US2980185A - Retrievable well tool hanger - Google Patents

Description

April 18, 1961 D. E. DAFFIN RETRIEVABLE WELL TOOL HANGER 2 Sheets-Sheet 2 Filed July 11, 1958 INVENTOR.

ATTORNEY United States Patent RETRIEVABLE WELL TOOL HANGER Douglas E. Datfin, Pasadena, Tex., assignor to Cameo Incorporated, Houston, Tex., a corporation of Texas Filed July 11, 1958, Ser. No. 747,980

8 Claims. (Cl. 166-211) This invention relates to an improved well tool hanger which can be easily lowered in the well string on a wire line and securely latched at a given location for supporting a subsurface control device, an extension tube or the like, and which hanger can be readily removed at any later time. Tool hangers as heretofore constructed have often been somewhat complex and costly to manufacture and have been difiicult to handle from the surface through a flexible line without the exercise of considerable skill in effecting a proper landing at a presumed location and thereafter in careful manipulation to drive a projecting wedge force behind initially retracted latch do s.

in object of the present invention is to provide in a simplified form a retrievable tool hanger having normally projected dogging or locking mechanism which responds by its fit to and relative travel in a landing section for conditioning itself to an automatic latching operation coincidental to a landing, whereby the need, after a landing has been effected, for additionally manually effect-' ing a driving wedge force behind normally retracted latching dogs is avoided and difficulties in obtaining secure attachment against accidental displacement are eliminated. A further object of the invention is to provide a self locking hanger structure which will remain in place against dislodgment except upon the use of a pulling tool for the application of lifting forces, first to break a releasable connection by which a dog projecting abutment theretofore has been held in dog retraction blocking relation, and then to raise the abutment to dog clearing relation for freeing the previously anchored hanger.

Other objects will become apparent from the accompanying drawing illustrating a preferred embodiment of the invention and wherein Fig. 1 is a view partly in elevation and partly in vertical section showing the improved hanger construction with its parts as positioned prior to being lowered into the well; Figs. 2, 3 and4 are fragmentary views partly in elevation and partly in vertical section and respectively illustrating the latching mechanism with the dogs retracted for downward passage in a landing nipple; with the dogs projected in nipple latching position andwith the dogs retracted for re moval from the nipple; and Fig. 5 is a transverse section on line 5-5 of Fig. l.

In the drawings a' standard nipple 1 for coupling insertion within a tubing string consists of a tubular wall enclosing an inner tubular core Sand mounting one or lmore latch dogs 9 for relative movement both axially and laterally of the housing for outward projection and inward'retraction relative to the housing outside. For convenience of manufacture and assembly, the outer housing 7 is made up of separate parts 10, 11 and 12 screw threaded together in end to end succession.

The lowermost housing part 12 terminates in a reduced diameter tip 13 which is externally screw threaded for mounting thereon an extension tube or a well tool, as, for example, a conventional choke to control fluid flow through the tubing string. Packing rings 14 surround a reduced diameter neck portion of the housing element 11 and are held in place by the co-operating lower housing element 12. They are to make sealing contact with the internal surface of a nipple for insuring against fluid leakage about an installed hanger.

Near its upper end the housing part 10 has an annular enlargement 15 of a diameter to fit within the counterbore 2 of the nipple. The bottom shoulder 16 of the enlargement affords a stop seat for abutment with the nipple landing seat 3 at the. downward limit of hanger travel. Spaced slightly below the stop seat 16, the housing part 10 is of reduced outside diameter to form an annular peripheral groove ,or reduced diameter portion 17 whose opposite ends are defined by an upper shoulder 18 and a lower shoulder 19 conveniently constituted by the upper edge of the housing element 11. Slidably sleeved on the reduced portion 17 is a collar or annular band 20 and a helical coil spring 21. One end of the coil spring bears on the upper shoulder 18 and the other end bears on the uppermargin of the collar 20 and 7 acts to bias the collar downwardly into abutment at its lowermargin with the shoulder 19. The yieldable biasing force or the spring 21 is transmitted to the latching dogs 9 which project and have radial slide movement within windows 22 formed in the sleeve 20 of a size only slightly greater than the dog portions projected therethrough. The axial spacing between theseating shoulder 16 and the windows 22 when the collar abuts the shoulder 19 is related to the axial spacing between the nipple landing seat 3 and the nipple keeper groove 4 so that in the landed position of the tool the latch dogs 9 are aligned with the keeper groove 4.

Inwardly of the slide collar 20, each dog is extended upwardly and downwardly, forming retaining ears '23 for co-operation with the inside face of the collar in limiting the range of outward dog projection. This inward portion of each dog 9 is located within and is of a vertical dimension of about half the length of an axially elongated slot 24 extending through the wall of the housing part It} and is slidable therein against elastic restraint of the coil spring 21. i

In their upper portions the tubular inner core 8 and the tubular housing. part 10 have mating bearing surfaces of cylindrical configuration for a free sliding fit one on the other and below the slidably fitted surfaces, each cylindrical surface is stepped away from the ,other.* 'The reduction in diameter of the core 8 affords a peripherally relieved portion 25 for an axial distance corresponding at least to the axial dimension ofthe inward face of the dog 9 and its extensions '23. Immediately below the re; lieved portion 25, the diameter of the core 8 is enlarged to approximately the diameter of the enlarged internal diameter of the lower portion of the housing part 10 so as to form an annular band enlargement or rib 26 which constitutes a stop abutment against dog retraction when radially aligned with the dogs 9. Below the band or 9' enlargement 26, the wall of the core8 is again of reduced external diameter, providing a peripherally relieved portion 27. Separating the stepped internal diameters of the housing part 10 is a downwardly facing shoulder;,28 which provides a stop limit abutmentfontheupper shoulder 26' of the rib enlargement 26 upon relative slide travel of the core and housing. When the housing and core are held against relative slide travel, as seen in. Fig. l, the axial spacing of the shoulders 28- and 26' approximates. and should be at least as great as the axial length. of the stop. abutment face of the rib enlargement 26.

The upper end of the hollow core 8 has threaded on it a fishing neck adapter 29 which terminates in an enlarged head 30 over which can be snapped any of the conventional pulling tools, as indicated generally at 31 inFig. 4. The bottom of the neck adapter 29 normally is seated against the upper. edge of the upper housing element as a limit stop to relative core travel downwardly in .the housing. This is the initial position of the partsas seen in Fig. l and is releasably maintained as by means of'a shear pin 32 extending through aligned openings formed partly in each the core 8 and the housing element 10. A similar shear pin 33 is fitted to the upper end of the housing part 10 and to a conventional lowering tool 34 when the hanger is ready to be placed in a well.

In. use the hanger assembly secured to a running, or lowering tool 34. on the end of a wire line and with the core and housing releasably coupled by the shear pin 32,v is lowered into the tubing string from the surface and its lower end on reaching the landing nipple will enter the same until the shoulder 16 contacts with the landing seat 3 and stops further descent. In the final increment of downward hanger movement the outwardly projected dogs 9 backed by the rib 26 will come into abutment with the landing seat 3 and temporarily will be held against further descent as permitted by the housing slot 24 and the compressed length of the coil spring 21 while the housing slides in the sleeve or collar 20. Such relative movement carries the abutment rib 26 downwardly below alignment with the stopped dogs 9 and as the rib moves from behind the inner faces of the dogs, the peripherally relieved core portion above therib comes into alignment with the dogs and receives the dogs for their radial retraction and inward slide travel out of bearing on the landing seat 3. The inward relief or radial clearance is such that the outer tip portions of the retracted dogs can slide below the landing seat 3, as is indicated in Fig. 2, for accommodating continued descent of the tool assembly. At or just before the time the housing shoulder 16 finally lands on the nipple seat 3, the inwardly retracted dogs will become aligned with the internal keeper groove 4 so that the dogs are free to move outwardly into the groove and thenslide down in front of the enlarged rib 26 under the resilient force of the coil spring 21 transmitted through the slide collar 20. With the dogs projected from the housing into the annular keeper groove and so maintained against retraction by their inward abutment with the positioning rib 26, the landed hanger will be securedly latched against accidental dislodgment from the nipple, as shown in Fig. 3. As soon as the automatic latching action has been completed, an upward jar force on the running tool 34 resisted by the latched-in housing will shear the pin 33 for removal of the wire line and running tool.

When retrievement of the hanger is desired at any later time, the usual wire line pulling tool 31 is lowered and snapped over the pickup head of the core 8, whereupon an upward jar transmitted through the wire line will shear the pin 32 for releasing the connection between the core '8 and the housing 10. Lift force will now raise the core relative to the latched-in housing until the-upper shoulder 26' of the rib 26 comes into abutn l'entl with the housing shoulder 28, at which time the rib 26- will also be out of radial alignment with the dogs 9- and the lower relieved portion 27 of' the core willprovide-clearancefor inward retraction of the dogs out of the keeper notch 4 and for travel upwardly as the assembly moves clear of the nipple. To assist inward and outward camming of the dogs in response to relative movement between the parts, the corners of the dogs are preferably beveled according to conventional practices as are their co-operating-camming surfaces on the rib 26 and the nipple.

From the foregoing, it will be apparent that there has been provided an improved hanger which can be readily installed in a landing nipple with a self latching action for eliminating skilled manipulation as heretofore required for forcibly effecting an outward dog wedging after a landing has been made and which latched-in assembly likewise canbe easily removed when occasion arises. While only a single embodiment has been de scribed, it is to be understood that modifications can be made such as come within the scope of the appended claims.

What is claimed is:

1. In a well tool, a tubular housing having a travel stop seat, a slide sleeve mounted on the housing for movement axially thereof, spring means bearing downwardly on said sleeve and yieldably resisting upward slide travel thereof, a fixed stop on the housing engageable by the sleeve at its lower limit of slide travel, a retractable-projectable dog radially movably mounted by the sleeve,vinterengageable surfaces on the dog and the sleevedefining the outward limit of dog projection, said housing having an axially elongated slot slidably receiving the inner end of said dog, a central core slidable within the housing, a releasable connection between the housing and said core retaining the core against relative slide movement in the housing, a bearing abutment on said core engageable with the inner end of the dog to maintain the same radially projected from the sleeve when the latter is at its lower travel limit, a radially relieved portion on the core upwardly of said core abutment and radially. aligned with the inner end of the dog when the latter is carried upwardly with the sleeve, said relieved portion providing clearance for inward dog retraction and another relieved portion on the core downwardly of said bearing abutment and movable with the core upon release of said connection and into radial alignment with the inner end of the dog and thereby providing clearance for inward dog retraction.

2. A well tool according to claim 1 in which said housing has a running tool engageable head and said dog in its projected position during a running-in operation being engageable with a landing nipple to stop descent of said sleeve with the housing until said dog becomes radially, aligned with and retracts into said upper relieved portion of the core and said core having a pulling tool engageable head through which upward force can be applied for releasing said connection and raising the downward relieved portion of the core into radial alignment with the dog.

3. In a well tool, a hollow housing having a locating ,stop abutment and an upper bore portion of small diameter anda lower bore portion of large diameter, a downwardly facing shoulder separating said bore portions, 21 core slidable in the housing and having axially spaced small and large diameter portions respectively received in said bore portions and having an upwardly facing shoulder at the. junction of said portions of the core for stop abutment with the housing shoulder, a releasable connection joining the core and housing against relative slide travel in a position in which said shoulders are normally axially spaced apart, a sleeve having a dog receiving window and being slidable on the housing between axially spaced apart positions in the lower of which said window is radially aligned with the large diameter portion of said core and in the upper of which positions said window is radially aligned with the small diameter portion of'the core above its shoulder, elastic means positioned on the housing in downwardly biasing -engagement on the slidable sleeve; said housinghaving an axially elongated window therein aligned at all times with the window of the slidable sleeve, a radially relieved portion on the core positioned below its large diameter portion, said large diameter portion being of an axial length less than the distance between the normally spaced apart shoulders and being out of alignment with said window in said sleeve when the sleeve is in its lower position in the elongated window ofsaid housing when the sleeve slides on the housing, said dog having a sleeve engageable stop abutment against outwardly projected separation from the. sleeve and being laterally positionable by the sleeve in co-operation with said core portions, said large diameter core portion, when aligned with the window in said sleeve, abutting and maintaining the dog projected radially outwardly of the housing and the other two core portions, when either is aligned with the window in said sleeve, afiording inward clearance for radial retraction of the dog.

4. In combination with a well tubing nipple having a tool landing seat and a keeper groove below the seat, a retrievable well tool hanger for removable reception within said nipple, said hanger comprising a hollow housing having an axially elongated slotin the side wall thereof and having a stepped diameter bore presenting a downward facing stop abutment above said slot, a core slidable in the housing between upper and lower limits, a releasable connection between the housing and core holding the latter at its lower limit, a radial enlargement of the core engageable with said abutment to establish the upper limit of core slide travel when said connection is released, said enlargement being of an axial length less than the length of said slot and being positioned in radial alignment with the lower part of the slot to provide clearance inwardly of the upper part of the slot when said core is at its lower limit and being positioned in radial alignment with the upper part of the slot to provide clearance inwardly of the lower part of the slot when said core is at its upper limit, a lowering tool engageable formation on the housing for releasable suspension coupling with a lowering tool, an external stop shoulder on the housing engageable with said landing seat when the slot is radially aligned with said keeper groove, a dog having a retaining portion thereon, dog retainer means on the housing engageable with the dog and the retaining portion thereof to hold the dog against separation from the retainer means and slidably locating the dog for axial travel within the slot between lower and upper positions, said dog in its lower position when the core is at its upper limit being retractable from the keeper groove into the clearance below said enlargement and said dog when the core is at its lower limit being engageable with said enlargement to maintain the dog projected at its lower position and being out of engagement with said enlargement and radially aligned with the clearance thereabove for dog retraction at its upper position, elastic force exerting means interposed between the housing and the dog and active to bias said dog downwardly in its slot and a pulling tool engageable formation at the upper end of the core through which force can be transmitted first to release said connection and then to lift the hanger from the nipple.

5. A well tool hanger for retrievable locked mounting in a tubing string nipple and comprising a pulling tool engageable core having a dog projectable abutment between the core and housing for holding'the samewith said stop surfaces axially spaced apart a distance greater than the length of said abutment, said housing having an axially elongated slot through the side thereof in radially overlapping relation with both said abutment and the peripherally relieved portion thereabove when said releasable connection is effective and which slot is in radially overlapping relation with the peripherally relieved portion below said abutment when said stop surfaces are interengaged, a dog having a retaining portion thereon, dog retainer means carried by the housing and engageable by said dog and the retaining portion thereof and holding the dog in assembly relation with the housing, said dog being axially slidable in said elongated slot and radially shiftable therein for alignment with and inward retraction into said relieved portions and for alignment with and outward projection by said abutment and yieldable means on the housing having force transmitting relation with and biasing said dog downwardly in said elongated slot.

6. A well tool hanger for retrievable locked mounting in a tubing string nipple and comprising a pulling tool engageable core having a peripheral dog projecting abutment and inwardly relieved dog receiving clearances above and below said abutment, a running tool engageable housing slidably enclosing said core and having an internal shoulder engageable by said abutment at the upper limit of slide travel ofthe core in the housing, an external nipple seating surface on the housing, a releasable connection joining the housing and the core and holding the same with said shoulder and abutment axially spaced apart, said housing having an annular peripheral groove whose top and bottom margins form lateral shoulders and having an axially elongated slot through the housing wall at'said groove and of a length to overlap at one end with the inward clearance above said abutment when said clearance is efiective and to overlap at the other end with the inward clearance below said abutment when the latter is engaged with said internal shoulder, a slide collar fitted in said groove for travel to and from the bottom groove shoulder, a coil spring also fitted to said groove and bearing upwardly on the top groove shoulder and bearing downwardly on said slide collar to yieldably bias the same downwardly, a nipple engageable dog held by said sleeve and radially projectable and retractable relative thereto and axially slidably fitted in said elongated slot for co-operation with said abutment in the projection of the dog and with the inward clearance on either side of said abutment in the retraction of said dog, and co-operating seating faces on the dog and said sleeve engageable with one another in holding the dog against separation from the sleeve.

7. In a well tool, a pulling tool engageable core having a dog projecting abutment and inwardly relieved dog receiving clearances above and below said abutment, a running tool engageable housing slidably enclosing said core and having an external stop surface thereon, a releasable connection joining the housing and core and holding the core against upward slide travel in the housing co-operating shoulders on the core and housing engageable as a limit stop to upward core slide travel relative to the housing, a radially and axially shiftable dog and dog retaining and biasing means connecting the dog and housing against separation and acting on the dog to yieldably resist its axial movement upwardly relative to,

the housing from a position aligned with and projected radially outwardly by said abutment, said dog upon relative axial movement between the dog and the housing when the latter is releasably connected with the core being shiftable out of alignment with the abutment and radially retractable into the dog receiving clearance above said abutment and said core being slidable upwardly in the housing upon release of said connection to a position in which said abutment is out of alignment with the do;

for radial retraction of the dog into the clearance below said abutment;

8. In a retrievable well tool: to bepassed through a well: pipe, 8. pair oftubular membershaving'slidably sleeved interfitment, interengageable means on saidmernbets defining alimited range. of relative slide travel therebetween, a releasable connection joining said members initially in fixed position against relative slide travel, the wall surface of one member'which faces the wall sur- -face of the other member having axially successive zones, -one of which is of relatively reduced diameter and another of which is of relatively increased diameter, a laterally projectable latch dog, retaining means slidably holding said latch dog on the other member for movement relative thereto, both axially and laterally thereof, and for slide bearing engageament with said zones respectively during relative axial movement for control of .dog lateral movement and spring means carried by said other member in elastioforce, transmittingrelation to the dog and aetive while. saidv members are fixedly held by said releasable connection to bias the dog axially to a normal position in lateral bearing engagement with: the zone of increased diameter and to yield for relative :axial dogtravel into axial bearing engagement with; the other zone and active upon relative slide travel of said members to one limit after release of their connection, to bias the dog; axially in position free of lateral bearing engagement with both zones.

References Cited in the file of this patent UNITED STATES PATENTS

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