US2598340A - Well packer lock device - Google Patents

Description

y 1952 R. c. BAKER ET AL 2,598,340

WELL PACKER LOCK DEVICE Filed July 20, 1946 2 SHEETS-SHEET z W IN x /Afl 34 Q- JE lad? Cl .Saa flaw ill. @ym

IN V EN TORS QTTOENEV Patented May 27, 1952 2,598,340 7 WELL PACKER LOCK DEVICE Reuben C. Baker, Coalinga, and Thomas M. Ragan, Downey, Calif., assignors to Baker Oil Tools, Inc., Vernon, Calif a corporation of California Application July 20, 1946, Serial No. 685,023

Claims.

This invention relates to well devices, and more particularly to well packers adapted to be lowered within and anchored to well casings, liners, and similar conduits.

It is an object of the present invention to'provide a lock arrangement'capable of safely transmitting much greater loads between a well packer body and slip expander than heretofore possible, and of eliminating the tendency of the body to shift with respect to the casing in which the packer is anchored.

Another object of the invention is to provide a well packer whose body is anchored to a well casing through cooperable slips and an expander, and in which any tendency for the body to be rotated after setting of the well packer in the casing causes the slips to be embedded or engaged more firmly with the casing wall, thereby resisting the tendency of the body to rotate and facilitating its disintegration by a rotary drill bit.

Yet a further object of the invention is to provide a well packer lock device operable to expand packer slips into firm anchoring engagement with a well casing, and which also locks the well packer body against longitudinal movement. 1

Still another object of the invention is to utilize the engaging force between a well packer expander and its cooperable slips for locking the well packer body to the expander against longitudinal movement.

This invention has other objects'that will become apparent from a consideration of the embodiments shown in the drawings accompanying and forming part of the present specification. These forms will now be described in detail to illustrate the general principles of the invention, butit' is to be understood that such detailed description is not to be taken in a limited sense, since. the scope of the invention is best defined by the claims appended hereto.

Referring to the drawings:

Figure 1 is a partly sectional andelevational view of a well packer in a well casing, with it parts in retracted position;

Figure 2 is a partial longitudinal section of the well packer in partly tripped position;

Figure 3 is a partial longitudinal section of the packer'fully anchored in packed off condition within the casing;

through a'well packer, illustrating another embodiment of the invention; and

Figure 6 is a cross-section taken along the line 66 of Figure 5.

The invention is illustrated in the drawings'as applied to a well packer of the general type shown in United States Patents Nos. 2,121,051, 2,189,703 and 2222,0141.v Essentially, it consists of a central tubular body l0 secured to a string of tubing or drill pipe II, by means of which it is lowered through a well casing I2 to the desired point at which it is to be anchored in packed ofl condition. The packer is anchored against movement in an upward direction by a set of upper segmental slips l3 initially held in retracted position by shear screws l4 threaded into a conicallike expander I5 slidable on the exterior of the body Hi. This expander, whose-outer surface It tapers in an upward and inward direction, to conform to the inner taper I! on the slips I3, is also initially secured to the body by one or more shear screws l8.

Downward movement of the well packer is prevented by a plurality of segmental lower slips l9 having tapered surfaces 20 inclined downwardly and inwardly and adapted to slide along a companion external tapered surface 2| on the exterior of a lower conical expander 22 which is slidable on the body I 0. The lower slips are initially held in retracted position by shear screws 23 securing them to the lower cone 22, and the lower'cone is also held in an initial upward position with respect to the lower slips by one or more, shear screws 24 secured to the body. The lower screws 23, 24 have a greater shear value than the upper screws [4, I8, for reasons hereinafter brought out. r

A packing sleeve 25 is provided between the two expanders I5, 22, having external end flanges 26, 26 interlocking with inwardly extending flanges 21, 21 on the expander cones. The sleeve 25 is also provided with internal lip seals 28, 28 at its ends adapted to slidably seal with the external surface of the body III.

The upper slips [3, when in retracted position, are contained within the circumferential confines of a trip ring 29 secured to the upper end of the body. Similarly, the lower slips 19 are contained initially within the peripheral confines of an abutment at the lower end of the body, defined by a valve housing and guide 30 threaded on a lower body flange 3|. This valve guide 3!] depends from the body l0, and has a tripping ball seat 32 secured in its lower end by a shear screw 33. An arm 34 extends upwardly from the seat to hold a buoyant backpressure valve ball 35 in ineffective position to one side of the passage lob 3 through the packer body, in order to prevent its engaging a valve seat 36 at the lower end of the body while the tool is being lowered through the fluid in the well casing.

The tool is run in the well bore with the par-ts in retracted position, as shown in Figure 1. When the setting point is reached, a tripping ball 31 is lowered or pumped down through the tubular string until it engages the trip ball seat 32, closing the passage lllb against flow of fluid therethrough. Pressure can then be built up in the tubing string and body to force fluid under pressure through lateral ports 38 in the body into the elastic packing sleeve 25, inflating the latter against the casing and then elongating it in an upward direction to shear the screws l8, l4 holding the upper expander 15 to the body and the upper set of slips l; to this expander. Such upward movement of the cone l5 causes it to move within the slips l3 and forces the latter radially outward along the abuttingtrip ring 29 into engagement with the casi'ng .12 '(see Figure 2). The tubing string II and connected packer body II! are then elevated to'move the body, lower slips l9 and lower cone 2'2 upwardly with respect to the upper expander l5 and slips l3, foreshortenin'g or compressing the packing .unit 25 in a longitudinal direction and thereby expanding it outwardly against the casing. to form aleak-proof seal between the body and casing.

After the packing has been thus engaged with the casing, a continuation of the upward strain and movement on the packer body I0 shears the screws 24, 23 holding the lower expander 22 tothe body and the slips |'9 to the expander 22, the lower abutment 30, 3| shifting the-slips l9 longitudinally in an upward direction along the outer surface 2| of the expander and radially into anchoring engagement with the casing |2 '(see'Figu're 3) Such action occurs becaus fthe lower expander 22 is 'prevent'edfrom movingupwardl y by the casing engaging upper slips l3 and sealed ofi packing 25. It is to be noted that the wickers lid on the up er slips l3 face in-an upwarddirection and the wicker's |9a on the lower slips .in a downward direction, .preventing upward movement of the upper cone l5 and downward movement offthe iower cone 22,

and also precluding shifting of the intervening packing.

After both sets of slips have been firmly anchored to the casing, the packer body It! is incapable of moving in an upward direction because of the engagement of its abutment 30, 3|

with the lower slips I9, and a transmission of such upward force through the lower slips l9, lower expander 22, packing member 25, upper fixpander l5 and upper slips l3 to the wall of the casing l2. Downward movement of the packer body N is prevented by a one-way type of looking arrangement between the body, expander andslips. H

As shown in the drawings, the downwardly aeting lock is provided by the body ill, cone 22 ands lip's l9 themselves. In the Figure 1 embodiment of theinvention, the lower portion ofthe lower conical expander 22 is separated into segments by'spaced longitudinal extending slots or saw cuts running from the narrow lower end of theexpander and terminating just short of the expander portion receiving the packing flange 26, providing an arrangement in which the segments 39 of the slotted expander are-held together by the expander flange portion 3 1. The

segments thus formed have suflicient resiliency to permit their lateral movement to the slight extent necessary into and out of engagement with the exterior of the body. Initially, when unrestrained, the internal diameter of the expander is slightly greater than the external diameter of the body. However, the segments 39 are urged inwardly toward the body l0 upon exertion of a downward thrust on the latter member by a slight downward movement of the expander 22 within the slips l9 anchored to the casing l2. The cooperable tapered surfaces 2|, 20 "between the expander and slips cause forcing of the expander segments 39 inwardly into firm gripping engagement with the body l0; and the greater the downward force on the body, the greater is the wedging of the expander segments into the slips l9 and their inward forcing against the exterior of the body.

For the purpose of preventing potential slipping between the body l0 and split expander 22 upon downward movement ofthe former with respect to the latter, the exterior of the body is preferably formed with downwardly facing wickers or teeth 4| engageable with companion wickers or teeth 42 on the inner face of the expander segments 39. The teeth are so arranged as to permit upward movement of the packer body 10 within the lower expander 22 for the purposeof releasing the lower slips l9 from retracted position and moving them along the lower expander into anchoring engagement with the casing wall. However, subsequentdownward movement of the packer body produces its positive clutching engagement with the expander segments 39 and wedges the latter firmly into the slips l9, which, 'reaotively, force the expander segments inwardly of the body to prevent any possibility of disengagement between the body and expander teeth 4 '42.

For simplicity and economy of manufacture, the ratchet teeth 4|, 42 around the body and in the cone may be formed as a buttress type of thread, having the same pitch. The ratchet teeth are also preferably formed as a left hand thread. This is highly desirable since the subsequent drilling out of the well packer by a rotary .drill'bit may be facilitated thereby.

Substantially all of the packer parts are preferably made of readily drillable material, such as cast iron, aluminum or magnesium, to allow ready removal of the well packer from the casing under the disintegrating action of a drill bit.

Formore 'eiiective operation of the drilling tool, the .parts to bra-disintegrated should be held from rotating with the bit. The provision of the. left hand thread interconnection 4|, '42 between'the packer body l0 and lower conical expander 22 tends to'hold the body stationary under the action of a right hand rotating drill bit. Any tendency for the body to rotate in a right hand direction tends to feed the lower expander 22 downwardly into much firmer wedging relation with the slips I9 and the body H), the slips being urged against and into the casing 2 withgreater force,.'thus precluding, turning of the body.

The'threaded connection 4|, 42 also possesses the advantage of holding the body against rotation during unscrewing of the tubing string II from the body l0 after the packer has been set in the casing and performed its required function. The connection between the tubing string and packer bodyis' usually a left hand thread 50, whose disconnection is effected by right hand rotation of the tubing string I I. Such right hand hand thread 4|, 42 between the body Ill and lower expander, right hand body rotation tends to elevate the body, which cannot take place because of the abutting of the lower end of the body 3| with the lower slips l9, and the solid connection between these slips l9 and the upper casing anchored slips [3 through the lower expander '22, packing 35 and upper expander l5. As a result, any right hand rotary movement of the body l could only feed the expander 22 downwardly into firmer wedging engagement with both the lower slips l9 and body I0.

The embodiment of invention disclosed in Figure provides an arrangement in which the segments 43 of the split lower conical expander 44 are completely separated from one anothenbeing capable of moving bodily radially into coupling Or clutching engagement with the left hand threaded wickers or ratchet teeth 4| on the body ID, to insure that the entire length of the teeth 42 on each segment 43 isin full engagement with the companion teeth M on the body. These segments are coupled for joint longitudinally relative to the body I 0 and slips Is by a coupling ring or sleeve 45, which may be connected to the lower end of the packing 25in substantially the same manner as the expander 22 of the other form of invention is coupled to the lower end of its cooperable packing 25. The connection between the expander segments 43 and coupling ring 45 is effected by providing an internal ring groove 46 receiving an external flange 41 at the upper ends of the expander segments, and by the corresponding reception of an internal flange 48 on the ring in an external circular groove 49 formed collectively in the segments 43 below their external flange 41. This connection causes the expander segments 43 and coupling ring 45 to move in unison longitudinally, while permitting the slight amount of free radial movement of the expander'segments with respect to the body in being uncoupled from the body, during its upward movement, and firmly and positively coupled to the body upon its downwardmovement, which carries the conical expander segments 43 downwardly into the slips 1!! and radially inward, because of the wedging action produced by the cooperable tapered surfaces 2|, 2!) on the expander segments and slips.

As in the other embodiment, the body I0 and expander segments 43 are preferably formed with a left hand buttress type of threaded interconnection 4!, 42, to notonly provide a one-way clutching action between the body I Band split expander 44, but also to hold the body against rotation during its disintegration by a rotary drill bit, and during unscrewing of the tubing l I.

It is, therefore, apparent that lock devices for well packers have been provided in which a far greater load or longitudinal force may be transmitted from the body [0 through the expander and slips to the casing l2, since large load or force transmitting surfaces are present and operable. Large cooperable surfaces on the body and expander are effective to transmit the load between these two members, and relatively large tapered surfaces on the expander and slips are operable to transmit the load on the body through the slips to the casing. The effective surfaces between the body and expander extend almost entirely around the body and over a substantial length; the load transmitting surfaces between the expander and slips are also verysubstantial in both circumferential and tapered extent.

Thelarge load transmitting surfaces do' not tend to distort the parts and crush them inwardly, since the load transmission tending to collapse the body l0 inwardly is fairly uniformly distributed around the circumference of the body. Accordingly, relatively soft and easily drillable materials, such as magnesium, may be used for the body without impairing its ability to carry and transmit a large thrust or load safely.

The lock devices also provide the desirable feature of allowing easy upward ratcheting of the body l0 relative to the expander 22 or 44 in producing anchoring of the well packer in packed off condition against thecasing, while preventing relative downward movement between the body and the expander and slips I9 after thelatter have been anchored against thecasing. Moreover. the provision of the threaded interconnection 4|, 42, between the body l0 and expander or 44 and the wedging of the latter in the slips l9, which are anchored to the casing I2, provides the desirable element of holding the body against rotation in the event its removal from the well casing by a rotary drill bit becomes necessary.

Having thus describedour invention, what we claim and desire to secure by Letters Patent is:

1. A well tool, including a supporting member. split expansible and-contractible expander means movable with respect to said supporting member. slips movable by said supporting member along said expander means into engagement with a cooperable member, said expander means and supporting member having interengaging *ratchet teeth integral with said expandenmeans and supporting member and permitting longitudinal movement in one direction of said supporting member along said expandermeans in order to engage said slips with said cooperable member, said teeth locking said supporting member to said expander means upon longitudinal movement of said supporting member in the other direction, the locking surfaces of said ratchet teeth on said expander means'facing in the direction in which said supporting member is movable in engaging said slips with said cooperable member, the companion locking surfaces of said supporting member ratchet teeth facing in the opposite direction.

2. A well tool adapted to be set in a well conduit, including a body, split expansible and contractible expander means slidably mounted on said body, slips movable by said body along said expander means into engagement with said conduit, said expander means and body having interengaging ratchet teeth integral with said expander means and 'body and permitting longitudinal movement in one direction of said body within said expander means in orderto engage said slips with said conduit, said teeth locking said body to said expander means upon longitudinal movement of said body in the other direction. the locking surfaces of said ratchet teeth on said expander means facing in the direction in which said body is movable in engaging said slips with said conduit, the companion locking surfaces of said bodyratchet teeth facing in the oppositeteeth integral with said expander and body and permitting longitudinal movement in one direction or said body withinsaid expander in order to engage said slips with said conduit, said'teeth locking, said body to saidexpander -upon longitudinal movement ofsaid body in the other direction, the locking surfaces of said ratchet t eth on said expander facing in the direction in which said body is movable in engaging said slips with said conduit, the companion locking surfaces of said: body ratchet teeth facing in the opposite direction.

14, A well tool adapted to beset in a well conduit, including a body, a split expansible and contractible expander slidablymounted on said body and having :anexternal converging surface, interengaging ratchet teeth on said body and in said expander integral with said body and expander for locking said body and expander together upon movement of said body in one longitudinal directiion -andfor permitting movement oft-said body inrthe-otherlongitudinal direction relative-to said expander, the locking surfaces of said ratchet teeth onsaid body facing in the direction in which-said external surface converges and the lockingsurfaces of said ratchet teeth in said expander facing in the direction in which said surface diverges, and-slips slidable along the surface of said expanderintoengagement with said conduit and operable to force-said expander inwardly to maintain the mterengagernent of saidratchet teeth.

A well tool adapted to beset in a well conduit,includinga body, a split 'expansible and contractible expander slidably mounted on said body andhaving an-external downwardly converging surface, ratchet teeth on and integral with said body having downwardly facing locking surfaces,

ratchet teeth inand integral with said-expander having upwardly facing locking surfaces which areengageable with said downwardly facing surfaces of said body ratchet-teeth, and slips slidable along the surface of said expander into engagement with saidcondultand operable to force said expanderinwardly to maintain said ratchet teeth 'intflliengaged.

- 6. A well tool adapted to beset in a well conduit, including -a body, a sp lit expander slidably mounted on said body andihaving an external downwardly converging surface, a downwardly facing buttress left hand threadon said body, an

upwardly facing buttress left hand thread in said expander engageable with said body thread, and

slips slidable along the surface of said expander "body thread andfacing'in-the direction in which said external surface diverges, and slips slidable along-the surface-of said expander into engagement with said conduit and operable to force said expander inwardly .to maintainisaidrthreads inter-engaged.

, 8. A well tool, ,includingfa supporting member, a split expander slidable along {said-supporting member and having; :a converging surface, said supporting member having'a buttress, left hand ISO thread facing in one longitudinal direction, said expander having a buttress left-hand threadengageable with said supporting member thread and facing in the other longitudinal direction, and slips slidable along said expander surface into engagement with a cooperable member and operable to force said expander laterally to maintain said threads interengaged.

9. A well tool, including a supporting member. a split expander slidable along said supporting member and having a converging surface, said supporting member having a thread, said expander having a thread engageable withsaidsupporting member thread, and slips slidable along said expander surface into engagement with a cooperable member and operable to force said expander laterally to maintain said threads interengaged, said threads wedging said expander more firmly into said slips upon application of turning effort to said supporting member in one direction,

10. A well tool, including a supporting member, expander means movable with respect to said supporting member, said expander means comprising longitudinally extending segments separate from each other and a ring separate from said segments, coengaging means on said-segments and ring coupling said segments together for joint longitudinal movement while permitting their lateral movement, said supporting member and segments having interengaging ratchet threads, and slips movable along said segments into engagement with a cooperable member and operable to force said segments bodily laterally and firmly against said supporting-member to maintain said threads interengaged.

11. A well'tool adapted to be set in awell conduit, including a body, expander means movable on said body, said expander means comprising longitudinally extending segments separate-from each other and a ring separate from said segments, coengaging means on said segments and ring coupling said segments together forjoint longitudinal movement while permitting their lateral movement, said body and segments having interengaging ratchet threads, and slips movable along said segments into engagement with said conduit and operable to force said segments bodily inward against said body to maintain-said threads interengaged.

i2. A'well tool adapted to be set in a well conduit, including a body, an expander mounted on said body, slips cooperable with said expander and engageable with said conduit to prevent movement of said body in one longitudinal direction, a split expansible and contractible expander mounted on said body, slips movable by said body along said split expander and into engagement with said conduit to prevent longitudinal'movement of said body in the other direction, interengaging ratchet teeth on said body'and splitexpander integral with said body and split-expander and permitting longitudinal movement in one direction of said body within said-split expander in order to engage said slips with said conduit, said teeth locking said body to said split expander upon longitudinal movement of said body in the other direction the locking surfaces of said ratchet teeth on said expander .facinguin the direction in which said body is movable in engaging said slips with said conduit, the'companion locking surfaces of said body ratchet teeth facing in the opposite direction.

13. In a well tool adapted to be setin a wellv conduit, including a body, an upper expander slidably mounted on said body and having an external upwardly converging surface, upper slips slidable on said surface into engagement with said conduit, 2. split expansible and contracti'blelower expander slidably mounted on said body and havwith said conduit, said teeth locking said body to said split expander upon downward movement of said body, the locking surfaces of said body ratchet teeth facing downwardly, the locking surfaces of said expander ratchet teeth facing upwardly.

14. A well tool, including a supporting member, expander means movable with respect to said supporting member, said expander means comprising longitudinally extending segments separate from each other and a ring separate from said segments, coengaging means on said segments and ring coupling said segments together for joint longitudinal movement while permitting their lateral movement, and slips movable along said segments into engagement with a cooperable member and operable to force said segments 10 bodily laterally and firmly against said supporting member.

15. A well tool adapted to be set in a well conduit, including a body, expander means movable on said body, said expander means comprising longitudinally extending segments separate from each other and a ring separate from said segments, coengaging means on said segments and ring coupling said segments together for joint longitudinal movement while permitting their lateral movement, and Slips movable along said segments into engagement with said conduit and operable to force said segments bodily inwardly against said body.

REUBEN C. BAKER. THOMAS M. RAGAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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