US2972381A

US2972381A - Well packer

Info

Publication number: US2972381A
Application number: US642487A
Authority: US
Inventors: Raulins George Max
Original assignee: Otis Engineering Corp
Current assignee: Otis Engineering Corp
Priority date: 1957-02-26
Filing date: 1957-02-26
Publication date: 1961-02-21
Anticipated expiration: 1978-02-21

Description

Feb. 2l, 1961 G. M. RAULlNs 2,972,381

WELL PACKER Filed Feb. 26, 1957 4 Sheets-Sheet 1 Feb. 21, 1961 G. M. RAULlNs 2,972,381

WELL. PACKER Filed Feb. 26, 1957 4 Sheets-Sheet 2 ATTORNEY Feb. 21, 1961 G. M. RAULlNs 2,972,381

f v WELL PACKER Filed Feb. 2e, 1957 4 sheets-sheet s Fig. IO INVENTOR George Max Raulins @www Fi g. 8 ATTORNEY Feb. 2l, 1961 Filed Feb. 26, 195'? Fig.||

Fig. l2

G. M. RAULINS WELL PACKER 4 Sheets-Sheet 4 Fig. I3

George Max Roulns @www ATTORNEY of the packer may be dislodged or removed. y Y

nited States Patent@ WELL PACKER George Max Raulins, Dallas, Tex., assignor to Engineering Corporation, Dallas, Tex., a corporation of Texas Filed Feb. 26, 1957, Ser.v No. 642,487

z1 claims. (cl. 16e-12s) Still another object is to provide a packer hold-down having a sealing nipple which is movably connected in a tubing string and is engageable with a-packer mandrel selectively mountable in a selected position in the casing.

A further object is to provide a packer hold-down, of

the type described, which permits relative movement of the seal nipple with respect -to other elements ofV the packer by variations in pump pressure whereby foreign particles between the hold-down and the other elements A still further object is to provide a packer hold-down, of the type described, having a collet memberengageable in a recess of the packer,vfor locking the seal nipple against upward movement with respect tothe packer.

Another object of the uventionis to provide a packer hold-down, of the type described, wherein the pressure i diierential across the seal nipple tending to move the seal nipple upwardly causes the hold-down collet member to lock in the packer recess and arrest such upward movement of the seal nipple.

Still another object is to provide a packer hold-down, of the type described, which operates only when an upward pressure differential exists across the seal nipple.

A further object of the invention is to provide a packer hold-down whose effectiveness does not depend on the weight of the tubing resting on the packer.

A still further object of the invention is to provide a packer hold-down having a connecting means for selectively locking the packer hold-down to the packer which is simple in construction and operation. ,Y Y

Still another object of the invention is to provide a packer hold-down in which the hold-down is locked to the packer upon longitudinal movement ina Vselected direction of the tubing to which the hold-down is connected. f Y t s An additional important object of the invention is to provide a packer hold-down and sealing nipple assembly wherein the pressure of the iluids Within the well' acting upon the hold-down serves to restrain said hold-down in locked position; and, in one case the fluid pressure may be that in the Well bore above the packer acting exteriorly on the hold-down, and in another case the uid pressure may be that in the ow conductor acting interiorly onthe hold-down. Y

Additional objects and advantages of the invention will be readily apparent from the reading of the following description of a device constructed -in accordancejwith the invention, and reference to the accompanying drawings thereof, wherein:

Figure .1 is a view, partly in elevation and partly in election, of Aa tubing string in a well casing showing ,a pair 2,972,381 Patented Feb. 2l, 1961 ICC of packers locked in the casing, the tubing string being provided with hold-downs which are shown in engagement in the packers;

Figure 2 is a view, partly in elevation and partly in l section, showing a tubing string having a hold-down in a packer with the seal nipple in its lower position wherein the hold-down is not locked to the packer.

Figure 3 is a view, partly in elevation and partly in section, of the tubing string of Figure 2 showing fluid pressure acting on the seal nipple to hold said seal nipple in its upper position whereby the hold-down is locked to the packer.

Figure 4 is a View, partly in elevation and partly in section, of the tubing string showing the relation of the hold-down to the seal nipple as the tubing string is moved upwardly out of its operative engagement with the packer.

Figure 5 is a sectional view taken on line 5-5 of Figure 2;

Figure 6 is va sectional view taken on line 6 6 of Figure 2; v

Figure 7 is a sectional view taken on line 7-7 of Figure 3;

Figures 8 and 9 are views, partly in elevation and partly in section, showing a modified form of packer holddown and seal nipple and packer on a tubing string as they appear while being lowered into place in the casing;

Figure 10 is a view, partly in elevation and partly in section, showing the assembly of Figures 8 and 9 in position inthe casing with the hold-down and seal Vnipple locked in the packer; Y f

s Figure 11 is a fragmentary vertical sectional view showing a further modification of a packer hold-down andr seal nipple installed and locked inv a packer inv position in the casing; 'c

Figure 12 is a view similar to Figure 11, showing the hold-down being removed from the packer in the casing;

Figure 13 is a fragmentary vertical sectional view of still another modification of a packer hold-down and seal nipple installed and locked in a packer in a well casing;

Figure 14 is a view similar to Figure 13, showing the hold-down being removed from locked position in the packer; and

Figure 15 is a fragmentary vertical sectional view of a still further modification of the hold-down of Figure 13, and showing the hold-down locked inra packer.

Referring now particularly to Figure l of the drawings, Vth-e casing 10 of a well is shown provided with a'pair of landing nipples 11 connected therein at desired spaced locations in the well and forming portions of said casing. The landing nipples are each provided with stop and locking groove means comprising a pair of internal grooves or

recesses

12 and 13 which are adapted to receive the stop `and lock

bosses

14 and 15 of the collet members 16 of the packers 17. The bosses engage in the recesses of a selected landing nipple to stop the packer againstl further downward movement in thevcasing, and, as will be hereinafter more fully explained, to lock the packer against upward movement in the casing.l The upper grooves 12 of the two landing nipples areof different longitudinal Widths, the landing nipple 11 having the groove 12 of the greater width being connected in the casing below the other landing nipple so that the lower packer 1,7 will pass through the upper landing nipple during its downward movement, its upper bosses bridging the upper groove 12 of the upper landing nipple since said bosses are of greater length than the longitudinal width of the upper groove of said upper landing nipple. When the lower packer 17, however,'reaches the lower landing nipple, its collet bosses will enter the grooves of the lower landing nipple; and Vthe downwardly facing abrupt shoulders 18 at the lower ends. of the upper collet `bosses thereof will engage the corresponding upwardly facing abrupt stop shoulder 19 at the lower end of the upper groove 12 and thus stop further downward movement of the packer in the casing.

The packers 17 may be lowered individually into the casing by means of a suitable running tool; or, they may be releasably connected to the tubing by means of shearable screws 19a threaded inwardly through the wall of the upper mandrel section 21 of the packer into an external annular recess 44a in the lower sealing nipple section 44. The shearable screws are sheared after downward movement of the packer in the casing stopped by the engagement of the bosses o-f the collet member i6 in the grooves of their respective landing nipples. It will be apparent that by proper selection of properly dimensioned upper collet bosses 14, a particular packer 17 may be positioned in any one of a plurality of landing nipples l1 connected inthe casing, so that the packer may be selectively positioned in any one of several positions or locations in the casing. i

The packers 17 include a packer mandrel 2li having an upper section 2.1 into whose lower end is threaded a packing mandrel or section 22. The packing mandrel has a tubular skirt 26 secured to its lower end, as by welding at 27. The skirt has its bore enlarged at its upper end to provide an internal annular recess 26a therein, and an external annular flange 25 at the upper end ofthe collet member 16 is conlined in such recess. The sizes of the liange and recess are such the collet member may undergo a limited longitudinal movement relative to the skirt for a purpose which will be hereinafter more fully explained. The collet member has a plurality of depending resilient lingers '23 Vto whose lower ends are secured, as by welding, keys or lugs 24 having the bosses 314 and l formed thereon. The tubular skirt i'surroundsthe collet lingers 23 above the keys or Vlugs 24,arid`tl1`c lower end of said sleev'e'is thus normally positioned closely adjacent but spaced'slightly abovelthe upper ends of said lugs for a purpose to be hereinafter more fully explained.

The packer isl provided with a packing 30, which may beof the chevron type, which is disposed about the exterior of the packing mandrel between the lower end of the uppermandrel section 2l 'and an upwardly facing external `annular shoulder 3l on the lowerpend of the packing mandrel and thus seals between the landing nipple l1 and the packing lmandrel of the packer.

The upper mandrel section 'Zlhas an internal ilange 33 formed in the upper end of its bore to provide a downwardly facing shoulder which may be engaged by suitable running or retrieving tools. The bo-re of the upper mandrel section is reduced below the flange to form an upwardly facing beveled stop shoulder 34 whose purpose will be hereinafter described. rlhe reduced portion of the bore of the upper mandrel section Vis also provided with an internal annular groove or locking recess 35, spaced below the stop shoulder 3d, whose purpose will also be described more fully hereinafter.

A tubing string 38 has conventional sections 39 between which are connected a sealing nipple 42 and a hold-down 43. The sealing nipple includes a lower section 44 whose lower end is threaded into the coupling Alti at the upper end of the lower tubing section 39, an intermediate section 45 whose lower end is threadedl into the upper end of the lower seal nipple section 44, and an upper section de whose lower end is threaded into thenpper end of the intermediate seal nipple section.

The intermediate seal nipple section carries a packing 48 which `seals between the seal nip-ple Vand the packer mandrel. The packing 48 may be of the chevron type and be held in place by suitable split lock rings 49 and by a downwardly facing external annular shoulder 50 on the intermediate seal `nipple section.

The upperseal nipple section 46 is provided inter- -rnediate its ends with an external annular flange -52 kabove which is disposed a packing "53 Vheld thereonby a Vlock 4 ring 54 threaded on the upper end of said upper seal nipple section.

The upper seal nipple section extends upwardly into the bore of the hold-down body 56, which is threaded onto the lower end of the upper tubing section 39. The packing 53 seals between theupper seal nipple section and the hold-down body. i

Threaded into the lower end of the hold-down body is a collet lock member 58 whose upper end abuts the lower shoulder 59 of the external ange 52 of the upper seal nipple section to limit downward movement ofthe seal nipple with respect to the hold-down body.

The collet lock member has a plurality of dependent resilient collet or lock lingers 60 having at their lower free ends outwardly extending locking bosses 6l. The bosses are adapted to extend into theinternal annular locking recess 35 of the upper mandrel section to lock the hold-down body to the packer 17 when. theV seal nipple moves upwardly from the position shown in Figure 2 to that shown in Figure 3. The upper end of the intermediate seal nipple section 45 has an outwardly and downwardly beveled annular shoulder 64 which engages the correspondingly downwardly and outwardly beveled shoulders 65 at the lower inner ends oi the collet lingers 6G. Such engagement cams the resilient lingers 69' outwardly and moves the bosses 6l into the locking recess 35, where their upper shoulders 66 engage the downwardly facing annular shoulder 67 at the upper end of the recess 35 in the upper mandrel section of the packer. The collet lock bosses thus prevent further upward movement of the seal nipple with respect to the packer Vand the hold-down body.

In use, when 'it is desired to close the space between the tubing string and the casing at a desired location in the well, Va pack`er17 having collet bosses 14 of the vproper length yis lowered into the 'casing until it reaches the landing nipple 11 at the desired location, where the packer collet stop and lock'bosses 14 and l5 enter into the

grooves

12 and 13 of the landing nipple and stop further downward movement of the packer. It will be noted that the lower shoulders 68 of the lower collet bosses 15 are beveled outwardly vand upwardly so that the resilient collet lingers 23 of the packer collet member 16 are flexed inwardly when 4obstructions are encountered by the bosses 15 during the downward movement of the packer in the well casing.

The tubing string is provided with a seal nipple and "a hold-'down body between two adjacent sections, as

shown, at a proper location in the tubing string, and the tubing string is vthen lowered into the casing and passes through the packer 17 `until the downwardly and inwardly beveled shoulder 70 of the hold-down collet member 58 engages the stop shoulder 34 in the bore of .the` upper mandrel section. This engagement stops further downward movement of the tubing string in the casing.

The resilient collet fingers 60 of the hold-down collet member 58 liex inwardly (Figure 4) upon meeting obstructions in this downwardV movement of the tubing string into the casing and in the packer, since the bosses 61 on the lower ends of the lingers are provided with up wardly and outwardly beveled shoulders 72which cam the collet lingers inwardly upon engaging such obstructions as the stop shoulder 34 of the upper mandrel section.

. Thefseal nipplelpacking 48 and the packing 30 on the packing mandrel section then seal betweenthe seal nipple and the packer mandrel and between the packing mandrel section andthe landing nipple, thus eiiectively closing or sealing the space between the tubing lstring and the casing at the desired landingnipplell. Q

VThe lowerseal nipple section 44 now-abuts'the inner surface of thepackercollet lingers v23 and preventstheir inward movement. In effect, the lowenseal nipplesec Ation locks the collet bosses 1'4"an'd' 15 "of "the'packe'rin the annular recesses or

grooves

12 and 13 of the landing nipple, and thus locks the packer 17 in the landing nipple against any longitudinal movement therein. t

The hold-down action of the collet lock member S8 of the hold-down 43 becomes effective only if a pressure differential arises across the seal nipple which causes the seal nipple to move upwardly. When this happens, the shoulder 64 at the upper end of the intermediate seal nipple section 45 engages the shoulders 65 at the inner lower ends of the hold-down collet fingers 61 and locks the collet fingers against inward movement so that the upper shoulders 66 of the bosses 61 are held in engagement with the downwardly facing stop shoulder 60ct the packer mandrel. Thus, the hold-down collet bosses prevent further upward movement of the seal nipple.

It will be seen that the weight of the tubing string above the packer does not in any way influence the effectiveness of the hold-down, since a limited upward movement only 6 nipple. It'will also be seen that the hold-down isiprovided with locking bosses 61 which engage in the lock recess or groove 35 in the upper mandrel section of the packer 17 to lock the hold-down to the packer. It will be seen also that such locking bosses are held in locking position by the seal nipple, by engagement of the lock shoulder 64 of the seal nipple with the shoulders 65 at the l lower inner end of the hold-down collet fingers when the of the seal nipple results in a locking action which preseal nipple with the packer collet fingers 23, which engagement prevents inward movement of the fingers and lock keys, and not because of any action due to the weight of the tubing string. v

However, it will be noted that, because of the fact that the packer collet member 23 may undergo a limited longitudinal movement with respect to the tubular skirt 26 and because the lower end of the skirt may then engage the upper ends of the keys or lugs 24, the load of the tubing string above the packer will be supported by direct metal to metal engagement between the hold-down, the packer mandrel, the tubular skirt, the lugs or keys and the stop shoulders 18 and 19 of the keys and the nipple, respectively.

When it is desired to remove the tubing string upwardly, even though a pressure differential exists across the seal nipple which holds said seal nipple in the upper position shown in Figure 3, fluid pressure is introduced, as by a pump on the surface, into the annular. space between the tubing string and the casing above the packer 17 to cause a pressure differential which moves the seal nipple downwardly to the position shown in Figure 2. While this downwardly acting pressure differential is maintained, the tubing string is pulled upwardly, as shown in Figure 4, `whereupon the hold-down collet iingers 60 flex inwardly, since the upper shoulder 66 of the bosses 61 thereof are beveled downwardly and outwardly and cam the collet fingers inwardly to the position shown in Figure 4, upon meeting obstructions in their upward movement.

After the tubing string is removed, pressure above and below the packer 17 is equal and the packer can be removed by an upward pull exerted ron the internal flange 33 in the bore of the upper mandrel section by means of a suitable retrieving tool, since the packer collet fingers 23 are free to flex inwardly and the

bosses

14 and 15 are provided with outwardly and downwardly beveled shoulders '78 and 79', respectively, which cam the collet fingers inwardly upon meeting obstructions during upward movement in the casing. l

In the event .foreign particles have gathered between various operative elements of the hold-down, variations in the fluid pressure introduced into the space between the casing and the tubing string can be employed to cause reciprocal movement of the seal nipple until such foreign particles are dislodged or removed, thus freeing such elements for normal operation.

It will now be apparent that a new and improved packer hold-down has been illustrated and described which includes a packer 17 which can be positioned in aselected landing nipple 11 of a casing, a seal nipple 42 which is connected to the upper end of a lower section of a tubing string, and a hold-down 43connected to the lower end-of a tubing section which telescopesover the seal seal nipple is moved to an upper position by an upwardly acting pressure differential thereacross. It will be further seen that the seal nipple locks the packer locking means or

bosses

14 and 15 on the lugs or keys 24 in locking position when said seal nipple is extending through the packer, so that the packer is held thereby against upward movement in the casing.

t will also be apparent that the Apacker hold-down is operated automatically by the upwardly acting pressure differential across the'seal nipple to hold the; packer and seal nipple in operative positions, and that the packing elements may be moved into inoperative positions to permit removal thereof after the seal nipple has been moved downwardly by iluid pressure introduced into the annulus between the tubing string and the casing above the packer assembly. .p

Referring now to Figures 8 through 10 of the drawings, the casing 10 of a well is shown with a landing nipple 11 connected therein. The landing nipple 11 is similar to those described with the device of-Figures 1 through 7 and is provided with stop'and lock groove means 12 and 13 adapted to receive the packer stop and

lock bosses

14 and 15 of the collet member 16 of a packer 80. The packer is generally similar to the packer 17 of the device of Figures 1 through 7, and like parts are assigned like numbers.

The Vpacker collet bosses engage in the recess of a selected landing nipple to stop the packer against further downward movement in the casing andV to lock the packer against upwardr movement in the casing in the same manner as the form illustrated in Figures `1 through 7. The upper groove 12 of the landing nipple 11 may be of different longitudinal width from the corresponding groove of other landing nipples whereby the

bosses

14 and 15 of the packer 80 may enter only the recesses of the desired nipple.

The packer may be lowered into the casing by means of a suitable running tool, or it may bereleasably connected to a lowering sub 81 by means of shearable screws 8S threaded through the wall of the packing mandrel 85 into apertures or holes 91 formed in circumferentially spaced bosses welded on the exterior of the lowering sub. The lowering sub is connected to a lower tubing section 39 of the tubing by a coupling 40.

The packer 80 includes an upper mandrel section 80a into whose lower end the packing mandrel 85 is threaded and a tubular skirt 86 threaded into a counterbore in the lower end of said packing mandrel. vThe oounterbore provides an internal annular recessy 85a in the packing mandrel above the upper end `of the tubular skirt, and an external annular flange 25 at the upper end of the packer collet member 16 is confined in said recess. The sizes of the flange and of the recess are such that the collet member may undergo a limited longitudinal movement relative to the skirt 86 in the same manner and for the same reasons described in connection with the device of Figure 2. The packer collet member 16 is provided with a plurality of dependent resilient fingers Z3 and with keys` manner and for the same purposes described in connection with the device of Figure 2.

A packing 87, shown to be of the V type, is carried on the exterior of the packing mandrel between theV lower end of the upper mandrel section 80a and an upwardly facing external annular shoulder 31 on thepackingman- 7 drel, and seals between the landing nipple and the packing mandrel of the packer.

An internal annular flange 33 in the upper end of the bore of the upper mandrel section 80a provides a downwardly facing shoulder which may be engaged by suitable running or retrieving tools. The bore of the upper mandrel section is reduced below the ange to form an upwardly facing beveled stop shoulder 34 similar to that of the device of Figure 2. The reduced portion of the bore of the upper mandrel section is provided with an internal annular groove or locking recess 35 spaced below the stop shoulder 34, The bore of the upper mandrel section is enlarged below and contiguous to the groove 35 to a diameter greater than that of said groove to provide a relief bore or recess 84, for reasons to be hereinafter explained.

A hold-down 83 is connected to an upper section 39 of the tubing string 38. A sealing nipple S2 is connected to the lower end` of the hold-down, and the lowering sub 81 is connected to the lower end of the seal nipple by means of a coupling 93.

The sealing nipple includes a lower locking section 92 threaded onto the lower end of an upper seal nipple packing mandrel 94. A packing section 95, of the V type, is carried on the packing mandrel between the upper end of the locking section and a downwardly facing external annular shoulder 96 near the upper end of the packing mandrel.

The hold-down 83 includes a hold-down mandrel 97 threaded into the upper end of the seal nipple packing mandrel 94, and the upper end of said hold-down mandrel telescopes into the hold-down sub 9S threaded on lthe lower end of the upper tubing section 39. A holddown body 99 is threaded onto the lower end of Athe sub and extends downwardly therefrom surrounding the mandrel. The hold-down'body carries a packing 100 in its bore to seal between Said body and the mandrel 97. The packing 100 may be of the V type and is held in place between an internal annular flange 101 in the hold- Y down body and the lower end of the sub 98.

Threaded into the lower end of the body 99 and further surrounding the mandrel 97 is a hold-down collet member 102 whose upperend is spaced below the tlange 101 in the hold-down body and is adapted to abut the lower shoulder 103 of an external annular llange 104 on the hold-down mandrel to limit downward movement of said mandrel relative to the sub and body. The limit of upward movement of the mandrel in the body is determined by the engagement of the ilange 10d on the mandrel with the lower face 113 of the flange 101 in the body. Shearable screws 105 are threaded through the body inwardly into holes in the anges 104 in the mandrel to releasably hold the hold-down mandrel in its lower position with relation to the hold-down body;

The hold-down collet member has a plurality of dependent spring lingers 106 having at their lower free ends outwardly extending bosses 107 adapted to enter the annular locking recess 35 of the packer to lock the holddown body to the packer. An internal locking groove 108 is formed near the lower end of each linger for en gagement by an external annular locking ange or ring 109 secured on the hold-down mandrel, as by welding.

The upper face 110 of the locking ring 109 is outwardly yand downwardly beveled for engagement with beveled shoulders 111 at the lower inner ends of the spring lingers 106 to cam said lingers outwardly on upward movement of the hold-down mandrel in the body. When the ring s located in the locking grooves 108 in t'neVfmgers, said ylingers. return inwardly to their original positions, the

ring contacting the inner surfaces of the fingers in the grooves to limit inward movement of thengers. The

flange 104011 mandrel and theilange 101 in the body engage one another at thesametirne that thelring enters thelccking, grooves.

thelcnerngrsubrand -f the lowering sub, the seal nipple and the hold-down are connected in the tubing string between adjacent sections, as shown. The tubing is then lowered into the casing until the packer .lands in the landing nipple. The shearable screws 88 are sheared by further downward movement of the tubing string, and the seal nipple and hold-down are lowered into the packer until the downwardly and inwardly beveled shoulder 70 of the holddown collet member 102 engages the stop shoulder 34 in vthe bore of the packer, thus stopping downward movement of the tubing string.

The lingers 106 of the hold-down collet member ilex inwardly on meeting obstructions in the same manner as thoseV of the device of Figure 2, the bosses 107 being provided with upwardly and outwardly beveled shoulders 116 at their lower ends. The collet fingers and bosses are thus able to move downwardly into the packer to a position wherein the bosses are disposed in the annular relief bore 84 below the locking groove 3S.

When the downwardly facing shoulder 70 of the holddown contacts the upwardly facing shoulder 34 of the packer, the bosses 107 of the hold-down collet are located in the enlarged relief bore 84 of the packer mandrel. In this position the weight of the tubing string above the holddown is applied to the packer, and tluid pressure, as from a pump at the surface, is introduced through the tubing to the bore of the well below the packer. This fluid pressure acts on the seal nipple packing and forces said seal nipple and the hold-down mandrel 97 thereabove upwardly, shearing the frangible screws which initially holdV the hold-down mandrel in its lower position. With the frangible screws sheared, the holdfdownmandrel moves upwardly, moving the locking ring 109 on said hold-down mandrel upwardly between the fingers 106 of the hold-down collet member.

Since the bosses 107 of the hold-down collet member are disposed in the .enlarged relief bore 84, the lingers may spring outwardly suiciently to permit the locking ring 109 to move upwardly therebetween into the locking grooves 108 in the inner surfaces of the collet fingers.

When the locking ring is positioned in the locking grooves, the hold-down collet fingers'are held against contraction, and the bosses 107 are thus held in position to engage the downwardly facing shoulder 67 at the upper end of fthe locking groove 35 of the packer mandrel and the hold-down is locked against upward movement out of the packer. The tubing string is thus locked to the packer, and any upward uid pressure acting on the seal nipple 82 can move the lower end of the tubing string upwardly only until the bosses 107 engage the shoulder 67 in the upper packer mandrel.

The sealing nipple packing 95 andthe packing 87 on the packing mandrel 85 seal between the sealing nipple and the .packer and between the packer and the landing nipple in the. same manner as that of the device of Figure Vlower end of the Ihold-down to maintain a minimum length. Obviously additional tubing sections could be provided ybetween the lowering sub and the hold-down if it is desired to extend the lower end of the tubing beneath the Ypacker when said packer is set and locked in position.

`To release the hold-down from its locked position, the

-tubing'string is lowered until the collet member ofthe vhold-downis `supported by the shoulder 34 of the packer. Pressure is kappliedto the annulargspace above the packer )nutten shambles-.aad the-wierden; and gebeden@- upper endv of said bore.

wardly on the seal nipple to move the seal nipple and the hold-down mandrel 97 downwardly relative to the hold-down collet member, moving the locking ring 109 downwardly from between the collet fingers to permit the fingers to contract as the bosses 107 are moved upwardly past the shoulder 67 and out of the locking recess 35 of the packer mandrel. The hold-down and seal nipple are thus lifted from the packer and they and the tubing string then removed from the well. The packer may thus be removed in the same manner as was that of the form first described.

In the event that the tubing is stuck in position, as by solidified drilling mud in the annulus above the packer between the tubing andthe casing, whereby pressure applied at the surface is not transmitted throughthe mud to the packer, a removable pressure retaining plug (not shown) is lowered into and through the tubing by flexible line operations and anchored inv said tubing at a point below the hold-down to plug thebore of the tubing at that point. Fluid pressure is then introduced Vinto the tubing and causes the seal nipple and the hold-down mandrel to be moved downwardly relative to the hold-down body to released or unlocked position. Pressure may also be introduced into therannular space to assist in the 'releasing operation. Once the hold-down is unlocked, the removable plug can be removed from the tubing by means of exible line retrieving tools in the usual manner. The balance of the operations for removing the Ihold-down and the packer are the same as previously described.

It will be seen thatl a modified packer hold-down has been described and illustrated in which the hold-down body is provided with locking bosses which engage in a lock recess of the packer tolock the lhold-down body to the packer. It will also be seen that the locking bosses are held in locking position by a locking ring on the hold-down mandrel, tok limit upward movement of the tubing string by an upwardly acting fluid pressure difierential applied to the seal nipple. It will :be seen further that the locking ring is 4held in locking position between the hold-down collet fingers to lock the locking bosses in locking position. It will be seen .that the seal 'nipple locking section Ilocks the packer in position in the casing landing nipple in the same manner as did the first described'form of the hold-down.

It will also be apparent that the packer hold-down and seal nipple elements are movable downwardly to positions to permit the unlocking thereof by fluid pressure introduced into the annulus between the casing and the tubing string above the packer.

VIn Figures 1l and 12 a still further modified form of packer hold-down is shown in which an upwardpull on the tubing and on the hold-down retains said hold-down in locked position in the packer and thereby retains the packer in its locked position in the well.l

The upper end portion of a packer 117, shown in position in a landing nipple 11, is provided with a locking recess 35 in the upper end of the-bore of its mandrel and is in all respects similar to the packer 80 previously described except that the internal flange 33 is omitted.

The hold-down 118'includes a mandrel section 119 vwhose lower end-is threaded into the upper end of a sealing and locking nipple 120 which is similar to the sealing and locking nipple 82 of the device of Figures 8 through l0. The upper end of the hold-down mandrel l119 is connected to the lower end of the upper section 39 of the tubing string 38 by a coupling 40. A sleeve or collet supporting member 121 is slidable on the mandrel and carries in the upper portion 121e of its bore sealing .rings or packing 122 which seal between the mandrel and the sleeve member. The packing is retained between an internal flange 123 in the bore of the sleeve member 'and a bushing or retainer ring 124 'threaded into the *l 'An exterual-fiange 125-Ourthe mandrel 119 engages the lower face 126 of'the internal ange 123 of the sleeve member to limit downward movement of the sleeve member on the mandrel. Sealing rings or packing 127, shown to be of the V type", are carried on the hold-down mandrel section 119 between upper and lower splitretainer rings 128 and 129, respectively, located in an upper external groove 130 in the mandrel section immediately below the flange 125 and in a lower groove 131 in the mandrel spaced below the flange and upper groove. This packing also seals between the mandrel and the sleeve member. A port 132 is provided through the wall of the mandrel at the fiange to provide communication between the interior of the mandrel and the exterior thereof above the packing 127 on the mandrel but below the packing 122 carried n the sleeve member 1'21.

An annular chamber 132a of variable capacity is thus formed between the sleeve member and the mandrel, the ends of the chamber being closed by the

packing assemblies

122 and 127. The chamber communicates through the port 132 with the interior of the mandrel, for a purpose which will be hereinafter more fully explained.

A collet member 133 is threadedly connected with the `lower end of the sleeve member 121 and is slidable therewith on the mandrel section 119 below the lowerv split retainer ring v129. The colletmember has a plurality of dependent spring fingers 134, each having an outwardly extending boss 135 at its lower free end adapted to enter the annular locking recess 35 of the packer to lock the hold-down to the packer. The upper end of the collet member 133 abuts the lower face 136 of the lower split retainer ring 129 to limit upward movement of the sleeve 'member 121 relative to the mandrel section.

An external annular groove 137 is formed in mandrel section 119 at a point spaced -suiciently below Vthe lower retainer ring 129 to permit the lower end portions of the fingers of the collet member to flex inwardly as the bosses on said fingers are cammed inwardly inpassing vinto the upper end of the base of the packer 117. The

lower outer shoulders 138 of the bosses 135 are outwardly and upwardly beveled so that the fingers will be cammed inwardly on contact with the upwardly and outwardly Vbeveled -shoulder v139 at the upper end of the packer. The external groove 137 in the mandrel is of such depth that the collet fingers may readily flex thereinto to permit the bosses 135 to move into the boreV of the packer.

In use, the packer 117 is lowered into and landed in the nipple 11 in the casing in a manner similar tothe devices previously described. Thel seal nipple section 120 of the hold-down enters the packer to seal with said packer and to lock said packer in place, and the holddown is lowered until the beveled lower outer shoulders 138 of the bosses on the hold-down collet fingers encounter the beveled upper shoulder 139 of the packer.

vThe collet member and the sleeve member being stopped from further downward movement, the mandrel section moves downwardly until the retainer ring 129 engages the upper end of the collet member, whereupon further downward movement of the hold-down causes the lower ends of the resilient fingers 134 to be cammed inwardly into the groove 137, permitting the bosses to enter the bore of the packer 117 and the collet member to move downwardly until an external annular downwardly facing shoulder 140 on the collet memberA 133 engages the upwardly facing beveled shoulder 139'at the upper end of the packer. The fingers of the collet member then flex outwardly to their initial or normal positions, the bosses 135 entering Athe groove 3S in the packen The tubing is then lifted to bring the locking section 141 formed by the lower periphery of the mandrel Sec- .tion 119 behind the spring fingers 134 so that inward exure Yof said fingers is prevented by the engagement of said locking section with the inner surfaces of the fingers, thereby locking the hold-down to the packer. Ii the -tion on the mandrel.

ynormal conditions. .the hold-down tends to stick in either its upper or lower collet member 133 tends to move upwardly with the mandrel 119 when the tubing is raised to lock the holdkdown to the packer, pressure may be introduced into the annulus between the tubing and casing above Ythe packer to act on the upper end of the sleeve member 121 to assist the engagement of the bosses 135 in the groove 35 in resisting lupward movement of the sleeve while the mandrel section -is being raised to locking position.

Release of the hold-down is accomplished by lowering the tubing until the lower split retainer ring 129 abuts the upper end of the collet member 133, the external annular groove 127 then being located between the spring fingers 134. Fluid pressure is introduced from the surface into the tubing and enters through the port 132 in the ymandrel section into the chamber 132a. This pressure, acting on the differential area between the area of the internal diameter of the packing 122 and the external diameter of the packing 1127, exerts an upward force on the sleeve member to hold said sleeve in its upper posi- The upper faces 142 of the bosses 135 on the collet fingers are outwardly and downwardly beveled, and engage the downwardly facing shoulder 143 of the groove upon upward movement of the holddown, whereby the lower ends of the ngers are cammed into the groove 137 to permit the bosses to pass said shoulder and thereby permit the sleeve member to be disengaged and lifted from the packer. Removal of the packing section of the seal nipple from the packer causes release of the applied pressure,-thus giving an immediate indication at the surface that the hold-down is removed from the packer.

If the sleeve member tends to stick in its lower position on the mandrel section while the hold-down is being inserted into the packer, fluid pressure may similarly be introduced into the tubing to move the sleeve member upwardly relative to the :body member so that the ngers 134 may be exed inwardly. 1f desirable a removable Well tubing plug (not shown) may be inserted into the tubing .and installed below the hold-down to facilitate retention of the pressure introduced into the tubing.

The packer 117 can be removed in the manner similar to that described in connection with the devices of Figures l through l() except that with the packer 117 the retrieving tool engages the shoulder 143 in the groove 35 ,to exert an upward pull onthe packer.

It will now be apparent that a second modified form of packer hold-down has -been shown and described for use with a packer which can be positioned in a selected landing nipple of a casing and that this modified hold-down isso designed that tension on the tubing string exerts an upward force on the hold-down and the packer to retain said hold-down and the packer in locked position.

It will be seen that the hold-down is insertable into position in the packer and lockable therein simply by means of upward and downward movement of the tubing string and that no rotation or application of pressure is necessary to so insert and lock the hold-down under ln the event the sleeve member of position relative to the mandrel section of the hold-down, `said sleeve member can be moved upwardly or downywardly by the correct application of pressure from the vsurface to assist in inserting and locking the hold-down.

.Itwill further be seen that the hold-down is releasable fromthe packer by lowering the tubing string to move the hold-down mandrel section downwardly relative to the sleeve member, and that application of pressure within the tubing holds the sleeve member in this position on the mandrel, so that the exertion of an upward pull on the mandrel section removed the hold-down from the packer.

A still fnrthermodied form ,of packer hold-down is .shown in .Figures 1.13 and 14 inwhich the .weight of the .tubing is .utilized rito keep .the vhold-down 4.locked to vthe packer. Like parts to those of already described .figures are assigned like numbers.

A landing nipple -11 having internal grooves V(not shown) of the ype described and shownwith the earlier embodiments of the hold-down is attached in a casing 10 of a well. The upper end of a packer 117, identical with the packer of Figures 11 and l2, is shown as installed in the nipple in the same manner.

The hold-down 150 is designed to lock the tubing to the packer and the packer in the landing nipple by setting the weight of the tubing on the packer or `by uid pressure within the tubing acting on the hold-down elements. The hold-down includes a mandrel section 151 whose lower end is threaded into the upper end of a sealing and locking nipple identical with that of Figures 11 and l2 and whose upper end is connected -to an upper section 39 of the tubing string 38 by a coupling 40. A sleeve or collet supporting member 121, identical to that of Figures ll and 12, is slidable on the mandrel section and is similarly provided with a packing 122, an internal flange 123 and a bushing 124 threaded into its upper end.

The mandrel section 151 is similar to the mandrel section 119 of Figures ll and 12, in that it is provided with an external annular flange 125, a packing assembly 127 confined between upper and lower split packing retainer rings 128 and 129 located in upper and

lower grooves

130 and 131, respectively. The port 132 through the wall of the mandrel section establishes communication between the bore of said mandrel section and the sealed variable capacity anular chamber 132a formed between the packing

assemblies

122 and 127 and the inner wall of the sleeve member and the outer wall of the mandrel section.

A collet member 152 similar to the collet member 133 of Figures 1l and l2 is connected to the lower end of the `sleeve member 121, and shearable screws 153 are threaded through the wall of the collet member 152 and into recesses or holes 154 in 4the periphery of the mandrel sec'- tion 151 to releasably hold said collet member in its lowermost position on said mandrel section, as shown in Figure 14. The collet member has dependent resilient collet lingers 134 with external bosses 135 at their free lower ends, and the bosses are adapted to engage in the, recess 35 in the bore wall of the packer to lock the hold-down assembly to the packer.

The outer diameter of the lower portion of the mandrel section 151 is reduced to form a relief section 155 located behind the resilient vfingers 134 when the sleeve member is in its lowermost position on said mandrel section, whereby said iingers may be flexed inwardly to permit the bosses 135 to enter the bore of the packer 117. When the sleeve is moved toits uppermost position on the mandrel section, as shown in Figure 13,A the relief 155 is located below fingers 134 and the unreduced portion of the mandrel section 151 prevents inward 'ilexure of said iingers. n

In use, the packer is installed in the landing nipple in the manner already described and the tubing string 38 provided with the packer hold-down assembly and sealing and locking nipple is then lowered into and Vthrough the packer, the lower outer beveled shoulders 138 .of the Ibosses '135 ofhold-down collet fingers engaging the upwardly and outwardly beveled shoulder 139 at the upper end ofthe packer and being cammed inwardly thereby to move the fingers 134 into the relief 155 of the mandrel section so that the bosses 135 may enterthe packer. The collet member, being fixed in its lowermost position on the mandrel section by the shearable screws 153, .is held againts upward movement on said mandrel section by said screws to permit the collet tinger bosses to be moved into the bore of the packer. Engagement of the downwardly facing external stop shoulder 140 on' the vcollet member with the internal shoulder 139 inthe bore-ofthe packer stops further downward movement of the collet yand sleeve member. The eo1letingers 13.4 `springout- *l 13l wardly to their initial normal position wherein the bosses 135 are disposed in the recess 35 of the packer.

Further lowering of the tubing shears the shearable screws 153 and allows the mandrel section to move downwardly with respect to the sleeve and the collet member to the position of Figure 13. Such movement of the mandrel section moves the relief 155 in the outer surface of the mandrel 151 to a position below the fingers 134 and brings the unreduced portion of said mandrel section between the collet fingers to hold the lingers against inward movement, and thus locks the hold-down to the packer.

Some tubing weight can be left on the hold-down to maintain the mandrel section in holding position in the collet member. The inside diameter of the sleeve member engaged by the external diameter of the packing 127 and of the outside diameter of the upper portion of the mandrel section engaged by the packing 122 may be so selected and constructed that the anular area therebetween is equal to or greater than the annular area sealed olf by the packing assembly 156 on the sealing and locking nipple 120. If such areas are made equal, any pressure within the well tending to unseat the sealing and locking nipple will also act with equal force, through the port 132 and the chamber 1320, to bias the mandrel section 151 downwardly relative to the sleeve member 121 and the collet member 152 to its lowermost position, thereby maintaining the hold-down in locked position in the packer without the necessity of leaving the weight of the tubing on the packer.

If it is desired Vto increase the downward pressure 'force on the mandrel section to hold the hold-down in locked position, several sealed chambers 157 and 157:1 of variable capacity maybe employed, as shown in Figure 15. An lring or packing 158 within a gland nut 159 seals between said gland nut and an upper tubular mandrel section 160 connected to the lower end of the upper tubing section 39 by the coupling 40. The lower end of the upper mandrel section 160 is threaded into the upper end of a tubular mandrel piston section 161 carrying an external O- ring or packing 162 sealing with an upper sleeve or cylinder member 163. The gland nut 159 is screwed into the upper end of the upper sleeve or cylinder 163 and limits upward movement of the mandrel piston section 161 therein, while an internal annular ange 164 at the lower 'end of the cylinder member 163 limits downward movement of the piston mandrel section.

The mandrel piston section 161 has a reduced external diameter which forms a depending tubular mandrel section 165 preferably of the same outer diameter as the upper mandrel section`160, and an O-ring or packing 158a in the ange 164 seals with the mandrel section 165. A port 166through the wall of the upper mandrel section 160 just above the upper .end of the piston section 161 provides lfor conducting fluid pressure from the bore of the hold-down mandrel Vsection to the chamber 157 within the cylinder 163 and between thepackings -158 and 162. An additional port 167 through the ange 164 above its packing 158a provides for admitting external fluid pressure to the space between the cylinder and mandrel section below the packing 162 but above the packing 15811.

An additional ysleeve or cylinder 163a isrthreadedly connected to the lower end of the flange 164 to form,

`with an additional mandrel piston section 161a lattached to the lower end of the tubular mandrel section 165 and having an O-ring 162a to seal with said cylinder, an additional sealed chamber 157a. A port 166:1 extends through the wall of the tubular mandrel section 165 just above the piston section l61a attached be`ow, and a port 167a extends through the wall of the ange l64a at the lower end of the cylinder l63a. A tubular mandrel section 165:1, identical to the mandrel 165, depends from the pistonl section 161e. An O-ring-158a in ,the ange 164a seals with the mandrel section 165e.

' As many additional sealed chambers 157a as desired may be so formed. A sleeve or collet carrying member 168 is threaded to the lower end of the lowest ange 164a, and a collet member 152 is threaded into the sleeve. A lower mandrel section 169 having a piston 161a and an 0ring 162g is threaded to the lowermost tubular mandrel section 165:1 and is provided with threaded holes 154 into which shearable screws 153 may be threaded through the collet member 152. A relief 155 is formed on the lower mandrel section 169 and, when the collet member 152 and the attached sleeve 168 are in their lowermost positions on the mandrel section 169, the resilient -ingers v134 may ilex inwardly so that the bosses 135 on the collet tingers 134 may enter the packer and the recess 35. The fingers are cammed inwardly to enter the packer by the engagement of the beveled shoulders 138 of the bosses 135 with the beveled upper end 139 of the packer.

Thus operation of the form of the invention shown in Figure 15 is the same as that of Figures 13 and 14. Well pressure tending to move the sealing and locking nipple upwardly enters the chambers 157 and 157a through the ports 166 and 166a and, acting on the packings at the ends of the cylinders, urges the cylinders and the collet member upwardly relative to the mandrel piston sections, the total upward force on the cylinders and the collet member being the sum of the forces exerted within the several chambers 157.

Obviously, if the pressure in the annular space between the tubing and the casing above the packer is. greater than Athe well pressure, the cylinders would be urged downwardly relative to the mandrel piston sections. However, in such event there would be no tendency for the seal nipple and hold-down to be moved upwardly lby the well pressure, it being locked.

Removal of the hold-down of Figures 13 and 14 or that of Figure 15 is accomplished by lifting the tubing string and the mandrel sections of the hold-down. As the relief in the outer surface of the mandrel section moves between the resilient fingers 13'4,`the upwardly and inthen immaterial that the hold-down be wardly beveled'faces 142 of the bosses 135 cam. the

iingers 134 inwardly by contact with the shoulder 143 of the recess 35 so that the hold-down may be removed from the packer. The packer is removed from the casing in the same manner as with the other forms of the invention. Y

, It will be apparent that a further modified form of packer hold-down has been illustrated and described for use with a packer positionable in a selected landing nipple -of a well casing, in which the hold-down is insertable into and lockable in the packer simply by upward and downward movement of the tubing string, and is removable simply by an upward pull exerted thereon through the tubing string.`

It will be seen-that a. pressure-sensitive device in .the form of a sealed chamber or chambers is incorporatedv into the hold-down to cause pressure within the well bore Yto assist in holding the hold-down in secured position in the packer. The provisions of a plurality of such chambers provides for an increased force to hold the holdktory only, and changes in the details of the cc'mstructionsV illustrated may be made by those skilled in the art,rwith in thescope of the appended claims,'without departing from the spirit of the invention. Y

What is claimed and desired tobe secured by Letters Patent is:

1. A well dew'ce comprising: a packer positionable at a desired location in a casing; said packer comprising a tubular packer body; a tubular member removably insertable in said packer and having a seal nipple and a tubular hold-down body, said seal nipple being insertable in said packer body in sealing relation therewith, said seal nipple and hold-down body being telescopically connected and capable of limited longitudinal movement relative to one another; rst locking means on said packer engageable with said casing for holding said packer at said desired location; second loc-king means comprising means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said packer; and means on said seal nipple engageable with said second locking means for holding said second locking means in operative locking position limiting relative movement between said hold-down body and said packer.

2. A well device comprising: a landing nipple adapted to be connected in a well iiow conductor; a packer cornprising a tubular packer body positionable in said landing nipple; a tubular member removably insertable in said packer body and including `a seal nipple and a tubular hold-down body, said seal nipple being insertable in said .packer body in sealing relation therewith, said seal nipple and hold-down body being slidably connected and capable of limited longitudinal movement relative to one another; cooperating locking means on said packer and said landing nipple for holdingsaid packer in -said landing nipple; a second cooperating locking means `comprising means on said packer body and said hold-down body coengageable for removably securing Vsaid `holddown body to said packer; and means on said seal nipple engageable with said second cooperating locking means for holding said second locking means in operative locking position limiting relative movement between said holddown body and said packer.

3. A well device comprising: a landing nipple Vadapted to be connected ina Well ow conductor; a packer comprising a tubular packer body positionable in said land ing nipple; a tubular member removably insertable in said packer and including a seal nipple and a tubular hold-down body, said seal nipple being insertable in said packer body in sealing relation therewith, said seal nipple and hold-down body being slidably connected and capable of limited longitudinal movement relative to one another; cooperating locking means on said packer body Vand said landing nipple for holding said packer in said landing nipple; a second locking means comprising ,means on `said packer body and said holddown body coengageable for removably securing said hold-downbody to said packer; and means on said seal nipple engageable with said second locking means for Aholding said second locking means in operative locking position limiting relative movement between said hold-down body and said packer, said seal nipple engaging said tirst locking means for holding said iirst locking means in operative locking position preventing relative movement between said packer and said landing nipple.

4. A well device comprising: la packer comprising a tubular packer body positionableat a desired location in a well casing; a tubular vmember removably insertable in said packer and having a seal nipple and a tubular `holddown body, said seal nipple Vbeing insertable infsaid packer body in sealing relation therewith, said sealnipple and hold-down body being telescoped and capable of .limited longitudinal movement` relative to'one another;

looking means on said packer body engageablewith said casing Yfor holding `said packer at said desired location; a secondlocking means comprising means on .said lpacker body .and said hold-down1body for removably securing Vsaidhold-down body to said packer; and means on `said `seal nipple engageable with said second locking means when said seal nipple is moved to an upper position by a pressure differential thereacross for holding said second locking means in operative locking position preventing further upward movement of said seal nipple relative to said packer, and cooperating stop means on said holddown body and said packer limiting downward movement of said tubular member through said packer when said seal nipple is positioned in said packer.

5. A well comprising: a landing nipple adapted to be connected in a well ow conductor; a packer comprising `an elongated tubular packer body positionable in said landing nipple; a tubular member removably insertable in said packer body and having a seal nipple and a tubular hold-down body, said seal nipple being insertable in said packer body in sealing relation therewith, said seal nipple and hold-down body being telescopically connected and capable of limited longitudinal movement relative to one another; cooperating locking means on said packer and said landing nipple coengageable for holding said packer in said landing nipple; a second locking means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said packer, and means on said seal nipple engageable with said second locking means for holding said second locking means in operative locking position limiting upward relative movement between said hold-down body and said packer, said seal nipple engaging said first locking means for holding said iirst locking means in operative locking position preventing relative movement between said packer and said landing nipple; and cooperating stop means on said hold-down body and said packer body limiting downward movement of said tubular member through said packer body when said seal nipple is positioned in said packer.

6. A well device comprising: a packer comprising a tubular packer body selectively positionable at a desired location in a well casing; a tubular member removably positionable in said packer body and having a seal nipple and a hold-down body, said seal nipple being insertable in said packer body in sealing relation therewith, said 4sealnipple and hold-down body being telescopically connected and capable of limited longitudinal movement relative tovone another; locking means on said packer engageable with said casing for holding said packer at said desired location; cooperating locking means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said packer; means on said seal nipple engageable with said cooperating locking means for holding said cooperating locking means in operative locking position Vlimiting upward relative movement between said hold-down body and said packer body; sealing means on saidpacker body for sealing between said packer body and said casing; and sealingmeans onwsaid seal nipple lfor sealing between said sealnipple and said packer body.

7. A well device of the character set forth in claim 2 including: sealing means on said packer body for sealing between said packer and said landing nipple; and sealing means on said seal nipple for sealing between said seal nipple andrsaid packer body.

Vit. A well device comprising: a packer selectively positionable at a desiredlocation in Va casing; said packer comprising a tubular packer body; a tubular member movable through said packer and having a seal nipple and a tubular hold-down body, saidseal nipple and holddown body being telescopically connected'and capable of limited longitudinal movement relative to one another; locking means on said packer engageable with saidcasing for holding said packer at said desired location; a Vsecond locking means on said packer comprising cooperative nipple engageable with said packer body for sealing therebetween, whereby a Vuid pressure differential may aereas;

vbe applied thereto to move said seal nipple upwardly relative to said packer body; means on said lseal nipple engageable with said second locking means when said seal nipple is moved to an upper position by a pressure differential thereacross for holding said second locking means` in operative locking position limiting upward relative movement between said hold-down body and said packer; cooperating stop means on said hold-down body and said packer limiting downward movement of fsaid tubular member through said packer when said seal nipple is positioned in said packer; and sealing meanson said packer for sealing between said packer and said casing.

9. A well device comprising: a packer selectively positionable at a desired location in a casing; said packer comprising a tubular packer body; a tubular member movable through said packer and having a sealrnipple and a tubular hold-down body, said seal nipple and holddown body being telescopically connected and capable of limited longitudinal movement relative to one another; locking means on said packer engageable with said casing for holding said packer at said desired location; a second locking meansv on said packer comprising cooperative means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said packer body; sealing means on said seal nipple engageable with said packer body for sealing therebetween, whereby a fluid pressure differential may be applied thereto to move said seal nipple upwardly relative to said packer body; means on said seal nipple engageable with said second locking means when said seal nipple is moved to an upper position by a pressure differential thereacross for holding said second vlocking means in operative locking position limiting upward l relative movement between said hold-down body and said packer, said seal nipple engaging said first locking means for holding said first locking means in operativey locking ,position preventing relative movement between said packer and said casing; cooperating stop means on said hold-down body and said packer limiting downward movement of said tubular member through said packer when said seal nipple is positioned in said packer; Vand sealing means on said packer for sealing between said packer and said casing.

10. A Well device comprising: a packer selectively positionable at a desired location in a casing; said packer comprising a tubular packer body having Vsealing means thereon for sealing between said packer body andY said casing and having anchoring means for anchoring said body in said casing; hold-down means connectible between adjoining sections of a tubing string andy including a seal nipple and a tubular hold-down body, said seal nipple and said hold-down body being telescopically connected and capable of limited longitudinal movement relative to one another, said seal nipple being insertable into said packer body; sealing means on said seal nipple for sealing between said real nipple and said packer body; cooperating locking means on said packer body and said hold-down body coengageable vfor removably securing said hold-down body to said packer body; restraining means on said seal nipple engageable with said cooperating locking means when said seal nipple is moved relative to said hold-down body for holding said locking means in inoperative locking position limiting relative movement between said hold-down body and said packer; and means on said seal nipple exposed to fluid pressure in lsaid well Vfor moving said restraining means to and holding said means in engagement with said locking means.

11. A well device comprising: a packer selectively positionable at a desired location in a casing; said packer comprising a tubular packer body having sealing means thereon for sealing between said packer body and said casing and having anchoring means for anchoring said body in said casing; hold-down means connectible between adjoining sections of a tubing string and including -a seal nipple and a tubular hold-down body, said seal nipple and said hold-down body being telescopically connected and capable of limited longitudinal movement relative to one another, said seal nipple being insertable into said packer body; sealing means on said seal nipple for sealing between said seal nipple and said packer body; cooperating locking means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said body packer; restraining means on said seal nipple engageable with said cooperating locking means when said seal nipple is moved longitudinally relative to said hold-down body for holding said locking means in operative locking position limiting relative movement between said hold-down body and said packer; means on said seal nipple exposed to vfluid pressure in said well for moving said restraining means into engagement with said locking means; and cooperating stop means on said hold-down body and said packer body for limiting downward movement of said sealing nipple in said` packer body.

12. A well device comprising: a packer selectively positionable at a desired location in a casing; said packer comprising a tubular packer body having sealing means thereon for sealing between said packer body and said casing and having anchoring means for anchoring said body in said casing; hold-down means connectible between adjoining sections of a tubing string and including a seal nipple and a tubular hold-down body, said seal Vnipple and said hold-down body being telescopically connected and capable of limited longitudinal movement relative to one another, said seal nipple being insertable into said packer body; sealing means on said seal nipple for sealing between said seal nipple and said packer body; cooperating locking means on said packer body and said hold-down body coengageable for lremovably securing said hold-down body to said body packer; restraining means on said seal nipple engageable with said cooperating locking means when said seal nipplepis moved longitudinally relative to said hold-down body for holding said locking ,means in operative locking position limiting relative movement between said holddown body and said packer; means on said seal nipple exposed to fluid pressure in said well for moving said restraining means into engagement with said locking means; said seal nipple having a portion engaging and holding said anchoring means in locking position when said seal nipple is in position in said packer. y

13. A well device comprising: a packer selectively positionable at a desired location in a casing; said packer comprising a tubular packer body having sealing means thereon for sealing between said packer body and said casing and having anchoring means for anchoring said body in said casing; hold-down means connectible between adjoining sections of a tubing string and including a seal nipple and a tubular hold-down body, said seal nipple and said hold-down body being telescopically connected and capable of limited longitudinal movement relative to one another, said seal nipple being insertable into said packer body; sealing means on said seal nipple for sealing between said seal nipple and said packer body; cooperating locking means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said packer body; restraining means on said seal nipple engageable with said cooperating locking means when said seal nipple is moved longitudinally relativeto said hold-down body for holding said locking means in operative locking position limiting relative movement between said hold-down body and said packer; cooperating stop means on said hold-down body and said packer for limiting downward movement of said sealing nipple in said packer; and means on Said seal nipple exposed to fluid pressure in said well for' amasar engageable for mechanically restraining said seal nipple in position engaging said locking means; said seal nipple holding said packer anchoring means in locking position engaging said casing when said seal nipple is in position in said packer.

14. A well device of the character set forth in claim l wherein: said first locking means includes a collet member on said packer body having outwardly biased bosses, and said casing has a locking recess for receiving said bosses.

15. A Well device of the character set forth in claim 1 wherein: said second locking means includes a collet member on said hold-down body having outwardly biased bosses, and said packer body has an internal locking recess for receiving said bosses.

16. A well device of the character set forth inclaim 1 wherein: said tirst locking means includes a collet member on said packer body having outwardly biased bosses; said casing has a locking recess for receiving said bosses; said second locking meansv includes a collet member on said hold-down body having outwardly biased bosses; and said packer body has an internal locking recess for receiving said bosses.

17. A well device including: a packer positionable at a desired location in a casing comprising a tubular mandrel having an internal lock recess; expansible lock means on said mandrel movable outwardly into locking engagement with a casing to lock said mandrel in the casing; and a holddown comprising: a seal nipple positionable in the mandrel in said sealing relation therewith and er1- gageable with said lock means, said seal nipple being engageable with and holding said lock means of said mandrel in expanded position when positioned in said mandrel; a tubular hold-down body telescoped over said seal nipple and slidably connected thereto, said hold-down body having a second expansible lock means thereon movable outwardly into said internal lock recess of said mandrel, said seal nipple and said hold-down body being capable of limited longitudinal movement relative to one another, and means on said vseal nipple engageable with said second lock means of said hold-down to hold said second back means in expanded position when said seal nipple is moved longitudinally to one extreme position relative to said hold-down body, whereby said hold-down body is locked to said mandrel.

18. A well device including: va packer positionable at a desired location in a casing comprising a tubular mandrel having an internal lock recess, expansible lock means on said mandrel movable outwardly into locking engagement with a casing to lock said mandrel in the casing; and a hold-down comprising: a seal nipple positionable in the mandrel in sealing relation therewith and engageable with said lock means, said seal nipple being engageable with and holding said lock means of said mandrel in expanded position when positioned in said mandrel, a tubular holddown body telescoped over said seal nipple and slidably connected thereto, said hold-down body having a second expansible lock means movable outwardly into said internal lock recess of said mandrel, said seal nipple and said hold-down body being capable of limited longitudinal movement relative to one another, said seal nipple having means thereon engageable with said second lock means of said hold-down for holding said second lock means of said hold-down in expanded position when said seal nipple is moved longitudinally to one extreme position relative to said hold-down body, whereby said holddown body is locked to said mandrel; said packer man- 20 drel having seal means for sealing between said packer and said casing; and said seal nipple having seal means for sealing between said packer mandrel and said seal nipple.

19. A well device including: a landing nipple adapted to be connected in a well casing and having an internal annular locking recess therein; a packer comprising a tubular mandrel having an internal lock recess, expansible lock means resiliently mounted on said mandrel and movable into said locking recess of Said landing nipple to lock said mandrel in the nipple; and a hold-down comprising: a seal nipple positionable in the mandrel, said seal nipple being engageable and holding said lock means of said mandrel in expanded position when positioned in said mandrel, a hold-down body telescopically connected with said seal nipple, second expansible lock means resiliently mounted on said hold-down body andmovable into said internal lock recess of said mandrel, said seal nipple and said hold-down body being capable of limited longitudinal movement relative to one another, said seal nipple having means thereon engageable with said second lock means for holding said second lock means in expanded position when said seal nipple is moved longitudinally to one extreme position relative to said holddown body, whereby said hold-down is locked to vsaid mandrel; said packer mandrel having seal means for sealing between said packer and said casing; said seal nipple having seal means for sealing between said packer mandrel and said seal nipple; both said lock means comprising members having resilient iingers provided with outwardly extending bosses.

20. A well device comprising: a packer having a body with a longitudinally bore therethrough and positionable at a desired location in a casing; a member removably insertable in the bore of said packer body and having a seal nipple and a tubular hold-down body, said seal nipple and hold-down body having a connection providing for limited longitudinal movement of said nipple and body relative to one another; first locking means on said packer body engageable with said casing for holding said packer at said desired location; second locking means on said packer body and said hold-down body coengageable for removably securing said hold-down body to said packer; and means on said seal nipple and said hold-down body coengageable to maintain said seal nipple in` position in said packer body and holding said second locking means in operative locking position limiting relative movement between said hold-down body and said packer.

21. A well device of the character set forth in claim l including: means on said seal nipple and means on said hold-down body coengageable for restraining movement of said seal nipple relative to said hold-down body whereby said means for holding said second locking means in operative locking position is restrained against movement from engagement with said second locking means when said means on said seal nipple and said means on said hold down body are engaged.

References Cited in the tile of this patent UNITED STATES PATENTS 2,392,244 Hooser Jan. l, 1946 2,673,614 Miller Mar. 30, 1954 2,698,056 Marshall et al. Dec. 28, 1954 2,726,723 Wilhoit et al. -'Dec. 13, 1955 2,726,724 Wilhoit et al. Dec. 13, 1955 UNITED STATES PATENT oEEIcE CERTIFICATION OF CORRECTION Patent Noon 2,972,381 February 2l, 1961l George Max Raulins It is hereby certifiedthat error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column l, line 9, after l'vwell" insert device 5; column 17 line 64, for "inoperative" read operative column 18, lines 9 and 36, for ."loody packer", each occurrence, read packer body column 19, line 42, for "back". read lock Signed and sealed this 8th day of August 1961,.

(SEAL) Attest:

ERNEST W. SWIDER Attesting Officer DAVID L. LADD Commissioner of Patents