The present invention relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides a setting tool for an expandable liner hanger and associated methods.
Expandable liner hangers are generally used to secure a liner within a previously set casing or liner string. These types of liner hangers are typically set by expanding the liner hangers radially outward into gripping and sealing contact with the previous casing or liner string. Many such liner hangers are expanded by use of hydraulic pressure to drive an expanding cone or wedge through the liner hanger, but other methods may be used (such as mechanical swaging, explosive expansion, memory metal expansion, swellable material expansion, electromagnetic force-driven expansion, etc.).
The expansion process is typically performed by means of a setting tool used to convey the liner hanger and attached liner into a wellbore. The setting tool is interconnected between a work string (e.g., a tubular string made up of drill pipe or other segmented or continuous tubular elements) and the liner hanger.
If the liner hanger is expanded using hydraulic pressure, then the setting tool is generally used to control the communication of fluid pressure, and flow to and from various portions of the liner hanger expansion mechanism, and between the work string and the liner. The setting tool may also be used to control when and how the work string is released from the liner hanger, for example, after expansion of the liner hanger, in emergency situations, or after an unsuccessful setting of the liner hanger.
It is desirable to minimize a wall thickness of the setting tool and liner hanger assembly, so that equivalent circulating density (ECD) is reduced, and so that the assembly can be conveyed rapidly into the well.
It will, therefore, be appreciated that improvements are needed in the art of expandable liner hanger setting tools and associated methods of installing expandable liner hangers. These improvements can include improvements to reduce ECD during running in, to increase operational efficiency, convenience of assembly and operation, improved functionality, etc., whether or not discussed above.
In carrying out the principles of the present invention, a setting tool and associated methods are provided which solve at least one problem in the art. One example is described below in which the setting tool uses multiple expansion cones to expand different portions of the liner hanger. Another example is described below in which the setting tool is provided in multiple sections which are assembled while running the liner hanger and setting tool into the well.
In one aspect, a method of conveying an expandable liner hanger in a subterranean well is provided. The method includes the steps of: conveying the liner hanger into the well on a work string with a setting tool releasably secured to the liner hanger by an anchoring device; applying left-hand rotation to the work string; and then lowering the work string, thereby releasing the anchoring device and permitting the setting tool to be retrieved from within the liner hanger.
In another aspect, a method of setting an expandable liner hanger in a subterranean well is provided which includes the steps of: forcing an expansion cone through a portion of the liner hanger, thereby expanding the liner hanger portion radially outward; and forcing another expansion cone into another portion of the liner hanger, thereby expanding the second liner hanger portion radially outward.
In yet another aspect, a method of setting an expandable liner hanger in a subterranean well is provided which includes the steps of: lowering a liner into the well; then connecting the liner hanger and a lower section of a setting tool to the liner; then lowering the liner hanger and the lower section into the well; and then connecting an upper section of the setting tool to the lower section.
In a further aspect, a method of setting an expandable liner hanger in a subterranean well is provided which includes the steps of: applying a pressure differential between an inner flow passage of a setting tool and an annulus formed between the setting tool and a wellbore, the pressure differential causing the setting tool to begin to expand the liner hanger; and applying a biasing force to a bypass closure as a result of the pressure differential acting on a piston area of the bypass closure, thereby causing the bypass closure to displace and provide fluid communication between the flow passage and the annulus.
These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention hereinbelow and the accompanying drawings, in which similar elements are indicated in the various figures using the same reference numbers.
It is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of the present invention. The embodiments are described merely as examples of useful applications of the principles of the invention, which is not limited to any specific details of these embodiments.
In the following description of the representative embodiments of the invention, directional terms, such as “above”, “below”, “upper”, “lower”, etc., are used for convenience in referring to the accompanying drawings. In general, “above”, “upper”, “upward” and similar terms refer to a direction toward the earth's surface along a wellbore, and “below”, “lower”, “downward” and similar terms refer to a direction away from the earth's surface along the wellbore.
Representatively illustrated in
Note that, in this specification, the terms “liner” and “casing” are used interchangeably to describe tubular materials which are used to form protective linings in wellbores. Liners and casings may be made from any material (such as metals, plastics, composites, etc.), may be expanded or unexpanded as part of an installation procedure, and may be segmented or continuous. It is not necessary for a liner or casing to be cemented in a wellbore. Any type of liner or casing may be used in keeping with the principles of the present invention.
As depicted in
A setting tool 20 is connected between the liner hanger 18 and a work string 22. The work string 22 is used to convey the setting tool 20, liner hanger 18 and liner 16 into the wellbore 14, conduct fluid pressure and flow, transmit torque, tensile and compressive force, etc. The setting tool 20 is used to facilitate conveyance and installation of the liner 16 and liner hanger 18, in part by using the torque, tensile and compressive forces, fluid pressure and flow, etc. delivered by the work string 22.
At this point, it should be specifically understood that the principles of the invention are not to be limited in any way to the details of the system 10 and associated methods described herein. Instead, it should be clearly understood that the system 10, methods, and particular elements thereof (such as the setting tool 20, liner hanger 18, liner 16, etc.) are only examples of a wide variety of configurations, alternatives, etc. which may incorporate the principles of the invention.
Referring additionally now to
The liner hanger 18 and setting tool 20 are shown in
The setting tool 20 is releasably secured to the liner hanger 18 by means of an anchoring device 28 (see
The anchoring device 28 can be conveniently released at the conclusion of the setting operation as described more fully below. Briefly, the work string 22 can be lowered after the setting operation to thereby cause the support sleeve 36 to displace downward, so that the support sleeve no longer outwardly supports the collets 30, enabling the setting tool 20 to be retrieved from within the liner hanger 18.
In addition, the anchoring device 28 can be released, even if the setting tool 20 has not successfully set the liner hanger 18, by rotating the work string 22 to the left (counter-clockwise as viewed from the surface) and then downwardly displacing the work string.
The work string 22 is connected to a generally tubular inner mandrel assembly 44 through which the flow passage 40 extends. The threaded connection 24 (between the work string 22 and the setting tool 20) is at an upper end of the inner mandrel 44 assembly (see
The support sleeve 36 is part of the inner mandrel assembly 44, which is prevented from displacing downwardly relative to the outer housing assembly 48 by dogs or engagement members 38. However, if sufficient downward force is applied to an outer release sleeve 84 to cause shear screws 46 to shear, the release sleeve will be permitted to displace downwardly, releasing the members 38 from their engagement with the inner mandrel assembly 44, and the inner mandrel assembly (including the support sleeve 36) will displace downwardly, thereby unsupporting the collets 30 and allowing them to disengage from the recesses 32.
In
To apply the downwardly directed force to the release sleeve 84, the work string 22 is used to rotate an upper connector housing 86 counter-clockwise, and to then downwardly displace the connector housing. Inner lugs 88 formed in the connector housing 86 are engaged with a ratchet or J-slot profile 90 formed externally on the inner mandrel assembly 44.
Typically, the engagement between the lugs 88 and the J-slot profile 90 prevents downward displacement of the connector housing 86 relative to the inner mandrel assembly 44, but if the connector housing is first rotated counter-clockwise, so that the lugs 88 enter a downwardly elongated portion of the J-slot profile 90, then the connector housing can displace downwardly relative to the inner mandrel assembly. The connector housing 86 can then contact and apply a downwardly directed force to the release sleeve 84, thereby shearing the shear screws 46, releasing the members 38, and enabling the inner mandrel assembly 44 to displace downwardly relative to the outer housing assembly 48 as discussed above.
In
Note that the setting tool 20 can be released from the liner hanger 18 at any time. For example, the anchoring device 28 would typically be released after the liner hanger 18 is set in the casing string 12 (i.e., by lowering the work string 22 to downwardly displace the support sleeve 36, and then raising the work string to withdraw the setting tool 20 from the liner hanger), or the anchoring device could be released as a contingency procedure in the event that the liner 16 gets stuck in the wellbore 14 (i.e., by rotating the work string counter-clockwise, then lowering the work string to release the members 38 and downwardly displace the support sleeve, and then raising the work string to withdraw the setting tool 20 from the liner hanger).
Returning to
The increased pressure differential is applied across three pistons 60 interconnected in the outer housing assembly 48 (see
A venting device 70 is provided to vent the flow passage 40 to the annulus 52 if a pressure differential across the venting device reaches a predetermined limit. The venting device 70 is representatively illustrated in the drawings as a rupture disk, but other types of venting devices, pressure relief devices, etc. may be used, if desired.
An expansion cone 66 is positioned at a lower end of the outer housing assembly 48. The expansion cone 66 is depicted as a two-piece element having a lower frusto-conical surface 68 formed thereon which is driven through the interior of the liner hanger 18 to outwardly expand the liner hanger. The term “expansion cone” as used herein is intended to encompass equivalent structures which may be known to those skilled in the art as wedges or swages, whether or not those structures include conical surfaces.
Note that only a small upper portion of the liner hanger 18 overlaps the expansion cone 66. This configuration beneficially reduces the required outer diameter of the setting tool 20 and liner hanger 18 assembly, which thereby reduces the equivalent circulating density while circulating through the assembly, and enables the assembly to be conveyed more rapidly into the well.
The differential pressure across the pistons 60 causes each of the pistons to exert a downwardly biasing force on the expansion cone 66 via the remainder of the outer housing assembly 48. These combined biasing forces drive the expansion cone 66 downwardly through the interior of the liner hanger 18, thereby expanding the liner hanger.
Although three of the pistons 60 are illustrated in the drawings and described above, any greater or lesser number of pistons may be used. If greater biasing force is needed for a particular setting tool/liner hanger configuration, then more pistons 60 may be provided. Greater biasing force may also be obtained by increasing a piston area of each of the pistons 60.
The setting tool 20 and liner hanger 18 are representatively illustrated in
In another important feature of the setting tool 20, another expansion cone 72 is provided on an exterior of the outer housing assembly 48. This additional expansion cone 72 engages an upper end 76 of the liner hanger 18 at the conclusion of the setting process, to thereby provide a smooth, enlarged entry for subsequent access to the interior of the liner 16 after the setting tool 20 is retrieved. Once expanded by the cone 72, the upper end 76 of the liner hanger 18 has a larger inner diameter D than the inner diameter d of the liner hanger as expanded by the lower expansion cone 66.
Note that, when the outer housing assembly 48 has displaced downward a predetermined distance relative to the inner mandrel assembly 44, a bypass closure 94 will be contacted and displaced downward by the outer housing assembly to thereby open ports 74 and provide fluid communication between the exterior of the setting tool 20 and an internal chamber 78 exposed to a lower side of one of the pistons 60 (see
An alternative way of downwardly displacing the bypass closure 94 is to increase pressure in the passage 40 above the plug sufficiently to shear one or more shear screws 96. The bypass closure 94 has an internal differential pressure area formed therein which causes the sleeve to be biased downwardly by the pressure differential from the passage 40 to the annulus 52. Preferably, the shear screw 96 is configured so that the pressure differential required to shear the shear screw is greater than that required to displace the expansion cone 66 and expand the liner hanger 18 sufficiently, but is less than the pressure differential required to open the venting device 70.
The bypass closure 94 will, thus, displace downwardly after the shear screw 96 has sheared, thereby opening the ports 74. A snap ring 98 will prevent the sleeve 94 from displacing upward to close the ports 74. In
Note that, if during a normal setting operation the outer housing assembly 48 is displaced downwardly sufficiently far relative to the inner mandrel assembly 44, so that the outer housing assembly contacts and biases the bypass closure 94 downwardly, it merely needs to shear the shear screw 96. Once the shear screw 96 is sheared, the differential pressure across the piston area in the sleeve 94 will cause the sleeve to displace downward further to open the ports 74. In this manner, the sleeve 94 opens a relatively large flowpath, and does so relatively quickly, thereby minimizing any erosive effects caused as the pressure in the flow passage 40 is equalized with the pressure in the annulus 52.
With the liner hanger 18 expanded as depicted in
The setting tool 20 is quite long when assembled so, for purposes of convenient handling, storage, transport, etc., the setting tool includes features which enable it to be assembled as the liner 16, liner hanger 18 and setting tool are being installed into the wellbore 14. In particular, separate sections of the outer housing assembly 48 and inner mandrel assembly 44 can be connected together as the setting tool 20 is being installed.
In
The liner 16 and liner hanger 18 have been lowered into the well, and slips 54 of a drilling rig (not shown) now support the liner, liner hanger and the lower section of the setting tool 20. A spacer block 56 supports a coupling 80a of the inner mandrel assembly 44a in position above a coupling 82 of the outer housing assembly 48a. This keeps the inner mandrel assembly 44a from displacing downwardly relative to the outer housing assembly 48a, which would otherwise operate to release the anchoring device 28. A lift coupling 100 is temporarily connected to an upper end of the coupling 80a for use in lifting the lower section of the setting tool 20 and the liner hanger 18, so that they can be connected to the liner 16 when it is suspended in the slips 54.
Referring additionally now to
Referring additionally now to
Referring additionally now to
By providing the setting tool 20 in multiple sections which can be easily, quickly and conveniently assembled as the setting tool, liner hanger 18 and liner 16 are being installed in the well, storage and transport of the setting tool is made more practical and economical. For example, the separate sections of the setting tool 20 can more readily be accommodated on standard trucks, boats and other shipping means, can more readily be hoisted onto an offshore rig, can be more readily stored, can be more easily assembled, etc.
It may now be fully appreciated that the system 10, setting tool 20 and associated methods described above provide significant improvements in the art of setting expandable liner hangers. These improvements include, but are not limited to, the use of the additional expansion cone 72 to enlarge the upper end 76 of the liner hanger 18, the provision of the contingency release wherein a counter-clockwise (left-hand) rotation of the work string 22 followed by lowering the work string operates to release the anchoring device 28, the bypass closure 94 which opens a large flow area quickly, and the assembly of upper and lower sections of the setting tool as it is being installed in the well.
The above disclosure, in particular, provides a method of setting an expandable liner hanger 18 in a subterranean well, with the method including the steps of: lowering a liner 16 into the well; then connecting the liner hanger 18 and a lower section 44a, 48a of a setting tool 20 to the liner 16; then lowering the liner hanger 18 and the lower section 44a, 48a into the well; and then connecting an upper section 44b, 48b of the setting tool 20 to the lower section 44a, 48a.
The step of connecting the upper section of the setting tool 20 to the lower section of the setting tool 20 may include connecting an upper section 48b of an outer housing assembly 48 to a lower section 48a of the outer housing assembly 48.
The step of connecting the upper section of the setting tool 20 to the lower section of the setting tool 20 may also include the step of connecting an upper section 44b of an inner mandrel assembly 44 to a lower section 44a of the inner mandrel assembly 44 prior to the step of connecting the upper section 48b of the outer housing assembly 48 to the lower section 48a of the outer housing assembly 48.
The method may include the step of releasably securing the upper section 48b of the outer housing assembly 48 to the upper section 44b of the inner mandrel assembly 44 prior to the step of connecting the upper section 48b of the outer housing assembly 48 to the lower section 48a of the outer housing assembly 48.
The method may also include the step of displacing the outer housing assembly 48 relative to the inner mandrel assembly 44 to thereby expand the liner hanger 18.
Also provided by the above disclosure is a method of setting an expandable liner hanger 18 in a subterranean well, with the method including the steps of: forcing a first expansion cone 66 through a first portion of the liner hanger 18 (e.g., at the seals 206), thereby expanding the first portion radially outward; and forcing a second expansion cone 72 into a second portion of the liner hanger 18 (e.g., at the upper end 76), thereby expanding the second portion radially outward.
The second portion may be an end 76 of the liner hanger 18. The first and second expansion cones 66, 72 may be longitudinally spaced apart along a setting tool 20 received in the liner hanger 18.
The first expansion cone 66 forcing step may include expanding the liner hanger 18 first portion to a first internal dimension d, the second expansion cone 72 forcing step may include expanding the liner hanger 18 second portion to a second internal dimension D, and the second internal dimension D may be greater than the first internal dimension d. The second internal dimension D may be formed by the second expansion cone 72 at an end 76 of the liner hanger 18.
The above disclosure also describes a method of setting an expandable liner hanger 18 in a subterranean well, with the method including the steps of: applying a pressure differential between an inner flow passage 40 of a setting tool 20 and an annulus 52 formed between the setting tool 20 and a wellbore 14, the pressure differential causing the setting tool 20 to begin to expand the liner hanger 18; and applying a biasing force to a bypass closure 94 as a result of the pressure differential acting on a piston area of the bypass closure 94, thereby causing the bypass closure to displace and provide fluid communication between the flow passage 40 and the annulus 52.
The biasing force applying step may include displacing an outer housing assembly 48 relative to an inner mandrel assembly 44 of the setting tool 20, thereby causing the outer housing assembly 48 to contact the bypass closure 94.
The biasing force applying step may include increasing the biasing force to a predetermined level to thereby shear a shear member 96.
Also described by the above disclosure is a method of conveying an expandable liner hanger 18 in a subterranean well, with the method including the steps of: conveying the liner hanger 18 into the well on a work string 22 with a setting tool 20 releasably secured to the liner hanger 18 by an anchoring device 28; applying left-hand rotation to the work string 22; and then lowering the work string 22, thereby releasing the anchoring device 28 and permitting the setting tool 20 to be retrieved from within the liner hanger 18.
The anchoring device 28 may secure an inner mandrel assembly 44 of the setting tool 20 relative to the liner hanger 18. The step of applying left-hand rotation may include rotating the work string 22 relative to the inner mandrel assembly 44.
The step of rotating the work string 22 relative to the inner mandrel assembly 44 may include displacing a lug 88 in a J-slot 90.
The step of lowering the work string 22 may include releasing an engagement member 38 which previously prevented displacement of the inner mandrel assembly 44 relative to the outer housing assembly 48.
Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the invention, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to these specific embodiments, and such changes are within the scope of the principles of the present invention. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents.