BACKGROUND OF THE INVENTIONThis invention relates to a new and improved hydraulic operated setting tool and liner hanger for securing a liner pipe string in a well bore preparatory to cementing the liner pipe string in place.
In the drilling or completion of wells, it is a common operation to set one or more liner hangers in a well. The liner hangers are attached to the upper end of a string of pipe and, when in position in a well, are set or anchored by mechanically or hydraulically operated mechanisms. A hydraulic, pressure set liner hanger has certain advantages in that it does not require mechanical movements of pipe and is, more of less, a positively set tool. In any hydraulically set mechanism for a liner hanger, it is, of course, desirable to reduce the possibility of fluid leaks in the liner hanger.
The present invention involves a hydraulically actuated setting tool and liner hanger which minimize the possibility of a malfunction or wrongful operation of the tool by only requiring one pressure operation for setting the liner hanger, and one operation for release of the setting tool from the liner hanger. The liner hanger is an integral member without ports and without special pressure sealing surfaces for the setting tool. All of the hydraulic pressure ports are in the setting tool so that the liner hanger is reduced to simply a body and slips. Since the entire setting tool can be retrieved, it is economical to recover the setting tool and service it. Also the setting tool and liner hanger are adaptable to re-working operations because the liner hanger has no specially ground surfaces.
SUMMARY OF THE INVENTIONIn accordance with a preferred embodiment of the present .[.information.]. .Iadd.invention.Iaddend., a liner hanger is provided with spring biased slips and is connected to a hydraulic setting tool by a threaded release nut connection. The setting tool has a retrievable pack-off bushing which seals off the bore of the liner hanger from passage of fluid. A pressure operated sleeve on the setting tool body is shear pinned to the body and normally holds the slip elements in a retracted position. When pressure is applied to the sleeve, the sleeve is moved upon shearing of the shear pins to release the slip elements so they may be set in the pipe. Rotation of the mandrel of the tool releases the release nut connection so that the tool mandrel can be moved upwardly. Upward movement of the tool mandrel .[.releases.]. .Iadd.retrieves .Iaddend.the pack-off bushing from the liner bore and the entire setting tool assembly is retrieved.
In another embodiment of the invention, a single spiral slip element is used as an anchoring mechanism. To set the spiral slip element, the pressure operated sleeve is actuated to mechanically set the slip element upon movement in an upward direction.
It is accordingly an object of the present invention to provide a new and improved hydraulic pressure set tool and liner hanger which will be operative under a wide range of operating conditions without having malfunctions.
Other objects and advantages of the present invention will become more readily apparent from the following detailed description which when read in conjunction with the accompanying drawings illustrate the invention, and wherein in the drawings:
BRIEF DESCRIPTION OF THE DRAWINGSFIGS. 1A and 1B conjunctively illustrate, in longitudinal cross section, the setting tool and liner hanger of the present invention in a "going in" position in a well casing;
FIGS. 2A and 2B conjunctively illustrate in longitudinal cross section, the setting tool and liner hanger after pressure has been applied to the tool;
FIGS. 3A and 3B conjunctively illustrate in longitudinal cross section, the position of elements of the setting tool and liner hanger after operation of the release mechanism and release of the setting tool from the liner hanger;
FIGS. 4A and 4B conjunctively illustrate in longitudinal cross section, the position of the setting tool in an elevated position with respect to the liner hanger to illustrate the release of the latching mechanism;
FIG. 5 illustrates, in longitudinal cross section, a liner hanger in a set position in a casing;
FIG. 6 illustrates, in a horizontal cross section, the apparatus when taken alongline 6--6 of FIG. 1A.
FIG. 7 illustrates, in horizontal cross section, the apparatus when taken alongline 7--7 of FIG. 1B;
FIG. 8 is a view in horizontal cross section taken along line 8--8 of FIG. 2B;
FIG. 9 illustrates an outer view of the tool in a "going in" position of the apparatus;
FIGS. 10A and 10B are conjunctive views, in longitudinal cross section, through a tool which represent another embodiment of the present invention. On the vertical right-hand side of FIGS. 10A and 10B, the outer configuration of the tool is illustrated and, on the vertical left-hand side from the center line, the cross section of the tool is illustrated.
DESCRIPTION OF THE INVENTIONReferring now to the drawings where common numerals indicate common elements, theliner hanger 10 is shown in FIG. 5 in a "set" position in tubular casing orpipe 11. Theliner hanger 10 includes atubular hanger body 13 which has acenter bore 14. Thecenter bore 14 has anannular locking recess 15 disposed intermediate of the length of thebore 14. Thelocking recess 15 is formed from a section of enlarged diameter. At the upper end of thecenter bore 14 is an enlargeddiameter portion 16 which terminates at its upper end with a threadedportion 17. On the outside, upper end of thehanger body 13, are three, angularly spaced longitudinal pads 18 (see FIG. 6) which respectively have longitudinal grooves therein for guiding elongatedslip retaining members 20, as will hereinafter be more fully explained. Intermediate of the length of the outer surface of thehanger body 13 are three, circumferentially spacedslip members 22. The slips orslip members 22 are connected by common tapered, dovetail connections to cone or taperedsurfaces 23 on thehanger body 13. Theslips 22 are shown in an extended position is FIG. 5 with outer serrated surfaces in engagement with thecasing 11. Theslips 22 are resiliently biased in their extended position byspring members 24 which are disposed incylindrical recesses 25. Thesprings 24 are arranged in compression so that when the slips are released, the springs normally urge theslip members 22 into gripping engagement with the wall of acasing 11. At the lower end of theliner hanger body 13 is a threadedconnection 28 which is adapted for connection to the upper end of a liner pipe.
To set theliner hanger body 13 in position in a .[.wall.]. .Iadd.well .Iaddend.casing 11 as shown in FIG. 5, a hydraulic setting tool is provided. The setting tool of the present invention includes atubular mandrel 30 comprised of anupper section 35, anintermediate section 36 and a lower section 37 (FIGS. 1A and 1B). Theupper section 35 has atubular coupling sub 31 at its upper end. Themandrel 30 is adapted, at itslower section 37 for threaded coupling by means of acoupling sub 32 to a section of tubing (not shown). For purposes of explanation, thesub 32 is illustrated with an internal shoulder 33 to catch asolid sealing ball 34. In actual practice, theball 34 is seated on a shoulder in a ball catcher (not shown) which is attached to the tubing (not shown). The purpose of theball 34 seating on the shoulder 33 is to permit fluid pressure to be applied to the interior of the tubular assembly above the sealing ball.
Theupper section 35 has an enlarged outer portion which has stepped diameter portions. On the first diameter steppedportion 40 is atubular sleeve 41 of apressure cylinder 42. Shear pins orshear screws 43 provide a releasable connection between thepressure cylinder 42 and the steppedportion 40. On the next intermediate stepped portion is apacking element 45 which provides a pressure seal between thesleeve 41 and the steppedportion 40. A stop-nut 47 is threadedly received on thesection 35 for retaining thepacking element 45 in a fixed position. Thetubular sleeve 41 has aportion 50 of reduced diameter which is slidably received on the outer wall of theupper mandrel section 35. The reducedportion 50 has apacking element 51 disposed in sealing relationship with respect to the outer wall of themandrel section 35.
Ahousing 42a is threadedly attached to thepressure cylinder 42. In thehousing 42a is aplunger recess 52, which has a springbiased pin member 53 arranged to resiliently bear against the outer wall ofsection 35. Between the packing elements, 45 and 51, theupper mandrel section 35 has apressure port 54 through a wall which is adapted to pass fluid from the interior of thesection 35 to the interior of thecylinder 42 to act upon thepressure cylinder 42 and to move thecylinder 42 in an upward direction upon the application of sufficient pressure to shear thepins 43. Just below thecoupling sub 31, theupper section 35 has anannular latching groove 55 which is adapted to receive the latch-pin member 53 when the cylinder is in an upper position on thesection 35 and to lock thepressure cylinder 42 in an upper position.
Theintermediate section 36 of the mandrel has steppeddiameter portions 60 and 61. The first reducedportion 60 carries a settingtool release nut 62. The release nut (see FIG. 6) has interior flattened surface portions which match outer flat surfaces on themandrel section 36 so that themandrel section 36 can slide longitudinally with respect to thenut 62 yet impart rotational torque to thenut 62. The upper portion ofdiameter portion 61 is cylindrical shaped and is adapted to rotatably receive the upper end of anut housing 65. Thenut housing 65 is separated with respect to the upper section by arotative bearing member 63. Aspring 64 is disposed between the nut housing and the setting tool nut. Thesetting tool nut 62 is threadedly attached to the threadedportion 17 of theliner hanger body 13. Thetubular end 62a of thenut housing 65 abuts an internal shoulder disposed in the upper end of theliner hanger body 13. The interior of thenut housing 65 is sized to receive thenut 62 when it is moved upwardly relatively to themandrel section 36.
On thelower mandrel section 37, apackoff bushing member 70 is disposed between themandrel section 37 and the liner hanger body 13 (See FIG. 1B). The pack-offbushing member 70 has inner and outerannular sealing members 71, 72 for sealing engagement with the outer wall of themandrel section 37 and theinner bore 14 of theliner hanger body 13. In addition, thebushing member 70 has an attached latch housing 70a with four circumferentially spaced, latch members 75 (see FIG. 7) received inslots 76 in the latch housing 70a. Thelatch members 75 normally are received in theannular recess 15 in the body member 13 (see FIG. 1B) and extend between the outer wall of the mandrel section 39 and into therecess 15 so that thebushing member 70 is effectively locked in position with theliner hanger body 13. Below thelower mandrel section 37 is an outer, recessedannular portion 77 which is used to release and allow thelatches 75 to retract from therecess 15 in thebody member 13. Thelatches 75 are held in place byring member 78.
Thepressure cylinder 42 has attached elongatedvertical strap members 20 which extend along the outside of the nut housing and throughvertical guide grooves 18 on the liner hanger body (see FIG. 6). In the position of the tool as illustrated in FIGS. 1A and 1B, the lowermost ends of thestraps 20 engage the uppermost ends of theslip members 22. Theslip members 22, when so engaged by thestrap members 20 are held in a retracted position on the tool body and thesprings 24 behind the slip members are normally compressed.
As illustrated in FIGS. 1A, 1B, and FIG. 9, the tool can be run into the well bore through thecasing 11 to a position where it is desired to set theliner hanger 10. The interior bore of the liner hanger is closed off by the pack-offbushing 70.
As shown in FIGS. 2A and 2B, when it is desired to set theliner hanger 10, a pressure ball 34 (see FIG. 1B for illustration of position) is dropped through the tubing string and to close off the bore of the pipe below thepressure ports 54 in the upper mandrel. With the bore of the mandrel and tubing string above the ball being pressure sealed or closed, when fluid pressure is applied to the interior of the tubing string it acts through thepressure ports 54 upon thepressure cylinder 42. The pressure on thepressure cylinder 42 causes the shear pins 43 to be fractured and thepressure cylinder 42 moves upwardly until it abuts or engages thecoupling 31, (see FIG. 2A and 2B). In the upper position of thepressure cylinder 42, thelatch pin 53 engages the lockinggroove 55 and locks thepressure cylinder 42 in its uppermost position. Movement of thepressure cylinder 42 in an upward direction relative to themandrel section 30 causes thestraps 20 to be raised upwardly .Iadd.and separated from theslip members 22 .Iaddend.thereby releasing theslip members 22 from their retracted position so that thesprings 24 can force theslip members 22 outwardly into engagement with the wall of thecasing 11. Force can then be applied in a downward direction through thecoupling sub 31, themandrel section 35, thebearing 63, thenut housing 65 and thebody member 13 to set the slips firmly in position within the pipe.
To retrieve the setting tool, the tubing attached to thecoupling 31 is rotated in a clockwise direction which causes the settingnut 62 to rotate out of its threaded position with respect to theliner hanger body 13 against the force of thespring 64 and to ride up into the recess within the nut housing 65 (see FIG. 3A). When thenut 62 clears the threadedconnection 17 on theliner hanger body 13, the setting tool has been operatively disconnected from theliner hanger 10 and the tubing can be raised in an upward direction.
When the tubing andcoupling 31 are raised in an upward direction, as shown in FIGS. 4A and 4B, thelower mandrel section 37 also is raised until thecoupling 32 contacts lower bushing member 70a and the reduceddiameter portion 77 is positioned adjacent to thelatch members 75. Continued upward movementforces latching members 75 from theannular recess 15 and into their slotted cavity within the lower bushing section 70a. This action releases thebushing housing 70 with respect from theliner hanger body 13 and permits retrieval of the entire setting tool.
In FIGS. 10A and 10B, another embodiment of the present invention is illustrated which utilizes aliner hanger 80 having a singlespiral slip element 81 arranged on aspiral cam groove 82 in theliner hanger body 83. Remaining components of the tool and hanger which are similar to the hanger and tool as heretofor described and are identified with similar members.
Thevertical straps 20 are attached to theslip element 81 by a shear pins 85 so that upon the movement of thepressure cylinder 50 toward its upward position, thestraps 20 carry theslip element 81 upwardly into engagement with the wall of the casing and thereafter shear thepins 85 to release thestraps 20 from theslip element 81. Further construction details of the spiral slip element and cam groove are disclosed in my copending application Ser. No. 079,037 filed Sept. 26, 1979 and entitled "Liner Hanger Assembly".
While only selected embodiments of the present invention are illustrated and described herein, other embodiments of the invention are contemplated and many changes and modifications of the inventions may be made within the scope of the appended claims without departing from the spirit of the invention.