US3026941A

US3026941A - Subsurface well bore tool

Info

Publication number: US3026941A
Application number: US704647A
Authority: US
Inventors: John F Muse
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1957-12-23
Filing date: 1957-12-23
Publication date: 1962-03-27
Anticipated expiration: 1979-03-27

Description

March 27, 1962 Filed Deo. 25, 1957 IFig. 1.

J. F. MUSE SUBSURFACE WELL BORE TOOL 5 Sheets-Sheet l A 7' TORNE YS March 27, 1962 J, F, MUSE 3,026,941

SUBSURFACE WELL BORE TOOL March 27, 1962 J. F. MUSE 3,026,941

SUBSURFACE WELL BORE TOOL Filed Dec. 23, 1957 3 Sheets-Sheet 3 John F. Muse INVENTOR.

A 7' TORNE V5 3,026,941 SUBSURFACE WELL BGRE TOOL John F. Muse, Whittier, Cali., assignor to Baker @il '5001s, Inc., Los Angeles, Calif., a corporation of Caliorma Filed Dec. 23, 1957, Ser. No. 704,647 19 Claims. (Cl. 16o-216) The present invention relates to subsurface well bore tools, and more particularly to tools capable of performing operations in well bores, such as squeeze and other cementing, high pressure acidizing, formation fracturing, swabbing, testing, producing, and tubing anchoring and catching.

An object of the present invention is to provide van improved retrievable subsurface ywell tool embodying retractable parts adapted to be expanded and set in a well bore, such parts being releasably held in a retracted position, in which relocation and retention of the parts in their retracted position is facilitated.

Another object of the invention is to provide a subsurface well tool having relatively movable parts and a lock device for vreleasably retaining such parts in a particular relative position, the lock device being manipulated to release such parts for relative movement and being easily relocated in a locking position to prevent such relative movement.

A further object of the invention is to provide a retrievable subsurface tool capable of being anchored in a well conduit against both upward and downward movement therewithin, the tool embodying an improved lock device for selectively preventing its anchoring in the well conduit, permitting anchoring in an upward direction, or permitting anchoring in a downward direction.

An additional object of the invention is to provide a retrievable well packer Iadapted to be anchored in packedoff condition in a well conduit to withstand high pressures from both below and above the packer, the packer embodying -an improved lock device for selectively preventing its anchoring in both directions or permitting its anchoring in both directions, the packer being automatically shiftable from a packed-oit condition anchored in one direction to la packed-off condition anchored in the opposite direction upon a reversal of the pressure in the well conduit acting upon the packer.

This invention possesses many other advantages, and has other obiects 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 present speciiication. lIt 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 deiined by the appended claims.

Referring to the drawings:

FlGURE l is `a longitudinal section through well apparatus disposed in a well casing, with its parts in retracted position;

FIG. 2 is a View similar to FIG. l, illustrating the ap1 paratus anchored in packed-off condition against downward movement in the well casing;

FIG. 3 is a view similar to FIG. l, illustrating the apparatus anchored in packed-off condition against upward movement in the well casing;

FIG. 4 is a view similar to FIG. l, illustrating the use of the reset track in shifting the well apparatus to a retracted position;

FIG. 5 is a longitudinal section through a portion of the apparatus, illustrating the parts in a relative position for withdrawing the apparatus from the well casing;

ine

FIG. 6 is a side elevational view, illustrating the relative positions of the parts for removing the major portion of the apparatus from the well casing;

FIG. 7 is an isometric projection, partly in Section, through the slip portion of the apparatus.

The invention is illustrated in the drawings as applied to and including a well packer A adapted to be anchored in packed-o condition in a well casing B against substantial longitudinal movement in both upward and downward directions. The well packer is lowered through the well casing to the desired setting point through use of a tubular string C, such as drill pipe or tubing extending to the top of the well bore and through which fluent material under pressure can be pumped for movement through the Vwell packer and for discharge into the well bore therebelow. The well packer A is capable of being anchored in packed-'01T condition in the well casing against upward movement therewithin and also against downward movement therewithin, the apparatus being capable of withstanding extremely high pressure differentials imposed upon it from below its packed-off location in the well casing, as well as from a region in the tubing-casing annulus above its packed-off location in the well casing.

The various elements of the well tool A can be positively locked in their retracted positions to permit upward and downward movement of the apparatus in the well casing. The tool can be easily released from its locked position to secure its anchoring in packed-off condition whenever desired. After the particular operation or operations in the well bore have been performed, the well packer can be manipulated to place its several parts in their retracted position once again, to enable the apparatus to be elevated in the well casing to a new setting location, to be entirely removed from the well casing, or to be lowered in the well casing to a new setting location. Such placement of the parts in their retracted position and the locking of such parts in such position is achieved in a simple manner, and without the necessity for critically Sensing the location of the parts from the top of the well bore.

As disclosed in the drawings, the well tool A includes an elongate body iii of tubular form which includes an upper head portion ll threaded onto the main portion of the body, this head portion having an upper threaded box l2 for threaded attachment to the lower end of the tubular string C. A lower body sub or adapter 13 is threadedly secured to the lower end of the main portion of the body l0, this sub also being provided with a threaded box 14 which can be used if need be, for attachment to a lower tubing section (not shown) or to the upper portion of a lower tool (not shown).

An upper expander l5 is movably mounted on the body of the tool, downward movement therealong being limited by engagement or" its lower end with a body flange 16. This expander coacts with an upper set of circumferentially spaced slip members 17 to anchor the well tool to the well casing against downward movement therewithin. Secured to t-he body at its lower portion is a lower expander 18, such attachment being illustrated as a threaded one in which the expander has internal left hand threads l@ meshing with companion left hand external threads Ztl on the body iii. An upwardly directed shoulder 21 on the lower expander engages a companion shoulder 22 on the body to limit upward threading of the lower expander on the body. The lower expander 13 is adapted to coact with a lower set of circumferentially spaced members 23 to anchor the well packer to the well casing against upward movement therein.

Disposed above the upper expander 15 is a packing structure 24 adapted to effect a fluid-tight seal against the wall of the well casing, to prevent passage of uids under high pressure in both directions between the body of the tool and the well casing B. The upper expander and upper set of slips 17 operate jointly with the packing structure 214 to anchor the well tool in packed-off position in the weil casing against downward movement, whereas the lower expander 18 and lower set of slips 23 act jointly with the packing structure 24 to anchor the well tool in packed-off condition in the well casing against upward movement therein. The sets of slips and the packing structure can be prevented from expanding outwardly into engagement with the Well casing by a latch or locking device 25 acting between the body 113 of the tool and the slips, which lock device is operable from the top of the well bore.

The upper set of slip members 17 are mounted in circumferentially and longitudinally extending slots 26 in an upper slip ring 27 which is slidable relatively on the body 1) of the tool. Each upper slip member 17 includes an upper gripping portion 28 having external wickers or teeth 29 facing in a downward direction to anchor the tool against downward movement in the well casing, the inner surfaces 30 of such gripping portions being inclined in a downward and inward direction for coaction with a companion externally tapered surface 31 on the upper expander, so that downward movement of the upper expander 15 within the slips shifts the gripping portion 28 outwardly into anchoring engagement with the well casing, and holds such gripping portion in such anchoring engagement. Each slip member 17 also includes an intermediate drag block portion 32 adapted to frictionally engage the wall of the well casing B. These drag block portions are normally urged into f-ull lengthwise engagement with the wall of the well casing by laterally disposed helical compression springs 33, there being a spring disposed in each groove 26, with its inner portion bearing against the base of the latter and its outer portion bearing against the base of a socket 34 formed within the drag block portion of each slip member.

The axis of the spring 33 is below the upper end of the drag block portion 32. When the spring 33 faces the drag block into lengthwise frictional engagement with the Well casing, the upper gripping portion 28 is disposed inwardly substantially out of the contact with the wall of the well casing. When the upper expander 15 is moved downwardly within the slips 17, it will shift the gripping portions 28 outwardly, pivoting the drag block portions 32 about the line of engagement of their upper ends 32a with the casing and away from the well casing. Each slip member 17 may be considered as a lever of the rst class, wherein the upper end 32a of the drag block portion acts as a fulcrum upon the casing, the spring 33 constantly tending to swing the lower portion of the slip member outwardly, to engage the drag block portion 32 fully with the well casing, and the gripping portion 28 inwardly out of engagement from the well casing. When the upper expander 15 moves downwardly within the gripping portion 28 it rocks the slip member about its point of engagement 32a with the casing B, to shift the upper gripping portion 28 into anchoring engagement with the wall of the well casing, and the lower portion of the slip member in a direction inwardly of the wall of the well casing.

When the expander 15 is out of engagement wit-h the gripping portion 28, the inner surfaces 30 of the gripping portions are inclined with respect to the expander surface 31. However, when the expander 15 moves into engagement with such surfaces 30, to tilt the gripping portions outwardly against the well casing, a full surface contact is made between the expander and the gripping portion.

Joint longitudinal movement of the upper slip members 17 within the well casing is secured by a retaining ring 35 which circumscribes the slip members immediately above their drag block portions 32, and which also holds them in transverse alignment with respect to each other.

This ring is located in external grooves 36 in the slip members, being adapted to engage the upper and lower sides of the grooves. The ring also serves to limit outward expansion of the slip members 17 under the inuence of the springs 33 prior to insertion of the tool in the well casing, by virtue of the engagement of the base of the slip grooves 36 with the retainer ring 35. This retainer ring bears against an outwardly directed interrupted ilange 37 at the upper end of the slip ring 27, in order that downward movement of the slip ring will cause the ange 37 to engage the retainer ring 35, which, in turn, engages the sides of the slip groove 36 and causes the slips to move jointly with the -retainer ring.

Below the drag block portions 32 the upper slip members are inclined in a downward and inward direction, terminating in lower foot portions 38 adapted to engage a stop ring 39 suitably secured to a lock ring 40 abuting the lower end of the upper slip ring 27 and also the upper end of a lower slip ring 41. The upper slip ring 27, lock ring 40 and lower slip ring 41 are secured together by longitudinally extending cap screws 42. The stop ring 39 is prevented from moving olf the lock ring 40 by one or more cap screws 43 extending through the stop ring 39 and threaded into the lock ring. The stop ring 39 limits the extent of outward expansion of the slip members 17, 23 -under the inuence of the springs 33 while the well tool is out of the well casing B.

The lower set of slips 23 is essentially the same as the upper set 17, being reversely arranged. It is unnecessary to the understanding of the present invention that a complete description of the lower set of slips and its holding arrangement be given. It is suticient to state that the lower set of slips 23 has a lower gripping portion 44 with teeth or wickers 45 facing in an upward direction to anchor the tool against upward movement in the well casing. It also has inner surfaces 46 inclined in an upward and inward direction for coaction with a companion tapered surface 47 on the Ilower expander 18, as well as drag portions y48 and spring 49 for urging the drag portions into engagement with the wall of the well casing. The lower slips 23 are held in appropriate position in circumferentially spaced longitudinal slots 50 in the lower slip ring 41 by means of a retaining ring 51 disposed in the slip grooves 52, the ring 51 being engageable with the lower slip ring ange 53. The upper ends 54 of the lower slips are formed as stop portions engageable with the stop ring 39 to limit outward expansion of the lower slip members 23 under the inuence of the springs 49,

The packing structure 24 is disposed above the upper expander 15. As specilically disclosed, it is in the form of a packing sleeve 55 the upper portion of which is molded, or otherwise secured, to a ring 56 threaded into a coupling sleeve 57, which is, in turn, threadedly secured to the lower portion of the body head 11. This packing sleeve 5S includes an upper base portion 58 and a lower base portion 59, both of which engage the periphery of the packer body 10. The lower base portion 59, however, is free from attachment to the packer body. The packing sleeve includes an upper lip forming portion 60, which is connected to the base 58 by an intermediate portion 61 having a generally cylindrical exterior 62 and a tapered inner wall 63 which is inclined in an upward and inward direction towards the base. The packing sleeve 55 also includes a lower lip forming portion 64 which is integral with a lower intermediate portion 65 having a generally cylindrical or slightly tapered exterior 66 and an inner tapered surface 67 inclined in a downward and inward direction toward the lower base 59. The

lip portions

60, 64 are inter-connected by a medial portion 68 including an inwardly directing rib, there being one or a plurality of radial ports 69 extending through the rib to establish communication between the exterior ofthe packing sleeve between the lip forming portions 6i), 64tand the interior of the packing sleeve.

The lock device 2S serves to releasably connect the slip structure to the body 10, so as to determine the ability of the body and the upper and lower expanders 1S, 18 to move relatively to the upper and lower sets of

slips

17, 23. The lock device can secure the slips to the body, wherein they cannot be engaged by either the lower expander 18 or the upper expander 15, under which conditions the apparatus is movable in both an upward and downward direction within the well casing, or the lock device can be released so as to permit relative longitudinal movement to occur between the body l of the tool, the upward expander l and the lower expander 18, on the one hand, and the upper and lower sets of

slips

17, 23, on the other hand, for the purpose of anchoring the well tool in packed-off condition within the Well casing against either a downward movement or upward movement therewithin.

The locking device 25 includes a lock key or pin 70 movable radially in a radial hole 71 in the lock ring 40, and being urged inwardly of the ring and against the body 1t) of the tool by a helical compression spring 72, the inner end of which bears against the pin 70` and the outer end of which bears against the lock sleeve 39. This key or pin 70 is yieldably retained within a lock groove, slot or track 73 formed in the body 10 of the tool, and including a generally horizontal or transversely extending leg portion 74 in the exterior of the body which merges into the lower portion of an upper longitudinal body groove, slot or track 7S, as well as into the upper portion of a lower groove, slot or track 76. The upper and lower grooves 75, '76 are preferably in alignment with one another, with one wall of the grooves, such as the right wall 77, being in alignment and actually forming continuations of one another. For a purpose that will be described hereinafter, the right wall 78 of the lower longitudinal groove or leg 76 is beveled in an outward direction away from the left wall 79 so as to function as a cam to shift the key 70y out of the groove. The upper end of the beveled portion 79 terminates a substantial distance below the point of intersection of the lateral groove 74 with the

longitudinal grooves

75, 76, so that the key "l0 will not be inadvertently cammed out of the grooves. The left wall Si? of the upper longitudinal groove or leg 75 is also beveled in an outward direction away from the right wall 77 of such groove, also providing a cam surface which can shift the key or pin 70 against the force of its spring 72 out of such groove, in a manner described hereinbelow. The lower portion of the upper bevel or cam surface 80 also terminates above the point of intersection of the lateral groove 74 with the

longitudinal grooves

75, 76.

As disclosed, the body of the tool is also provided with a reset slot, groove or track 81 extending longitudinally of the body to one side of and parallel to the upper longitudinal groove '75. The upper end of the reset groove 81 extends substantially as high as the upper end of the upper longitudinal groove 75, its lower end 82 terminating short of the lateral groove 74. However, the reset groove lies in a central plane which intersects the lower groove 74. The lower part Si of the base portion of the reset groove is tapered in a downward and outward direction to the periphery of the body it), to cam the yieldable key 70 from such groove, in the manner described hereinbelow.

In the operation of the apparatus disclosed, it is secured to the lower portion of the tubing string C with the yieldable key or pin "7@ in the lateral, intermediate grooved portion 74 of the slot `structure 73, which will retain the upper and lower sets of

slips

17, 23 in a neutral position relative to the upper and

lower expanders

15, 18, as disclosed in FIG. l, the packing sleeve 55 also being in retracted position, a position ywhich it inherently tends to assume. The

springs

33, 49 urge the drag portions 32,

48 of the upper and lower sets of slips outwardly against the well casing B, with their

gripping portions

28, 44 disposed inwardly of the well casing. The apparatus A is lowered in the well casing to the desired setting point therewithin, the retention of the pin 70 in the lateral slot portion 74 precluding relative longitudinal movement of the upper and

lower expanders

15, 18 with respect to the

slips

17, 23, for the purpose of anchoring them against the wall of the well casing. When the point in the well casing is reached at which the tool is to be set in packed-ott condition, the tubing string C is turned to the right, or in a clockwise direction as seen looking down from the top of the well bore, which will turn the body 10 of the tool in the same direction, arcuately shifting the slot structure 73 within the upper and lower slips and the lock key '70, which are prevented from rotating by the frictional engagement of the

drag portions

32, 48 of the slips against the wall of the vwell casing. The turning will continue until the right wall 7 7 of the slot structure engages the key 70, after which the tubing string C and body 1G of the tool can be lowered. The frictional engagement of the drag portions of the slips against the well casing resists or prevents downward movement of the slip structure within the well casing. In view of the fact that the key or pin 70 is now aligned with the

longitudinal slot portions

75, 76 of the slot structure, the body of the tool can be lowered within the

slips

17, 23 the upper longitudinal leg "75 of the slot structure merely sliding downwardly along the `lock pin 70.

The upper expander l5 moves downwardly with the body until it engages the tapered surfaces 30 of the upper slips 17, which prevents further downward movement of the expander 1S. The lower end of the packing sleeve 55 then engages the upper end of the expander 15, the downward movement of the body being transferred from the body head 11 to the packing sleeve 55, and to the upper expander l5, shifting the latter within the slips 17 and rocking them about their fulcrum points 32a of engagement with the well casing, to urge them into anchoring engagement with the wall of the well casing. After the upper expander l5 has been wedged within the upper slips 17, it cannot move downwardly to a further extent. Accordingly, downward movement of the body lil to a greater extent, which actually is only a slight distance, will move the upper head lill towards the expander 15, foreshortening the packing sleeve S5 and expanding it outwardly into sealing engagement with the wall of the well casing, such `as disclosed in FIG. 2. The tool has now been anchored in packed-olf condition against downward movement in the well casing and is capable of withstanding pressures from above the well packer, such as high pressures imposed on the fluid in the tubing-casing annulus D above the packing sleeve 55. Such pressures will cause the fiuid to by-pass the exterior of the upper portion of the packing sleeve, the huid under pressure passing inwardly of the packing sleeve through the ports 69 and then being exerted in an outward direction upon the

lower portion

64, 65 of the packing sleeve, holding it sealed off against the wall of the well casing, in the same manner as an upwardly facing cup or swab type of packing.

If pressure is now applied to the fluid in the tubing string C, the central bore through the packer body l@ and in the well casing B below the tool, such fluid pressure will act in an upward direction on the well packer shifting the body l@ in an upward direction. However, such pressure, then acting on the exterior of the lower portion of the packing sleeve 55, will pass upwardly therearound 'and in through the ports 69 to the interior of the packer, acting upon the upper portion 66, 6i of the packing sleeve to hold it sealed against the wall of the well casing, in much the same manner as a downwardly facing cup or swab type of packing element. With a pressure differential therebelow, which is also acting in an upward direction on the packing sleeve 55, the body of the tool will move upwardly, the packing sleeve remaining in sealedoil condition against the wall of the well casing. The body moves upwardly with respect to the slip structure, as permitted -by the fact that the lock pin 70 is still disposed in the

longitudinal portion

75, 76 of the slot 73. As the body moves upwardly, its flange 16 engages the upper expander and moves it upwardly out of the upper slips 17, the lower expander 18 then shifting upwardly within the lower slips 23 to rock them outwardly into anchoring engagement with the wall of the well casing. The parts then occupy the position disclosed in FIG. 3, in which the packing sleeve 55 is still packed-oli against the well casing B against the iluid pressure acting in an upward direction thereon, the lower expander 18 being wedged within the lower slips 23 to anchor the tool against upward movement in the well casing. At this time, the lock key or pin 70 is disposed in the lower longitudinal leg 76 of the slot or groove 73.

The fact that the upper and

lower legs

75, 76 of the slot, groove or track are in alignment with one another permits the well apparatus to transfer freely lbetween a condition in which the pressure is imposed on the apparatus in a downward direction, as provided by the presence of a fluid pressure differential in the tubing-casing annulus D above the packing sleeve 55, to an anchored packed-off condition in which the pressure is acting in an upward direction from below the tool, the body 10 of the tool merely shifting downwardly and upwardly as the case may be, and in the manner described above.

In the event it is desired to relocate the

slips

17, 23 in their neutral position with respect to the upper and

lower expander

15, 18 and retain them in such position, the reset track 81 can be employed to obviate the need for feeling for the point of intersection between the lateral groove 73 and the

longitudinal grooves

75, 76. It is merely necessary to set down on the tool, so that it is anchored in packed-off condition against downward movement as disclosed in FIG. 2 with the pin 70 in the upper groove 75, then imparting a left-hand turn to the tubular string C and the body 10 attached thereto. Such turning effort is resisted by the slip structure, in View of the fact that the

drag block portions

32, 48 are frictionally engaging the Wall of the well casing. As a result, the left cam surface 80 of the upper leg or longitudinal slot 75 will engage the pin 7) and shift it radially out of the groove 75 to a condition in which it will ride on the periphery of the body 10. A continuation of the left hand turn will locate the reset groove or track S1 under the pin or key 70, whereupon the spring 72 will snap the key into such groove. Further relative rotational movement cannot occur, since the sides of the reset track 81 are not beveled or tapered, there being an absence of any force component tending to cam the key 70 out of the reset track. The tubing string C and body 10 are now moved upwardly, the

drag block portions

32, 48 retaining the slip structure stationary. When the bottom cam surface 82 of the reset track 81 engages the pin 70, it will shift the pin radially outward, whereupon it will snap back into the lateral groove 74, wherein the

slips

17, 23 are in their neutral position relative to the upper and lower expanders 1S, 18, the parts being held in such neutral position. The apparatus can now be moved either upwardly or downwardly in the well casing.

The apparatus can also be relocated in a neutral position with the pin 70 in the lateral slot portion 74 Without moving it to the point of intersection between the lateral slot portion and the upper and lower

longitudinal leg portions

75, 76 of the slot in still another manner. Assuming the apparatus to be anchored in packed-oil condition against upward movement in the well casing, such as disclosed in FIG. 3, the body 10 of the tool can be moved downwardly a slight distance with the pin still disposed in the lower leg 76 of the slot, whereupon the tubing string C and the body of the tool are turned to the right. Since the right wall 78 of the lower leg of the slot is tapered, such right hand turning will cam the pin 70 out of the slot 76 and it will then ride on the cylindrical periphery of the body 10 of the tool. The tool need only be turned about a half or two-thirds of a revolution, the body of the tool then being lowered to a further extent until the pin 78 snaps into the lateral slot 74. It cannot move out of such lateral portion until the tubing string C and body 1G of the tool are turned to the right to place the pin 7o at the point of intersection between the lateral slot 'and the upper and

lower slot legs

75, 76.

It is to be noted that the upper end of the lower body sub or adapter 13 is disposed a substantial distance below the lower end of the lower expander 18 and that the lower expander is connected to the body by means of the

left hand threads

19, 20. This arrangement permits the apparatus to be withdrawn from the well casing after it has served its purpose therewithin without fear that the tool might be inadvertently anchored against upward movement in the well casing during its elevation therewithin. With the lower expander 18 wedged within the lower slips 23, to hold them anchored to the well casing, and preferably with the pressure in the tool relieved, the lower expander is prevented from turning. Accordingly, the tubing string C and the body of the tool can be rotated in a right hand direction, which will effect an upward feeding of the body 10 within the lower expander 18 until the body unthreads or unscrews completely from the lower expander, whereupon the latter drops down laterally into engagement with the lower body sub or adapter 13 (FIG. 5). When the lower expander rests upon the lower adapter 13, it cannot be shifted upwardly behind the lower slips 23 to expand them outwardly against the wall of the well casing. This is due to the fact that the relative downward movement of the lower slips along the body 10 is limited by engagement of the body shoulder with the lower end of the lower slip ring 41, as disclosed in FIG. 5. Under these conditions upward movement of the tubing string C and the body 10 will cause the shoulder 90 to engage the slip ring 41 and carry the slip structure with it within the well casing. From FIG. 5, it is evident that the lower expander 18, which has been disconnected from the body 10, is resting upon the lower adapter 13 and is out of wedging engagement with the lower slips 23. The apparatus can now be removed from the well casing without danger of inadvertent outward expansion on the lower slips against the well casing.

With the parts in the position disclosed in FIG. 5, the yieldable key 70 is disposed in the lower leg 76 of the slot 73. In order to expedite disconnection of the joints of tubing or drill pipe C at the top of the well bore, as the tool A is elevated in the Well casing B, it is desired to hold the stand of tubing above the rotary table (not shown) at the top of the well bore stationary, and rotate the entire tubing string C and the well tool A within the well casing to the right. With the present tool, such rotation will not rotate the slip structure with it, which is urged frictionally against the wall of the well casing. At each revolution of the body 10 of the tool in a right hand direction, the right beveled or cam side 78 of the lower slot leg 76 will engage the yieldable pin 70 and cam it out of the slot 76, whereupon it will slide freely relatively along the periphery of the body 10l until it snaps back into the leg 76 of the slot. A continuation of the turning of the body 10 of the tool to the right will cam a pin 70 out of the slot 76 once again, so that there is a disconnection between the body of the tool and the slot structure, permitting the body to turn relatively freely within the slot structure.

In theabsence of the cam 78 and the removal of the key or pin 70 out of the lower leg 76 of the slot, any attempt at rotating the tubular string C and the body of the tool would cause the slip structure to be dragged around the well casing, with potential damage to the parts.

The lower body sub or adapter 13 is also preferably connected to the body 10 of the tool by left hand threads 91, and this lower body or adapter has coupling teeth 92 at its upper end adapted to mesh with depending coupling teeth 93 on the lower end of the lower expander 18. This arangement insures the removal of substantially the entire well tool from the well casing in the event that it would otherwise become inadvertently fastened therein, as by reason of the breaking of a lower slip 23 and its wedging between the lower expander 18and the wall of the well casing B. Should this occur, rotation of the lower expander 18 would be prevented, in which event the tubing string C and the body 10 of the tool can be turned to the right, which would effect an upward threading of the body 10 of the tool with respect to the lower expander 18, until complete unthreading occurs of the

connection

19, 20, after which the coupling teeth 92 on the adapter 13 would engage the coupling teeth 93 on the expander 18. In view of such coupling engagement, the lower adapter is then prevented from rotating, the right hand rotation of the body 10 and the string C continuing and eiecting a disconnection of the body of the tool from the lower sub or adapter 13, in view of the left hand threaded connection 91 therebetween (FIG. 6). When such disconnection occur, the lower portion of the tool can be withdrawn through the lower expander 18, the shoulder 90 on the body engaging the lower slip ring 41 and insuring that the entire apparatus, with exception of the lower expander 18, lower sub or adapter 13 and broken slip portion (as 44 in FIG. 6) will be removed from the well casing. During the rotation of the body 10 of the tool in effecting the disconnection between the left-

hand threads

19, 20 and 91, the slip structure is not rotated around the Wall of the well casing, since the right wall 78 of the lower longitudinal slot 76 will repeatedly cam the pin 70 out of the slot, whereupon it will slide freely along the periphery of the body 10 of the tool.

The inventor claims:

1. In subsurface well bore apparatus: first and second members movable -relatively to one another; one of said members having a track including a lateral portion intersecting a longitudinally extending portion; the other 0f said members having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement; said one member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; means for shifting said pin generally radially from said longitudinally extending portion to allow its movement into said reset track; means for shifting said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said one of said members.

2. In subsurface well bore apparatus: rst and second members movable relatively to one another; one of said members having track including a lateral portion intersecting a longitudinal portion extending upwardly from said lateralfportion and a longitudinal portion extending downwardly from said lateral portion; the other of said memhaving a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said members and adapted to be disposed in said longitudinally extending portions to permit said relative movement; said one member having a longitudinally extending reset track lying in a plane intersecting said lateral portions; means for shifting said pin generally radially from one of said longitudinal portions to allow its movement into said reset track; means for shifting said pin generally radially from said reset track to allow its movement into said lateral portion;'and means for urging said pin generally radially toward said one of said members.

3. In subsurface well bore apparatus: first and second members movable relatively to one another; one of said members having a track including a lateral portion intersecting a longitudinally extending portion; the other of said members having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement; means for camming said pin generally radially `from said longitudinally extending portion for movement onto the adjacent surface of said one member to allow its longitudinal movement from said adjacent surface into said lateral portion; and means for urging said pin generally radially toward said one of said members.

4. In subsurface Well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a lateral portion intersecting a longitudinally extending portion; a generally radially movable pin carried by said outer member and adapted to be disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement;.said inner member having a longitudinally extending reset track lying in a plane intersecting said lateral por-tion; .means for shifting said pin generally radially from said longitudinally extending portion to allow its movement into said reset track; means for shifting said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said inner member.

5. In subsurface well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a lateral portion intersecting a longitudinal portion extending upwardly `from said lateral portion and a longitudinal portion extending downwardly from said lateral portion; a generally radially movable pin carried by said outer member adapted to be `disposed in said lateral portion to prevent substantial longitudinal movement between said members and adapted to be disposed in said longitudinally extending portions to permit such relative movement; said inner member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; means for shifting said pin generally radially from one of said longitudinal portions to allow its movement into said reset track; means for shifting said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said inner member.

6. In `subsurface Well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a llateral portion intersecting a longitudinally extending portion; a generally radially movable pin carried by said outer member and adapted to -be disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement; means for camming said pin generally radially from said longitudinally extending portion for movement onto the adjacent surface of said inner member to allow its longitudinal movement from said adjacent surface into said lateral portion; and means for urging said pin generally radially toward said inner member.

7. In subsurface well bore apparatus: rst and second members movable relatively to one another; one of said members having a track including a lateral portion intersecting a longitudinally extending portion; the other of said members having a generally radially moveable pin adapted to ybe disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and into said longitudinally extending portion to permit such relative movement; said one member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; a side of said longitudinally extending portion being tapered to engage and shift said pin `generally radially from said longitudinally extending portion to allow its movement into said reset track; an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said one of said members.

8. In subsurface well bore apparatus: first and second members movable relatively to one another; one of said members having a track including a lateral portion intersecting a longitudinal portion extending upwardly from said lateral portion and a longitudinal portion extending downwardly from said lateral portion; the other of said members having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said members and adapted to be disposed in said longitudinally extending portions to permit said relative movement; said one member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; one of said longitudinally extending portions having a tapered side to engage and shift said pin generally radially from said one longitudinally extending portion to allow its movement into said reset track; an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow movement into said lateral portion; and means for urging said pin generally radially toward said one of said members.

9. In subsurface Well apparatus: first and second members movable relatively to one another; one of said members having a track including a lateral portion intersecting a longitudinally extending portion; the other of said members having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement; a side of said longitudinally extending portion being tapered to engage and shift said pin generally radially from said longitudinally extending portion for movement onto the adjacent surface of said one me'rnber to allow its longitudinal movement from said adjacent surface into said lateral portion; and means for urging said pin generally radially toward said one of said members.

l0. In subsurface well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a lateral portion int'ersecting a longitudinally extending portion; a generally radially movable pin carried by said outer member adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement; said inner member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; a side of said longitudinally extending portion being tapered to engage and shift said pin generally radially from said longitudinally extending portion to allow its movement into said reset track; an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said inner member.

ll. In subsurface well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a lateral portion intersecting a longitudinal portion extending upwardly `from the lateral portion and a longitudinal portion extending downwardly from said lateral portion; a generally radially movable pin carried by said outer member adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said members and adapted to be disposed in said longitudinally extending portions to permit such relative movement; said inner member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; a side of one of said longitudinally extending portions being tapered to engage and shift said pin generally radially from said one longitudinally extending portion to allow its movement into said reset track; an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said inner member.

12. ln subsurface well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a lateral portion intersecting a longitudinally extending portion; a generally radially movable pin carried by said outer member and adapted to be disposed in said lateral portion to prevent substantial relative longitudinal movement between said members and in said longitudinally extending portion to permit such relative movement; a side of said longitudinal portion being tapered to engage and shift said pin generally radially from said longitudinally extending portion for movement onto the adjacent surface of said inner member to allow its longitudinal movement from said adjacent surface into said lateral portion; and means urging said pin generally radially toward said inner member.

13. In subsurface well bore apparatus: inner and outer members movable relatively to one another; said inner member having a track including a lateral portion intersecting a longitudinal portion extending upwardly from t-he lateral portion and a longitudinal portion extending downwardly from said lateral portion; a generally radially movable pin carried by said outer member adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said members and adapted to be disposed in said longitudinally extending portions to permit such relative movement; said inner member having a longitudinally extending reset track lying in a plane intersecting said lateral portion; a side of one of said longitudinally extending portions being tapered to engage and shift said pin generally radially from said one longitudinally extending portions to allow its movement into said reset track; an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said `lateral portion; a side of the other of said longitudinally extending portions being tapered to engage and shift said pin generally radially from said other longitudinally extending portion to allow its movement into said lateral portion; and means for urging said pin generally radially toward said inner member.

14. In subsurface well bore apparatus: body means; normally retracted means on said body means expandible laterally outwardly in response to longitudinal movement of said body means relative thereto; one of said means having a track including a lateral portion intersecting a longitudinally extending portion; the other of said means having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said body and normally retracted means and adapted to be disposed in said longitudinally extending portion to permit such relative movement; said one means having a longitudinally extending reset track lying in a plane intersecting said lateral portion; means for shifting said pin generally radially from said longitudinally extending portion to allow its movement into said reset track; means for shifting said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said one of said means.

l5. In subsurface well bore apparatus: body means; normally retracted means on said body means expandible laterally outwardly in response to longitudinal movement of said body means relative thereto; one of said means having a track including a lateral portion intersecting a longitudinal portion extending upwardly from said lateral portion and a longitudinal portion extending downwardly from said lateral portion; the other of said means having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said body means and normally retracted means and adapted to be disposed in said longitudinally extending portions to permit such relative movement; said one means having a longitudinally extending reset track lying in a plane intersecting said lateral portions; means for shifting said pin generally radially from one of said longitudinal portions to allow its movement into said reset track; means for shifting said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said one of said means.

16. ln subsurface well bore apparatus: body means; normally retracted means on said body means expandible laterally outwardly in response to longitudinal movement of said body means relative thereto; one of said means having a track including a lateral portion intersecting a longitudinally extending portion; the other of said means having a generally radially movable pin adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said body means and normally retracted means and adapted to be disposed in said longitudinally extending portion to permit such relative movement; means for camming said pin generally radially from said adjacent surface from said longitudinally extending portion for movement onto the adjacent surface of said one of said means to allow its longitudinal movement into said lateral portion; and means for urging said pin generally radially toward said one of said means.

17. In subsurface well bore apparatus: body means; normally retracted means on said body means expandible laterally outwardly in response to longitudinal movement of said body means relative thereto; said body means having a track including a lateral portion intersecting a longitudinally extending portion; a generally radially movable pin carried by said normally retracted means and adapted to be disposed in said lateral portion to prevent substantial relative longitudinal movement between said body means and normally retracted means and in said longitudinally extending portion to permit such relative longitudinal movement; said body means having a longitudinally extending reset track lying in a plane intersecting said lateral portion; a side of said longitudinally extending portion being tapered to engage and shift said pin generally radially from said longitudinally extending portion to allow its movement into said reset track; an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said body means.

18. In subsurface well bore apparatus: body means; normally retracted means on said body means expandible laterally outwardly in response to longitudinal movement of said body means relative thereto; said body means having a track including a lateral portion intersecting a longitudinal portion extending upwardly from said lateral portion and a longitudinal portion extending downwardly from said 4lateral portion; a generally radially movable pin carried by said normally retracted means and adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said body means and normally retracted means and adapted to be disposed in said longitudinally extending portions to permit such relative movement; said body means having a longitudinally extending reset track lying in a plane intersecting said lateral portion; a side of one of said longitudinally extending portions being tapered to engage and shift said pin generally radially from said one longitudinally extending portion to allow its movement into said reset track; and end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said lateral portion; and means for urging said pin generally radially toward said body means.

19. In subsurface well bore apparatus: a body; normally retracted slip means on said body; upper and lower expanders on said body engageable with said slip means to expand said slip means laterally outward to anchor said body against upward and downward movement in the well bore; said body having a track including a 4lateral portion intersecting a longitudinal portion extending upwardly from said lateral portion and a longitudinal portion extending downwardly from said lateral portion; a generally radially movable pin carried by said slip means and adapted to be disposed in said lateral portion to prevent substantial longitudinal movement between said slip means and said body and expanders and adapted to be disposed in said longitudinally extending portions to permit such relative longitudinal movement; said body having a longitudinal extending reset track lying in a plane intersecting said lateral portion; a side of one of said longitudinal extending portions being tapered to engage and shift said pin generally radially from said one longitudinally extending portion to allow movement of said pin into said reset track;an end portion of said reset track being tapered to engage and shift said pin generally radially from said reset track to allow its movement into said lateral portion; and means `for urging said pin generally radially toward said body.

References Cited in the file of this patent UNITED STATES PATENTS 2,389,869 Phipps Nov, 27, 1945 2,400,970 Baker May 28, 1946 2,429,910 Anderson et al Oct. 28, 1947 2,449,920 Williams Sept. 21, 1948 2,671,513 Clark Mar. 9, 1954 2,802,534 Conrad Aug. 13, 1957 2,871,949 Baker Feb. 3, 1959 2,878,878 Baker Mar. 24, 1959 2,893,491 Crowe July 7, 1959 2,924,434 Potter et al. Feb. 9, 1960