral6960 and this assembly further haslower bypass passage6980 which has electrically operatedvalves7000 and7020. InFIG. 31, the Smart Shuttle is comprised of the ProgressingCavity Pump6800 and thewiper plug assembly6920.
• FIG. 31 may be used to illustrated yet other preferred embodiments of the invention. The region of the well below the lowerwiper plug assembly6920 is designated byelement6802. The annular region of the well between the lowerwiper plug assembly6920 and theinflatable packer7900 is designated byelement6804. The annular region of the well above the inflatable packer has already been designated by numeral7726. In another preferred embodiment of the invention, the PCP may be used to pump fluids fromregion6802 toregion6804. In this embodiment,valve7832 is closed and theinflatable packer7900 is in its uninflated state that is shown by the solid line inFIG. 31. In this embodiment, hydrocarbons produced from the well will be pumped to the surface throughregion7726 of the well. In this case, the EHCU will heat the hydrocarbons to prevent any build up of wax, hydrates, or other blockage substances in the well. In yet another preferred embodiment of the invention, valve7830 may also be left open, and in such case produced hydrocarbons would not only flow throughregion7726 to the surface but also within theEHCU7728 to the surface.
• InFIG. 32, all the elements have been described exceptelements7723,7725,7764,7842,7862,7924,8000, and8010. InFIG. 32, there is no wireline within the Electrically Heated Composite Umbilical (“EHCU”)7725. InFIG. 32, an Electric Flowline Immersion Heater Assembly (“EFIHA”) is generally shown as numeral7723 having an Electrically Heated Composite Umbilical (“EHCU”)7725 that is conveyed intosteel flowline6782.Tubing Termination Assembly7780 hasthreads7800 that mate to the threadedend7764 ofEHCU7725.Element7924 inFIG. 32 generally designates the Smart Shuttle Conveyed Electric Flowline Immersion Heater Assembly (“SSCEFIHA”) disposed within theflowline6782.
• TheEHCU7725 possesses electrical heater wires, power cables, any hydraulic tubes, fiber-optic cables, etc. within the wall thickness of the EHCU. The wall thickness of the EHCU is defined by the legend “WT(EHCU)”, although that legend is not shown inFIG. 32 for the purposes of simplicity.Assembly8000 provides means to pass the heater wires, power cables, any hydraulic cables, fiber-optic cables, etc. from within the wall thickness of the EHCU tojumper8010 that connects toconnector7842 that in turn mates toconnector7862.
• InFIG. 32, the Smart Shuttle is comprised of the ProgressingCavity Pump6800 and thewiper plug assembly6920. In one mode of operation of a preferred embodiment, fluid is pumped from the bottom side of the wiper plug assembly to the top side of the wiper plug assembly, and withexpandable packer7900 in the collapsed position shown inFIG. 32, the Smart Shuttle will convey the Electric Flowline Immersion Heater Assembly (“EFIHA”)7723 down into flowline6782 (providedvalve7832 is open, andvalves6980 and7000 are closed).
• FIG. 33 is similar toFIG. 32, except here,expandable packer7900, is in its extended position and makes contact with the interior wall of the flowline that is shown by the expanded solid line that is shaded. In this case, fluid pressure P provided toannular region7726 by pumps located on the host (such as a floating platform), provide a net downward force on the assembly shown inFIG. 33. There are several different modes of operation that amount to different preferred embodiments of the invention.
• In a first preferred embodiment, the Progressive Cavity Pump is turned on,valves6980 and7000 are closed, andvalve7832 is open. Here, the volume pumped by the Progressive Cavity Pump is ΔV2 is equal to ΔV3. Further, the volume pumped ΔV3 is equal to the fluid displaced in the flowline during the downward travel of the apparatus shown inFIG. 33. Therefore, if any potion of the flowline is open to a reservoirs, or other source of fluid, below the apparatus shown inFIG. 33 (in region6802), no fluid will be forced into those reservoirs, or other sources of fluid due to the downward motion of that apparatus. In another embodiment of the invention, the volume pumped by the Progressive Cavity Pump ΔV2 is always equal to, or greater than ΔV3. In yet another embodiment of the invention, the volume pumped by the Progressive Cavity Pump is ΔV2 is substantially equal to ΔV3. Many other variants of this preferred embodiment are possible. This particular method of conveyance of coiled tubings into cased wellbores was substantially described on page 67, lines 53-67, and onpage 68, lines 1-4, of U.S. Pat. No. 6,387,946 B1.
• In a second preferred embodiment, the Progressive Cavity Pump is turned off,valves6980,7000, and7832 are open, and the pressure P forces Electric Flowline Immersion Heater Assembly (“EFIHA”)7723 down intoflowline6782.
• FIG. 34 shows yet another preferred embodiment of the invention that shows an Electric Flowline Immersion Heater Assembly (“EFIHA”)7727 generally disposed in aflowline6782.Element6806 shows the annular portion of the wellbore below the EFIHA,element6808 shows the annular region of the well above theRetrieval Sub7180 and below theinflatable packer7900, and the region of the well above theinflatable packer7726 has been previously defined. The other numerals have already been defined inFIG. 34. Functionally, this is very similar to the “second preferred embodiment” described in the previous paragraph. The Smart Shuttle inFIG. 33 has been removed to make the apparatus inFIG. 34. In this embodiment,valve7832 is open, and the pressure P forces Electric Flowing Immersion Heater Assembly (“EFIHA”)7727 into the flowline. This installs the Electrically Heated Composite Umbilical (“EHCU”)7725 withinflowline6782.
• FIG. 35 shows cased well1060 penetrating thesea bottom1064 atlocation1068. Steel cased well1060 is attached toXMas Tree1072 having control means1076. TheXMas Tree1072 is attached tosteel flowline1080 that lies on the sea bottom untillocation1084. Atlocation1084 the flowline begins its ascent to the upper portion of theflowline1088, also known as a riser, that is connected to floatingplatform1092.
• For the purposes of this invention, the term “Xmas Tree”, “subsea wellhead”, and “wellhead” may be used interchangeably.
• FIG. 35 shows an Electrically Heated Composite Umbilical (“EHCU”)1096 being installed within theflowline1080 by tractor means1100 havingretractable traction wheels1104 and1108,tractor body1112,tractor locking mechanisms1116 and1120,cablehead1124 obtaining electrical power and control signals from wireline1128 (which may also be an umbilical). The cablehead provides electrical power and control signals to the tractor body throughconnector1132 which in turn provides electrical power and control signals to run the electrical motors that energize the traction wheels. The floating platform floats inocean1136 havingocean surface1140.
• InFIG. 35, the EHCU is locked to the tractor means by the tractor locking mechanisms. The traction wheels of the tractor means drags the EHCU into the flowline. After the EHCU reaches a particular distance Z35 away from the XMas Tree, then the traction wheels are turned off. The legend Z35 is defined inFIG. 35. Thereafter, the tractor locking mechanisms are released, and the traction wheels of the tractor means are retracted into the body of the tractor. The tractor means is then pulled out of the well by pulling on thewireline1128. The EHCU is left installed in place within the flowline. Not shown inFIG. 35 are locking mechanisms1122 and1123 on the EHCU which will lock it in place within the flowline during production operations. In one preferred embodiment, produced oil and gas flows through the interior of theEHCU1141 to the surface. In another preferred embodiment, produced oil and gas flows through the region between the inside diameter of the flowline and the outside diameter of the EHCU that isregion1142 inFIG. 35. In yet another embodiment, the production can flow through bothregions1141 and1142.
• InFIG. 36, steel cased well1144 is located within ageological formation1148 that penetrates thesea bottom1152 atlocation1156. Steel cased well terminates inXMas Tree1160 having control means1164.Steel flowline1168 is attached to the XMas Tree and rests on the bottom of the sea untillocation1172 at which point it raises towards the upper end of the flowline, which isriser1174, that is connected to Floating Production, Storage and Offloading (FPSO)ship1176.
• The Pump-Down Conveyed Flowline Immersion Heater Assembly (“PDCFIHA”) is generally shown aselement1180 inFIG. 36. A portion of this apparatus includes an Electrically Heated Composite Umbilical (“EHCU”)1184. Hydraulic pressure P in the annular space between the inside diameter of the flowline and the outside diameter of the EHCU, which space is designated by numeral1188 inFIG. 36, applies a force F to thehydraulic seals1192 attached to the PDCFIHA. Three seals are shown inFIG. 36 which are collectively labeled aselement1192 inFIG. 36. The hydraulic pressure P is used to carry the PDCFIHA into place a distance Z36 away from the XMas Tree. The legend Z36 is defined inFIG. 36.
• If the control means1164 has closed a valve connecting the flowline to the XMas Tree, then the displaced fluid fromannular region1196 must go somewhere. A downhole pump motor assembly is generally shown aselement1200 inFIG. 36 which is very similar to that shown inFIG. 8 herein. So, the detailed elements of the downhole pump motor assembly will not be labeled in the interests of simplicity. However, this downhole pump motor assembly possesseshydraulic pump1204 that energized byelectrical motors1208 and1212. Crude production flows intoorifice1214 of the hydraulic pump, and exits from the orifices collectively identified with numeral1216 inFIG. 36. This exiting fluid is trapped withinpump shroud1220 that is attached to the EHCU atlocation1224. Electrical power and control signals are provided by internal conductors and/or fiber optic cables within the walls of the EHCU, are broken out of the wall of the EHCU byapparatus1228 that provides power and control signals to the downhole pump motor assembly byjumper1232. The fluid then flows through the pump shroud and then through the EHCU towards the upper portion of theEHCU1236 that is connected to the FPSO ship. If the volume produced by the hydraulic pump “V35P” exceeds the volume “V35D” displaced by the downward movement of the PDCFIHA, then the PDCFIHA can proceed into the well.
• Even if the control means1164 allowed the valve from the flowline to the cased well to remain open (said valve is not shown inFIG. 36 for simplicity), as long as V35P exceeds the volume V25D, then no fluid will flow back into the steel cased well. FPSO ship is located inocean1240 havingocean surface1244.
• FIG. 37 is very similar toFIG. 36, except here the host is floatingplatform1248. All the other numerals inFIG. 37 have already been otherwise identified and described inFIG. 36.
• InFIG. 37A, all the numerals have been defined except those described in the following within this paragraph.Locks1221 and1222 serve to lock the “PDCFIHA” into place after it has been pumped down into the well. In one preferred embodiment,cross-over valve1249 allows fluid flowing inregion1250 between the downholepump motor assembly1200 and thepump shroud1220 to be directed intoannular region1188. Then production would flow throughannular region1188 to the surface. In yet another embodiment of the invention, thecross-over valve1249 would allow fluid to not only flow throughannular region1128 to the surface but fluid would also be allowed to flow in the inside of theEHCU1251 in that portion of the EHCU that is between the floating platform andcross-over valve1249. In yet another embodiment, thecross-over valve1249 may be chosen to direct production toregion1251 only; toregion1184 only; and toregions1251 and1184 simultaneously. After thelocks1221 and1222 are deployed, thehydraulic pump1204 may be used to assist well production by providing artificial lift.
• InFIG. 38, all the elements having numerals less than280 have been described in relation toFIG. 9 herein. However, casing274 inFIG. 38 may also include other forms of tubulars, including tubing.Open hole completion1252 in a reservoir withheavy oil1256 causesheavy oil1260 to flow through expandedscreen1262 into theopen hole1264. Heavy oil flows into theinflow assembly1268,thorough intake orifice1272, intohydraulic pump1276, and out exhaust orifices that are collectively labeled with1280 inFIG. 38.Electric motors1284 and1288 provide the power to drive the hydraulic pump. After the heavy oil emerges from the exhaust orifices, it is trapped byshroud1292 that is connected to Electrically Heated Composite Umbilical (“EHCU”)1296. The annular region inside the shroud open to fluid flow is defined by numeral1294. The heated production proceeds through the inside ofEHCU1298 towards the top of theEHCU1300 attached toplatform258. Electrical power and control signals are provided to the electric motors by electrical conductors and by fiber optic fibers within the wall thickness of the EHCU. The hydraulic pump provides artificial lift to the heavy oil produced.
• The Electric Flowline Immersion Heater Assembly (“EFIHA”) is generally designated withelement1304 inFIG. 38 which includes the Electrical Heated Composite Umbilical1296. In this case, hydraulic pressure P applied at the platform in the annular region between the outside diameter of the EHCU and the inside diameter of thecasing274, which isregion1308, provides a force onseals1312 that forces the EFIHA down into the well.Guides1316 help centralize the EFIHA. As the EFIHA is forced downhole, a certain displaced fluid volume V38D could be forced back into formation which could damage the formation. However, if the hydraulic pump forces a volume V38P into the EHCU, then provided that V38P is greater than V38D at all times, then no fluid is forced back into the open hole. This is important to prevent formation damage from “back flow”.
• In one of the preferred embodiments above, fluid flow from theopen hole1264 is caused to flow throughregion1294 and then through the interior of the EHCU1290 to the surface. As described above, a cross-over valve can be installed that will allow production to flow instead throughregion1308 to the surface. And yet another embodiment would allow production to flow through bothregions1298 and1308 to the surface.
• The EHCU provides heat to reduce the viscosity of the heavy oil produced from the open hole. Therefore, the artificial lift provided by the hydraulic pump is used efficiently to produce heavy oil.
• FIG. 39 shows an exploratory will with large volume fluid sampling capability.FIG. 39 shows a floatingplatform1320 with a small separator withfluid storage1324 inocean1328 havingocean surface1330. Marine blowout preventer (“BOP”)1332 is shown onocean bottom1336 atlocation1340.Borehole1344 penetrates a firstgeological formation1348, a secondgeological formation1352, and a thirdgeological formation1356 inearth1360.Casing1364 penetrates the BOP and lines the borehole down tolocation1368.Perforations1370 were made into producing intervals in the firstgeological formation1348. Downhole sampling unit shown aselement1372 inFIG. 39 possesses an open hole packer, with a sand screen filter, and a pump. The pump is used to pump samples up insulated and heatedcoiled tubing1376 through the casing to the small separator withfluid storage1324 on the floating platform.Perforations1380 were made into intervals to be tested in secondgeological formation1352. In a preferred embodiment, electrical power to operate the pump is obtained from electrical wires that are in the wall thickness of an umbilical as described earlier. On another preferred embodiment the heated tubing is comprised of an Electrical Heated Composite Umbilical (EHCU) as previously described above.
• In relation toFIG. 39, heated coiled tubing that is pumped will allow large reservoir fluid samples to be collected without the expense of a downhole completion. In an emergency, the coiled tubing is cut at the marine BOP and the downhole pump shuts in the coiled tube to prevent a blowout path. Applications include areas with soft sandstone and areas where larger fluid volumes are required to determine the reservoir production fluid properties.
• FIG. 40 shows an apparatus that provides power to upstream functions. In preferred embodiments, this would apply to subsea systems that are external to a flowline. InFIG. 40,flowline1384 is in the vicinity of asubsea installation1388 that requires electrical power. Composite umbilical1392 is attached tofirst assembly1396. Composite umbilical1392 possesses electrical wires within its wall thickness that are broken out byassembly1400 that is connected tojumper1404. The electrical power is used to energizeelectric motor1408 that is used to energize ProgressingCavity Pump1412. As has been described in relation to other embodiments above, pressure provided by an external source in the annular region between the outside diameter of the composite umbilical and the inside diameter of the flowline acting onhydraulic seal1416 forces the entire apparatus collectively called the “Connector Apparatus”1420 into the flowline. The annular region between the outside diameter of the composite umbilical and the inside diameter of the flowline is defined aselement1386 inFIG. 40. As previously described, the Progressing Cavity Pump, in conjunction withseals1424, is used to pump displaced fluid throughchannel1428 into the interior of the composite umbilical1432 for return to the surface. Landing and locatingshoulder1436 is used to provide electrical power to theflowline penetrating connector1440.Subsea power cable1444 is attached to theflowline penetrating connector1440. Theflowline penetrating connector1440 is placed into itsproper position1448 by an ROV. In various different embodiments, the flowline is penetrated for electrical, chemical and hydraulic power. This approach minimizes umbilical costs to small installations.
• FIG. 41, all the elements throughelement506 have been defined previously. In addition, two of the electrically insulatedwires1452 and1456 are used to uniformly electrically heat composite umbilical1460 inFIG. 41.
• FIG. 42 shows one embodiment of a first resistor network used to electrically heat composite umbilicals. Here,wires1452 and1456 have uniform resistance per unit length. The total resistance of each one of these electrically insulated wires is R(42) in ohms. These wires are connected together at the lower end of the composite umbilical shown byelectrical jumper1464. The total length of each wire in the composite umbilical is L(42), a legend that is defined onFIG. 42. The legend V(42) inFIG. 42 shows the voltage V(42) applied uphole to the resistive network. This first resistive network will result in uniform heating of the electrically heated composite umbilical.
• InFIG. 43, all the elements throughelements506 have been define previously. In addition, two of the electrically insulatedwires1468 and1472 are used to nonuniformly heat composite umbilical1476.
• FIG. 44 shows an embodiment of a second resistor network used to nonuniformly electrically heat composite umbilicals. Here,wire1468 does not have a uniform resistance per unit length. InFIG. 44,wire1472 has uniform resistance per unit length (but in other embodiments, this need not be the case).Wires1468 and1472 are connected together at the lower end of the composite umbilical by a shortelectrical jumper1480 having negligible electrical resistance. The length of the electrically heated composite umbilical is L(44) and that legend is defined inFIG. 44.Wire1472 has a uniform resistance per unit length, and has a total resistance in ohms of R(44D), a legend that is defined inFIG. 44.Wire1468 has a resistance in ohms of R(44A) during a first length L(44)/3; has a resistance in ohms of R(44B) during a second length L(44)/3; and has a resistance in ohms of R(44C) during a third length of L(44)/3. The legends R(44A), R(44B), and R(44C) are defined inFIG. 44. Many ways may be used to fabricatewire1468, including suitably joining together different sections of different wires having different resistances per unit length, but otherwise having the same outside diameters of insulation. The legend V(44) inFIG. 44 shows the voltage V(44) applied uphole to the resistor network. The total resistive load is the sum of R(44A), R(44B), R(44C), and R(44D). If R(44C) is greater than R(44B); and if R(44B) is greater than R(44A); and if R(44A) is greater than R(44D); then the electrically heated composite umbilical will preferentially apply more electrical heat to the lower (right-had side) of the umbilical inFIG. 44. This nonuniform electrical heating has many advantages including the application of heat in poorly insulated areas of an umbilical or coiled tubing; the matching of required heat to the transportation process of hydrocarbons within the umbilical or coiled tubing to avoid the build up of waxes and hydrates such as the preferential heating of areas where high J-T cooling may exist; etc.
• FIG. 45 shows another preferred embodiment of the electrically heated umbilical that is labeled with numeral1484 that is an armored electric cable umbilical. Steel orsynthetic armor1488 surroundsfiller1492 that encapsulateselectrical wires1496 surrounded byelectrical insulation1500. This preferred embodiment can include certain types of logging cables. The wires may be individual wires, pairs, bundles, etc. The cable may have some wires dedicated to communication, some for power and fiber optic fibers (not shown inFIG. 45) for communication and sensor service. For heating the production (besides loses due to routine power transmission losses) circuits may be dedicated to heating applications as described earlier. Sections of the circuits may be designed for heating, thus the heat can be directed to specific locations along the umbilical length as described in other embodiments above.
• FIG. 46 shows another preferred embodiment of the electrically heated umbilical generally designated aselement1504. The umbilical is surrounded by steel coiledtubing1508 having any desirable outside diameter and having any desirable wall thickness.Electric cable1512 provides electrical power for devices, provides communication service, and provides electrical power for electrical heating of fluids withinregion1516 of the coiled tubing which may be retrofitted into the steel coiled tubing to be replaced or repaired. To replacecable1512 after the steel tubing was installed into a flowline, it may be pulled out of the steel tubing leaving the steel tubing within the flowline. Then a hydraulic seal between the outside diameter of the cable and the inside diameter of the steel coiled tubing allows hydraulic pressure introduced into that annular area to be used to force down the cable into the steel coiled tubing. The outside diameter of electric cable is dependent upon the application for which it is chosen. In one preferred embodiment, hot fluid is circulated downregion1516 and the umbilical is used as an immersion heater. In another preferred embodiment, electric current goes down the electric cable and is conducted back up the coiled tubing that provides immersion heating. In yet another embodiment, all the heating comes from the power dissipated within electrical circuits within the electric cable. In yet other preferred embodiments,cable1512 may also contain fiber optic cables, hydraulic tubes, etc. for other applications.
• FIG. 47 shows yet another embodiment of the electrically heated umbilical1520 that is similar to that shown inFIG. 46, except here an extrathermal insulation layer1524 is bonded to the outside of the steel coiled tubing. Umbilical1520 is a thermally insulated umbilical with an electric cable. Here, the electric cable includes wires for heating the pipe, wires for control and power of a downhole electric pump, and fiber optic cables for measuring distributed temperature.
• FIG. 48 shows yet another embodiment of the eclectically heated umbilical1528 that is called a bundled umbilical.Outer wear sheath1532 surrounds filler orpotting material1536 which surrounds one or moreelectric cables1540. Each such electric cable provides functions described in the previous paragraph. In addition, the potting material surrounds one ormore tubes1544 havingchannels1548. The tubes may carry any fluid or chemical to the end of the umbilicals. For example, these fluids may include an emulsion breaker that is injected just upstream of a pump. The electric cables provide power and communication, and may provide distributed electrical heating. The filler binds the umbilical together and provides for control of the buoyancy of the umbilical.
• FIGS. 28 and 29 show existing flowlines installed in a producing oil field. Any of the Electric Flowline Immersion Heater Assemblies shown inFIGS. 30,31,32,33,34,35,36,37, and37A may be retrofitted into existing flowlines. The Electric Flowline Immersion Assemblies shown in these figures are different embodiments of “electric flowline immersion assembly means”. Therefore, the “Electric Flowline Immersion Heater Assembly” (“EFIHA”), the “Electric Flowline Immersion Heater Assembly with Wireline Smart Shuttle” (“EFIHAWWSS”), the “Smart Shuttle Conveyed Electric Flowline Immersion Heater Assembly (“SSCEFIHA”), and the “Pump-Down Conveyed Flowline Immersion Heater Assembly” (“PDCFIHA”), are all different embodiments of “electric flowline immersion assembly means”.
• In accordance with the preferred embodiments herein, any of the Electrically Heated Composite Umbilicals shown inFIGS. 30,31,32,33,34,35,36,37, and37A may be retrofitted into existing flowlines which are different embodiments of “electrically heated composite umbilical means” which are used to make “immersion heater means”. In accordance with the preferred embodiments herein, the additional types of electrically heated umbilical immersion heaters shown inFIGS. 41,43,45,46,47, and48 may be suitable retrofitted into existing flowlines and they are different preferred embodiments of “electrically heated umbilical means” that are used to make “immersion heater means”.
• Any of the umbilical conveyance means shown inFIGS. 30,31,32,33,34,35,36,37, and37A may be used to install any of the “electrically heated umbilical means” or the “electrically heated composite umbilical means” into a flowline to make “immersion heater means”. As described in the preferred embodiments, these are installed with different embodiments of “electric flowline immersion assembly means” which provide different means to install, or remove, the electric flowline immersion assembly means from the well. Any means that is used to convey into a flowline, or remove from a flowline, any “electrically heated umbilical means” shall be defined herein as a “conveyance means to install an electrically heated umbilical means in a flowline”. Any means that is used to convey into a flowline, or remove from a flowline, any “electrically heated composite umbilical means” shall be defined for the purposes herein as a “conveyance means to install an electrically heated composite umbilical means”.
• It is important to be able to retrofit such electrically heated immersion heater systems into existing flowlines for many reasons that includes the following:
• (a) to introduce an immersion heater system into an existing flowline that was not expected to have wax or hydrate build-up problems;
• (b) to have repair alternatives for previously installed, but failed, permanent heating systems; and
• (c) to have operating flexibility to adapt the production system to different production characteristics from original expectations.
• Electrically heated immersion heater systems can be installed to prevent waxes and hydrates from forming. Hydrates are a solid ice-like materials typically composed of water and low molecular weight gases such as methane. Hydrates form in high-pressure, low temperature, environments such as those found in subsea production systems. Hydrates may easily plug production systems, especially during transient operating conditions if not properly managed.
• In many of the preferred embodiments, a pump is installed in the flowline and may be used in combination with the electrically heated immersion heater system, which has many advantages, including the following:
• (a) such methods and apparatus increases the production recovery rate helping the field's net present value (“NPV”); and
• (b) such methods and apparatus increases the total recoverable reserves from the reservoir by reducing the backpressure on the reservoir.
• The installation of an electrically heated immersion heater system in a flowline heats up any produced heavy oils which reduces the viscosity of the produced heavy oils, which has many advantages, including the following:
• (a) such methods and apparatus reduces the pumping energy required to transport produced hydrocarbons through the flowline which therefore reduces the costs of producing the hydrocarbons;
• (b) such methods and apparatus makes some presently non-commercial fields economic to develop; and
• (c) such methods and apparatus allows for the efficient subsea transportation of typical gelling crude oils.
• In many of the preferred embodiments described, nonuniform heating may be applied to the flowline(s) by the electrically heated immersion heater system which provides many advantages, including being able to configure the production facility to better match and manage the thermal requirements for heating of the flowline(s) to avoid build up of waxes and hydrates, and to reduce the cost of producing hydrocarbons from the reservoir.
• Other preferred embodiments provide for the dynamic reconfiguring of the heat supplied by an electrically heated umbilical after the umbilical is installed into a flowline. As an example of such a preferred embodiment, the value of R(44C) inFIG. 44 can be selectable, and controlled from a surface computer. There are a variety of means for doing so, including computer controlled switches in the wall of an Electrically Heated Composite Umbilical that can be used to switch in, or out, certain resistor circuits.
• Yet other preferred embodiments provide for the dynamic reconfiguring the buoyancy of an electrical heated umbilical. For example, computer controlled valves may distribute different densities of fluids within one or more fluid channels located within the wall of an Electrically Heated Composite Umbilical. Such systems are described in detail in Provisional Patent Application No. 60/432,045, filed on Dec. 8, 2002, and in U.S. Disclosure Document No. 531,687 filed May 18, 2003, entire copies of which are incorporated herein by reference.
• In many of the preferred embodiments described, the electrically heated immersion heater system may be removed from the well, repaired, and retrofitted in the flowline without removing the flowline which provides many advantages, including the following:
• (a) such methods and apparatus saves significant operating costs by performing both the heater and artificial lift pump service from the host facility without having to mobilize a subsea intervention vessel; and
• (b) such methods and apparatus allows for the use of conventional electric submersible pumps for critical subsea “tie-back services” to the host.
• The term “tie-back service” has been used above. Satellite production wells are frequently used to develop small fields surrounding an existing facility to which they are connected, and from which they are controlled. These satellite wells provide tie-back service to the host production facility.
• In view of the above disclosure, a preferred embodiment of the invention is an apparatus comprising an electrically heated composite umbilical means installed within a subsea flowline containing produced hydrocarbons as an immersion heater means to prevent waxes and hydrates from forming within the flowline and blocking the flowline, whereby the electrically heated composite umbilical means possesses at least one electrical conductor disposed within the composite umbilical means that conducts electrical current that is used to heat the electrically heated composite umbilical means within the subsea flowline.
• In view of the above disclosure, a preferred embodiment of the invention is a method of installing an electrically heated composite umbilical means within a previously existing subsea flowline containing produced hydrocarbons to make an immersion heater means to prevent waxes and hydrates from forming within the flowline and blocking the flowline.
• In view of the above disclosure, a preferred embodiment of the invention is a method of using an umbilical conveyance means to convey into an existing subsea flowline possessing produced hydrocarbons an electrically heated composite umbilical means used as an immersion heating means to prevent waxes and hydrates from forming within the flowline and blocking the flowline.
• In view of the disclosure above, a preferred embodiment of the invention is a method of using an umbilical conveyance means to convey into an existing subsea flowline containing produced hydrocarbons an electrically heated umbilical means used as an immersion heating means to prevent waxes and hydrates from forming within the flowline and blocking the flowline.
• In view of the above, a preferred embodiment of the invention is a method of providing artificial lift to produced hydrocarbons within a subsea flowline comprising at least the steps of:
• (a) attaching a progressing cavity pump to an electric motor to make an electrically energized pump;
• (b) attaching the electrically energized pump to to a first end of a tubular composite umbilical possessing a multiplicity of electrical conductors within the wall of the tubular composite umbilical;
• (c) conveying into the flowline the electrically energized pump attached to the first end of the composite tubular umbilical;
• (d) using first and second of a multiplicity of electrical conductors to electrically heat the composite umbilical to prevent waxes and hydrates from blocking the flow of the produced hydrocarbons within the flowline; and
• (e) using at least third and fourth electrical conductors of the multiplicity of electrical conductors to provide electrical energy to the electrically energized pump, whereby the progressing cavity pump provides artificial lift to the produced hydrocarbons within the subsea flowline.
• In view of the above, a preferred embodiment of the invention is a method of providing artificial lift to produced hydrocarbons within a subsea flowline comprising at least the steps of:
• (a) attaching a hydraulic pump to an electric motor to make an electrically energized pump;
• (b) attaching the electrically energized pump to to a first end of a tubular composite umbilical possessing a multiplicity of electrical conductors within the wall of the tubular composite umbilical;
• (c) conveying into the flowline the electrically energized pump attached to the first end of the composite tubular umbilical;
• (d) using first and second of the multiplicity of electrical conductors to electrically heat the composite umbilical to prevent waxes and hydrates from blocking the flow of the produced hydrocarbons within the flowline; and
• (e) using at least third and fourth electrical conductors of the multiplicity of electrical conductors to provide electrical energy to the electrically energized pump, whereby the electrically energized pump provides artificial lift to the produced hydrocarbons within the subsea flowline.
• In yet another preferred embodiment of the invention, an electrical heated composite umbilical means dissipating in excess of 60 kilowatts of electrical energy to heat produced hydrocarbons is installed within a flowline to prevent the formation of waxes and hydrates and blockage of the flowline.
• In another preferred embodiment of the invention, an electrical heated umbilical means dissipating in excess of 60 kilowatts of electrical energy to heat produced hydrocarbons is installed within a flowline to prevent the formation of waxes and hydrates and blockage of the flowline.
• In yet another preferred embodiment of the invention, electrically heated composite umbilicals are approximately neutrally buoyant within the fluids present within the flowlines to reduce the frictional drag on the neutrally buoyant umbilicals when they are installed into the flowlines.
• Still further, in yet another preferred embodiment of the invention, electrically heated umbilicals are approximately neutrally buoyant within the fluids present within the flowlines to reduce the frictional drag on the neutrally buoyant umbilicals when they are installed into the flowlines.
• In another preferred embodiment of the invention, fluid filled electrically heated composite umbilicals are approximately neutrally buoyant within the fluids present within the flowlines to reduce the frictional drag on the neutrally buoyant umbilicals when they are installed into the flowlines.
• In yet another preferred embodiment of the invention, fluid filled electrically heated umbilicals are approximately neutrally buoyant within the fluids present within the flowlines to reduce the frictional drag on the neutrally buoyant umbilicals when they are installed into the flowlines.
• In another preferred embodiment of the invention is using the methods and apparatus to drill and complete boreholes for infrastructure purposes such as for water, sewer, electric power, and communications facilities in metropolitan areas, and for subterranean pipelines in other suitable locations.
• Offshore flowlines and pipelines are typically constructed of steel and may be insulated to minimize internal product heat losses. These pipelines are designed to lie on the ocean floor with a sufficient weight to remain stable in the subsea environment. Typically, this involves a submerged weight that is greater than 2 lbs per foot of pipe length in sea water. However, long term material fatigue problems may develop if this pipe spans different varieties of subsea terrain features. The unsupported pipe span may respond with vortex induced motion (“VIM”) if the ocean current flow is sufficiently strong and the length of span has a natural frequency that is excited by the VIM caused by the current flow. Significant costs are incurred engineering VIM solutions to remediate spans when encountered in pipelines which have already been installed.
• Most offshore pipelines have historically been located on top of the continental shelf where the terrain features are gentle and resemble coastal plains. Now, pipelines are being extended onto the continental slope where the subsea terrain more closely resembles rugged hill country. There are slot canyons, and escarpments, that are significant pipeline routing problems (to avoid unreasonably long spans). Most routing solutions are expensive to resolve for traditional steel pipelines. An alternative approach is needed that does not have these inherent problems.
• Steel flowlines and pipelines are routinely one time installations. That is, a pipeline is rarely, or never, relocated due to the high recovery and relocation cost. It is less expensive to install a completely new pipeline than to relocate an existing line. A major factor in this economic scenario is the large and expensive vessels required to install the pipelines. It is not unusual for these large vessels to lease for more than $300,000 per day and to have a substantial mobilization cost. An offshore development may easily have pipeline and flowline installation costs which represent as much as 30% to 35% of the entire field development capital expense. These substantial large vessels are required to assemble, and weld, the steel pipe into a pipeline and safely lower this pipeline to lie on the ocean floor.
• A preferred embodiment of the invention provides an alternative approach. In this preferred embodiment, a pipeline is constructed of a light-weight, strong, material so that the pipeline is buoyant, especially in deepwater where there would be no pipeline conflict with fishing interests. This buoyant pipe would be anchored to the ocean floor at strategic points along the desired route. The floating pipe would assume an arching configuration between the anchor points. The shape of the buoyant arch would be controlled by the axial tension in the pipeline itself. Any ocean currents would deflect and deform the arch in the direction of the ocean currents. A specific advantage of this configuration is that the pipeline can arch over significant seafloor terrain features like escarpments or slot canyons.
• Carefully selecting the buoyant pipe materials and insulation (while considering the range of internal products to be transported), allows the pipe to be designed to minimize VIM. On one preferred embodiment, the pipe and its contents to have a specific gravity between 0.6 and 0.9 when submerged in sea water (and is therefore, “positively” buoyant). Further, by selecting a light weight composite material, the necessary strength may be obtained, with good fatigue resistant properties, to resist the almost continuous flexing motion the pipe material will experience in service. Composite tubular products with mechanical properties that begin to approach those required for this application are currently being developed by companies like ABB Vetco Gray, Hydril, Wellstream, Fiberspar and others (in Europe), although the application of these materials to the preferred embodiments herein is a new invention as provided herein. Today, some of these manufacturers are using their composite products as shallow water flowlines. They increase the weight of the composite pipe and its internal product so that the pipe lays on the ocean floor as a one-to-one replacement for steel pipe. The novel application of using positively buoyant pipelines, and neutrally buoyant pipelines, is technically different as described in the several preferred embodiments herein.
• One preferred embodiment provides a new method of installation that uses the support of two or three relatively inexpensive anchor handling boats (a monohull vessel that may also include tugs, supply boats, etc.). The following method of installation is one several preferred embodiments that may be used to install, and commission, a buoyant, or substantially neutrally buoyant, pipeline.
• Step 1. Survey the pipeline route and select pipeline anchoring points. These are envisioned to be about 1 kilometer apart along the route. The actual distance is not critical, and spacing would be adjusted to conform to terrain features. For example one anchor point could be near the base of an escarpment, and the other on top of the escarpment, so the buoyant pipe would arch over the seafloor.
• Step 2. Mobilize anchor handling vessels and install the anchor systems at the selected locations. These anchors are envisioned to be suction anchors, but any anchor capable of resisting up-lift would be feasible to use. See the publication by H. Dendani referenced below for further discussion of suction anchors and their proper design. Aker Maritime has recently installed these anchors using only an anchor handling vessel and an ROV. Each anchor is left with a marker and a pendant to make relocation easy. Survey the anchor sites for their installed geometric locations.
• Step 3. At the pipeline shore base mobilization point, anchor clamps are installed on the pipe at the appropriate locations. These clamps feature integral strain relief devices to prevent pipeline damage at these points of pipe inflection. In one preferred embodiment, at each anchor point the pipe will be bent and the strain relief device prevents over-stress in the pipeline in this area. These clamps will be secured to the pendants rising from each of the anchors during the installation process. The clamps will be designed such that they may be installed underwater by an ROV, or repositioned along the pipe itself if needed to relocate a clamp.
• Step 4. The flexible pipeline may either be transported to site spooled on a vessel or it may be towed in the water. For the purpose of this description, it is assumed that the pipeline is towed to location from a shore based mobilization point. The pipeline is buoyant and fatigue resistant so a surface tow is practical. As with other buoyant towed installations, there will be a lead towing vessel, a following “drag” vessel, and one or two intermediate vessels alongside the floating pipeline. These vessels help maneuver the pipeline and guard the pipeline to keep other vessels from running across and damaging the towed pipeline.
• Step 5. On the installation site, a draw-down installation technique is utilized. A (synthetic) line is rigged by the ROV between a surface (traction) winch, a sheave on the end anchor and the buoyant pipe clamp. This pull-down line then draws the pipeline to the ocean floor by pulling with the winch. The ROV then connects the anchor pendent line to the appropriate anchor clamp. Meanwhile the surface vessels control the location of the surface part of the pipeline.
• Step 6. The pull-down and connection process is repeated for each anchor point along the pipeline until all anchors are attached to the pipeline.
• Step 7. The ROV spread is then used to sequentially pull the pipeline ends into their termination points and the two end connections secured. If the pipeline route is too long for a single length of pipeline, then multiple sections of buoyant pipeline may be connected together to provide the required length.
• In the above described preferred embodiment of a method to install the positively buoyant or neutrally buoyant pipeline, it is worthwhile to note that all steps of the installation process are reversible. This allows suction anchors to be relocated if required, and allows the release and recovery of the buoyant pipeline for relocation or repairs should such service ever be required. The anchor clamps may be repositioned along the pipeline if necessary.
• This installation process (using several anchor handlers and ROV's) is inexpensive compared to steel pipeline installations. The buoyant installation spread cost is sufficiently low, and the value of the pipeline material is sufficiently high, so that routine recovery and relocation of the pipeline is expected to become a common practice. In fact, this scenario may enable a long-term rental business where the lines are rented and relocated regularly. This is the current marketing model for some deepwater mooring systems, but is a new business model as proposed herein.
• Composite construction of buoyant flowline may incorporate a number of additional features. These may include integral insulation to retain the thermal energy of the fluids within the pipeline. This insulation serves as part of the flow assurance strategy for the entire production system.
• Other preferred embodiments of the invention include:
• a. Integral tubular condition monitoring sensors are incorporated into the tubular walls of the positively buoyant or neutrally buoyant pipelines. These are envisioned as fiber optic sensors monitoring the distributed stress, temperature, and/or internal pressure, or any other relevant physical parameter, in the tubular.
• b. Integral power lines for providing energy to subsea installations such as pumps are incorporated into the tubular walls of the positively buoyant or neutrally buoyant pipelines.
• c. Integral electric lines are incorporated into in the tubular walls of the positively buoyant or neutrally buoyant pipelines that are designed for heating the internal fluids within the pipeline.
• d. Integral control lines for data communication between the ends of the pipeline are incorporated into the tubular walls of the positively buoyant or neutrally buoyant pipelines.
• e. Integral fluid passages (tubes or hoses) for hydraulic service or for chemical transport to the far end of the pipeline are incorporated into the tubular walls of the positively buoyant pipelines.
• In various preferred embodiments, some, or all of these features may be integrated into the walls of the positively buoyant flowline, or neutrally buoyant flowline, so that it has sufficient functionality to meet the needs of the field being developed.
• In these preferred embodiments, the phrase “flowline” and “pipeline” may be used interchangeably.
• One preferred embodiment utilizes subsea bottom anchored buoyant pipelines that provides an “arching over terrain features” capability.
• Another preferred embodiment utilizes a low cost draw-down installation process using ROV deployed rigging.
• Such embodiments provide complete reversible installation or recovery process. This facilitates repair for damaged pipelines or for easy relocation to another area.
• Typical practices in the industry are used as set forth in the following references, entire copies of which are incorporated herein by reference:
• Dendani, H., OTC Paper #15376 entitled “Suction Anchors: Some critical aspects for their design and installation in clayey soils”, OTC 2003, Houston, Tex., May 2003.
• Eltaher, A., et. al., OTC Paper #15265 entitled “Industry Trends for Design of Anchoring Systems for Deepwater Offshore Structures”, OTC 2003, Houston, Tex., May 2003.
• InFIG. 49, all the elements through928 have been previously defined in relation toFIG. 29. In addition inFIG. 49,subsea wellhead1550 atlocation1554 on the sea bottom passes crude (oil, gas, and water) production through the positively buoyant and electricallyheated flowline1558 to the FPSO as a riser.Subsea anchor1562 supportstether1566 that is connected tofirst clamping apparatus1570.Subsea anchor1574 supportstether1578 that is connected tosecond clamping apparatus1582. The positively buoyant and electricallyheated flowline1558 passes through the first and second clamping apparatus. The positively buoyant and electricallyheated flowline1558 has aportion1586 that raises upward (or “arcs” upward) under buoyant force between the first and second clamping apparatus so as to pass overcanyon1590 in the ocean bottom. A portion of the positively buoyant and electricallyheated flowline1594 raises towards the FPSO. As described above, the positively buoyant and electrically heated flowline may be one piece, or may be comprised of many sections assembled with the assistance of one or more ROV's. Electrical power and control signals may also be passed through the walls of positively buoyant electricallyheated flowline1558 from the FPSO to thesubsea wellhead1550 that in turn may be used to provide power downhole and to monitor production within the well1598 located below thesubsea wellhead1550.
• In other embodiments of the invention, no electrical heating is provided within the positively buoyant flowline.
• FIG. 50 shows a cross section of a positively buoyant electrically heated flowline1602. Many of the elements inFIG. 50 were shown inFIG. 20, inFIG. 41, and inFIG. 43. The description in relation toFIG. 20 shows syntactic foam materials having silica microspheres as provided by the Cumming Corporation at www.emersoncumming.com (now CRP Incorporated, at www.CRPGroup.co.uk) may be used to adjust the buoyancy of the electrically heated flowline1602. As inFIG. 20, the density may be chosen to produce neutrally buoyancy in drilling mud, or in this case, may be chosen to produce substantially neutrally buoyancy, or positive buoyancy, in sea water.
• In view of the above description of preferred embodiments, a flowline for producing hydrocarbons from a subsea well has been disclosed that is comprised of a substantially neutrally buoyant tubular composite umbilical means that possesses electrical heating means within the tubular walls of the tubular composite umbilical means to prevent waxes and hydrates from forming within the flowline and blocking the flowline, whereby the electrical heating means is comprised of at least one electrical conductor disposed within the tubular walls of the composite umbilical means that conducts electrical current that is used to heat the tubular composite umbilical means, and whereby the tubular composite umbilical means that contains any produced hydrocarbons is substantially neutrally buoyant in the sea water adjacent to the subsea well.
• In view of the above description of preferred embodiments, a method of using a flowline for producing hydrocarbons from a subsea well has been disclosed that is comprised of a substantially neutrally buoyant tubular composite umbilical means that possesses electrical heating means within the tubular walls of the tubular composite umbilical means to prevent waxes and hydrates from forming within the flowline and blocking the flowline, whereby the electrical heating means is comprised of at least one electrical conductor disposed within the tubular walls of the composite umbilical means that conducts electrical current that is used to heat the tubular composite umbilical means, and whereby the tubular composite umbilical means that contains any produced hydrocarbons is substantially neutrally buoyant in the sea water adjacent to said subsea well.
• In view of the above described preferred embodiments, a flowline has been disclosed for producing hydrocarbons from a subsea well that is comprised of a substantially neutrally buoyant tubular composite umbilical means, whereby the tubular composite umbilical means that contains any produced hydrocarbons is substantially neutrally buoyant in the sea water adjacent to the subsea well.
• In view of the above described preferred embodiments, a flowline has been disclosed for producing hydrocarbons from a subsea well that is comprised of a positively buoyant tubular composite umbilical means that possesses electrical heating means within the tubular walls of the tubular composite umbilical means to prevent waxes and hydrates from forming within the flowline and blocking the flowline, whereby the electrical heating means is comprised of at least one electrical conductor disposed within the tubular walls of the composite umbilical means that conducts electrical current that is used to heat the tubular composite umbilical means, and whereby the tubular composite umbilical means that contains any produced hydrocarbons is positively buoyant in the sea water adjacent to the subsea well.
• In view of the above description of preferred embodiments, a method of using a flowline for producing hydrocarbons from a subsea well has been disclosed that is comprised of a positively buoyant tubular composite umbilical means that possesses electrical heating means within the tubular walls of the tubular composite umbilical means to prevent waxes and hydrates from forming within the flowline and blocking the flowline, whereby the electrical heating means is comprised of at least one electrical conductor disposed within the tubular walls of the composite umbilical. means that conducts electrical current that is used to heat the tubular composite umbilical means, and whereby the tubular composite umbilical means that contains any produced hydrocarbons is positively buoyant in the sea water adjacent to the subsea well.
• And finally, in view of the above described preferred embodiments, a flowline for producing hydrocarbons from a subsea well has been disclosed that is comprised of a positively buoyant tubular composite umbilical means, whereby the tubular composite umbilical means that contains any produced hydrocarbons is positively buoyant in the sea water adjacent to the subsea well.
• It is further evident from the above description that the flowlines may be used for transporting fluids between any two points. For example, one point may be on the ocean bottom, and another point may be on another portion of the ocean bottom or on the surface of the ocean.
• It is further evident from the above description that the electrically heated flowlines may be used to elevate the temperature of the fluids being transported within the flowlines. Such a temperature elevation reduces the viscosity of the transported fluids, thus requiring less energy to transport the fluids through the flowlines. The electrically heated flowlines are an example of a means to maintain transported fluids at an elevated temperature.
• While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as exemplification of preferred embodiments thereto. As have been briefly described, there are many possible variations. Accordingly, the scope of the invention should be determined not only by the embodiments illustrated, but by the appended claims and their legal equivalents.

Claims (4)

1. An apparatus comprising an electrically heated composite umbilical means installed within a subsea flowline containing produced hydrocarbons as an immersion heater means to prevent waxes and hydrates from forming within said flowline and blocking said flowline, whereby said electrically heated composite umbilical means possesses at least one electrical conductor disposed within said composite umbilical means that conducts electrical current that is used to heat said electrically heated composite umbilical means within said subsea flowline, whereby said electrical conductor is surrounded by a composite material, and whereby said composite material is comprised of fibers of high strength embedded in a matrix material, whereby said fibers are selected from carbon fibers, aramid fibers and glass fibers, and whereby said matrix material is selected from thermoset resins and thermoplastic resins, whereby said thermoset resins include epoxy and vinyl ester, and whereby said thermoplastic resins include PEEK, PEKK, and nylon.

2. A method of installing an electrically heated composite umbilical means within a previously existing subsea flowline containing produced hydrocarbons to make an immersion heater means to prevent waxes and hydrates from forming within said flowline and blocking said flowline, whereby said electrically heated composite umbilical means possesses at least one electrical conductor disposed within said composite umbilical means that conducts electrical current that is used to heat said electrically heated composite umbilical means, whereby said electrical conductor is surrounded by a composite material, and whereby said composite material is comprised of fibers of high strength embedded in a matrix material, whereby said fibers include carbon fibers, aramid fibers and glass fibers, and whereby said matrix material includes thermoset resins and thermoplastic resins, whereby said thermoset resins include epoxy and vinyl ester, and whereby said thermoplastic resins include PEEK, PEKK, and nylon.

3. A method of using an umbilical conveyance means to convey into an existing subsea flowline possessing produced hydrocarbons an electrically heated composite umbilical means used as an immersion heating means to prevent waxes and hydrates from forming within said flowline and blocking said flowline, whereby said electrically heated composite umbilical means possesses at least one electrical conductor disposed within said composite umbilical means that conducts electrical current that is used to heat said electrically heated composite umbilical means, whereby said electrical conductor is surrounded by a composite material, and whereby said composite material is comprised of fibers of high strength embedded in a matrix material, whereby said fibers include carbon fibers, aramid fibers and glass fibers, and whereby said matrix material includes thermoset resins and thermoplastic resins, whereby said thermoset resins include epoxy and vinyl ester, and whereby said thermoplastic resins include PEEK, PEKK, and nylon.

4. A method of using an umbilical conveyance means to convey into an existing subsea flowline containing produced hydrocarbons an electrically heated umbilical means used as an immersion heating means to prevent waxes and hydrates from forming within said flowline and blocking said flowline, whereby said electrically heated composite umbilical means possesses at least one electrical conductor disposed within said composite umbilical means that conducts electrical current that is used to heat said electrically heated composite umbilical means, whereby said electrical conductor is surrounded by a composite material, and whereby said composite material is comprised of fibers of high strength embedded in a matrix material, whereby said fibers include carbon fibers, aramid fibers and glass fibers, and whereby said matrix material includes thermoset resins and thermoplastic resins, whereby said thermoset resins include epoxy and vinyl ester, and whereby said thermoplastic resins include PEEK, PEKK, and nylon.

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