US3283824A

US3283824A - Hydraulically set well anchors

Info

Publication number: US3283824A
Application number: US315909A
Authority: US
Inventors: Hoffman Jack; Denzal W Van Winkle
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1963-10-14
Filing date: 1963-10-14
Publication date: 1966-11-08
Anticipated expiration: 1983-11-08

Description

NOV 8, 1966 I J. HOFFMAN ETAL 3,283,824

HYDRAULICALLY SET WELL ANCHORS Filed Oct. 14, 1963 .'3 Sheets-Sheet l EG@ fr 26' 3 Sheets-Sheet 2 INVENTORS. clqcz HOFF/wmv DE/vznL I/VI L/wv PWA/LE 5y MW rroQ/VEYS NOV- 8, 1966 J HoFFMAN ETAL HYDRAULICALLY SET WELL ANCHORS Filed oct. 14, 196s Nov. 8, 1966 J. HOFFMAN ETAL. 3,283,824

HYDRAULICALLY SET WELL ANCHORS 5 Sheets-Sheet 5 INVENTORS. ziale/6 HOFFMQN' DEA/2m. PV: Vw PWN/LE Filed Oct. 14, 1963 5y 776% @j www TToQ/VEYS.

United States Patent O 3,283,824 HYDRAUMCALLY SET WELL ANCHRS Jack Hoffman, Jackson, Miss., and Denzal W. Van Winkle, La Mirada, Calif., assignors to Baker Oil Tools, Inc., Los Angeles, Calif., a corporation of California Filed Uct. 14, 1963, Ser. No. 315,909 Claims. (Cl. 16d-212) The present invention relates to subsurface well bore equipment, and more particularly to anchors adapted to be run and set in well casing and similar conduit strings disposed in well bores.

Certain types of subsurface well bore apparatus embody gripping elements that are expanded outwardly hydraulically against the wall of a surrounding well conduit to anchor the apparatus thereto. During lowering of the apparatus through the iiuid in the well conduit, pressure diiierentials can be developed of suliicient extent as to effect expansion of the gripping elements against the conduit wall. The same undesirable action might be produced during elevation of the apparatus through the luid in the well conduit. As a result, the teeth of the gripping elements or members slide along the well conduit wall, resulting in their dulling and inability to embed themselves subsequently in the conduit wall for the purpose of electively anchoring the apparatus to the well conduit. Heretofore, resistance to outward expansion of certain types of hydraulically expandable grippingV elements has been provided by retracting springs. Such springs, however, can only resist compartively low pressure differentials. Despite their presence, dulling of the gripping elements still occurs. The spring have the disadvantage of reducing the hydraulic pressure available for holding the gripping members anchored against the conduit wall. In addition, the provision of the springs imposes design limitations on the apparatus, restricting the range of expansion of the gripping members and the range of conduit sizes in which the same size apparatus can be used etectively.

An object of the persent invention is to provide hydraulically set subsurface well apparatus having gripping elements held positively in retracted position during lowering or elevating of the apparatus through fluid in the well bore, or during both lowering and elevating of the apparatus in the well bore.

Another object of the invention is to provide a hydraulically set well apparatus having gripping elements held positively in retracted position during longitudinal movement of the apparatus in the well bore, the elements eing releasable for outward expansion, then being reshiftable to retracted position, and again positively retained in such position.

A further object of the invention is to provide a hydraulically set well apparatus adapted to be lowered in a well bore on a running-in string and having gripping elements held positively in retracted position by a holding device, the holding device being positively releasable by a longitudinal force imposed on the running-in string, and the gripping elements being positively retractable from their outwardly expanded position by a longitudinal force transmitted through the running-in string to the holding device and gripping elements.

An additional object of the invention is to provide a hydraulically set well apparatus having gripping elements held positively in retracted position by a holding device which is releasable when the gripping elements are to be expanded hydraulically, and which automatically retracts the gripping elements and retains them in retracted position upon release of the hydraulic expansion force.

Yet another object of the invention is to provide a well apparatus having gripping elements expandable outwardly by lluid pressure, in which the lluid pressure is fully utilized to urge the gripping elements against the confining conduit string in the well bore, inasmuch as the apparatus does not embody spring retracting devices, or the like, acting upon the gripping elements.

Still a further object of the invention `is to provide a well apparatus having gripping elements expandable outwardly by tluid pressure againt the wall of a well conduit, the elements having a comparatively large range of expansion, enabling the same size apparatus to be set in a greater range of conduit sizes.

Another object of the invention is to provide a hydraulically set well apparatus embodying button or pispiston type of gripping elements adapted to be positively held in retracted position by a device which also serves to maintain the elements properly oriente-d in the body of the apparatus.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the persent specication. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best dened by the appended claims,

Referring to the drawings:

FIGURES la and lb together constitute a combined side elevational view and longitudinal section through a well packer and anchor apparatus embodying the invention, with the parts in retracted position, FlG. 1b being a lower continuation of FIG. 1a;

FIGS. 2a and 2b are views corresponding to FIGS. la and 1b, illustrating the well packer anchored in packedolf condition againstthe well casing, FIG. 2b being a lower continuation of FIG. 2a;

FIG. 3 is a front Velevational view, on 'an enlarged scale, of a button or piston anchor portion of the apparatus, with the retaining device in an intermediate position;

FIG. 4 is a longitudinal section taken along the line 4-4 on FIG. 3;

FIG. .5 is a cross-section taken along the line 5-5 on FIG. 4;

FIG. 6 is an exploded view of a plurality of piston type gripping elements and a retaining and orienting bar used in connection therewith.

The apparatus A illustrated in the drawings is a setdown type of well packer 10 combined with an upper anchor portion 11, the apparatus bei-ng adapted to be lowered and elevated through a string of well casing B, or similar conduit string7 on a tubular string C, such as a string of tubing, extending to the top of the well bore. Fluid under pressure is adapted to be pumped downwardly through the tubular string and the apparatus, and suc-h fluid under pressure will hydraulically actua-te the anchor portion 11 of the apparatus to hold it set against the wall of the well casing.

The apparatus includes a central main body or mandrel 12 |having a passage 13 therethrough, the upper portion of the body being threadedly secured to a body sub 14 having a threaded box 15 for attaching the latter to the lower pin end 16 of the tubular string C. The mandrel extends downwardly through Ithe entire extent of the apparatus, its main body portion being threaded into the upper end of a lower body sub 17, which ,may constitute the terminal porti-on of the apparatus, or, which may, if desired, be threadedly secured -to a lower section 18 of tubing or a lower tool.

The upper portion 11 of the apparatus includes an anchor body 19 surrounding the mandrel 12 and relatively slidable with respect thereto. This anchor body has a plurality of circumferentially spaced cylindrical bores 20 therethrough, each of which contains -a piston gripping element 21 slidable radially therein. The cylindrical bores open to the interior of the anchor body 19 and also to the exterior thereof. The piston gripping elements have external wickers or teeth 22 facing in an upper direction to anchor the apparatus to the well casing against upward movement.therewithin As shown in the drawings, a plurality of cylinders 20 and gripping elements 21 are provided in longitudinal alignment with one another, to increase the number of elements 21 available for anchoring the apparatus in the well casing. Of course, the anchor portion of the apparatus could include only a single set of circumferentially spaced gripping elements and cylinders, instead of the plurality of longitudinally spaced sets disclosed.

The piston gripping elements are expanded outwardly whenever fluid pressure differential is present interiorly of the anchor body 19. In the specific tool illustrated, such fluid pressure is derived from the exterior of the tool below the anchor portion of the apparatus, which pressure can pass through an annular by-pass 23 between the anchor body 19 and the .periphery of the mandrel 12, the inner portions of the cylinders opening into such annular by-pass. When by-passing of the fluid is prevented, a pressure diierential of the fluid within the by-pass 23 can be built up, such pressure acting through the fluid in the cylinders 20 upon the hydraulically actuatable pistons 21 to urge the latter outwardly `and force their teeth 22 into anchoring engagement wit-h the wall of the well casing. Leakage of fluid along each piston is prevented by a suitable piston ring 2li, or side seal ring, on the piston slidably sealing against the wall of its companion cylinder 20.

The inner mandrel 12 is shiftable longitudinally with respect to the anchor body 19 to open and close the annular by-pass 23. A valve seal ring 25 is molded to a ring 26 secured to the upper `mandrel sub 14 by an encompassing upper latch sleeve 27 secured to the sub. The seal ring is adapted to move downwardly into engagement with a valve head 28 at the upper portion of an anchor body extension 29, projecting upwardly from and secured to the -main portion of the anchor body 19 containing the cylinders 21B and piston gripping elements 21. The anchor body extension 29 is spaced laterally from the periphery of the mandrel to form a :por-tion of the annular by-pass 23, which opens through the upper `end of the valve head 28 when the valve seal 25 is disposed thereabove, as disclosed in FIG. 1a.

When the mandrel 12 is shifted downwardly relative to the anchor body 19, its seal ring 25 is moved downwardly into engagement with the valve seat or head 28 to close the upper end of the by-pass 23. This enables the fluid pressure below the tool to be increased, passing upwardly through the by-pass to the cylinders 2l) for the purpose of expanding the gripping elements 21 outwardly into anchoring engagement with the wall of the well casing B.

In the specific tool illustrated, the upper anchoring portion 11 of the apparatus is secured to the downwardly anchoring por-tion 10 of the apparatus, which also includes a packing structure 30 for effecting a seal against the wall of the well casi-ng. The lower portion 31 of the anchor body 19 constitutes an upper abutment for the packing structure. This packing structure may include a connector sleeve 32, the upper end of which is threadedly attached to the lower portion 31 of the packer body, the sleeve being slidable relative to the `mandrel 12 and extending through an initially retracted packing eleme-nt 33 of the structure, which may be of any suitable type. As shown, the packing structure includes a rubber or rubber-like packing sleeve engaging the lower end 31 of the anchor body and a gauge ring 34 threadedly secured thereto to provide the proper clearance with the adjacent wall of the well casing B. The packing eleme-nt surrounds the connector sleeve 32, its lower end engaging a lower abutment 35 th-readedly attached to a lower expander 36. This lower abutment 35 has an inwardly directed ange 3-7 adapted to contact an outwardly extending ila-nge 38 at the lower end of t'he connector sleeve 32. When the

upper abutment

31, 34 is moved toward the lower abutment 35, the packing ymember 33 is shortened and expanded outwardly into sealing engagement with the wall of the well casing, as well as again-st the connector sleeve 32, which is disposed in spaced relation to the periphery of the mandrel 12 to provide a portion of the fluid by-pass 23 of the apparatus. When the

upper abutment

31, 34 moves toward the lower abutment 35, the lower end of the connector sleeve can shift downwardly in an annular space 39 between the expander 36 and the periphery of the mandrel 12.

The lower portion of the expander has an ex-ternal conical or expander surface 40 tapering in a downward and inward direction and adapted to coact with companion inner tapered surfaces 41 on the anchor portions 42 of rocking types of slips 43 disposed in annular grooves 44 in a sli-p ring 45 slidable relative to the mandrel or body 12. Each slip 43 has a lower drag portion 46 urged outwardly into frictional engagement with the wal-l of the casing by a plurality of helical compression springs 47 mounted in each groove and bearing against the base of the latter and against the drag portions of the slips. The slips are so designed that the springs 47 force the drag lportions 46 into full yfrictional engagement with the wall of the well casing B, rocking the anchor portions 42 inwardly away from the wall of the well casi-ng, the downwardly facing wickers or tee-th 48 on the anchor portions being prevented trom contacting the adjacent casing wall. However, when the expander 36 rnoves downwardly relative to the slips 43, its outer tapered surface 40 engages lthe anchor portions 42 and rocks them outwardly into engagement with lthe casing wall, the rocking action, at rst, occurring about the upper part 49 of the drag portion 46 of each slip.

The slips 43 are movable jointly downwardly in the casing by a retainer ring 5t) mounted in external grooves 51 in the slips between their drag and

anchor portions

46, 42, the upper end of this retainer ring being engaged by an 4outwardly directed lange 52 at the upper end of the slip ring 45. Downward movement of the slip ring will cause its lflange 52 to engage :the ring 50, the latter engaging the lower sides of the slip grooves 51 so as to ypull all of the slips 43 downwardly in the well casing. Joint upward movement of the slips is provided by a stop ring 53 engaging their lower ends, ythis stop ring being suitably secured to the slip ring, as by means of longitudinally extending screws (not shown). When the apparatus i-s out of the well casing, 4outward movement of the slips 43 is limited by the retainer ring Sli and also by the lower terminals 54 of the slips engaging a stop rim 55 projecting upwardly from land integral with the stop ring 53.

The lower expander 36 is shiftable downwardly relative t-o the lower slips 43 to ancho-r them against the well `casing and the

upper abutment

31, 34 is movable toward the lower abutment 35 to expand the packing 33 against the well casing in response to downward movement of the mandrel 12 relative to the parts surrounding it. Such relative downward movement also closes the annular by-pass passage 23 of the apparatus, which extends from a location below the packing structure 30, as from side ports 56 provided through the expander into the space 39, to the valve head 28 of the anchor body extension 29. The ability tof the body or mandrel to move downwardly to effect setting of the apparatus is governed by a control unit 57 of any suitable type, such as a pin and J-slot mechanism at the lower portion of the apparatus. As shown, the control unit includes a sleeve 58 suitably secured, as by welding, to the stop ring 53, this sleeve having a I -slot 59 therein, including a horizontal lock portion 6i) and a longitudinal release portion 61. A radi-al pin 62 extends laterally from the lower `sub 17 and is adapted to move in the J-slot 59. When lthe mandrel 12 is in its upper position with the pin 62 in the horizontal por-tion 60 of the slot, downward movement of :the mandrel carries all of the part-s surrounding it downward-ly with it. Downward movement of the slip .assembly 42-53 with the mandrel is transmitted to the expander 36 through longitudinal limit pins or screws 65 threaded in the lower exp-ander 36 and received within bores 63 in the sl-ip ring 45, the heads d4 of the screws engaging the upper ends of :the bores or sockets 63. A-s `a result of this arrangement, downward motion of the slip ring 45 is transmitted through the screws 65 to the lower expander. However, upon downward movement of the llower exp-ander 36, the screws 65 slide longitudinally in the slip ring 45, enabling the expander to move behind the anchor portions 42 of the slips and expand them outwardly against the wall of the Well casing. The downward movement of the expa-nder 36 is transmitted through Ithe gauge ring 35 to 4the connector sleeve 32 and through the latter to the ancho-r body 19. Thus, the Ianchor portion 11 of the apparatus is shifted downwardly with the mandrel 12, the upper valve seal remaining spaced above the valve head 28, the by-pass 23 being in its open condition.

When It-he mandrel 12 is turned by the tubular string C to shift the lock pin 62 from the horizont-al portion 60 of the -control slot 59 into alignment with Ithe longitudinal portion 61 of the slot, the mandrel can move downwardly rela-'tive to the parts surrounding it, since downward movement of such latter pa-rts is -resisted by the frictional engagement of the drag portions 46 of the slips `against the wal-l of the well casing. Such downward movement of the mandrel brings its va-lve seal 25 into engagement with the valve head 28 to close 4the upper end of the fluid -by-pass passage 23, the entire anchor portion 11 of the apparatus shifting downwardly .to carry the packing assembly and expander 36 downwardly with it, urging the expander downwardly within the slips 43 and shifting the anchor portions 42 of the latter outwardly to embed :their teeth 48 -in the wall of the well casing. Continued downward movement of the tubular string C and `mandrel 12 wil-l shift the anchor body 19 downwardly, urging the uper abutment 31, r34 toward the lower abutment and shortening the packing element 33, expanding the latter radially outwardly `again-st the wall of :the well casing B.

Fluid under pressure can now be pumped down through the apparatus, such ui-d pressure passing out through the lo-wer end 18 of the tool into the casing and then upwardly through the by-pass ports 56 into the bypass 23 and to the interior of the ycylinders 20 for the purpose of urging the piston gripping elements 21 outwardly int-o gripping 'engagement with :the wall of the well casing. The piston gripping elements lcan then prevent upward 'movement of the apparatus A in the well casing under the action of the duid pressure, downward movement of the apparatus being prevented by the lower slips 43 and com* pa'nion lower expander 36.

If it is desired to release the .apparatus from the well casing, it is only necessary -to elevate the tubular string C and mandrel 12, which will elevate the valve seal 25 above its companion seat 28, opening the by-pass 23 and allowing the pressure above and below the apparatus to equalize. The mandrel is shifted upwardly runtil ting/ers 79 thereon engage a downwardly facing shoulder 71 on the anchor body extension 29 :to pull the anchor body 19 upwardly and the upper Iabutment 311, 34 awray from the lower abutment 35, all-owing the packing element 33 to inherently retract from the well casing. 'Ilhe flange 33 on the connector sleeve engages the -lower abutment or gauge ring 35 to pul-l the expander 36 upwardly from the slips 43, allowing the springs 47 to reengage the drag portions 46 of the latter fully with the well .casing and rock their anchor portions 42 inwardly from engagement with the well easing. Upward movement of the expander 36 is transmitted through the screws 62to the slip ring 45 to cause the entire slip assembly to move upwardly in the casing. The mandrel can be shifted upwardly, if desired, to relocate the lock pin `62 in alignment with the horizontal portion 60 of the slot, the mandrel then being turned to reshift the pin in such portion. The apparatus can then, if desired, lbe shifted downward-ly in the well casing, the parts remaining in their retracted positions.

During lowering of the apparatus, and particularly the anchor portion 11 thereof, in the well casing, a iluid pressure differential might be developed in the by-pass 23, which iiuid pressure acts on the piston gripping elements 21 and urges them outwardly against the Wall of the well casing, resulting in sliding of their teeth 22 along the casing wall and their dulling. As a result, the gripping elements or members would be less effective, and may, in fact, be ineffective for anchoring the apparatus against upward movement in the well casing. The uid pressure differential would become more pronounced in the event the tool were lowered in the well casing with the upper end of the by-pass 23 closed. Similarly, with the upper end of the bypass open, elevation of the apparatus through the uid in the well casing could develop a pressure differential in the fluid in the bypass, which would also urge the piston gripping elements 21 outwardly against the wall of the well casing, resulting in dulling of their teeth 22. In the hydraulic anchor illustrated in the drawings, the gripping elements 21 are prevented from being shifted by fluid pressure outwardly against theV wall of the well casing, except when outward expansion of such elements against the casing wall is desired.

As illustrated in the drawings, a retaining housing or sleeve 74 is disposed around the anchor body, its upper portion 75 being circumferentially continuous and providing an enclosure for a helical compression retracting spring 76 disposed around the body extension 29. The lower end of the spring acts against the upper end of the anchor body 19 and its upper end against an inwardly directed flange 7'7 of the retaining sleeve, tending to urge the sleeve '74 in an upward direction and into engagement with an upper ange 75 of the anchor body extension. integral with the circumferentially continuous upper portion 75 of the retaining sleeve are longitudinally extending retaining and orenting members or bars 79, there being one bar for each longitudinally aligned set of gripping elements 21. Each bar extends through a companion longitudinal groove 80 in the anchor body and through the cylinders 2t), the sides 81 of the groove being tapered or convergent in a lateral outward direction, the bar having companion tapered sides 82 engageable with such inner tapered sides of the groove to prevent outward deiiection or movement of the bar with respect to the anchor body 19. Lateral inward movement of the bar cannot occur in view of its engagement with the base 83 of the longitudinal body groove.

Each bar 79 extends across longitudinal slots or grooves S4- in the outer portion of a longitudinally aligned set of gripping elements 21, the sides of the bar being engaged by the side walls 85 of the gripping element grooves so as to maintain the gripping elements properly oriented within their cylinders 20, with their wickers or teeth 22 facing in an upward direction for appropriate embedding in the wall of the well casing B. In addition to orienting the gripping elements 21, the bars 79 can selectively retain the gripping elements in their inward or retracted positions within their respective cylinders, or permit their outward expansion under the action of fluid pressure within the by-pass 23 and inner portions of the cylinders 2t). As shown, each gripping member has a retaining, cam or detent portion 86 projecting outwardly from the base of its groove 84, the lower surface 87 of the detent being inclined in an upward and outward direction. Each bar has a release notch or opening 88 in a side thereof into which the detent 36 is adapted to project, the bar at the lower end of each notch having a cam or retracting surface 89 inclined in an upward and outward direction for coaction with the inclined detent surface 87. The portion of the bar below each opening 8S is adapted to engage the detent 36 for the purpose of holding the gripping element 21 fully in its retracted position, and to positively preclude its outward expansion under the action of fluid pressure.

When the retaining sleeve 74- is in its upper position on the anchor body 19, as disclosed in FIG. la, the retaining or retracting bars 79 are disposed across the detents 86 and will positively prevent the gripping elements 21 from shifting outwardly. The development of high pressure differentials within the by-pass 23 will be incapable of shifting the gripping elements outwardly of their cylinders 20, since their detent portions 86 engage the retaining bars, the bars themselves engaging the tapered sides 81 of the longitudinal body grooves 8i).

To permit outward expansion of the gripping elements, the retaining sleeve '74 is moved downwardly along the body 19, which correspondingly shifts the retaining bars 79 downwardly to a position in which the release notches or openings 88 are aligned with the detents 86 of the gripping elements, the bars no longer being capable of retaining the gripping elements 21 in their retracted positions. Consequently, the development of fluid pressure in the by-pass 23 will enable such pressure to act freely on the gripping elements and shift them in a lateral outward direction within their cylinders 2th into gripping engagement with the wall of the well casing b. Such outward shifting is free from restraint by any portions of the apparatus.

Following the equalizing of the pressure internally and externally of the tool, the retaining sleeve 74 can be shifted upwardly along the body 19, which will cause the cam portions 39 of the bars 79 to engage the inclined surfaces 87 of the detents 86 and force the gripping elements 21 radially inwardly of their cylinders 20, the bars sliding fully over the detents 86 back to the position illustrated in FIG. la, in which they will again positively prevent shifting of the gripping elements in a lateral outward direction within their cylinders.

As disclosed in the drawings, the retaining sleeve '74 is normally held in its upper position holding the gripping elements 21 inwardly of the anchor body 19 by the helical spring 7d. Downward shifting of the retaining sleeve 74, for the purpose of releasing the gripping elements 21 for outward expansion hydraulically, is accomplished by the shifting and latch sleeve 27 threadedly secured to the upper mandrel sub 14, and which is also used to hold the valve seal 25 in place, as above described. The shiftable latch sleeve 27 is of the collet type having depending spring-like arms 91 terminating in inwardly directed lingers 92 having lower surfaces 93 inclined in a downward and outward direction and adapted to engage a companion inclined or tapered surface 94 at the upper end of the retaining sleeve 74. When the control unit 57 of the apparatus is released by turning the mandrel 12 to Shift the lock pin 62 into alignment with the longitudinal portion 61 of the I-slot 59, the mandrel or body is shifted downwardly within the parts surrounding it, the shifting latch sleeve 27 moving down with the mandrel and its fingers 92 engaging the tapered portion 94 of a retaining sleeve flange 95. The exertion of sufiicient downward force on the shifting sleeve will cause the fingers 92 to expand outwardly and slide over the flange 95, then snapping into a peripheral groove 96 in the retaining sleeve therebelow, the downward motion of the latch sleeve 27 and the mandrel 12 then causing the retaining sleeve 74 to shift downwardly against the force of the helical spring 76 to correspondingly move the retaining bars 79 downwardly along the body of the tool and the gripping elements to place the notches or openings 88 of the bars in alignment with the detent portions 86 of the gripping elements. Following such alignment of the detent portions with the openings, which frees the gripping elements 21 for outward expansion, the valve seal 25 moves downwardly into sealing engagement with its companion valve seat 28 to close the upper end of the by-pass 23.

Continued downward movement of the mandrel 12 will then cause the lower expander 36 to shift the slips 43 into engagement with the wall of the well casing B and will also shorten the packing element 33 and expand it against the wall of the well casing. Fluid under pressure can now be pumped downwardly through the tubular string C and mandrel 12, such fluid pressure passing around the lower portion of the apparatus and entering the by-pass 23 through the expander ports 56, acting on the inner portions of the gripping elements 21 to urge the latter outwardly and embed their teeth 22 against the wall of the well casing.

When the apparatus A is to be released from the well casing, the tubular string C and mandrel 12 are elevated in the manner described above in connection with release of the lower packer portion 10 of the apparatus, the valve seal 25 moving from its seat 2 to equalize the pressure above and below the apparatus, the ngers 92 on the latch sleeve engagingv the flange and positively shifting the retaining sleeve '74 upwardly to `cause the cam elements 89 on the bars to engage the inclined faces S7 of the detents 86 and shift the gripping elements 21 positively inwardly to their retracted positions, the bars then sliding across the detent portions 86 to positively retain the gripping elements in retracted position. Continued elevation of the mandrel effects elevation of the anchor body 19, retraction of the packing element 33 and elevation of the expander 36 with respect to the lower slips 43, allowing the latter to reshift to their retracted position. The apparatus A. can now be elevated in the well casing B and removed therefrom at the top of the well bore, if desired. During such elevation through the iuid in the well casing, any pressure differential that might tend to develop in the open by-pass 23 as a result of such movement will be incapable of inadvertently shifting the piston gripping elements 21 into engagement with the well casing, since they are positively locked in retracted position by the retaining and retracting bars 79.

By virtue of the apparatus specifically illustrated and described, the gripping elements 21 can be positively retracted by the taking of a direct pull on the tubular string C. The gripping elements can be released to permit their hydraulic outward expansion by taking a direct push on the tubular string C, which is transmitted to the retaining sleeve 74 to insure its downward shifting to a released position. In the absence of the latch device snapping over the upper flange 95 of the retaining sleeve, but merely engaging its upper end to shift the sleeve downwardly to a gripping element releasing position, the subsequent elevation of the tubular string C and mandrel 12 to remove the valve seal 25 from its companion seat 28 will allow the pressure to equalize internally and externally of the cylinders 20 and across the gripping elements 21, which will permit the helical retracting spring 76 to elevate the retaining sleeve 74 and reshift the gripping elements 21 to their inward positions within the cylinders, the bars 79 then shifting upwardly fully over the detent portions 86 of the gripping elements to positively hold and lock the latter in their inward positions.

It is thus apparent that an apparatus has been provided in which the hydraulically actuable gripping elements are prevented from being shifted outwardly during lowering of the apparatus through the fluid in the well casing, as well as during elevation of the apparatus through the uid in the well casing. The gripping elements are positively locked in their retracted positions by the retaining mechanism, which also functions to orient the gripping elements properly so that their teeth 22 always face in the appropriate direction for anchoring engagement with the wall of the well casing. Once the retaining sleeve 74 has been shifted to a released position, there are no elements interfering with hydraulic expansion of the gripping elements against the wall of the well casing. Heretoiore, retracting springs were used to resist expansion of the gripping elements and to return the gripping elements to retracted position. The force of such springs had to be overcome by the hydraulic pressure so that a lesser total hydraulic force was available for holding the gripping elements anchored against the wall of the well casing. The absence of restraining springs, and the like, enables the full hydraulic pressure to be available for anchoring the gripping elements against the wall of the well casing. The absence of the springs also enables gripping elements to be provided that have a larger radial extent of movement, since there is no interference by the springs. This permits the use of the same size of equipment for anchoring purposes in a wider range of casings of diering internal diameters.

We claim:

l. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior -of said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; retaining `means engaging said gripping members for holding said gripping members in retracted position in said bores, said retaining means being movable longitudinally of said body from holding engagement with said gripping members; and means for shifting said retaining means in a direction longitudinally of said body from holding relation to said gripping members to permit their outward expansion.

2. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; retaining means engaging said gripping members for holding said gripping members in retracted position in said bores; and means for shifting said retaining means from holding relation to said gripping members to permit their outward expansion; said retaining means embodying instrumentalities engageable with said gripping members for moving said gripping members from expanded position to retracted position.

3. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body; normally retracted casing gripping members on said body for anchoring said body in the well casing; hydraulically operable means for expanding said gripping members into engagement with the well casing; retaining means engaging said gripping members for holding said gripping members in retracted position on said body and to prevent their outward expansion by said hydraulically operable means, said retaining means being movable longitudinally of said body from holding engagement with said gripping members; and means for shifting said retaining means longitudinally relative to said body from holding relation to said gripping members to permit outward expansion of said gripping members.

4. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body; normally retracted casing gripping members on said body for anchoring said body in the well casing; hydraulically operable means for expanding said gripping members into engagement with the well casing; retaining means engaging said gripping members for holding said gripping members in retracted position on said body and to prevent their outward expansion by said hydraulically operable means; and means for shifting said retaining means relative to said body from holding relation to said gripping members to permit outward expansion of said gripping members; said retaining means embodying instrumentalities engageable with said gripping members for moving said gripping members from expanded position to retracted position in response to movement of said retaining means relative to said body.

5. in apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to iiuid pressure Within said body and bones; a mandrel movable within said body; retaining means engaging said gripping members for holding said gripping members in retract-ed position in said bores; and means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit outward expansion of said gripping members.

6. ln apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; a mandrel movable within said body; retaining means engaging said gripping members for holding said gripping members in retracted position in said bores; means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit outward expansion of said gripping members; and means for shifting said retaining means into engagement with said gripping members to retract said gripping merribers from their expanded position.

7. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to uid pressure within said body and bores; a mandrel movable within said body; retaining means engaging said gripping members for holding said gripping members in retracted position in said bores; and 'means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit outward expansion of said gripping members and to shift said retaining means to holding relation to said gripping members to prevent their outward expansion. S. ln apparatus adapted to be anchored in a Well casing'disposed in a well bore: a body; normally retracted casing gripping members on said body for anchoring said body in the well casing; hydraulically operable means for expanding said gripping members into engagement with the well casing; a mandrel movable within said body; retaining means engaging said gripping members for holding said gripping members in retracted position on said body and to prevent their outward expansion by said hydraulically operable means; and means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit their outward expansion. 9. .In apparatus adapted to be anchored in a well casingdisposed in a well bore: a body; nonmally retracted casinggripping members on said body for anchoring said body in the well casing; hydraulically operable means for expanding said gripping members into engagement with the well casing; a mandrel movable within said body; retaining means engaging said gripping members for holding said gripping members in retracted position on said body and to prevent their outward expansion by said hydraulically operable means; means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit their outward expansion; and means for shifting said retaining means into engagement with said gripping members to retract said gripping me-mbers from their expanded position.

lli). In apparatus adapted to be anchored in a well casing disposed in a well bore: a body; normally retracted casing gripping members on said body for anchoring said body in the well casing; hydraulically operable means for expanding said gripping members into engagement with the well casing; a mandrel movable within said body; retaining means engaging said gripping members or holding said gripping members in retracted position on said body and to prevent their outward expansion by said hydraulically operable means; and means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit their outward expansion and to shift said retaining means to holding relation to said gripping members to prevent their outward expansion.

lll. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members insaid bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; a mandrel movable within said body; retaining means engaging said gripping members for holding said gripping members in retracted position in said bores; means operatively connected to said mandrel and movable thereby for shifting said retaining means from holding relation to said gripping members to permit outward expansion of said gripping members; and spring means for returning said retaining means to its holding relation to said gripping members.

12. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; retaining means externally of said body and engaging said gripping members for holding said gripping members in retracted position in said bores; and means for shifting said retaining means longitudinally with respect to said body and gripping members from holding relation to said gripping members to permit their outward expansion.

13. In apparatus adapted to be anchored in a well casing disposed in a well bore: a -body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to iluid press-ure within said body and bores; said mandrel engageable with said body; retaining means extern-ally of said body engaging said gripping mem-bers for holding said gripping members in retracted position in said bores; and means operatively connected to said mandrel and movable thereby for Shiit- -i-ng said retaining means from holding relation to said gripping members to permit their outward expansion.

i. In apparatus adapted to be anchored in a well casin-g disposed in a well bore: a body having a plurality of bores therein opening `to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; said gripping members having longitudinal slots in their outer portions; retaining means externally or said body and disposed in said slots and engageable with said gripping members to hold said gripping members in retracted position in said bores; and means `for shifting said retaining means longitudinally of said body and in said slots `from holding relation to said gripping members to permit outward expansion of said gripping members.

I5. In apparatus adapted to be anchored in a well casing disposed in a well bore: a -body lhaving a plurality of bores therein opening to the interior of Said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within said body and bores; said gripping members having longitudinal slots in their outer portions, retaining means externally of said body and disposed in said slots and engageable with said gripping members to hol-d said gripping members in retracted position in said bores; means for shifting said retaining means ylongitudinally of said body and in said slots `from holdin-g relation to said gripping members to permit outward expansion of saidgripping members; and means yfor shifting said retaining means longitudinally of said body and 4in said slots to retract said grip-ping members and hold said gripping members in retracted position.

i6. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body lhaving a plurality of bores therein opening to the interior of said body; gripping members in said 'bores expandable outwardly against the well casing in response to fluid press-ure within said body and lbores; said gripping members having longitudinal slots in their outer portions; a mand-rel movable within said body; retaining means externally of said body and -disposed in said slots and engageable with said gripping members to hold said gripping mem-bers in retracted position in said bores; and means operatively connected to said 4mandrel and movable thereby `for shift-ing said retaining means longitudinally of said body and in said sl-ots from holdin-g relation to said gripping members to permit outward expansion of said gripping members.

17. In apparatus adapted to Abe anc-hored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to Huid pressure within lsaid body and bores; said gripping members having longitudinal sl-ots in their outer portions and detents projecting in a lateral outward direction from the inner portions of said slots; retaining means externally of said body including bars in said slots engageable with said detents to hold said gripping Imembers in yretracted position in said bores; and means for shifting said retaining means longitudinally of said body in one -direction to shift said bars in said slots `from engagement with said detents to permit outward expansion of said kgripping members.

i8. In apparatus adapted to be anchored in a well casing disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to fluid pressure within `said body and bores; said gripping members having longitudinal slots in their outer portions and detents projectin-g in a lateral outward direction lfrom the inner portions of `said slots; retain-ing means externally of said body inc-luding 'bars in said slots engageable with said detents to hold said gripping members in retracted position in said bores; means -or shifting said retaining means longitudinally of said body in one direction to shift said bars in said slots yfrom engagement with said detents to permit outward expansion of said gripping members; and means for shifting said retaining means in the opposite longitudinal direction to reengage said bars with said detents to `retract sa-id gripping members and hold said gripping members in retracted position.

19. In apparatus adapted to be anchored in a well casin-g disposed in a well bore: a body having a plurality of bores therein opening to the interior of said body; gripping members in said bores expandable outwardly against the well casing in response to uid pressure within Isaid body and bores; said gripping members having longitudinal slots in their outer portions and detents projecting in a lateral outward direction `from the inner portions of said slots; retaining means externally of said body including ba-rs in said slots engageable with said detents to hold said gripping members in retracted position in said bars; a mandrel movable within said body; and means operatively connected to said mandrel and movable thereby for shifting said retaining means longitudinally of said body in one direction to shift said bars in 'said slots from 13 engagement with said detents to permit outward expans-ion olf said `gripping members.

20. In apparatus adapted to be ancho-red in a Well casing disposed 'in a well bore: a body having a plurality of bores therein opening to the inter-ior of said body; gripping members in said bones expandable outwardly against the well casing in Iresponse to iluid pressure within said body and bores; said gripping members having lon -gitudinal slots in their outer portions and detents project ing in a lateral outward direction from the inner portions of said slots; retaining means externally of said body including bars in said slots engageable with said detents to hold said Igripping members in Aretracted position in said bores; a mandrel movable Within said body; means operatively connected to said mandrel and movable thereby for shifting said retaining means longitudinally of said body in one direction to shift said bars in said slots from eng-agement with said detents to permit outward eXpansion of sa-id gripping members; and means for shifting 14 said retaining means in t-he opposite longitudinal direction to reengage Isaid bars with sa-id detents to retract said gripping members and hold said gripping members in .retracted position.

References Cited by the Examiner CHARLES E. OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, Examiner.

I. A. LEPPINK, Assistant Examiner.

Claims

1. IN APPARATUS ADAPTED TO BE ANCHORED IN A WELL CASING DISPOSED IN A WELL BORE: A BODY HAVING A PLURALITY OF BORES THEREIN OPENING TO THE INTERIOR OF SAID BODY; GRIPPING MEMBERS IN SAID BORES EXPANDABLE OUTWARDLY AGAINST THE WELL CASING IN RESPONSE TO FLUID PRESSURE WITHIN SAID BODY AND BORES; RETAINING MEANS ENGAGING SAID GRIPPING MEMBERS FOR HOLDING SAID GRIPPING MEMBERS IN RETRACTED POSITION IN SAID BORES, SAID RETAINING MEANS BEING MOVABLE LONGITUDINALLY OF SAID BODY FROM HOLDING ENGAGEMENT WITH SAID GRIPPING MEMBERS; AND MEANS FOR SHIFTING SAID RETAINING MEANS IN A DIRECTION LONGITUDINALLY OF SAID BODY FROM HOLDING RELATION TO SAID GRIPPING MEMBERS TO PERMIT THEIR OUTWARD EXPANSION.