US3318385A

US3318385A - Anchor device for well tools

Info

Publication number: US3318385A
Application number: US549096A
Authority: US
Inventors: Martin B Conrad
Original assignee: Individual
Current assignee: Individual
Priority date: 1966-04-12
Filing date: 1966-04-12
Publication date: 1967-05-09
Anticipated expiration: 1984-05-09

Description

May

Filed April 12,

9, 1967 M. B. CONRAD ANCHOR DEVICE FOR WELL TOOLS 3 Sheets-Sheet 1 INVENTOR. MART/N B. GOA/A340 ATTOR/VEVS May 9, 1967 M. B. CONRAD ANCHOR DEVICE FOR WELL TOOLS Filed April 12, 1966 5 Sheets-Sheet 2 z mhllllil May 9, 1967 Filed April 12, 1966 M. B. CONRAD ANCHOR DEVICE FOR WELL TOOLS Mae ff 3 Sheets-Sheet, 5

a; J I l 9,;

crr/ Q INVENTOR MAPWA/ B. CONEAD United States Patent 3,318,385 ANCHOR DEVICE FOR WELL TOOLS Martin B. Conrad, PO. Box 568, Carpinteria, Calif. 93013 Filed Apr. 12, 1966, Ser. No. 549,096 18 Claims. (Cl. 166-212) This is a continuation-in-part of my copending patent application Ser. No. 311,397, filed Sept. 25, 1963, now abandoned, for Anchor Device for Well Tools.

This invention relates to subsurface well tools and is particularly directed to a friction or shear anchor device adapted for operation within a well casing.

The principal object of this invention is to provide an improved form of anchor device which may be set and released by fluid pressure.

Another object is to provide a device of this type which is relatively short in length and which is capable of successful operation in shallow holes.

Another object is to provide such a device which operates solely by frictional contact with the casing, or which may be equipped with gripping elements having wicker teeth to bite into the inner surface of the casing.

Another object is to provide a device of this type employing an expansible, elastomeric sleeve together with a novel form of slotted casing-engaging member expansible into contact with the casing when fluid pressure is supplied within the sleeve.

Another object of this invention is to provide an anchor device utilizing an expansible sleeve for moving a casing-engaging member outwardly into contact with the casing, while having a means to prevent a gap from opening at the end of the casing-engaging member through which the sleeve could extrude.

Other and more detailed objects and advantages will appear hereinafter. 1

In the drawings:

FIGURE 1 is a longitudinal sectional view showing a preferred embodiment of this invention, the parts being in retracted, inoperative position;

FIGURE 2 is a perspective view of the casing-contacting member;

FIGURE 3 is a perspective view of the backing member;

FIGURE 4 is a sectional view taken substantially on the lines 44 as shown in FIGURE 1;

FIGURE 5 is a sectional view taken substantially on the lines 55 as shown in FIGURE 1;

FIGURE 6 is a sectional detail showing the parts in casing-engaging position;

FIGURE 7 is a perspective view showing a modified form of casing-contacting member;

FIGURE 8 is a perspective view showing a modified form of backing member for use with the device shown in FIGURE 6;

FIGURE 9 is a sectional detail showing another modification;

FIGURE 10 is a longitudinal sectional view of the anchor embodying a modified arrangement for eliminating clearances at the ends of the eXpansible assembly, with the anchor in the retracted position;

FIGURE 11 is an enlarged fragmentary longitudinal sectional view of one side of the anchor assembly of FIGURE 10, with the anchor expanded to grip the easing; and

FIGURE 12 is a view similar to FIGURE 11 but with a different means for closing out the gap at the ends of the expansible assembly.

Referring to the drawings, a tubular body generally designated 10 is adapted to be lowered into a well casing 11 on a tubing string 12. The tubular body 10 includes an axial cylindrical mandrel 113, provided with an in- Ice tegral ring 14 at its upper end. At its lower end the mandrel 1-3 is connected by threads 15 to the tubular part 16. The ring 14 has a skirt 17 and a downwardfacing abutment 18, while the tubular part 16 has an upward-facing abutment 19.

Mounted on the tubular body 10 and encircling the mandrel 13 between the

abutments

18 and 19 is an expansible assembly generally designated 20. This assembly includes an elastomeric sleeve 22 encircling the mandrel 13, a casing-contacting member 23, and a backing member 24 interposed between the sleeve 22 and the member 23. The upper end of the elastomeric sleeve 22 is enlarged and extends into a. recess 25 provided in the upper collar 26. Similarly, the lower end of the elastomeric sleeve 22 is enlarged and is received within the recess 27 of the lower collar 28. The upper collar 26 is engaged by the abutment 18 and forms a sliding seal with the inner cylindrical surface of the skirt 17, the seal ring 29 serving to prevent leakage. The upper collar 26 has a downward-facing abutment shoulder 30. The lower collar 28 rests on the abutment 19 and forms a sliding seal with the outer surface of the mandrel 13, the seal ring 31 serving to prevent leakage. The lower collar 28 has an upward-facing shoulder 32. The casing-engaging member 23 and the backing member 24 are each confined between the

shoulders

30 and 32 on the

collars

26 and 28.

Lips

33 and 34 on the

collars

26 and 28 limit outward expanding movement of the easing-engaging member 23.

The casing-engaging member 23 is formed as a tubular member and is provided with two series of

longitudinal slots

37 and 38. The slots 37 extend from the upper end and terminate short of the lower end; the slots 38 extend from the lower end and terminate short of the upper end. Thus, adjacent slots extend from opposite ends of the member 23 and define between the slots a series of circumferentially adjacent gripping elements 39. The slots are equally spaced and the gripping elements 39 are of equal width. The outer surface of the member 23 is provided with longitudinal grooves 40 which extend for substantially the full length of the member 23 and intersect the beveled surfaces 41. The slotted construction of the casing-engaging member 23 provides for substantially equal outward movement of the gripping elements 39, under uniform internal expansion force.

The backing member 24 is formed in a similar manner to the casing-engaging member 23 and is also provided with two series of

longitudinal slots

45 and 46, the slots 45 extending from the lower end. The member 24 is provided with a radial pin 47, which is adapted to slide into one of the slots 38 on the member 23 when the backing member 24 is positioned within the casing-engaging member 23, in order to stagger the slots in one member with respect to the slots in the other. In this way, the material of the elastomeric sleeve 22 i prevented from extruding outward through the

slots

37 and 38 in the easing-engaging member 23.

A plurality of ports 50 are provided in the mandrel 13 near its upper end. These ports communicate with the space 51 within the upper collar 26. The ports 50 also communicate by way of clearance space 51a and milled grooves 52 in the outer surface of the mandrel 13 with the inner surface of the elastomeric sleeve 22. The small clearance space 51a prevents extrusion of the elastomeric sleeve 22 under external pressures, and the milled grooves 52 insure that pressure fluid from the ports 50 reaches the interior of the elastomeric sleeve. Accordingly, when the pressure of fluid inside the tubular body 10 and mandrel '13 exceeds the fluid pressure within the casing 11, fluid under pressure passes from the interior of the mandrel 13 through the ports 50 and through the milled grooves into the interior of the elastomeric sleeve 22. The sleeve 22 expandsqradially, and the backing member 24 and casingeng-aging member 23 are expanded thereby. The gripping elements 39 defined between

slots

37 and 38 move outward along the

shoulders

30 and 32 of the upper and

lower collars

26 and 28, until the smooth outer surfaces of the gripping elements 39 engage the inner surface of the casing 11'. Fluid pressure within the space 51 acts on the upper end of the collar 26 and causes it to move downward with respect to the mandrel 13 to absorb any tension elongation of the mandrel 13 and to maintain

theshoulders

30 and 32 in contact with the

members

23 and 24. The exposed area of the sleeve 26 to the pressure fluid admitted 7 through the ports 50 is greater above the sleeve than below it.

This feature of the invention performs a valuable function in the successful operation of the anchor device of this invention by preventing extrusion of the elastomeric sleeve 22. With the fluidpressure urging the collar 26 downwardly, the shoulder 30 will always maintain its con tact, with theupper ends of the

members

23 and 24. This is despite the elongation of the mandrel 13 that will occur from the forces imposed upon it.

This effect can be seen in FIGURE 6, where the mandrel has experienced some elongation resulting from pressures applied to it. The collar 26 has moved downwardly because of the net piston area at its upper. end which is sealed at its outer periphery by the O-ring 29. The shoulder 39 of the-collar 2 6, consequently, is held against the upper ends of the

members

23 and 24.

With the collar 26 held in engagement with the ends of pull on the mandrel is transmitted through the shoulder 32 of the lower collar 28 to the bottomend of the mem-' ber 23; Extrusion of the sleeve 22 through suchfa gap at. the upper end of the assembly 20, of course,v would cause malfunction of the anchor.

In operation, the tubular member 10 is lowered into the 'casing'll with the parts in position as shown in FIGURE 1; The. longitudinal grooves 401in the casing engaging member 23 serve as passages for fluid within the casing.

The assembly 20 may be employed to anchor the lower end'of the tubing string '12 with respect-to the casing for any desired purpose. Another tool, for example, are-v trievable bridge plug, may be carried on the tubing string 12 above or below the tubular member 10. When the device rea'chesthe desired elevation within the casing 11, the. pressure inside the'tubing 'string 12 is increased, thereby causing fluid under pressure to enter the annular space between the mandrel 13 and the elastomeric sleeve 22.

The pressure of the fluid acts to move'the gripping elements 39 of the slotted member, 23. into engagement with the inner surface ofthe casing, as shown in FIGURE 6. The

parts

13, 23, and 24 are formed of metal, preferably steel, so that they have sufiicient resilience to contract to their initial :shape when theqpressureis equalized inside and outside the elastomeric sleeve 22..

In a modified form of my invention shown in FIG- and 8, the casing-engaging member 23a and the backing member 24aare similar to that previously described except that the slots are located in diflerent positions; Two series of slots are. provided; the slots 38a extend for the major portion of the length of the member 23a but terminate short of the ends thereof, and the slots 37a in the other series. each comprise aligned slot portions extendingfromthe extreme ends of the member 23a but terminate short of the mid-portion thereof. The gripping elements 39a are defined between

adjacent slots

37a and 38a. The

slots

45a and 46a in the backing member 24a are similar to the

slots

37a and 38a, respectively. The radial pin 47a enters one of the slots 37a and the casingengaging member 23a, to hold the slots in the

members

23a and 24a in staggered relationship.

In the modified form of the invention shown in FIG- URE 9, wicker teeth are provided on the outer surfaces of the gripping elements 3%. The wicker teeth 55 are preferably located on a cylindrical surface of smaller diameter than the diameter of the cylindrical defined by the ends 56 of the elements 39a. In this way, the wicker teeth are protected against dragging contact with the interior surface of the casing 11 as the device is lowered into the well.

When the gripping elements 3% are expanded by means of the pressure-energized elastomeric sleeve 22, however, the elements 39b elastically deform and bow sufficiently to engage the wicker teeth 55 into the inner surface of the casing 11. The wicker teeth bite into the casing and hence a shear resistance load as well as a friction load opposes longitudinal movement of the anchor device Within the casing 11. The device ofFIG- URE 9 may employ a casing-engaging member and backup member of the form shown in FIGURES 2 and 3 or FIGURES 7 and 9.

When the outside surfaces of the gripping elements 39 are smooth, the anchor device may be employed as a drag-block assembly. The unstressed free-diameter of the gripping elements may be made larger than the inside diameter of the casing, and in this Way, a friction drag force may be provided and without actually anchoring the device against longitudinal movement.

' Although the slots in the

members

23, 24, 23a, and 24a are shown in the drawings as extending axially of the members, it is to be understood that this is by way of illustration only, and the slots operate satisfactorily even though they may have some inclination or helical lead. The word longitudinal as used in connection withithese slots in the specification and claims applies to slots which are axial or which have a helical lead with axsubstantial longitudinal component. I

As an example of relative sizes of parts which may be usedin carrying out this invention, the casing-contacting member may have an outside diameter when unstressed of 3.795" for contacting the inside surface of 4 /2" casing,

and the inside diameter may be'-3.06 2". The grooves may be /2" wide and A" deep. The slots may be from to A." wide. The backing member may be 3.062 'outside diameter and 2.875" inside diameter, and the slot may be to, /s" wide. All of these dimensions are approximate. When the parts are made of steel with these. diameters and thicknesses, they contract to initial unstressed size after pressure is released within the elastomericsleeve, and with substantially no permanent deformation.-

The embodiment of the invention illustrated in FIG- URES 10 and 11 provides a modified arrangement for eliminating any clearances at the ends of the expansib'le assembly 20 to assure retention of the elastomeric sleeve. In the construction of FIGURES 10 and 11, the pressure from the fluid reacts against the movable collar through a bead at the end of the expansible sleeve, rather than directly contacting the collar as for the collar 26 in the design of FIGURE 1. This eliminates the need for a seal around the outer periphery of the movable collar.

As shown in FIGURES'IO and 11, a short tubular member 57 is threaded onto the bottom end of the tubing string 12 and connects by threads, in turn, to the upper end of a cylindrical body in the form of a mandrel 58. The bottom end of the mandrel 58 is threadably connected to a depending tubular element 59. The mandrel 58 has upper and lower sets of openings 60 and 61, respectively, that provide communication between the bore of the mandrel and the interior of an elastomeric sleeve 62 that corresponds to the sleeve 22 of the previously described embodiment. The expansible assembly 20, which includes the casing-contacting member 23 and the backing member 24, circumscribes the sleeve 62.

At the ends of the assembly 20 are collars 64 and 6 having

radial shoulders

66 and 67 for engaging the ends of the

members

23 and 24. Above the radial shoulder 67, the collar 64 includes a downwardly and inwardly inclined surface 68 from the upper ends of which projects an axially directed flange portion 69. Similarly, the collar 65 has an upwardly and inwardly inclined surface 70 and a flange portion 71 extending downwardly from this surface.

The tubular member 57 above the collar 64 has a downwardly and outwardly inclined end surface 73 that is convergent with the surface 68 of the collar 64 and extends to the inner wall of the flange 69 just above the surface 70. The outer periphery of the tubular member 57 is recessed to receive the flange 69, which is engaged by a shoulder 74 on the member 57. Therefore, when the member 57 is threaded into place so that its inner shoulder 75 bottoms against the upper end of the mandrel 58, the collar 64 is retained between the shoulder 74 of the member 57 and the upper end of the expansible assembly 20.

The bottom portion of the anchor is generally the same, with a downwardly inclined surface 76 on the member 59 extending from the flange portion 71 of the lower collar 65. The lower tubular member 59 is threaded onto the mandrel until its inner shoulder 77 engages the bottom end of the mandrel, which thereby retains the collar 65 between the outer shoulder 78 of the lower tubular member 59 and the bottom end of the expansible assembly 20. The collars 64 and 65, together with the

shoulders

74 and 78 of the

tubular members

57 and 59, position the

members

23 and 24 axially of the mandrel 58.

The elastomeric sleeve 62 is provided with an annular rib or bead portion 79 extending into the wedge-shaped space defined between the

surfaces

73 and 68 of the

members

57 and 64, respectively. A similar annular rib 80 is received between the surface 76 of the lower tubular member 59 and the inclined surface 70 of the collar 65. Additional

small end beads

81 and 82 on the sleeve 62 fit in recesses in the

members

57 and 59, respectively. Thus, the ends of the sleeve 62 are retained.

Operation of the anchor in the embodiment of FIG- URES and 11 is basically the same as that described above. Fluid pressure within the mandrel 58 has access through the openings 60 and 61 to the inside of the sleeve 62, thereby expanding the assembly to frictionally engage the casing 11. This locks the anchor in position. However, the fluid pressure does not act directly upon the end of a piston in taking up the clearance at the ends of the expansible assembly 20 when elongation of the mandrel occurs. The fluid pressure from within the sleeve 62 will force the upper rib portion 79 tightly into the space between the

surfaces

68 and 73. The resilient rib 79 of the sleeve 62 transmits the fluid pressures to the inclined surface 68 of the collar 64. This produces a downward reaction on the collar 64, forcing it against the upper end of the assembly 20. Therefore, as may be seen in the enlarged illustration of FIGURE 11 where the mandrel has experienced some elongation, the collar 64 is shifted downwardly by the force imposed upon it by the rib 79 of the sleeve 62, which in turn receives the pressure applied to the interior of the mandrel 58. This downward movement of the collar 64 takes up the end clearance so that a gap will not open up at the upper end of the assembly 20, and the sleeve 62 will not be extruded outwardly.

A similar result is obtained at the lower end of the anchor, where the fluid pressure forces the rib. 80 against 6 the surfaces 70 of the collar 65. This holds the radial shoulder 67 of the collar 65 in contact with the shoulder formed by the bottom end of the assembly 20. Again, zero clearance is maintained and the sleeve is retained against extrusion.

As the invention is illustrated in FIGURES 10 and 11, there is a provision for eliminating a gap at either end of the assembly 20, so that the anchor is designed to withstand both upward and downward loads. In the embodiment of FIGURE 1, the device is intended to be under a pull from'above, so that only the upper collar 26 in that arrangement is provided with a piston area to take out the end clearance. The load on the bottom collar 28 necessarily will hold the abutment shoulder 32 in engagement with the bottom end of the assembly 20. Consequently, there is no need for a means to take out clearances at that location. However, the design of FIGURE 1 readily could be constructed for withstanding loads in two directions by making the collar 28 similar to the upper collar 26.

In the illustration of FIGURE 11, the anchor is shown in a condition where no end load is applied, and both

collars

66 and 67 have been caused to move inwardly with respect to the expansible assembly 20. This is for purposes of illustration, indicating how clearances are eliminated at the two ends of the assembly 20. Normally, however, there will be a load either upwardly or downwardly on the unit, so that only one of the collars will move inwardly. The other collar then will transmit the axial loads from the mandrel to the expansible assembly 20. For upward loads, the forces are transferred from the mandrel through the shoulder 78 of the tubular member 59 to the flange 71 of the lower collar 65, and from the latter member to the bottom end of the casingengaging member 23. Similarly, downward loads are taken out through the shoulder 74 of the upper tubular member 57 to the flange 69 of the collar 64, and through the collars shoulder 66 to the upper end of the member 23.

In the embodiment of FIGURE 12, there is no moving collar on the anchor, but nevertheless end clearances are eliminated, so that the sleeve is fully supported throughout its length. In this construction, the anchor element is made to bend, which elongates it in the direction of the mandrel axis so that a gap does not occur when the mandrel stretches. The elastomeric sleeve 83 is held at its upper end by a fixed collar 84 that threads onto the upper end of the mandrel 85. An annular rib 86 on the member 84 fits into a complementary recess at the end of the sleeve 83 to retain the upper end of the sleeve. A similar collar 87 at the bottom of the elastomeric sleeve has an annular rib 88 that retains the lower end of the sleeve. The collars 84 and 87 present

radial shoulders

89 and 90, respectively, at the upper and lower ends of the expansible anchor assembly 91.

The outer segmented anchor element 92 is adapted to engage the casing 11 and circumscribes a backing member 93. Annular grooves at the upper and lower inner surfaces of the elements 92 receive annular ribs 94 and 950i" the backing member 93.

The segmented casing-engaging member 92 includes a central outer surface portion 96 which is parallel to the axis of the mandrel. Above the central portion 96 is a surface 97 that inclines inwardly toward the axis at a shallow obtuse angle relative to the surface 96. Similarly, a surface 98 inclines inwardly at the same angle from the lower end of the central portion 96.

As a result of this construction, fluid under pressure entering through

openings

99 and 100 in the mandrel exerts a force against the sleeve 83 to expand the members 92 and 93 outwardly in the usual manner. This will urge the central portion 96 of the segmented member 92 flat against the inner wall of the casing 11. Pressure also will be exerted opposite the

inclined surfaces

97 and 98 at the upper and lower portions of the member 92. This will tend to bend the member 92 about the points 101 and 102 where the

surfaces

97 and 98, respectively, connect with the central portion 96. When the member 92 bends about the point 101, the upper inner corner 103 of the member 92 swings through an arc.'

Similarly, bending about the fulcrum 102 causes the lower inner corner 104, to pivot through an arc. ternal pressures, therefore, cause the

end portions

97 and 98 to approach alignment with the central outer surface, 96 as the member 92 is bent. The effect is an elongation of the member 92 as the arcuate movement of the corners 103 and .104 causes them to have axial increments of travel. This elongation of the member 92 compensates for the stretching of the mandrel 85, thereby preventing a gap from opening up at the

shoulders

89 and 90. As before, therefore, the sleeve 83 is retained and prevented from extrusion.

ribs

94 and 95 on the backing member 93 cause the backing member to elongate with the member 92 as the bending movement takes place, so that there will be no space between the backing member and the casing-engaging member 92 where the sleeve 83 might enter.

It can. be seen, therefore, that the device of this invention can be manufactured in different forms, while still retaining the advantageous feature of the Zero clearance at the ends of theexpansible portion of the anchor during all operating conditions. Regardless of which embodiment of the invention is utilized, the expansible sleeve is always fully supported and can never be forced out of a gap under the influence of the pressure within the anchor.

Having fully described my invention, it is to be understoodthat I do not wish to be limited to the details set forth above, but my invention is of the full scope of the f appended claims.

I claim:

1. In an anchor device for use within a well casing, the combination of: tubular body means including a mandrel adapted to be lowered into the Well casing, an elastomeric sleeve encircling said mandrel, a casing-engaging member disposed around said elastomeric sleeve and having a plur'ality of longitudinal slots defining a series of circumferentially adjacent gripping elements, shoulders on the tubular body engaging opposite ends of said member to prevent longitudinal movement thereof relative to said tubular body while permitting said opposite ends of said member. to move in a radial direction, each slot extend- The in- The connections formed by the. annular being communication between the interior of said mandrel and the interior of said elastomeric sleeve, whereby fluid under pressure within said mandrel may expand said elastomeric sleeve and cause it to expand said backing strips and said gripping elements, outward to engage said gripping elements with the casing.

2. In an anchor device for use within a well casing, the

.co'mbination'of: a tubular body including amandrel adapted to be lowered into the well casing, an elastomeric sleeve encircling said mandrel, a casing-engaging member havinga plurality of longitudinal slots defining a series of circumferentially adjacent gripping elements,

shoulders on the tubular body engaging opposite ends of said member to prevent longitudinal movement thereof relative to said tubular body while permitting said opposite ends of said member to move in a radial direction, each slot extending from one end of said member and terminating short of the other end of said member, adjacent slots extending from opposite ends of said member so that each gripping element is joined at opposite ends to next adjacent gripping elements, a series of circumferentially adjacent backing strips interposed between said elastomeric sleeve and said casing-engaging member, said backing strips being staggered with respect to said gripping elements to bridge the slots and to prevent portions of said elastomeric sleeve from passing into said slots, and a port in the mandrel establishing fluid communication between the interior of said mandrel and the interior of said elastomeric sleeve, whereby fluid under pressure within said mandrel may expand said elastomeric sleeve and cause it to expand said backing strips and said gripping elements outward to engage said gripping elements with the casing.

3. In an anchor device for use within a well casing, the combination of: tubular body means including a mandrel adapted to be lowered into the well casing, an elastomeric sleeve encircling said mandrel, a casing-engaging member disposed around said elastomeric sleeve and having a plurality of longitudinal slots defining a series of circumferentially adjacent gripping elements, a pair of retainer collars on the tubular body means clamping said member between them with freedom of the ends of said casing engaging member to move in the radial direction, means on said collars securing the ends of said elastomeric sleeve thereto, the tubular body means having a skirt, one of the collars being mounted for axial sliding movement relative to said tubular body means and having seal means slidably engaging said skirt, said one collar having a first surface means on one side of said seal means adjacent said casing-engaging member and a second surface means on the opposite side of said seal means remote from said casing-engaging member, said surface means being subject to fluid pressure for urging said one collar in said axial sliding movement relative to said tubular body, said second surface means being of greater area than said first surface means, whereby said one collar is urged toward said casing-engaging member by fluid pressure thereon, a series of circumferentially adjacent backing strips interposed between said elastomeric sleeve and said casingengaging member, said backing strips being staggered with respect to said gripping elements to bridge the slots and to prevent portions of said elastomeric sleeve from passing into said slots, and means establishing fluid communication between the interior of said mandrel and the interior therebetween and expansible means interconnecting said engaging elements, said engaging elements being radially movable between contracted and extended positions,

means for coupling said engaging elements to said mandrel in an axial load-supporting position yet permitting radial movement to said contracted and extended positions, said coupling means including means for contacting surfaces of said engaging elements at opposite ends of said engaging elements, and maintaining said contact under operating conditions of said device for confining said sleeve means and preventing extrusion outwardly thereof, backing means interposed between said sleeve means and engaging means so as to be disposed over said spaces to bridge the same in said contracted and extended positions, and means for establishing fluid communication to the interior of said sleeve means for application of pressure to said sleeve means.

5. A well tool for use in a well conduit comprising: a body member; anchoring means on said body member including conduit-engaging means movable relative to said body member between a retracted position and an expanded position where said body member is held relative to a well bore conduit against movement axially thereof, said anchoring means including an expansible sleeve member for actuating said conduit-engaging means, said body member having upper and lower cooperative abutment means adapted for engagement with the adjacent ends of said conduit-engaging means and pressure-responsive means for bringing said upper and lower abutment means into engagement with said ends.

6. In an anchor device for use within a well casing, the combination of: tubular body means having first and second oppositely directed abutment means thereon spaced apart longitudinally and facing one another, pressureresponsive means on said body means between said spaced abutment means comprising an elastomeric sleeve encircling said body means, laterally extensible casing-engaging means including circumferentially arranged longitudinally extending gripping elements around said body means, said casing-engaging means having first and second opposed abutment surfaces thereon, respectively, facing an adjacent one of said abutment means, sleeve-supporting means including circumferentially arranged longitudinally extending backing strips between said sleeve and casingengaging means and circumferentially offset relative to said gripping elements to bring each of said backing strips, respectively, into operative relationship to an adjacent pair of said gripping elements, and means for transmitting axial loads on said body means to said casing-engaging means including first and second members, respectively, slidably mounted on said body means above and below said casing-engaging means between said abutment means and abutment surfaces for engagement therewith; and means establishing fluid communication between the interior of said body means and the interior of said sleeve, whereby fluid under pressure may expand said elastomeric sleeve and backing strips radially to extend said casingengaging means outwardly into engagement with the easing, at least one of said members having an area responsive to pressure from fluid applied to said sleeve for urging said one member inwardly against the adjacent abutment surface of said casing-engaging means for substantially eliminating clearance between said one member and said' abutment surface through which said sleeve could extrude.

7. An anchor device for use within a Well casing comprising a body adapted to be lowered into a well casing,

an expansible sleeve circumscribing said body,

said body having passage means for receiving pressurized fluid,

said passage means communicating with the interior of said sleeve for providing an outwardly directed force on said sleeve by said pressurized fluid upon receipt of such pressurized fluid by said passage means of said body,

a casing-engaging means around said sleeve,

said casing-engaging means being expansible outwardly in response to a force thereon received from said sleeve as a result of the application of said pressurized fluid to the interior of said said sleeve,

said casing-engaging means having exterior surface portions for engagement with the interior of a Well casing upon such expansion of said casingengaging means,

positioning means adjacent either end of said casingengaging means for positioning said casing-engaging means longitudinally of said body,

and pressure-responsive means having a surface acted upon by fluid pressure, said pressure-responsive 10 means being associated with said casing-engaging means for substantially eliminating any clearance between said positioning means and said casing-engaging means upon'application of fluid pressure to said body and said outward expansion of said casing-engaging means irrespective of longitudinal elongation of said body. 8. A device as recited in claim 7 in which said casingengaging means includes for said exterior surface portions a plurality of substantially longitudinally extending elongated segments,

each segment having a first outer surface portion substantially parallel to the axis of said body for initially engaging the interior of a Well casing upon said expansion of said casing-engaging means, and at least one second outer surface portion longitudinally outwardly of said first surface portion intersecting said first surface portion at a relatively shallow obtuse angle,

said segments being bendable about the intersection of said surface portions in response to fluid pressure applied thereto through said sleeve, each of said segments having an inner corner at the end of said second surface portion,

said corners being pivoted through an are upon such bending whereby said second surface portions approach alignment with said first surface portions upon said bending and and the lengths of said segments are increased in the direction of said axis of said said mandrel, said positioning means including a shoulder on said body at either end of said casing-engaging means for engagement with said segments,

said segments upon said bending maintaining said engagement as a result of the elongation thereof for thereby providing said means for eliminating clearance upon said longitudinal elongation of said body. 9. An anchor device for use within a well casing comprising a body adapted to be lowered into a well casing, an expansible sleeve circumscribing said body,

said body having passage means for receiving pressurized fluid,

said passage means communicating with the interior of said sleeve for providing an outwardly directed force on said sleeve by said pressurized fluid upon receipt of such pressurized fluid by said passage means of said body, an assembly around said sleeve,

said assembly including a casing-engaging means expansible outwardly in response to a force thereon received from said sleeve as a result of the application of said pressurized fluid to the interior of said sleeve,

said casing-engaging means having exterior surface portions for engagement with the interior of a well casing upon such expansion of said casing-engaging means, each end portion of said assembly including an assembly abutment, said body including a body abutment adjacent each of said assembly abutments for cooperation with said assembly abutments to position said assembly longitudinally of said body and transmit loads from said assembly to said body, and pressure-responsive means associated with said assembly for preventing substantially any clearance between adjacent abutments of said body and said assembly when said casing-engaging means is expanded outwardly by said sleeve irrespective of longitudinal elongation of said body. 10. An anchor device for use within a well casing comprising a tubular mandrel adapted to be lowered into ,a Well casing, an expansible sleeve circumscribing said mandrel,

said mandrel having passage means from the interior to the exterior thereof within said expansible sleeve,,

whereby pressurized fluid from said mandrel communicates with the interior of said expansible sleeve for expanding said expansible sleeve, a segmented element circumscribing said expansible sleeve,

said segmented element being expansible by said expansible sleeve upon the application of fluid pressure from'said mandrel to the interior of said expansible sleeve, said segmented element having exterior surface portions for engagement with the interior of a well'casing upon such expansion for gripping said well casing and iesistingaxial movement of said segmented element relative to said casing,

and means providing an outwardly extending shoulder at either end of said segmented element for positioning said segmented element longitudinally of said mandrel,

at least one of said shoulders being provided by an annular axially movable member circurn-t scribing said mandrel axially outwardly of one end of said segmented element, said annular member having pressure area means responsive to fluid pressure on the interior of terior to the exterior thereof within said expansible sleeve,

whereby pressurized fluid from said mandrel communicates with the interior of said expansible sleeve for expanding said expansible sleeve,

a segmented element circumscribing said expansible sleeve,

said segmented element being expansible-by said expansible sleeve upon the application of fluid pressure from said mandrel to the interior of said expansible sleeve,

said segmented element having exterior surface portions for engagement with the interior of a well casing upon such expansion thereof for gripping said well casing and resisting axial movement'of said segmented element relative to said casing,

means providing an outwardly extending shoulder at either end of said segmented element'for positioning 1 said segmented element longitudinally of said mandrel,

at least one of said shoulders being provided by an axially .movable annular'member circum:

scribing said mandrel axially outwardly of one end of said segmented element,

said annular member having an outwardly facing circumferential surface,

said mandrel having an inwardly facing circumferential surface overlapping said circumferential surface. of said annular member,

a seal for preventing the passage of fluid between said circumferential surfaces, and passage means for permitting fluid pressure on the interior of said sleeve to be applied to said annular member outwardly of said one end of said segmented element,

whereby said fluid pressure is contained by said seal and said annular member provides a pressure area so that said fluid pressure produces a reaction on said annular member forcing said annular member against said one end of said segmented element.

12. An anchor device for use within a well casing comprising a tubular mandrel adapted to be lowered into a well casing,

an expansible sleeve circumscribing said mandrel,

said mandrel having passage means from the interior to the exterior thereof within said expansible sleeve,

said segmented element being expansible by said expansible sleeve upon the application of fluid pressure from said mandrel to the interior of said expansible sleeve, said segmented element having exterior surface portions for engagement with the interior of a well casing upon such expansion thereof for gripping said well casing and resisting axial movement of said segmented element relative to said casing, and means providing an outwardly extending shoulder at either end of said segmented element for positioning said segmented element longitudinally of said mandrel,

at least one of said shoulders being provided by an axially movable annular member circumscribing said mandrel axially outwardly of one end of said segmented element,

said annular member having an annular inner shoulder, said mandrel having an annular fixed shoulder in opposed relationship with said shoulder of said annular member, said sleeve having an annular rib interposed between said shoulders of said annular member and said mandrel,

whereby said fluid pressure on said sleeve reacts through said rib for exerting an axially inwardly directed force on said annular member relative to said segmented element for forcing said annular member against said 'one end of said segmented element. 13. A device as recited in claim 12 in which said adjacent shoulders of said annular member and said mandrel are inclined so as to be convergent outwardly in the radial direction,

said rib of said sleeve being complementarily received in the space between said adjacent shoulders.

14. An anchor device for use within a well casing comprising: a body; an expansible sleeve encircling said body and fluidly sealed at its opposite ends thereto; inner and outer tubular members encircling said sleeve, each of said tubular members having a plurality of longitudinal slots 7 extending from opposite ends thereof and respectively terminating short of the other end thereof for making said tubular members radially expansible and defining interconnected circumferentially-spaced elements on each, said outer member having its said slots staggered in relation to said slots of said inner member for preventing portions of said sleeve from entering said slots of said outer member; means on said body engaging the opposite ends of said outer member for substantially preventing longitudinal movement thereof in relation to said body without preventing radial movement of its said ends; and means establishing fluid communication with the interior of said sleeve, whereby fluid under pressure may expand said sleeve and expand said tubular members outwardly to bring the outer surfaces of said elements of said outer member into engagement with a casing.

15. An anchor device for use in a well bore comprising: a mandrel having port means; expansible sleeve means fluidly sealed around said mandrel and port means; wallengaging means disposed over said sleeve means and arranged to move radially upon expansion and contraction of said sleeve means and including means completely enclosing said sleeve means, said wall-engaging means having exterior surfaces capable of engaging the wall of a well conduit in response to expansion of said sleeve means; and means for coupling said wall-engaging means on said mandrel for supporting longitudinal loading on said mandrel including abutment surfaces adjacent opposite end portions of said wall-engaging means, and pressure-responsive means urging at least one of said abutment surfaces against one of said adjacent end portions of said wall-engaging means for confining said sleeve means and preventing extrusion thereof between said one abutment surface and said adjacent one end portion.

'16. In an anchor device for use within a well casing, the combination of: a body member; an elastomeric sleeve encircling said member; casing-engaging means comprising circumferentially-spaced, longitudinally-extending gripping elements around said sleeve; means for mounting said gripping elements on said mandrel for preventing their movement axially relative to said mandrel while permitting said gripping elements to move in a radial direction, said gripping elements and mounting means having opposed surfaces arranged for abutting; pressure-responsive means for maintaining said opposed surfaces in abutment with one another for preventing extrusion of said elastomeric sleeve between said abutting surfaces; circumferentially-space-d, longitudinally-extending backing means disposed between said elastomeric sleeve and said gripping elements, said backing means being circumferentially staggered with respect to said gripping elements to enclose said elastorneric sleeve; and means establishing fluid communication between the interior of said mandrel and the interior of said elastomeric sleeve, whereby fluid under pressure within said mandrel may expand said elastomeric sleeve radially and cause it to expand said backing means and said gripping elements outwardly to engage said gripping elements with a casing.

17. An anchor device for use within a well casing comprising: a body having passage means and adapted to be lowered into a well casing; an expansible sleeve circumscribing said body, said passage means communicating with the intrior of said sleeve; casing-engaging means disposed about said sleeve, said casing-engaging means being extendible upon expansion of said sleeve for engagement with a well casing; means adjacent the ends of said casing-engaging means for supporting said casing-engaging means longitudinally on said body; and pressure-responsive means having a surface acted upon by fluid pressure, said pressure-responsive means including means for substantially eliminating clearance between said supporting means and said casing-engaging means upon application of fluid pressure through said passage means to the interior of said sleeve.

18. An anchor device for use within a well casing comprising: a body adapted to be lowered into a well casing; an expansible sleeve circumscribing said body; said body having passage means communicating with the interior of said sleeve; an assembly around said sleeve, said assembly including casing-engaging means extendible upon expansion of said sleeve for engagement with a well casing, each end portion of said assembly including an assembly abutment, said body including a body abutment adjacent each of said assembly abutments for cooperation with said assembly abutments to position said assembly longitudinally on said body and transmit axial loads from said body to said assembly; and pressure-responsive means for substantially preventing clearance between adjacent abutments of said body and said assembly when said casingengaging means are extended.

References Cited by the Examiner UNITED STATES PATENTS 1,343,273 6/1920 Moore 279-2 2,373,005 4/1945 Baker 166122 2,767,676 10/1956 Johnson et a1. 26948.1 2,970,651 2/1961 Roberts l66212 CHARLES E. OCONNELL, Primary Examiner.

.T. A. LEPPINK, Examiner.

Claims

4. AN ANCHOR DEVICE FOR USE IN A WELL BORE COMPRISING: A TUBULAR BODY MEANS INCLUDING A MANDREL ADAPTED TO BE LOWERED INTO A WELL BORE, SAID MANDREL BEING ADAPTED TO RECEIVE AN AXIAL LOAD IN EITHER DIRECTION, FLUID-TIGHT, PRESSURE-TRANSMITTING SLEEVE MEANS ENCIRCLING SAID MANDREL, LOAD-SUPPORTING, WELL BORE ENGAGING ELEMENTS CIRCUMFERENTIALLY DISPOSED ABOUT SAID SLEEVE MEANS WITH SPACES THEREBETWEEN AND EXPANSIBLE MEANS INTERCONNECTING SAID ENGAGING ELEMENTS, SAID ENGAGING ELEMENTS BEING RADIALLY MOVABLE BETWEEN CONTRACT AND EXTENDED POSITIONS, MEANS FOR COUPLING SAID ENGAGING ELEMENTS TO SAID MANDREL IN AN AXIAL LOAD-SUPPORTING POSITION YET PERMITTING RADIAL MOVEMENT TO SAID CONTRACTED AND EXTENDED POSITIONS, SAID COUPLING MEANS INCLUDING MEANS FOR CONTACTING SURFACES OF SAID ENGAGING ELEMENTS AT OPPOSITE ENDS OF SAID ENGAGING ELEMENTS, AND MAINTAINING SAID CONTACT UNDER OPERATING CONDITIONS OF SAID DEVICE FOR CONFINING SAID SLEEVE MEANS AND PREVENTING EXTRUSION OUTWARDLY THEREOF, BACKING MEANS INTERPOSED BETWEEN SAID SLEEVE MEANS AND ENGAGING MEANS SO AS TO BE DISPOSED OVER SAID SPACES TO