US20100108323A1 - Reliable Sleeve Activation for Multi-Zone Frac Operations Using Continuous Rod and Shifting Tools - Google Patents

Abstract

An apparatus for opening and closing downhole tools, such as sliding sleeves, includes a first (opening) shifting tool connected to an end of a continuous rod, an intermediate rod connected below the first shifting tool, and a second (closing) shifting tool connected to the end of the intermediate rod. The first tool has a profile for selectively opening sleeves when moved downhole, and the second tool has a profile for selectively closing sleeves when moved uphole. Alternatively, a single tool can couple to the end of the continuous rod and can have the profiles for opening and closing sleeves. When used, the continuous rod and shifting tools are deployed downhole to a series of sliding sleeves on a tool string. Manipulated by the continuous rod and a rig at the surface, the shifting tools are used to successively open and close the sliding sleeves so that successive isolated zones of a formation can be treated with frac fluid.

Description

BACKGROUND
• Selectively fracing multiple zones of a formation improves the production capabilities of a well. The equipment string for such a frac operation uses a series of packers to sequentially isolate different zones of a downhole formation. Sliding sleeves on the tubing string position between each of the packers and provide exit ports for frac fluid to interact with the adjacent zones of the formation. Performing successive frac treatments on the isolated zones requires the sliding sleeves to be opened and closed in a desired sequence so that zones of interest can be fraced independently of the other zones. To do this, the frac operation uses several steps. First, one sliding sleeve is opened, while the others remain closed. Frac fluid is pumped downhole and through the open sleeve to interact with the adjacent zone of the formation. When facing is done for this zone, the sliding sleeve is then closed, and another sliding sleeve is opened so the next zone can be treated.
• Sliding sleeves can be activated using many types of devices, including balls, darts, and pulling tools. Currently, operators experience problems when performing frac operations For example, the number of zones that can be treated may be limited by the method used to actuate the sleeves. Also, operators can have difficulties ensuring that the proper sleeve is open for the frac treatment and then that the proper sleeve is closed and sealed after that treatment. This difficulty can be even more problematic when fracing a horizontal well.
• When balls are used to actuate the sliding sleeves, for example, the frac treatment is applied successively to each isolated zones by selectively opening the sliding sleeves and allowing the treatment fluid to interact with the adjacent zones of the formation. To open each sliding sleeve, operators drop a specifically sized ball into the tubing string and land the ball on a corresponding ball seat on a designated sliding sleeve. Once seated, the ball closes off the lower zone just treated, and built up pressure on the seated ball forces the sliding sleeve open so frac fluid can interact with the adjacent zone of the formation. Operators repeat this process up the tubing string by successively dropping larger balls against larger ball seats in the sliding sleeves.
• The required diameters of the ball seats and the required increments between ball sizes limits how many zones can be treated using balls to open the sliding sleeves. For example, the lowermost ball seat must be the smallest, and each shallower seat must be sized slightly larger. In general, the balls can range in size from 1-in. to 3¾-in. Therefore, only a finite number of frac zones can be successfully used when opening the sleeves with balls due to the needed increments between ball sizes to differentiate them from one another. Therefore, actuating sliding sleeves with balls is not practical for frac operations involving several (e.g., more than about eleven) frac zones. In addition to the limit on the number of frac zones that can be handled, using balls and darts to open sliding sleeves only allows for one shot operations. In other words, the balls and darts are only capable of opening the sleeves, which cannot be closed unless another device is used. Finally, any balls and darts used to operate sleeves must be removed either by floating or milling them, which involves time and expense to perform.
• Other than balls and darts, a pulling tool connected to wireline can be used to actuate sliding sleeves during a frac operation. However, actuating sliding sleeves using wireline can be limited in horizontal sections downhole. In many cases, wireline has no real pushing capabilities, which limits its use in operating sliding sleeves or other flow control systems within a wellbore.
• Using coiled tubing can overcome the limitations of wireline. Unfortunately, a pulling tool on coiled tubing can still have limited access in extended horizontal wellbores, making it difficult for the pulling tool to reach sliding sleeves in horizontal sections. This difficulty is due at least in part to the fact that coiled tubing has some memory inherent in its material. Therefore, the coiled tubing as it is run downhole with the pulling tool is more likely to produce friction within the tubing string in which it is run, making moving the coiled tubing and the pulling tool more difficult. When used under these circumstances, the coiled tubing requires operators to spend an excessive amount of time to locate and subsequently open or close a sliding sleeve—sometime without success altogether. Furthermore, coil tubing is expensive and is preferably removed from the tubing string with each frac treatment to avoid damage to the coil tubing. Finally, the physical nature of coiled tubing inherently limits the coil tubing's ability to operate sliding sleeves by pushing. All of these issues greatly increase the time and cost of performing a frac operation with coiled tubing and make coiled tubing less desirable for operating sliding sleeves.
• What is needed is a solution for cycling sliding sleeves open and closed in extended horizontal applications that can be better manipulated from the surface and that is more reliable in opening and closing the sleeves downhole.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a schematic view of a system using continuous rod and a tool actuating device.
• FIG. 2A shows a cross-section of a sliding sleeve in a closed condition.
• FIG. 2B shows a cross-section of the sliding sleeve in an opened condition.
• FIG. 3 shows a tool actuating device on an end of a continuous rod.
• FIG. 4A shows an isolated cross-section of an upper (opening) shifting tool for the tool actuating device.
• FIG. 4B shows a cross-section of the upper (opening) shifting tool having the continuous rod and an intermediate sucker rod coupled at its ends.
• FIG. 5 shows a cross-section of a lower (closing) shifting tool for the tool actuating device.
• FIG. 6A shows the upper (opening) shifting tool opening a sliding sleeve initially in the closed (up) condition.
• FIG. 6B shows the lower (closing) shifting tool closing a sliding sleeve initially in the opened (down) condition.
• FIGS. 7A-7E shows stages of actuating sliding sleeves with the tool actuating device.
• FIGS. 8A shows another tool actuating device.
• FIG. 8B shows a cross-section of the tool actuating device ofFIG. 8A.
DETAILED DESCRIPTION
• Asystem10 schematically shown inFIG. 1 uses acontinuous rod40 and atool actuating device60 to actuate downhole tools during well operations. In the current example, thesystem10 is used in conjunction with frac operations, and thecontinuous rod40 andtool actuating device60 allow operators to selectively open and close slidingsleeves50 downhole. In the typical implementation as shown, acased borehole12 passes through a formation, and atool string14 installed in theborehole12 has severalsliding sleeves50 positionedadjacent perforations13 at various intervals in thecased borehole12.Packers20 isolate portions of theannulus15 of theborehole12 andstring14 between each section of peroratedborehole12. In this way, frac fluid pumped down thetool string14 can be diverted by an open slidingsleeve50 through theisolated perforations13 to treat the isolated zone of the formation.
• As shown, the casedborehole12 can have an extended horizontal section that makes actuating the slidingsleeves50 difficult with conventional coiled tubing or wireline techniques. To overcome these difficulties, thetool actuating device60 is disposed on the distal end of thecontinuous rod40, and therod40 anddevice60 are used together to effectively and reliably open and close the slidingsleeves50 in such an extended horizontal section. (Thesystem10 can be used equally as well in vertical applications). In general, thetool actuating device60 can be moved up or down in thestring14 to selectively actuate a givensleeve50 between opened and closed conditions by engaging specific profiles on thedevice60 with profiles in thesleeve50. The rigidcontinuous rod40 stiffly conveys the desired movement of thedevice60 relative to thesleeves50, making the opening and closing of thesleeves50 more predictable and ensuring that more complete travel of thesleeves50 is achieved.
• As noted previously, coiled tubing has some memory inherent in its material and produces undesirable friction when conveyed in a horizontal borehole. As a result, operators must spend an unwarranted amount of time attempting to locate and actuate the sliding sleeves downhole—sometimes with no success. However, thecontinuous rod40 attempts to straighten out in thetubing string14 and produces a lower friction component. The reduced friction allows operators to move thetool actuating device60 as needed with better control from the surface. In this way, therod40 anddevice60 facilitate frac operations in the horizontal length of the borehole.
• As shown, thecontinuous rod40 deploys in thetool string14 to convey thedevice60 downhole to the slidingsleeves50. At the surface, arig30 for extended continuous rod is used to manipulate (raise and lower) thecontinuous rod40 in thestring14 and thereby move theactuating device60 relative to the slidingsleeves50. Thisrig30 can be similar to that used with extended continuous rod. For example, therig30 can include a reel for thecontinuous rod40 and a variable-speed, hydraulically driven gripper mechanism (not shown), and therig30 can be adapted to operate like a heavy duty slickline unit at the surface to deploy thecontinuous rod40 anddevice60 downhole. In addition to therig30, other components (not shown), such as wellhead, lubricator, etc., are also used at the surface.
• The slidingsleeves50 can be selectively opened and closed to divert frac fluid in thetubing string14 to the isolated zone of theannulus15 betweenpackers20. Anexample sliding sleeve50 shown inFIG. 2A has ahousing52 with aninsert54 movably disposed therein. When closed as shown inFIG. 2A, theinsert54 is positioned toward the lower end of thehousing52. In this position,slots55 in theinsert54 do not align withports53 in the side of thehousing52 so that fluid passing in thesleeve50 is not diverted outside thesleeve50 and the tubing to which it is coupled at both ends. When opened as shown inFIG. 2B, theinsert54 is positioned toward the upper end of thehousing52. In this position, theslots55 in theinsert54 align with theports53 in the side of thehousing52 so that fluid passing in thesleeve50 can be diverted outside thesleeve50.
• To move theinsert54 between the opened and closed conditions, theinsert54 has alower profile56 and anupper profile58 that allow theinsert54 to be engaged and moved within thehousing52. For thepresent sleeve50, thelower profile56 is used to move theinsert54 downward in thehousing52, thereby closing thesleeve50. By contrast, theupper profile58 is used to move theinsert54 upward in thehousing52, thereby opening thesleeve50. A reverse arrangement is also possible in which upward movement of theinsert54 by theupper profile58 can close thesleeve50 and downward movement by thelower profile56 can open thesleeve50.
• With an understanding of thesystem10,continuous rod40, slidingsleeves50, andtool actuating device60 provided above, discussion now turns to a more detailed description of thetool actuating device60. As shown inFIG. 3, thetool actuating device60 couples to a threadedpin42 on thecontinuous rod40. At top, thedevice60 has an upper (opening) shiftingtool100 that couples to the rod's threadedpin42 using arod coupling70. At bottom, thedevice60 has a lower (closing) shiftingtool200 that couples below theupper tool100 usingrod couplings70 and an intermediate length ofsucker rod80. When thecontinuous rod40 is moved upper or down in a tubing string, the upper andlower tools100/200 move together.
• In the present example, theupper tool100 is designed to be the opening tool for opening the slidingsleeves50 by engaging the upper profile (58) and shifting the insert (54) upward in the housing (50). (SeeFIGS. 2A-2B). Likewise in this example, thelower tool200 is designed to be the closing tool for closing the slidingsleeves50 by engaging the lower profile (56) and shifting the insert (54) downward in the housing (50). (SeeFIGS. 2A-2B). Thus, theupper shifting tool100 opens thesleeve50 by jarring up, and thelower shifting tool200 closes thesleeve50 by jarring down. However, a reverse arrangement could also be used. For example, the arrangement oftools100 and200 on thedevice60 could be switched so that the (closing) shiftingtool200 can be the upper tool and the (opening) shiftingtool100 can be the lower tool. Congruent with this, the slidingsleeves50 could also be open and closed by respectively shifting down and up—opposite to that shown inFIGS. 2A-2B.
• The upper (opening) shiftingtool100 shown inFIG. 4A has acore mandrel110 withfishneck couplings102 and104 threaded at both ends. Abiased collet120 fits around the mandrel's recessedintermediate portion116 and connects at both ends tostops112 and114 fixed to thecore mandrel110. Thecollet120 has B-profiles122 that include an upward facingshoulder124, an upper (shortened)cam126, and a lower (extended)cam128. As discussed in more detail later, the B-profiles122 enable thecollet120 to engage recessed profiles in the sliding sleeve in one direction and bypass the recessed profiles in the sliding sleeve in the opposite direction. This type of shifting tool is typically referred to as a B shifting tool with a B-profile.
• As shown inFIG. 4B, the upper (opening) shiftingtool100 couples to thedistal end42 of thecontinuous rod40 using asucker rod coupling70. As shown, thiscoupling70 has acylindrical body72 withinternal thread74 that connects to the rod's threadedpin42 and to thepin103 on the tool'supper fishneck coupling102. Thesucker rod coupling70 can usethread74 that is preferably cold form-rolled as opposed to cut and can use the PRO/KC design available from Weatherford/Lamb, Inc. As shown, thecoupling70 can also use acenter torque button76 positioned between the threaded pins42/103 of therod40 andfishneck102 for equal contact pressure of both pin noses. In a similar fashion, anothersucker rod coupling70 couples the tool'slower fishneck104 to the upper pin on the device'sintermediate sucker rod80.
• As withupper tool100, the lower (closing) shiftingtool200 shown inFIG. 5 includes similar components, including acore mandrel210 with afishneck coupling202 threaded at its top and including acollet220 fitting around the mandrel's recessedintermediate portion216 and connected at both ends tostops212 and214 fixed to thecore mandrel110. Thetool200 has anose204 at its distal end. Thecollet220 has B-profiles222 that include ashoulder224, anupper cam226, and alower cam228. For thisclosing tool200, however, the B-profile222 is reversed so that theshoulder224 is downward facing and theupper cam228 is extended.
• Operation of the upper tool's B-profile122 in opening a slidingsleeve50 is shown inFIG. 6A. Operators manipulate theupper tool100 upward in the sleeve'shousing52 using thecontinuous rod40 and rig equipment at the surface. The B-profile's (upward-facing)shoulder124 engages a downward-facing shoulder in the insert'supper recess profile58. When engaged, further upward movement of thetool100 moves theinsert54 upward withinhousing52 toward an opened condition in which the insert's slots align with the housing's ports so fluid can be diverted. Eventually, full upward movement on thetool100 causes the upper cam (126) to engage anupper release59 defined in thehousing52, biasing thecollet120 inward and releasing theshoulder124 from the insert'sprofile58. At this point, thetool100 can move out of thehousing52 while theinsert54 remains in the opened (upward) condition.
• Operation of the lower tool's B-profile222 in closing the slidingsleeve50 is shown inFIG. 6B and follows a reversed configuration. Here, the B-profile's (downward-facing)shoulder224 engages an upward-facing shoulder in the insert'slower recess profile56. When engaged, further downward movement of thetool200 moves theinsert54 downward withinhousing52 toward a closed condition. Eventually, the lower cam (228) engages alower release57 so theshoulder224 is released and thetool200 can move out of thehousing52 while the insert remains in the closed (downward) condition.
• As discussed above, thecontinuous rod40 andtool actuating device60 can be deployed by asurface rig30 to open and close sliding sleeves during a frac operation. In stages of a frac operation shown inFIG. 7A-7E, thetool actuating device60 selectively actuates the various slidingsleeves50 downhole by successively opening and closing thesleeves50 to treat isolated zones. Using thecontinuous rod40 to manipulate thedevice60 is more reliable than using coiled tubing, which would tend to produce more friction and would require more time to actuate thesleeves50.
• As initially shown inFIG. 7A, the slidingsleeves50 are deployed on thestring14 downhole before the frac operation. Operators couple theupper shifting tool100 to the distal end of thecontinuous rod40, couple theintermediate rod80 to the bottom of theupper tool100, and coupled thelower shifting tool200 to the free end of theintermediate rod80. Operators then install thedevice60 in a lubricator fitted atop the wellhead at the surface and deploy thecontinuous rod40 andselective shifting tools100/200 downhole using the drive and other components of the rig (30; SeeFIG. 1).
• When lowered, thetools100/200 are passed through each of the slidingsleeves50A-C, which are initially installed closed on thestring14. Thesleeves50A-C may be deployed with grease or other material packed inside to maintain the sliding inserts (54) in the closed condition in thesleeves50A-C during deployment. As thetools100/200 are deployed downhole, they cam past each of the sleeves' inserts (54) without engaging the profiles (56,58). Eventually, the upper (opening)tool100 passes into the lowermost slidingsleeve50A. Using a upward jarring movement, the upper (opening)tool100 opens the lowermost slidingsleeve50A by engaging the collet's B-profiles (122) into the insert's upper recess (58) (SeeFIG. 6A). A jar (not shown) installed on thecontinuous rod40 or the rig (30) at the surface can impart this jarring movement. Once thesleeve50A opens and the B-profiles (122) cams free, thecontinuous rod40 andtools100/200 are moved below the openlowermost sleeve50A, as shown inFIG. 7B.
• As then shown inFIG. 7B, operators perform a frac treatment by pumping frac fluid down thetool string14 while thecontinuous rod40 remains in thetubing sting14. Leaving thecontinuous rod40 and shiftingtools100/200 in thestring14 during the frac treatment below theopen sleeve50A eliminates the rig time that would be required to trip thetools100/200 androd40 out of thesting14 between frac treatments, as would conventionally be done to protect coiled tubing if used to actuate the sleeves.
• During treatment, the frac fluid diverts through theopen sleeve50A and treats the adjacent isolated zone though theperforations13. Once this zone has been treated, operators use the rig to lift thecontinuous rod40 in thestring14. As shown inFIG. 7C, theupper tool100 freely passes through the lowermost slidingsleeve50A that remains open. With further lifting, the lower (closing)tool200 is positioned to engage this open slidingsleeve50A. Using a downward jarring movement, thelower tool200 closes thislowermost sleeve50A.
• As shown inFIG. 7D, thedevice60 androd40 are then lifted in thetubing string14, and the upper (opening)tool100 engages the nextuppermost sliding sleeve50B (which is closed). Using an upward jarring movement, thetool100 is used to open thissleeve50B. As shown inFIG. 7E, once theupper tool100 cams free, operators position the twotools100/200 in between the slidingsleeves50A-50B, pump frac fluid in thestring14, and treat the next isolated zone adjacent theopen sleeve50B. Once fracing is complete for this zone, operators lift thetools100/200 and again close the open slidingsleeve50B, open the next upper most slidingsleeve50C, and frac the next zone. Operations then continue in this same manner up thestring14 as each successively higher isolated zone is treated.
• Although the frac operation discussed above involved opening thesleeves50 in the uphole direction and closing them in the downhole direction, the reverse arrangement could be used. Likewise, treatment of successive zones could proceed successively from the uppermost zone to the lowermost zone or could be performed selectively at any of the various zones. In addition, although thedevice60 andcontinuous rod40 are initially deployed from the surface downhole to thelowermost sleeve50A in the above discussion, it is also possible to deploy thedevice60 independently in a bottomhole assembly (not shown) coupled in a conventional manner to thetubing string14 below the lower most slidingsleeve50A. In this case, thecontinuous rod40 can then be deployed downhole with a suitable coupling known in the art to connect to thedevice60 and retrieve if from the bottomhole assembly to conduct the successive frac operations up the wellbore.
• Thetool actuating device60 ofFIG. 3 uses upper andlower shifting tools100 and200 separated by anintermediate sucker rod80. Another arrangement of thedevice60 can uses a two-way shifting tool300 as shown inFIGS. 8A-8B. Here, the two-way shifting tool300 couples to the threadedpin42 of thecontinuous rod40 using asucker rod coupling70. The two-way tool300 includes many of the same components as the upper and lower tools discussed previously so that thetool300 includes acore mandrel310, afishneck coupling302, stops312/314, abiased collet320, and anose304. On thistool300, thecollet320 has dual B-profiles322 having a downward-facingshoulder324, anupper cam326, an upward-facingshoulder325, and alower cam328. Depending on the sleeve's configuration, the shiftingtool300 can open/close the sleeve by jarring down and can close/open the sleeve by jarring up. Thistool300 can be used for selective frac treatments of isolated zones in a similar fashion to that discussed above with reference toFIGS. 7A-7E.
• In general, thecontinuous rod40 used with thesystem10 can be COROD® and can have similar properties and characteristics. (COROD is a registered trademark of Weatherford/Lamb Inc.—the assignee of the present disclosure). For example, thecontinuous rod40 can be composed of carbon steel, chromium-molybdenum alloy steel (e.g., AISI 4142), or other suitable material and can have round or semi-elliptical cross-section with a diameter ranging from 12/16-inch to 18/16-inch, for example.
• As shown inFIGS. 2A-2B and6A-6B, thesystem10 when used for frac operations can be used with a mono-bore type of sliding sleeve, but other types of sliding sleeves could also be used. Examples of suitable sliding sleeves include the Otimax™ Sliding Sleeve, the Optislim™ Sliding Sleeve, and WXO and WXA Standard Sliding Sleeves, each of which are products of Weatherford/Lamb, Inc.—assignee of the present application.
• Although thesystem10 has been described for opening and closing sliding sleeves on a frac string, the system ofcontinuous rod40 andtool actuating device60 can also be used to actuate other downhole tools that can be actuated to a first operative condition in a first direction and to a second operative condition in a second direction. Some other suitable downhole tools include, for example, a gravel pack closing sleeve, a completion isolation valve, or other downhole tool having shiftable operation. With any of these downhole tools, the ability to actuate the tool with thecontinuous rod40 andactuating device60 can be enhanced by the reliable and efficient operation that therod40 anddevice60 offer in either vertical or horizontal wells.
• The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.

Claims (20)

1. A downhole tool actuating method, comprising:

installing a first shifting tool to an end of a continuous rod, the first shifting tool adapted to selectively actuate a downhole tool in a first direction to a first operative condition;

installing an intermediate rod below the first shifting tool;

installing a second shifting tool to an end of the intermediate rod, the second shifting tool adapted to selectively actuate a downhole tool in a second direction to a second operative condition;

deploying the continuous rod and the first and second shifting tools downhole to a downhole tool; and

selectively actuating the downhole tool to either the first or the second operative condition by moving the first and second shifting tools with the continuous rod in either the first or second directions relative to the downhole tool to selectively actuate the downhole tool with either the first or second shifting tool.

2. The method ofclaim 1, wherein the downhole tool is a sliding sleeve having an insert movable between opened and closed conditions.

3. The method ofclaim 1, wherein installing the first shifting tool to the end of the continuous rod comprises coupling a first threaded pin on the continuous rod to a second threaded pin on the first shifting tool using a sucker rod connector.

4. The method ofclaim 1, wherein installing the intermediate rod comprises coupling a first threaded pin of a sucker rod to a second threaded pin of the first shifting tool using a sucker rod connector.

5. The method ofclaim 1, wherein selectively actuating the downhole tool to the first operative condition comprises:

engaging an uphole facing shoulder on the first shifting tool against a downhole facing shoulder on the downhole tool; and

selectively actuating the downhole tool to an opened condition by moving the first shifting tool in an uphole direction.

6. The method ofclaim 5, wherein selectively actuating the downhole tool to the opened condition further comprises camming the uphole facing shoulder free from the downhole facing shoulder against a first stop shoulder in the downhole tool.

7. The method ofclaim 5, wherein selectively actuating the downhole tool to the second operative condition comprises:

engaging a downhole facing shoulder on the second shifting tool against an uphole facing shoulder on the downhole tool; and

selectively actuating the downhole tool to a closed condition by moving the second shifting tool in a downhole direction.

8. The method ofclaim 7, wherein selectively actuating the downhole tool to the closed condition further comprises camming the downhole facing shoulder free from the uphole facing shoulder against a second stop shoulder in the downhole tool.

9. A sliding sleeve actuating method, comprising:

installing at least one shifting tool on an end of a continuous rod, the at least one shifting tool adapted to selectively actuate a downhole tool in a first direction to a first operative condition and in a second direction to a second operative condition;

deploying the continuous rod and the at least one shifting tool downhole to a downhole tool; and

selectively actuating the downhole tool to either the first or second operative condition by moving the at least one shifting tool with the continuous rod in either the first or second directions relative to the downhole tool to selectively actuate the downhole tool with the at least one shifting tool.

10. The method ofclaim 9, wherein selectively actuating the downhole tool to the first operative condition comprises:

engaging a first shoulder on the at least one shifting tool facing a first direction against a second shoulder on the downhole tool facing a second opposite direction; and

selectively actuating the downhole tool to the first operative condition by moving the at least one shifting tool in the first direction.

11. The method ofclaim 10, wherein selectively actuating the downhole tool to the first operative condition further comprises camming the first shoulder free from the second shoulder against a first stop shoulder in the downhole tool.

12. The method ofclaim 10, wherein selectively actuating the downhole tool to the second operative condition comprises:

engaging a second shoulder on the shifting tool facing the second direction against a first shoulder on the downhole tool facing the first opposite direction; and

selectively actuating the downhole tool to the second operative condition by moving the at least one shifting tool in the second direction.

13. The method ofclaim 12, wherein selectively actuating the downhole tool to the second operative condition further comprises camming the second shoulder free from the first shoulder against a second stop shoulder in the downhole tool.

14. A formation fracing method, comprising:

deploying a continuous rod downhole to a plurality of sliding sleeves, the continuous rod having at least one shifting tool adapted to selectively open and close a sliding sleeve in opposing first and second directions;

selectively opening and closing the sliding sleeves by moving the at least one shifting tool with the continuous rod in the first and second opposing directions relative to the sliding sleeves; and

fracing selective zones of the formation isolated by packers disposed downhole between each of the sliding sleeves by using the at least one shifting tool and the continuous rod to successively open and close the sliding sleeves in the selective zones.

15. The method ofclaim 14, wherein deploying the continuous rod downhole comprises installing one shifting tool on an end of the continuous rod, the one shifting tool adapted to selectively open the sliding sleeve in the first direction and to selectively close the sliding sleeve in the second direction.

16. The method ofclaim 14, wherein deploying the continuous rod downhole comprises:

installing a first shifting tool to an end of the continuous rod;

installing an intermediate rod below the first shifting tool; and

installing a second shifting tool to an end of the intermediate rod.

17. The method ofclaim 16, wherein the first shifting tool is adapted to selectively open the sliding sleeve in the first direction, and wherein the second shifting tool is adapted to selectively close the sliding sleeve in the second direction.

18. A downhole tool actuating system, comprising:

a continuous rod having a distal end;

a surface rig operable to deploy and move the continuous rod in first and second directions downhole; and

a tool actuating device coupleable to the distal end of the continuous rod, the tool actuating device having a first profile adapted to selectively actuate a downhole tool in the first direction to a first operative condition, the tool actuating device having a second profile adapted to selectively actuate the downhole tool in the second direction to a second operative condition.

19. The system ofclaim 18, wherein the tool actuating device comprises:

a first shifting tool coupleable to the distal end of the continuous rod and having the first profile;

an intermediate rod having first and second ends, the first end coupleable to the first shifting tool; and

a second shifting tool coupleable to the second end of the intermediate rod and having the second profile.

20. The system ofclaim 18, wherein the tool actuating device comprises a shifting tool coupleable to the distal end of the continuous rod, the shifting tool having the first and second profiles.

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