US2603294A

US2603294A - Well packer

Info

Publication number: US2603294A
Application number: US636543A
Authority: US
Inventors: Charles H Barnes
Original assignee: LANE WELIS Co
Current assignee: LANE WELIS Co; LANE-WELIS Co
Priority date: 1945-12-21
Filing date: 1945-12-21
Publication date: 1952-07-15
Anticipated expiration: 1969-07-15

Description

C. H. BARNES WELL PACKER Filed Dec. 21, 1945 5 Sheets-Sheet 1 ,n T. 55M 31W 2 NM m 1, Wj Am M @v A/ x l. V... .v B m 5 7 A a 5 5 M ,L7/ ,ff/M m; jy, Q @0D 00 N N L a C. H. BARNES Filed Deo. 2l, 1945 WELL PACKER i 3 SheebfLsheet 2 M INVENTOR ATTORNEY Filed DeC. 21, 1945 A 5 Sheets-Sheet 5 July 15, 1952 c. H. BARNES 2,603,294

WELL PACKER ATTORNEY Patented July 15, 1952 UNITE sr'igs grani* QFFICE WELL PACKER Charles H. Barnes, Glendale, Calif., assigner to Lane-Wells Company, Los Angeles, Calif., a

corporation of Delaware Application December 21, 1945, Serial No. 636,543

'7 Claims. l

This invention relates tol packing devices' for wells and finds its principal application and use packers and other types of well packer devicesv currently being used andV which employ resilient material, such as rubber, neoprene, and the like materials to pack-oli toA form iiuid type seals at any desired point in the well between twoconcentric casing strings or between a tubing and casing string, will not long withstand the severe temperature and pressure conditions usually encountered in the deep, high pressure oil wells now being drilled.

It has been foundv that the ability of the conventional packer to withstand high pressure differentials over a long period of time is dependent largely upon the hardness and the so-called cold flow resistance of the resilient packing element employed. When the resilient packing elements are sufficiently hard to render them capable of long life under the high temperature and pressure conditions encountered in the well, they are then usually so non-pliable or rigid as tobe impracticable of being set with reasonable packer expansion forces, while, on the other hand, if the packing elements are soft or pliable enough to be readily set, they are then susceptible to so-called cold flow or extrusion under high dii'erential pressures into and through the annular clearancesV between the inside surface of the casing and the outside surface of the packer body; Such extrusion eventually results in escape' of sufncient of the packing material to reduce the packing pressure upon the surrounding surfaces against which' it is intended to seal, to allow leakage with eventual cutting and channeling of the packing to the point of complete failure.

From the foregoing, it is seen to be obviously desirable to employ, and it is accordingly a prin cipal object of this invention to provide a packer device employing resilient packing elements which are suiiiciently soit, resilient and pliable to effect' the' satisfactory iiuid tight seal under moderate packer compression pressures, while, at the same time, preventing the undesirable dow and extrusion action usually associated with such desirable packer characteristics.

It is a further object of this invention to provide an improved sealing means to confine the packing and to prevent the extrusion of resilient packing material from the' packing elements, while under pressure, int'o the adjacent clearance spaces between the packer compression elements and the inside surface of the easing or pipe which the seal is to be maintained'.

AnotherV object `'of' this invention resides in improved means for releasing or breaking loose previously set packing elements from lsealing engagement, with a surrounding casing or pipe whereby the packer may readily be removed from withl the well, or, if desired, readily relocated and reset` ata new position within the well.

The yobjects of this invention are, broadly speaking, accomplished in anv embodiment of the invention comprising a resilient rubber-"like packing element or sleeve adapted to bev deformed by the application of longitudinal' pressure thereto sufficient to expand it radially into sealing engagement between the packer' and a surrounding casing' or pipe and with closure ring means provided in association with the packing' compres'- si'on means in such relation as 'to' close the clearance spaces at the end ci the packerv sleeve element between the packer and surrounding casing to prevent escape by extrusion or flowing action ofthe packingiwhile under pressure.

The embodiment of the invention also comprises mechanical means to release the packing element, and the rcompression andv packing retainer means, to break the packer element seal and to release the casing gripping means in proper sequence, whereby the previously set packer may be readily removed from its `pre" viously set position.

These and other objects, advantages, and feae tures of novelty will be evident' hereinafter.

In the drawings, which show by way of illus'- tration, .apreferred embodiment of the invention and in which like numerals designate the saine or' similar .parts ofv theV several views:

Figure 1'. is an elevational view,- in partial longitudinal section ofa packer embodying the apparatus of this invention, said packer being shown suspended in an unset position within a Well casing?.

Figure 2' is a partial elevational View, in partial longitudinal section of the packer of'Figure l set the well casing".

l Figure Bis an enlarged, detail View of the' packe ing compression and retainer mechanism.

Figure 4 is an endA view of the packing' retainer mechanismtaken on line 6 4 off Figure 3.

Figure 5 is an enlarged perspective view of a portion of the retainer'ring member ofthe comev pression and retainer mechanisniof Figure 3f Figure 6 is an enlarged fragmentary, detail view of a portion cf Figure 1.

Figure 7 is an enlarged fragmentary, detail view of a portion of Figure 2.

Referring now primarily to Figures 1 and 3 to 6, inclusive, I is a conventional packer head element which may be attached to and suspended in the Well by a suitable string of pipe or tubing and to which a conventional tubular mandrel I I may be threadedly coupled as shown at I2. The mandrel I I carriers a lower portion 23 of increased diameter forming an annular shoulder I3 which, when the packer is suspended in the Well in the unset condition as shown in Figure l, engages and supports the lower end of a cylindrical packing support or packer sleeve I4. On the upper end of the packer sleeve I4 and threadedly coupled thereto at I5 is an annular-shaped collar member I6 which serves as the lower half of a packer circulation by-pass valve having formed at its upper end an inwardly bevelled valve seat I1 adapted to receive, when in the closed position, a bevelled valve surface I8 formed on the lower end of the beforementioned packer head I9. The packer sleeve I4, and the collar I6 are spaced concentrically with respect to the mandrel II to form an intermediate, annular clearance space between the outside surface of the mandrel I I and the inside surface of the said packer sleeve I4, said concentric spacing being effected by means of a plurality of radial webs located at the upper and lower ends of the sleeve as shown at 2| and 22, respectively. When the packer is in the set position as shown in Figure 2, and as hereinafter more fully explained, the mating bevelled valve surfaces I1 and I8 of the collar seat and the tubing head are moved longitudinally and forced into sealing engagement with one another, thus acting as a valve to close the upper end of the beforementioned annular circulation space 20.

Supported below the mandrel seat or shoulder I3 and slidably positioned on the enlarged portion 23 of the mandrel II is a slip-expanding cone 25. The slip-expanding cone 25 makes threaded connection at 26 at its upper end with the lower end of a spool-shaped coupling or collar member 21 which, as best shown in Figure 3, carries at the upper end thereof a segmented packing retainer ring 28. This packing retainer ring 28 is composed of a plurality of step-wise-cut, overlapping, arcuate segments joined end to end circumferentially, with each such arcuate segment attached to the beforementioned sleeve 21 with limited freedom for radial expansive movement by means of a leaf spring as shown at 29.

In Figure 3 and elsewhere in the drawings, the expansible packing retainer ring 28 is illustrated as being 'composed of 4 identical circumferential or

arcuate segments

28a, 28h, 28e, and 28d, but obviously, any number of such arcuate segments may similarly be employed as best suited to. the diameter of the casing in which it is to be set, and the degree of perfection of the retaining action it is desired to attain.

The upper end of the sleeve 21 is provided at its outer edge with an upstanding annular lip 30, and the inner edges of the lower ends of the arcuate segments 28 of the packer retainer ring are formed with corresponding, downwardly extending interlocking, arcuate segmental tongues as shown at 3 I. Upon outward radial movement of the arcuate segments of the retainer ring 28 to increase the effective diameter of the retainer ring asl a whole, the segmental tongues 3I may be brought into limiting locking engagement with the beforementioned encircling lip 30.

The inside of the spool-shaped sleeve 21 is formed with a lower portion 42 of increased inside diameter to provide a shoulder 43 from which it may be supported upon a corresponding shoulder 44 on the lower end of the packer sleeve I4, as hereinafter described in connection with its operation.

The opposite upper ends of the segments of the ring 28 are formed with inwardly facing, downwardly converging, conical surfaces as shown at 38 around the inner edge thereof, terminating at an upper edge 32 by intersection with an outwardly facing cylindrical surface 4I. Each retainer ring segment 28a-28d is provided with an arcuate tongue 33 extending circumferentially from one side thereof and a step-shaped mating groove 36 extending circumferentially into the opposite side thereof and adapted to receive in circumferentially sliding fit the corresponding tongue of an adjacent retainer ring segment. The tongue of each segment, thus in turn, makes sliding t into the mating groove of its next adjacent segment in the series of circumferential segments thereby forming in effect an expansible ring having a plurality of overlapping step-cut segments which remain in sealing contact with one another. Upon expansion, the overlapping elements of the segments slide upon one another to permit an increase in effective circumference and diameter of the ring.

Referring again primarily to Figure 3, a packer compression ring is shown at 34, carried on the top of and in sliding engagement with the upper conical end surfaces 38 of the plurality of segments of the retainer ring 28. As thus shown in Figure 3, the packing compression ring 34 is formed with an outwardly diverging, frusto conical bearing surface as shown at 31 which is adapted to fit and to contact in sliding relationship with the before described correspondingly bevelled upper end surfaces 38 of the beforementioned segments of the packing retainer ring 28. The ring 34 is provided, adjacent the conical surface 31, with an encircling annular lip 39, separated from the beforementioned bevelled surface 31 by an intervening annular spacing groove 4U. Upon the application of longitudinal force through the ring 34 to the segments of the retainer ring 28, the resultantly induced sliding and wedging action between the mutually contacting

conical surfaces

31 and 38 will result in radial forces causing the segments 28a-28d of the retainer ring 28 to move radially outward against the resistance of the leaf springs 29. The compression ring 34, together with the expansible retainer ring 28 thus together serve to close the annular space between the packer sleeve and a surrounding casing in the manner shown in Figures 2 and 7. As a limiting condition, in the absence of a surrounding casing or in case the casing is too large, the beforementioned outer cylindrical faces 4I on the ends of the segments of the retainer ring 218 opposite the bevelled surfaces 38 may, by the application of longitudinal force therethrough, be brought into restraining contact with the inside surface of the lip 39 and to a position Within the annular recess 48 of the compression ring substantially as illustrated in Figure 7. The relative position of the lips 30 and 39 and the tongues 3I and surfaces 4I, respectively, at the lower and upper ends of the retainer ring segments are then such that unless otherwise restrained, such as by contacting a surrounding casing, as beforementioned, the maximum outwardly expansive movement of the a slip cage 48.

'eginents thereby the maximum diameter of the -sealingl'ring 28 are thereby limited.

' Referring again primarily to Figure 1, the packer sleeve I4 is provided with another annular shoulder 54, located a short distance above the beforementioned shoulder 44, and formed by a slight reduction in diameter in the upper portion of the said packer sleeve I4. The shoulder 54 isadapted to contact the inner lower surface 'of the packing compression'ring 34 at 55 and is located at such a distance above the 'shoulder '43 as to support the said compression ring 34 and remove axial forces from the retainer ring 28 when the packer assembly is hanging in the unset condition as shownin Figure 1.

A resilient, expansible packing 35 is carried on the packer sleeve I4 between a pair of oppositely facing

packing compression rings

34 and 34a, ring 34a being of the same or similar form to that of ring 34 hereinbe'fore described.

On the end portions of the packer sleeve I4 and adjacent the outer faces of the

compression rings

34 and 34a are segmental retainer rings 2 3 and 23', retainer ring 25 being also of the 'same construction as ring 28 hereinbefore ldescribed.

The circulation valve sleeve I terminates at its -lower end adjacent the threaded connection I5, in the same form as that shown for the upper end of the retainer ring supporting spool 2l and f carries a'plurality of leaf springs 29a, similar to those shown at 29 for holding the segments of the retainer ring 28' in assembled position.

Slidably supported on the outer truste-conical surface of the slip-wedging cone 25, are aV plu` rality of conventional, wickered slips, as shown at 45. The wickered slips are supported in the usual manner by means of flexible reins '46 which extend between the'slips 45 and a collar 41 of The slip cage 48 comprises a tubular sleeve 49 terminating at its upper ends in the collar 41 and having a separate lower collar 50, the whole being slidably supported upon the lower portion of the mandrel II. A p lurality of 'outwardly bowed cage springs extend between and resiliently interconnect the slip-cage collars 4l and 50 as shown at 5I and these springs 5I are adapted to make sliding frictional contact'with the inside surface of a well casing. A

J slot 52 of usual design is provided through the wall of the cage sleeve 49 and is adapted to make sliding and limited rotational nt with a screw or pin 53 extending into the J slot from the Vtubing mandrel II. As illustrated. in Figure 1, the slip cage 48 is initially locked by means 4ofthe screw 53 in the upper end of the J slot 52 intheposition which retains the slips 45 in their retracted positions relative to the slip cone 25. `Vi'l'iile conventional cone and slips means for enlfgaginga casing is herein illustrated, any other suitable casing engaging means may be'employed Ywhich will perform the same function.

The resilient packing may be of any suitabletype, such as for example, a single annular 'or sleeve-shaped member ci suitable size or as fof the invention, its operation is asfollows:

lhorizontal portion of the J slot 52.

VReferringr rst primarily .fito lFigureil, dane packer device is viirst lowered by=ineans .ofpiping or tubing or 'the like suitable .means iinto the well 'to a position .within the Vwell casing at which it is desired to .fset vthe packer. During the lowering -and ju'st Yprior to setting, the several 'parts of the packer uassembly -will occupy the "relative positions illustrated in Figure l. During "the lowering of the packer in Vthe casing, `the lower packing ycompression .ring '34 `and the resilient packing 35 'and upper compression ring 434a carried by it are initially vsupported upon 'the fannular'shoulder .54 ofthe packer sleeve If4,;the slip .cone T25 and lspool 27 hang 'suspended lwith thein'ner .annular shoulder '43 of the :spool *,ele-

nient 121 fbearing lupon the shoulder 44 'of 'th'e .lower end-'of the packer sleeve Ipacker sleeve .I5 is, in turn, .'supportedat `the I4, Vand the lower 'end uponthe vshoulder I3 on th'emandrel 23. The resilient packingt and the packing `retainer'rin'gs .28 and P23 vare thus relieved of any substantial .longitudinal weight forlfor'c'e which'would tend to expand them intoycontact lwith ra surrounding casing during the lowering 'the easing'to the point at'which it is desiredto set the packer, the supporting tubing and the mandrel II` connected therewith is given a slight, left-hand 'rotation through an angle sufficient -to carry the pin 53 across the horizontal top portion of the J slot from the position shown in Figure 1 to a position at the .top of the longitudinally extending arm of the J slot. rubing ID and mandrel Il are then again lowered and by reason of the frictional engagement of the cage springs 5I `with the inside surface of the casing, the slips 45 are carried upward relative to the slip cone 25 into wedging engagement between the slip cone and the inside surface of the surrounding casing as shown in Figure 2.

Further fdownward'motion of the tubing and the mandrel -II afterthus setting the slips, resuits in 'first lowering the shoulder 44 of the packer sleeve away from the shoulder 43 of the spool member 21, thus transferring the weight of the expansible retainer ring 28, member 21, and cone v25 to the slips 45. Next, with continued downward motion of the mandrel Il and packer sleeve I4, the shoulder 54 of the packer sleeve is lowered away from the lower surface of the compression vring 34, thus transferring the weight of the compression ring 34a, packing body 35 and compression ring 34 to the expansible'retainer rin'g28 which is, in turn, supported through spool member 21' by the "cone 25 and slips 45. Next, with still further continued downward travelof the mandrel II, the lshoulder I3of 'the mandrel II will be Vlowered awayfromVsupporting contact'with the lower end of lthe packer sleeve I4 thus transferring the weight of the packer sleeve I4, and collar Itr through the upperv expansible retainer ring 28'f'to 'the compression ring 24a Vand thence fthrough the packingbody-35 tov-the lower compression ring 34, lower expansible retainer ring 28 and thence on to the slips 45 as before described. Finally, further downward motion of the mandrel carries the bevelled surfaces I8 and I1 of the mandrel head I0 and collar I6, resp'ectively, into closed contact as shown in Figure 2, after which continued downward pressure applied to the mandrel I I from the tubing transmits longitudinal compressive force and motion through the sleeve I6 to the segmental retainer ring 28 and thence through the mutually contacting

conical surfaces

31a and 38a to the packer compression ring 34a. The force thus applied to compression ring 34a is transmitted longitudinally through the packing body 35 to the opposite compression ring 34 through the segmental retainer ring 28, through the spool member 21 and slip cone 25 to the slips which, as before stated, are in wedging engagement with the inside surface of the casing.

The force thus applied to the segmental retainer rings 28 and 28 causes the segments thereof, to slide outwardly radially over the conical surfaces of contact with the compression rings 34 and 34a, respectively, until they are brought into engagement with the inside surface of a casing as shown in Figure 2.

In the completely set condition, thepacking retainer rings 28 and 28' are shown thus expanded into closing engagement with the yinside surface of a casing and by reason ofthe internal pressure, a portion of the packing may be caused to flow longitudinally into the annular clearance space between the packer compression rings 34 and 34a and the inside surface of the casing until it is stopped by the closing or retaining action of the overlapping segments of the expandable retainer rings 28 and 28' as best shown in Figure 7.

For clarity and convenience in the drawings,

only the initial stage of the longitudinal flow of the packing material 35 between the compression rings 34 and 34a and the surrounding casing toward the retainer rings 28 and 28 is illustrated `In Figure 2. A more complete flow condition is illustrated in Figure 7.

Longitudinal flow-by and loss of packing material is thus checked and prevented by the confining action of the sealing rings 28 and 28'. One of the advantageous features of the construction of this packer resides in the positiveness and facility with which it can be broken loose from packing engagement with a surrounding casing in a well and freely moved for resetting or withdrawal from the well without the difficulties usually encountered with conventional packers under such conditions. After having been set as shown and illustrated in Figure 2, the packer may be released from the set condition by elevating the tubing and the mandrel II and when this is done the free release of the packer from the casing is accomplished by and is the result of the following consecutive steps. First, the valve I'I--I 8 is opened by the upward movementof the packer head I and the mandrel IfI relative to the collar member I6, after which the shoulder I3 of the mandrel 23 is carried upward` into engagement with the lower end of 'thepacker sleeve I4, thereby lifting the packer sleeve I4 carrying the valve sleeve I6 and retainer` ring 28 off the top of the compression ring 34a 'and' packing 35, thusrelieving a large portion of the longitudinal expansive pressure on the packing rings 35j and expansible retainer ring 28.V Next, upon further upward motion of the mandrel I I, the shoulder 54 is carried upward into supporting engagement with the lower surfaceA 55 of the compression ring 34, thus removing all of the longitudinal loading from the lower expansible retainer ring 28 permitting it to contract fully from contact with the surrounding casing. Continued movement applies suin'cient upward force through the ring 34 to the packing 35 to break it loose from the inside surface of the casing and to allow it to contract to its approximate original diameter as shown in Figure 1. Next, upon still further upward movement of the mandrel I I, the shoulder 44 of the packer sleeve I4 is finally carried upward into engagement with the shoulder 43 on the inside of the spool member 26, which, in turn, lifts the slip cone 25 upward free of the slips 45, after which the Whole packer assembly, again supported from the mandrel as shown in Figure 1, may be elevated freely in the casing and removed from the well. If, however, it is desired to reset the packer at a lower position in the casing, the tubing and the mandrel suspended therefrom is given a slight, right-hand rotation while it is being elevated, sufcient to move the pin 53 into latching position in the left-hand end 0f the upper horizontal arm of the J slot 52, as shown in Figure l, after which the whole packer may then again be lowered freely through the casing to the desired resetting position without carrying the slips 45 into wedging engagement between the slip cone 25 and the inside surface of the surrounding casing. Upon thus lowering or raising the packer to the desired new position, it can be reset in the saine manner as hereinbefcre described in connection with the original setting operations.

The action of the packing retainer rings 28 and 28', as hereinbefore described, are such as substantially to close oi the annular space between the packer sleeve I4 and the inside surface of the surrounding casing at the ends of the packer to form in effect, a closed annular chember containing the resilient packing material. Upon application of longitudinal compressive force to the retainer rings 28 and 28 and to the packing material therebetween, the packing material is subject, in effect, to a hydraulic pressure which causes it to be expanded radially and to ow both radially and longitudinally into intimate contact between the packer sleeve I4 and the inside surface of the surrounding casing. End-wise flow with resultant extrusion or leakage of the packing material which is thus, in effect, subject to hydraulic pressure, is prevented by the obstructing action of the overlapping segments of the expanded retainer rings 28 and 28.

The packing material being thus, in effect, confined within a fluid tight annular chamber at the time of its compression, may be composed of a relatively soft and. pliable rubber-like material which would, otherwise, be too soft to be retained in proper sealing engagement with the casing. The packing material thus confined may also be subject to temperatures which are substantially in excess of those herebefore possible and which have the effect of softening the packing material.

To prevent hailing action during raising or lowering operations of the packer in a well-containing fluid prior to setting or after releasing from a set position, provision is made for free flow through the packer by way of the flow channel comprising the valve I'I-I8, circulation passage 28 between the mandrel II and packer sleeve I4 and the annular space between the inner bore of the slip' expander cone 25 and the mandrel II.

vSuch construction as this, making provision for other parts of the packer to be constructed withV minimum clearances inside the casing in which it is to be employed, and yet permit rapid movement of the packer through a fluid-filled well bore hole or casing. Such minimum clearances reduce the radial travel and degree of expansion required in '.20

the expansible retainer rings which results in their better mechanical construction and increased eifectiveness of operation.

Such minimum clearances thus permitted, also are reflected in reduced part sizes and reduced ranges of motion of the various parts of the packer required for the setting or releasing operations.

It is to be understood that the foregoing is illustrative of but one apparatus, and that the invention is not limited thereby, but may include various modifications and changes made by those skilled in the art without departing from the spirit and scope of the invention as dei-ined in the appended claims.

I claim:

l. In a well packer, in which an annular shaped, resilient packing element is mounted on a packer body and is expanded by longitudinal compressive force to form a seal between said packer body and a surrounding casing, an expansible packing retainer means on said packer body adjacent one end of said packing element between said body and a surrounding casing and operative to prevent longitudinal ilow of said packing element when under compressive force, said packing retainer means comprising: a plurality of rigid, arcuate segments positioned substantially end to end; a circuniferentially extending tongue on each of said segments; a circumferentially extending recess on each of said segments, the

tongue of each segment being positioned in the recess of the next adjacent segment in overlapping sliding engagement with one another to form a circumferentially variable, radially expansible, segmented ring structure; a collar member positioned on said packer body substantially coaxial with said segmented ring structure; individual resilient means joining each of said arcuate segments coaxially to and adjacent one end of said collar member, said individual arcuate segments being thus adapted to be substantially longitudinally immovable but with freedom for radial motion adjacent an end surface of said collar member; a coaxial truste-conical bearing surface on an inner portion of said segmented ring structure; a second ring slidably encircling the packer body next adjacent said packing element and having a truste-conical wedging surface on an outer portion thereof in sliding wedging enigagement with said 'truste-conical bearing surface on said segmentedring and operable to simultaneously move all said segments radially outward upon application of longitudinal force through said second ring to said segments.

2. In a well packer apparatus according to `.claim '1 in which the said individual resilient means joining each of said arcuate segments to the collar member comprises a longitudinally directed flexible leaf spring.

'3. In a well packer, apparatus according to claim 1 'in which means are provided on said arcuate segments engageab-le with means on said ring and on said collar to limit the radial movement of said segments and thus to determine a maximum diameter of said segmented retainer ring structure.

4. In a Well packer, in which an annular shaped, resilient packing element is mounted on a packer body and is expanded by longitudinal compressive force to form a seal between said packer body and a surrounding casing, an expansible packing retainer means on said packer body .adjacent an end oi said packing element between said'body and a surrounding casing and operative to prevent longitudinal dow of said packing element when under compressive `force, said packing retainer means comprising: a plurality vof arcuate segments positioned substantially end to end with portions thereof in overlapping sliding engagement with one another to form a continuous, circumferentially variable, radially expansible segmented ring structure; a collar member positioned on the packer body substantially coaxial with said segmented ring structure; individual resilient means attached to each of said arcuate segments and joining them coaxially to an adjacent end of said collar member, said individual arcuate segments being thus adapted to be individually supported with freedom for radial motion at the end surface of said collar member; and a frusto-conical Wedge means slidable on said body next adjacent said packing element and slidably engaging said arcuate segments and operable to simultaneously move all said segments radially outward upon application of longitudinal force through said frusto-conical wedge means and said segmented ring structure.

5. In a well packer, in which an annular shaped, resilient packing element is mounted on a packer body member and is expanded by longitudinal compressive force to form a seal between said packer body member and a surrounding casing, an expansible packing retainer means on said packer body member adjacent an end of said packing element between said body member and a surrounding casing and operative to prevent longitudinal flow of said packing element when under compressive force, said packing retainer means comprising: a plurality of arcuate segments positioned substantially in end to end overlapping, circumferentially sliding engagement with one another to form a circumferentially variable, radially expansible segmented ring structure encirling said packer body member; a collar member positioned on said body member substantially coaxial with and adjacent to said segmented ring structure; resilient means joining said arcuate segments coaxially to said collar member, said individual arcuate segments being thus supported With freedom for limited radial motion on one end of said collar member; and annular means slidable on said body next adjacent said packing element and slidably engaging said arcuate segments and operable to simultaneously move all said segments radially outward upon application of longitudinal force therethrough.

6. In a well packer, the combination comprising: a cylindrical support; a pliable, annular packing element on said support; a circumferentially expansible packing retainer means encircling said support; a compression ring encircling said support intermediate said expansible retainer means and one end of said packing element; coengaging inclined surfaces formed on said retainer means and said compression ring to expand said expansible retainer means upon application of longitudinal compressive force therethrough; a slip-expanding cone member slidably mounted on said support beyond said retainer means and said compression ring from said one end of said packing element, said cone member having a surface for engagement with said packing retainer means; a slip slidable on said cone member between a nonwedging and a wedging position between said cone member and a surrounding casing; and packer setting means carried by said support to compress said packing element longitudinally on said support to expand said packing element and 20 said packer retaining means radially between said support and a surrounding casing after said slip is in wedging position between said cone member and a surrounding casing.

12 7. Apparatus as dened in claim 6 having a. second -compression ring and a second packing retainer means at the opposite end of said packing element from said cone member, said second packing retainer means having a surface for engagement with said packer setting means.

CHARLES H. BARNES.

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

UNITED STATES PATENTS Number Name Date 1,992,933 Baker et al. Mar. 5, 1935 2,005,955 Renouf June 25, 1935 2,058,103 Phipps Oct. 20, 1936 2,204,648 Baker June 18, 1940 2,241,532 Barnes May 13, 1941 2,241,561 Spencer May 13, 1941 2,295,770 Baker Sept. 15, 1942 2,368,928 King Feb. 6, 1945