US3552489A

US3552489A - Well packer apparatus

Info

Publication number: US3552489A
Application number: US781031A
Authority: US
Inventors: William O Berryman
Original assignee: Schlumberger Technology Corp
Current assignee: Schlumberger Technology Corp
Priority date: 1968-12-04
Filing date: 1968-12-04
Publication date: 1971-01-05
Anticipated expiration: 1988-01-05

Abstract

An illustrative embodiment of the present invention in retrievable well packers includes a body member carrying settable packing means adapted to sealingly engage a well casing wall, normally retracted slip means, and expander means movable downwardly relative to said slip means for shifting said slip means outwardly into gripping contact with a well casing wall, and hydraulic means above said packing means and coupled in force transmitting relationship thereto, said hydraulic means being responsive to greater fluid pressure in the well bore below said packing means than above said packing means for applying setting force to said packing means and said expander means to retain said packing means and said slip means in set positions.

Description

United States Patent [72] inventor William Berryman 3,387,658 6/1968 Lebourg l66/129X Hous 3,392,783 7/1968 Reed 166/129X [21] Appl. No. 781,031 3,399,729 9/1968 McGill 166/120 [22] Filed Dec. 4,1968 3,409,085 11/1968 Oliver 166/134 [45] P n J 5,1971 3,416,608 12/1968 Crow et a1. 166/134X 1 Assignee Schlumberger Twhnology Coqmrafion 3,426,846 2/1969 Young 166/120X i I New York Pririzary Examiner-David H Brown a corporation Texas Attorneys-Ernest R. Archarnbeau, Jr., William J. Beard,

David L. Moseley, Edward M. Roney, William R. Sherman s4 WELL PACKER APPARATUS and Stewart Moore 14 Claims, 8 Drawing Figs. [52] US. 6/ ABSTRACT: An illustrative embodiment of the present inven- /129 tion in retrievable well packers includes a body member carry- [51 Int. Cl. E211) 33/129, ing seflable packing means adapted to sealingly engage a well Ezlb 23/06 casing wall, normally retracted slip means, "and expander [50] Field ofsemch 166/120, means movable dow wardly relative to said slip means for 175/230 shifting said slip means outwardly into gripping contact with a well casing wall, and hydraulic means above said packing [56] References Cmd means and coupled in force transmitting relationship thereto, UNITED ST TES AT said hydraulic means being responsive to greater fluid pres- 3,088,532 /1963 Kellner 175/230 sure in the well bore below said packing means than above 3,277,965 /1966 G'rimmer.... 166/ 120 said packing means for applying setting force to said packing 3,338,308 8/1967 Elliston et a1. 166/120 means and said expander means to retain said packing means 9 3,356,142 12/1967 Crow et a1. 166/118 q and slip means in set positions.

97 v C a: I N 39 "warm 11.1- a

PATENIEDJAHSIQYI 3552.489

SHEETlUFS ATTORNEY W////am 0. Berry/nan WELL PACKER APPARATUS This invention relates generally to well packers used in well bores, and more specifically, to a production packer which can be easily manipulated in set position in a well bore, and which can be anchored in packed-off condition against movement in either direction in the well bore.

In installing aproduction string in a well, a packer is usually lowered on a pipe string and set above'the producing horizon in order to isolate it from adjacent zones in the well. The pipe string is then hung in a Christmas tree which is installed at the surface. In installing the Christmas tree, a certain amount of manipulation of the pipe string may be necessary, yet the exact location of the packer may be quite critical. Thus, it is desirable to provide a packer which can be precisely located at a predetermined setting position, and which is constructed and arranged such that the pipe string can be further manipulated at the surface during installation of the Christmas tree without disturbingthe setting position of the packer.

Fluid pressure may be imposed on a production packer from above or below. For example, it may be desirable to treat or,stimulate a producing zone before it is put on production and without removing the pipe string. In this case, pressure may be imposed from below. Moreover, subsequent remedial work may be anticipated. During actual production, it is possible that the pressure in the annulus above the packer may be greater than the pressure below it. In any event, such pressures lically operated by pressure from below. Although this arrangement may be quite satisfactory, the use of separate anchor assemblies provides for considerable complexity of the tool, increasing the cost as well as the chances of malfunctions. In some instances, such packers are difficultto' retrieve.

It is accordingly an object of the present invention to provide a new and improved retrievable well packer apparatus which can be set on a pipe string at a precise location in a well bore, and which permits further manipulation of the pipe string at the surface without disturbing the setting location of the packer.

Another object of the present invention is to provide a new and i rnproved production packer having only a single slip and expander combination for preventing movement due to pressure in either longitudinal direction in a well bore.

These and other objects are attained in accordance with the concepts of the present invention by a well packer apparatus including a body member-adapted for connection to a pipe string extending'upwardly to the earths surface. Normally retracted slip means are arranged to be expanded outwardly into gripping contact with a well. casing wall by a downwardly movable expander in order to anchor against downward movement. A settable packing structure is carried by the body member and is arranged to be expanded outwardly into sealing engagement with a well casing wall when subject to longitudinal compressive force. A series of piston and cylinder combinations are located above, and in coupled relationship to, said packing structure and are responsive to greater fluid pressure in the well bore below said packing structure than above said packing structure to provide downward force on the packing structure, thus increasing the compression on the packing as well as forcing the expander downwardly relative to the slip means in order to retain the slip means in gripping contact with the well casing wall. Means are also provided for locking the slip means and packing structure in expanded positions, while enabling a significant extent of longitudinal movement of the body member relative thereto, so that the pipe string can be manipulated as desired at the surface without disturbing the set condition or location of the packing and slips.

The present invention has other objects and advantages which will become more clearly apparent in connection with the following detailed description of a preferred embodiment taken in conjunction with the appended drawings in which:

FIG. 1 is a longitudinal view of a production packer accord ing to the present invention being lowered into a cased well bore on a pipe string;

FIGS. 2A and 2B are longitudinal sectional views, with portions in side elevation, of the well packer of the present invention with parts in running-in positions, FIG. 2B forming a lower continuation of FIG. 2A;

FIG. 3 is a cross section taken on line 3-3 of FIG. 28;

FIG. 4 is a schematic plan view of a coupling slot and lug configuration;

FIG. 5 is a cross section taken on line 55 of FIG. 2A; and

FIGS. 6A and 6B are views similar to FIGS. 2A and 2B but with parts in their relative positions when set in the well casing.

Referring initially to FIG. 1, a well bore B transverses earth formations and is lined with a casing C which is nonnally ce mented in place. A well packer 10 in accordance with the principles of the present invention is lowered into the well casing C on a pipe string P which, after the packer 10 is set, will channel produced fluids to the surface. The well packer 10 includes a central body member or mandrel 11 which carries a packing assembly 12 adapted to be expanded to pack off the annulus between the pipe string P and the well casing C. A set of normally retracted slips 13 are mounted on the upper end of a cage member 14 which has drag blocks 15 frictionally engaging the well casing. The slips 13 are adapted to be shifted outwardly into gripping contact with the well casing C by downwardly movable expander 16.

A pressure responsive assembly including a plurality of piston and

cylinder combinations

17, 18 and 19 is mounted above the packing assembly 12 as will be described in detail hereafter. A fluid bypass passage to aid in lowering the packer to setting depth is provided between the packing assembly 12 and the body member 11, and the bypass passage is arranged to be closed off at its upper end by a valve head 20 carried near the upper end of the body member 11. Moreover, a force balancing system is provided to aid in maintaining the valve head 20 in closed position when fluid pressure is imposed on the packer from below, the system including a locking assembly 21 which is cooperable with the upper end of the pressure assembly to enable the pressure in the well bore below the tool to act downwardly on a balance piston to be described hereinafter. In the drawings, the body member 11 is broken above the pressure responsive assembly to indicate that the body member can be quite long so as to enable considerable relative longitudinal movement between it and the packing assembly 12.

Turning now to FIGS. 2A and 2B, the body member 11 has a central bore 24 and extends throughout the length of the tool. The body member has a threaded box 25 at its upper end adapted for connection to the running-in string of tubing or drill pipe P, and a threaded pin 26 at itslower end adapted for connection to a string of pipe or to another well tool. An elongated sleeve member 27 is mounted on the body member 11,

the inner wall surface of the sleeve member being spaced laterally away from the outer wall surface of the body member over a considerable portion of its length to provide an annular fluid bypass passageway 28 opening at its upper end to the well bore as shown in FIG. 2A. The passageway 28 is arranged to be closed off by the annular valve head 20 which is threadedly secured to an upper portion of the body member 11, the valve head carrying a seal ring 29 which can seal against an internal valve seat 50 on the sleeve member 27 when the parts are telescoped together.

- The packing assembly 12 is mounted around the compression sleeve intermediate its ends, and includes a plurality of elastomeric packing rings 31 separated by annular spacer rings. The packing rings 31 are adapted to be expanded into sealing engagement with the wall of the well casing when subjected to longitudinal compression force. The upper one of the packing rings 31 is engaged by an upper annular abutment 32 which is slidable downwardly relative to the sleeve member 27, and the lower one of the packing rings 31 is engaged by a lower annular abutment 33 which is slidable upwardly relative to the sleeve member. The lower abutment 33 can be threadedly attached to the upper end of the expander 16 which is constituted by a sleeve portion 34 and a cone or wedge portion 35 having downwardly and inwardly inclined outer surfaces 39. Downward movement of the lower abutment 33 relative to the sleeve member 27 is limited by engagement with an annular shoulder 36 on the sleeve member. Several flow ports 37 are formed through the wall of the sleeve member 27 below the shoulder 36 which, together with several flow ports 38 through the wall of the sleeve portion 34, serve to communicate the bypass passageway 28 with the well bore below the packing assembly 12.

The cage member 14 is carried near the lower end portion of the sleeve member 27, the cage member being provided with a plurality of circumferentially spaced, radially directed recesses 41, each of which receives a drag block 15. Each drag block is urged outwardly into frictional engagement with the well casing wall by coil springs 42. A plurality of slip elements 13 are movably mounted on the upper end of the cage member 14 and have wicker-s or teeth 43 formed on their outer peripheries, an inner surface 44 on each slip element inclining downwardly and inwardly toward the sleeve member 27. The surfaces 44 are cooperable with the inclined surfaces 39 on the expander cone 35 to cause outward shifting of the slip elements 13 into gripping engagement with the well casing wall. Each slip element 13 is attached to the cage member 14 by-a rein 45 on the like having one end pivotally connected to a slip element by a pin 46, and the other end being pivotally connected to the cage member 14 by a pin 47 engaging in a lost-motion slot to enable the inward and outward movement of the respective slip elements relative to the cage member with the lower end surface of each slip element being supported by the cage member. Each slip element 13 is normally biased inwardly in retracted position by a spring 48.

A control housing 50 is threadedly attached to the lower end of the cage member 14, the housing initially extending downwardly below the lower end of the sleeve member 27. An annular, split clutch ring 51 is received within the housing, the ring having buttress type threads 52 on its outer periphery formed to face downwardly and cooperable with upwardly facing buttress type threads 53 formed on the inner wall of the housing 50. Due to its split construction, the clutch ring 51 is radially expansible a'nd contractible. The lower end portion 54 of the sleeve member 27 has a plurality, for example four, windows 56 in the wall thereof as shown in FIGS. 28 and 3, each window receiving a laterally movable latch element57 having teeth 58 formed on its outer periphery. The clutch ring 51 has companion teeth 59 formed on its inner periphery which are engageable with the latch element threads 58 when the latter is telescoped within the former. When the parts of the packer are in their running-in position as shown in FIGS. 2A and 2B, the latch elements 57 are positioned adjacent a reduced diameter portion 60 of the body member 11, the reduced diameter portion enabling inward movement of the latch elements. However, when the body member 11 is moved downwardly relative to the sleeve member 27, an enlarged portion 61 is provided with a backup surface 62 which, when positioned behind the latch elements 57, shifts them outwardly somewhat and prevents their inward movement. The coaction of the outer teeth 52 on the clutch ring 51 with the inner teeth 53 on the housing 50 is such that when the threads 58 on the latch elements 57 are engaged with the threads 59 on the clutchring 51, and the backup surface 62 is positioned behind the latch elements 57, any upward movement of the clutch ring 51 relative to the housing 50 will cause the

threads

58 and 59 to be cainmcd inwardly into more forceful engagementwith one another, thereby holding the sleeve member 27 in a lower position relative to the cage member l4.

In order to properly position the parts during lowering into the well bore, the housing 50 is provided with an inwardly extending control lug 64 which is cooperable with a jay-slot 65 formed in an outer peripheral portion at the lower end of the body member 11. The slot construction, shown in H6. 4, has a closed end channel 66 in which the lug 64 engages during downward shifting in the well bore, and which is connected by an inclined channel 67 with an open ended channel 68. Thus, as long as the lug 64 is in the closed end channel 66 as shown in FIG. 2B, the cage member 14 cannot move upwardly relative to the body member 11 and the slip elements 13 are held in spaced relation to the expander 16. However, by raising the body member 11 slightly, and then torquing to the right while lowering it, the lug 64 can be disengaged from the jay-slot 65 to enable downward movement of the body member 11 relative to the cage member 14. The lower end of the sleeve member 27 rests against an upwardly facing shoulder 69 on the body member 11, and the lower abutment 33 rests against the upwardly facing shoulder 36 on the sleeve member 27 so that the expander cone 35 and the slip elements 13 are held away from one another as long as the lug 64 is engaged within the closed end channel 66 of the jay-slot. Further, an upwardly facing shoulder 70 on the sleeve member 27 can engage a downwardly facing shoulder 71 on the cage member 14 to limit upward movement of the sleeve member relative to the cage member.

A series of hydraulically operable pistons and cylinders are mounted on the sleeve member 27 above the packing assembly 12. As shown in FIG. 2A, a plurality of

partitions

73, 74 and 75 are formed at spaced intervals along the sleeve member 27. Each partition has a

sleeve piston

17, 18 or 19 operatively associated therewith, each sleeve piston having an upwardly extending

tubular portion

76, 77 or 78 which is sealed with respect to a partition by a

seal ring

79,80 or 81, as well as an inwardly extending

flange portion

82, 83 or 84 which is sealed against intervening portions of the sleeve member 27 by

rings

85 or 86. Each

portion

76, 77 or 78 has one or

more slots

88 or 89 cut in the upper end thereof in order to communicate fluid pressure in the well bore above the packing assembly 12 with the respective lower surfaces of the

sleeve pistons

18 and 19. The lower surface of the sleeve piston 17 will also be subjected to a lesser fluid pressure than that below the packer via the medium of the upper packing ring 31. Alternatively, a spacer ring could be used to permit direct communication to the lower face of the sleeve piston 17, in which case a seal ring would be used to seal the portion 82 against the sleeve member 27.

Ports

90, 91 and 92 are formed through the wall of the sleeve member 27, eachport serving to communicate the pressure of fluids in the flow passageway 28 with the upwardly facing transverse surfaces of the respective sleeve pistons. The fluid passageway 28 is, as previously described, in communication with the well bore below the packing assembly 12, so that it will be appreciated that the upwardly facing transverse surfaces of each sleeve piston are subject to fluid pressure in the well bore below the packing assembly.

ln order to provide a force balancing system to prevent fluid pressure inside and below the body member 11 from pumping the valve head 20 upwardly and opening the bypass passageway 28, a pressure cylinder 95 is movably mounted on the body member 11 and has an annular cap portion 96 extending inwardly and sealed against the body member by a seal ring 97. A latch sleeve 98 is mounted inside the cylinder 95, the sleeve being longitudinally slotted to provide a plurality of circumferentially spaced spring fingers 99 extending downwardly and terminating in enlarged head portions 100. The head portions 100 have outer inclined surfaces 101 which are engageable with inner inclined surfaces 102 on the cylinder 95 to force the head portions inwardly in response to upward movement of the cylinder relative to the latch sleeve 98. An annular enlarged portion 103 of the valve head 20 provides a balance piston which is sealed against the inner periphery of the cylinder 95 by a seal ring 104. A pressure passage 105 is provided between the valve head 20 and the i valve seal 29 and enables the pressure to act downwardly on the upwardly facing transverse surface 106 of the balance piston 103.. l

A plurality of radially movable lug elements 110 are i movably received in openings 111 through the wall of the upper endportion of the sleeve member 27 as shown in FIGS. 2A and 5. The lug elements 110 are movable between inner or 1 retracted positions as-shown in FIG 2A, but are expandable outwardly to extended positions by engagement with an enlargedportion 112 of the valve head 20. The lug elements 110 can be biased inwardly toward retracted positions byan annular band spring 1l3or the like. When the body member 11 is telescoped downwardly within the sleeve member 27 during setting of the packer, the pressure cylinder 95 and the latch sleeve 98 will descend over the lug elements 110 so that the enlarged heads 100 on spring fingers 99 are located below the lug elements. The enlarged portion 112 of the valve head 20 a will extend the lug elements 110 to their outer positions to OPERATION In operation, the parts can be assembled as shown in the I drawings and attached to the lower end of the pipe string P for .insertion into a well bore. Duringlowering, the drag blocks 15 are forced to slide downwardly in frictional engagement with the wellcasing wall, and engagement-of the control lug 64 .within the closed end channel 66 prevents upward movement of the cage member 14 relative to the body member 11, thereby maintaining the slip elements 13 and the expander 16 in spaced relationship to prevent expansion of the slips. The packing rings 31 areretracted, and'fluids inthe well bore below the packer can pass upwardlybetween the packing assembly 12 and the well casing wa'll, as well as through the bypass passageway 28 formed between the sleeve member 27 and the body member llvia the expander ports 38 and the I sleeve member ports 37. t

At setting depth, the body member 11 is lifted slightly and 1 then loweredwhile torquing to the right in order to release the jay-slot 65 from the control lug 64 on the cage member 14.

The drag blocks function to hold the cage member 14 stationary so that the body member 11 can be moved downwardly relative thereto. When the body member 11 has been lowered sufficiently, the pressure cylinder 95 will telescope over the upper end of the sleeve member 27 and the valve 'head 20 will engage the seat .30. When the balance piston 103 comes into abutting relation with the upper end of the sleeve member 27, the pressure cylinder 95 is in position I to be latched; against upward movement as previously described, and the sleeve member can be forced downwardly by the weight of the pipe'string P to effect setting of the slip elements 13 and the packing assembly 12. Downward move- A merit will bring the expander cone 35 behind the slip elements 13 so that the cooperating inclined surfaces 39 and 44 will cause outward shifting of the 'slip elements until their teeth 43 bite into and grip the well casing wall as shown in FIG. 68. Now the expander 16 cannot move any further downwardly,

so that continued thrust on the sleeve member 27 will advance the upper abutment 32 toward the lower abutment 33'and cause the packing rings 31 to be compressed and expanded into sealing engagement with the well casing wall.

' The initial downward movement of the body member 11 relative to the sleeve member 27 will have positioned the backing surface62 behind the latch elements 57 to prevent inward movement thereof. Thus, as the sleeve member 27 is driven downwardly by the body member 11 relative to the slip elements 13 and the cage member 14, the latch elements 57 are forced to ratchet inside the clutch ring 51 which will trap thesleeve member 27 in the lowermost position to which it is moved. The sleeve member 27 cannot move upwardly as long as the backing surface 62 is behind the latch elements 57 because, as previously described, upward movement will only cause the clutch ring threads 59 to more tightly engage the latch element threads 58.

lnasmuch as there is a considerable extent of longitudinal movement possible of the body member 11 relative to the sleeve member 27 without removing the backing surface 62 from behind the latch elements .57, the pipe string P can be manipulated at the surface during installation of the Christmas tree without disturbing the setting positions of the slip elements 13 and the packing assembly 12. When the well is ready to be put on production, a certain amount of the weight of the pipe string P can be imposed on the body member 11 to assist in keeping the valve head 20 in closed position, as well as to help prevent any upward movement due to pressure from below.

The balance piston 103 on the-body member 11 also prevents upward movement of the body member due to pressure from below. The fluid pressure in the well bore below the packer is, channeled to the upper face 106 of the balance piston through the

ports

38 and 37 and the

passageways

28 and 105. Since the lower surfaces of the balance piston are subject to fluid pressure in the well bore above the packer (through the open lower end of the-locking pressure cylinder and the latch sleeve 98), the pressure difference is effective as downward force to counter balance the upward force on the body member 11 due to greater pressure from below.

As fluid pressure in the well bore below the packer 10 is increased, the set conditions of the packing rings 31 and the slip elements 13 are further maintained in the following manner. The fluid pressure in the well bore below the packing assembly '12 is transmitted through the bypass passageway 28 and via the

ports

90, 91 and 92 to the upwardly facing transverse surfaces of the

sleeve pistons

17, 18 and 19, while the lesser fluid pressure in the well bore above the packing assembly 12 is communicated via the

slots

88 and 89 to act on the downwardly facing transverse surfaces of the

sleeve pistons

18 and 19 and via the upper packing ring 31 to the downwardly T facing surface of the sleeve piston 17. The pressure difference provides a downward force on each'sleeve piston, the foreces being additive due to the series relationship of the sleeve pistons. Thus, the greater fluid pressure in the well bore below the packing assembly 12 acts in acumulative manner on the sleeve pistons to provide a downward force to the upper one of the packing rings 31. The force will increase the compression of the packing rings 31, and a portion of the force is also transmitted through the packing assembly 12 to the expander 16, forcing the cone 35 in a downward direction to restrain the slip elements 13 in tight gripping engagement with the well casing.

The well packer 10 is released from set position by applying a straight upward pull on the pipe string P at the surface. The lost motion available between the body member 11 and the pressure cylinder 95 will enable the enlarged portion 112 of the valve head 20 to be removed from behind the locking lugs so that the lugs can move inwardly andrelease the latch sleeve 98. As the body member 11 is moved upwardly, the bypass passageway 28 is opened to equalize pressures, and eventually the backing surface 62 will be displaced from behind the latch elements 57, enabling inward movement of the latch elements and release of the threads 58 from the threads 59 on the clutch ring 51. The open ended channel 68 and the inclined channel of the jay-slot 65 will automatically guide the control lug 64 back into the closed end channel 66 to relay the cage member 14 with respect to the body member 11. Of course, the release of compression force on the packing assembly 12 will permit the rings 31 to inherently retract, and the sleeve member shoulder 36 will pick up the expander 16 to permit the slip elements 13 to retract-Then the packer 10 can be shifted longitudinally in the well bore.

A new and improved well packer apparatus has been disclosed having settable packing and slips and a hydraulic system which responds to greater fluid pressure in the well bore below the packing than above the packing to retain both the packing and the slip in set positions. Since certain changes and modifications will occur to those skilled in the art in view of this disclosure without departing from the inventive concepts involved, it is the aim of the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the present invention.

lclaim:

l. A well packer apparatus comprising: a body member movable longitudinally within a sleeve member that carries settable packing means adapted to sealingly engage a well conduit wall; normally retracted slip means, and expander means movable downwardly relative to said slip means for shifting said slip means outwardly into gripping contact with the well conduit wall; and hydraulic means surrounding a portion of said sleeve member and capable of movement longitudinally along said sleeve member and with respect to said body member, said hydraulic means being coupled to transmit downward force to said packing means and via said packing means to said expander means to retain said packing means and said slip means in set positions in response to greater fluid pressure in the well bore below said packing means than above said packing means.

2. The well packer apparatus of claim 1 wherein said hydraulic means includes a plurality of members arranged in series relationship, each of said members having an upwardly facing transverse surface subject to the pressure of fluids in the well bore below said packing means and a downwardly facing resultant transverse surface subject to the pressure of fluids in the well bore above said packing means.

3. The well packer apparatus of claim 2 further including a bypass passage between said body member and said sleeve member; valve means on said body member adapted to close off the upper end of said bypass passage; and means for preventing said valve means from closing off said bypass passage during longitudinal movement in a well conduit.

4. The well packer apparatus of claim 3 further including balancing means on said body member adapted, when said bypass passage is closed by said valve means, for forcing said body member downwardly in response to greater fluid pressure in the well bore below said packing means than above said packing means.

5. A well packer apparatus comprising: a body member carrying a packing structure including a sleeve member and packing means on said sleeve member adapted to sealingly engage a well conduit wall; slip means and expander means movable downwardly relative to said slip means for expanding said slip means into gripping contact with a well conduit wall; hydraulic means coupled to packing means and responsive to greater fluid pressure in the well bore below said packing means than above said packing means for forcing said packing means and said expander means downwardly to retain said slip means in expanded positions; and releasable means for locking said slip means in expanded positions while enabling longitudinal movement of said body member relative to said sleeve member.

6. The apparatus of claim 5 wherein said releasable means includes laterally movable first gripping means on said sleeve member, second gripping means associated with said slip means and engageable with said first gripping means and a 8. The apparatus of claim 7 further including passage means for feeding fluid pressure in said passageway to said hydraulic means.

9. The apparatus of claim 5 wherein said hydraulic means includes at least one piston and cylinder means coupled in force transmitting relationship to said packing means. 7

10. The apparatus of claim 9 wherein said piston and cylinder means is provided with an upwardly facing transverse surface subject to fluid pressure in the well bore below said packing means, and a downwardly facing resultant transverse surface subject to fluid pressure in the well bore above said packing means.

11. The apparatus of claim 5 wherein said hydraulic means includes a plurality of piston and cylinder combinations which are coupled in series relationship to each other and in force transmitting relationship to said packing means.

12. The apparatus of claim 11 where in each of said piston and cylinder combinations is provided with an upwardly facing transverse surface subject to fluid pressure in the well bore below said packing means, and a downwardly facing resultant transverse surface which is subject to fluid pressure in the well bore above said packing means.

13. A well packer apparatus comprising: a body member adapted for connection to the lower end of a pipe string extending upwardly to the top of a well bore; a sleeve member mounted on said body member and laterally spaced therefrom to provide an annular fluid bypass passage therebetween that is open to the well bore at the upper end of said sleeve member; valve means on said body member and sleeve member for selectively closing off the upper end of said bypass passage; normally retracted packing means on said sleeve member adapted to be expanded outwardly into sealing engagement with a well conduit wall; normally retracted slip means and expander means below said packing means, said expander means being movable downwardly relative to said slip means for expanding said slip means outwardly into gripping engagement with a well conduit wall; drag means coupled to said slip means to enable relative movement; means responsive to downward movement of said sleeve member by said body member for expanding said packing means and said slip means; releasable means including coengageable latch elements on said sleeve member and said drag means for retaining said packing means and said slip means-in expanded positions; and means on said body member for locking said latch elements in engaged relation during upward and downward movement of said body member relative to said sleeve member.

14. The well packer apparatus of Claim 13 further including hydraulic means above said packing means and responsive to greater fluid pressure in the well bore below said packing means than above said packing means for exerting downward force on said packing means and through said packing means to said expander means to restrain said packing means and said slip means in expanded positions.

Claims

1. A well packer apparatus comprising: a body member movable longitudinally within a sleeve member that carries settable packing means adapted to sealingly engage a well conduit wall; normally retracted slip means, and expander means movable downwardly relative to said slip means for shifting said slip means outwardly into gripping contact with the well conduit wall; and hydraulic means surrounding a portion of said sleeve member and capable of movement lonGitudinally along said sleeve member and with respect to said body member, said hydraulic means being coupled to transmit downward force to said packing means and via said packing means to said expander means to retain said packing means and said slip means in set positions in response to greater fluid pressure in the well bore below said packing means than above said packing means.

6. The apparatus of claim 5 wherein said releasable means includes laterally movable first gripping means on said sleeve member, second gripping means associated with said slip means and engageable with said first gripping means and a locking surface on said body member for holding said gripping means in engagement with each other to prevent relative movement between said sleeve member and said slip means.

7. The apparatus of claim 5 further including a fluid passageway between said sleeve member and said body member which can be opened to the well bore above and below said packing means; and valve means on said body member for selectively closing off said passageway from communication with the well bore above said packing means.

8. The apparatus of claim 7 further including passage means for feeding fluid pressure in said passageway to said hydraulic means.

9. The apparatus of claim 5 wherein said hydraulic means includes at least one piston and cylinder means coupled in force transmitting relationship to said packing means.

13. A well packer apparatus comprising: a body member adapted for connection to the lower end of a pipe string extending upwardly to the top of a well bore; a sleeve member mounted on said body member and laterally spaced therefrom to provide an annular fluid bypass passage therebetween that is open to the well bore at the upper end of said sleeve member; valve means on said body member and sleeve member for selectively closing off the upper end of said bypass passage; normally retracted packing means on said sleeve member adapted to be expanded outwardly into sealing engagement with a well conduit wall; normally retracted slip means and expander means below said packing means, said expander means being movable downwardly relative to said slip means for expanding said slip means outwardly into gripping engagement with a well conduit wall; drag means coupled to said slip means to enable relative movement; means responsive to downward movement of said sleeve member by said body member for expanding said packing means and said slip means; releasable means including coengageable latch elements on said sleeve member and said drag means for retaining said packing means and said slip means in expanded positions; and means on said body member for locking said latch elements in engaged relation during upward and downward movement of said body member relative to said sleeve member.