INTELLIGENT WELL SAND CONTROL
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of an earlier filing date from U.S.
Provisional Application Serial No: 60/280,587 filed April 2, 2001, the entire disclosure of which is incorporated herein by reference.
BACKGROUND
Technical Field [0002] The disclosure relates to oil field gravel pack systems and methods for their use. More particularly, the disclosure relates to multiple sand control assemblies with single zone control.
Prior Art [0003] Sand control apparatus, systems and methods have been an important part of wells for hydrocarbon production for an extended period and are used to support boreholes in unconsolidated formations as well as to cause particulate matter (such as sand) entrained in production fluid to bridge at the sand control assembly and thus be excluded from the tubing of the well. Unfortunately prior art sand control assemblies, in order to obtain individual zone control employ an inner assembly which reduces the LD. of the string available for other purposes. Without the inner assembly individual zonal control is not possible.
SUMMARY
[0004] Multizone sand control assemblies with flow control for individual zones can be achieved while maintaining a full bore LD. of the sand control assembly.
The sand control assemblies that make the realization of these benefit possible comprise individual components that are commercially available but which have not heretofore been combined. The effect of the combination as taught herein is synergistic and produces results of significant benefit to the art such as the mentioned individual control whether the control is far production fluids or remediation fluids;
and in one embodiment produces superior gravel packing. The assembly includes a string of spaced apart packers, with a sump packer at a most downhole location for the string. The packers are interspersed by gravel pack screen sections and sliding sleeves (the number of sleeves depends upon the embodiment). In addition, a blank pipe section is located radially inwardly of each screen section in both of the discussed embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Referring now to the drawings wherein like elements are numbered alike in the several Figures:
0006 Figures 1 and 2 is an elongated view in quarter section of a gravel pack flow control assembly; and 0007 Figures 3 and 4 is an alternate elongated view imquarter section of a gravel pack flow control assembly.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
(0008] Two embodiments are disclosed herein which provide control in a multizone sand control assembly . Control is with respect to fluids flowing into the well through individual or selective groups of zones and for sealing off selected zones during remediation treatment to avoid damaging or contaminating zones not in need of remediation. Consequently, such control also alleviates the unnecessary loss of expensive remediation fluids which in some prior art systems are needlessly and profitlessly lost into the formation. In addition, for one of the embodiments discussed herein, the control gained by the particular assemblies discussed enhances an active gravel packing procedure by alleviating bridging otherwise caused by rapid "dehydration" of the gravel pack slurry (usually gravel and a liquid carrier) to the formation. The use of either of the assemblies described herein preferably follows conventional perforating and fracturing operations. In each embodiment, recirculation of excess proppant out of the well after fracturing is preferred.
[0009] In a first embodiment, referring to Figures l and 2, a multiple zone sand control assembly 10 is illustrated with three zones 12a, 12b and 12c. A
sump packer 14 is located at a downhole end of the assembly 10 as illustrated. Sump packer 14, in one embodiment , is installed in the well in a distinct run on preferably wireline to facilitate deployment in a desired location. Alternatively, sump packer 14 could be made a part of assembly 10. Assembly 10 is otherwise installed as a single assembly in one run in the hole. Where sump pump 14 is installed in a separate run, assembly 10 is stabbed into sump packer 14 with locator tubing seal assembly 16.
Preferably assembly 10 is constructed at a surface location with spacing sufficient to locate a plurality of screens included therein proximate perforations 18 in casing 20 which were created in the perfoz~ating operation.
[00010] Locator tubing seal assembly 16 is connected to a valve 22, preferably an intelligent production regulator (IPR) valve commercially available from Baker Oil Tools, Houston, Texas. IPR valves preferably comprise a valve for regulating flow of a fluid in addition to pressure sensors. One pressure sensor is located upstream of the valve and one pressure sensor is located downstream of the valve. IPR valve 22 is connected through a shroud 24 and sliding sleeve 26 to a bypass packoff sub 28 having a flow conduit 30 therein which communicates with annular space 32 between shroud 24 and sleeve 26. Radially inwardly and sealed to sub 28 is tubing 34.
Tubing 34 is preferably sealed to sub 28 with one or more o-rings 36. Connected at an uphole end of sub 28 is crossover sub 38 having pin and box threads at downhole and uphole ends thereof, respectively.
[00011] Crossover sub 38 is connected at its uphole end to a screen 40. It should be noted that between screen 40 and tubing 34 is defined an annular flow area 42, which area is fluidly connected to conduit 30 in sub 28 and thereby to annular space 32. Fluid flowing in the spaces defined is conveyable to an LD. 43 of the pack assembly 10 through one or more flow ports 44 controlled by IPR valve 22 via sleeve 46. It should further be noted that such flow may also be conveyed to the LD.
43 of pack assembly 10 through one or more ports 48 in sliding sleeve 26 controlled by manually operable sleeve 50 which generally would be used in the event IPR
valve 22 did not function as intended.
[00012] Referring back to screen 40 and tubing 34, both elements are preferably connected at an uphole end thereof to double pin sub 52 which in turn is connected to a blank pipe section 54. Blank pipe section 54 is connected to a retrievable packer 56.
[00013] Each of the ensuing uphole portions of sand control assembly 10 bear similar numerals (one hundred and two hundred series of the same numbers) since the individual components illustrated are identical to those described above.
[00014] A preferred concise procedure for installation of the above-discussed embodiment is as follows:
1. Set sump packer below planned lower zone perforations.
2. Perforate lower zone.
3. Perform hydraulic fracture treatment in lower zone:
4. Leave sand plug across lower zone and perforate middle zone.
5. Perform hydraulic fracture treatment in middle zone.
6. Leave sand plug across middle zone and perforate upper zone.
7. Perform hydraulic fracture treatment in upper zone.
8. Wash sand out of casing using PERFFLOW pills as required to control fluid loss.
9. Run isolation packers, screens and IPR valves as illustrated with valves closed.
10. Stab into sump packer and pressure tubing to set isolation packers.
11. Open IPR valves and bring well on production (frac sand will flow back and fill annulus between screen and casing).
[00015] Assembly 10, having been installed in a well casing 20 after a fracturing and a recirculation cleanout procedure, is intended to receive a natural gravel pack. As one of skill in the art will recognize, many thousands of pounds of proppant (usually sand or gravel) is pumped into perforation zones in a well for the .
fracturing operation. Thus, far more than a sufficient quantity of proppant exists adjacent perforations 18 and in perforations 18 after the recirculating clean out of the well to satisfy the need for proppants in a "natural gravel pack" operation.
Once assembly 10 is set, IPR valve 22 is opened and the well is allowed to flow. By the action of this flow, proppants left in the perfs 18 and in the vicinity thereof and which are not propping fractures open are driven toward screen 40 where they are "dehydrated" against the screen while wellbore fluids pass therethrough.
Proppants continue to be drawn to the screen and in the direction of gravity to the next packer until the annular space 58 between packer 56 and sump packer 14 is filled with proppant. The wellbore fluid flowing through screen 40 is conveyed via annular flow area 42 through conduit 30 to annular space 32 and through port 44, preferentially, or port 48 into assembly LD. 43 and to an uphole location. This is the condition in which the zone will operate during normal well production, however in order to facilitate natural gravel packing of the other zones 12b, 12c (two illustrated but not so limited),1PR valve 22 is preferably closed. The process for zone 12b begins as did the process for zone 12a with the opening of an Il'R valve 122 (one hundred series of same numerals). Upon completion of the natural gravel packing operation of zone 12b a similar process will preferably occur in zone 12c and so on for any remaining zones.
[00016] Subsequent to the natural gravel packing operation, one or more of the IPR valves 22, 122, 222 may be opened to produce the well. It should be noted that each of the IPR valves is preferably addressable and operable from a remote location.
[00017] Facilitating remote location actuation is preferably a TEC (tubing encapsulated conductor) 60 extending from the remote location to each IPR
valve. Of course it will be appreciated that other means of communicating with the IPR
valves remotely can be substituted such as but not limited to fiber optic conductors hydraulic 1 S line, etc.
[00018] The assembly 10 affords control in each zone of a multizonal sand control assembly individually, collectively or in any combination to promote or hinder production from that zone. Additionally, the capability of remotely controlling each zone allows for controlling the loss of expensive fluids intended to have an effect on one or more zones but not others. Moreover, remote control allows for protection of the perforations from harmful remediation activities needed in one or more but not all zones. Furthermore, the embodiment maintains a full bore LD. of the assembly which facilitates both higher production rate capability and allows larger tools or strings to pass through the assembly 10 to or from more downhole locations.
[00019] In another embodiment, referring to Figures 3 and 4, a frac and park assembly 310 is illustrated. Since the great majority of components of assembly 310 are common to the embodiment of Figures 1 and 2, the three hundred, four hundred and five hundred series numerals thereon will suffice in combination with the foregoing explanation to explain the portions of the assembly not specifically addressed in the paragraphs subsequent hereto.
[00020) The embodiments of Figures 3 and 4 differ from the foregoing embodiment in areas bounded by double pin sub 352 and blank pipe 354. The . . CA 02377857 2002-03-21 distinction is the interconnection of additional blank pipe 362 and sliding sleeve 364 having port 366 and manually actuatable sleeve 368. Sleeve 368 is actuable by a conventional crossover tool (not shown).
[00021] In keeping with the foregoing information, the following is a concise list of procedures for installing the second embodiment discussed herein.
Operations relevant to the assembly 310 are further discussed hereunder. The concise procedure is as follows:
1. Set sump packer below planned lower zone perforations.
2. Perforate lower zone.
3. Perform hydraulic fracture treatment in lower zone.
4. Leave sand plug across lower zone and perforate middle zone.
5. Perform hydraulic fracture treatment in middle zone.
6. Leave sand plug across middle zone and perforate upper zone.
7. Perform hydraulic fracture treatment in upper zone.
8. Wash sand out of casing using PERFFLOW pills as required to control fluid loss.
9. Run isolation packers, screens and IPR valves as illustrated with valves closed.
10. Stab into sump packer and pressure tubing to set isolation packers.
11. Run crossover tool with selective shifting tool on coiled tubing and open lower CMD sliding sleeve.
12. Position crossover tool across lower CMD sliding sleeve.
13. Open lower IPR valve and circulate gravel pack into screen/casing annulus until screenout.
14. Pick-up crossover tool and circulate out excess gravel.
15. Pull out of hole with crossover tool and close lower CMD sliding sleeve and IPR.
16. Run crossover tool with selective shifting tool on coiled tubing and open middle CMD sliding sleeve.
17. Position crossover tool across middle CMD sliding sleeve.
18. Open middle IPR valve and circulate gravel pack into screen/casing annulus until screenout.
_7-19. Pick-up crossover tool and circulate out excess gravel.
20. Pull out of hole with crossover tool and close middle CMD sliding sleeve and IPR.
21. Run crossover tool with selective shifting tool on coiled tubing and open upper CMD sliding sleeve.
22. Position crossover tool across upper CMD sliding sleeve.
23. Open upper IPR valve and circulate gravel pack into screenlcasing annulus until screenout.
24. Pick-up crossover tool and circulate out excess gravel.
25. Pull out of hole with crossover tool and close upper CMD sliding sleeve and IPR.
26. Open IPR, valves and bring well on production.
00022 Assembly 310, like assembly 10, is run in the hole and set subsequent to perforating and fracturing operations as well as recirculating cleanout of proppants left in the LD. of casing 20. The sand control operation in this embodiment however includes an active gravel packing operation in that a gravel slurry is directed into annulus 58 through the crossover tool having had its discharge port (not shown) aligned with port 366 in sliding sleeve 364. IPR valve 322 is opened and gravel laden slurry is propagated toward screen 340 through port 366 from the crossover tool (not shown). Upon reaching screen 340 and particularly starting at a downhole end of screen 340, gravel or other sand control material is "dehydrated" due to the carrier fluid being drawn off through screen 340 to annular flow area 358; through fluid conduit 330 to annular space 332 through port 344 preferentially or port 348 secondarily to assembly 310; LD. 343 for delivery back to the crossover sub and to an uphole location. Gravel packing continues until a pressure drop downhole of the screen or pressure spike uphole of the screen is detected. Pressure conditions are detectable by the IPR valve using sensors as indicated above and/or by an additional sensor located preferably uphole of the sliding sleeve 364 and dowrihole of the zones uphole defining packer 356, 456 and 556. A sensor is schematically illustrated in Figures 3 and 4 and is numbered 370, 470 and 570 in the respective zones. Upon detected pressure change, pumping of the slurry is halted. The following action of pulling the crossover tool uphole to the next zone closes sleeve 368. IPR
valve 322 is _g_ also preferably closed to completely seal off zone 312 while packing operations proceed in zones 312b and 312c sequentially. It should be noted that this embodiment, as in the foregoing embodiment, maintains a full bore LD. of the gravel pack assembly 310 which allows for higher flow rates of sand control pack carrying fluid back to an uphole location than was possible in the prior art due to a restricted diameter return flow tube. This creates a better gravel pack by avoiding potential bridging caused by slurry flowing out to the reservoir faster than it could move up the return. In addition this embodiment is endowed with the beneficial features of the foregoing embodiment including remote control.
00023 While preferred embodiments of the invention have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described byway of illustration and not limitation.
What is claimed: