US2929453A

US2929453A - Well packer apparatus

Info

Publication number: US2929453A
Application number: US597920A
Authority: US
Inventors: Martin B Conrad
Original assignee: Baker Oil Tools Inc
Current assignee: Baker Hughes Oilfield Operations LLC
Priority date: 1956-07-16
Filing date: 1956-07-16
Publication date: 1960-03-22
Anticipated expiration: 1977-03-22

Description

March 22, 1960 M. B. CONRAD WELL PACKER'APPARATUS 3 Sheets-Sheet 1 Filed July 16, 1956 IN V EN TOR.

Mqer/A/ B. Cam/e40 March 22, 1960 M. B. CONRAD WELL PACKER APPARATUS I5 Sheets-Sheet 2 Filed July 16, 1956 INVENTOR. Maer/n .6. 60/1464 0 March 22, 1960 M. B. CONRAD 2,929,453

WELL PACKER APPARATUS Filed July 16, 1956 3 Sheets-Sheet 3- IN V EN TOR.

Myer/w 3. Cow/6 90 United States Patent 9 WELL PACKER APPARATUS Application July 16, 1956, Serial No. 597,920 20 Claims. (Cl. 166-134) The present invention relates to subsurface well apparatus, and more particularly to well packers adapted to be set in well casings, and similar conduits, disposed in well bores.

An object of the present invention is to provide a well packer apparatus capable of being lowered in a well casing on a tubular production string, anchored in the well casing against upward movement through proper manipulation of the production string, and then used to direct production into the tubular string, all with a single trip of the apparatus and tubular string in the well casing. 7

Another object of the invention is to provide improved well packer apparatus capable of being anchored in a well casing against movement in both longitudinal directions in response to mechanical'movement of the tubular string with which the packer is lowered to its setting location.

A further object of the invention is to provide a positively acting device for mechanically tripping and expanding a set of slips against the wall of a surrounding well casing. More specifically, an upwardly holding set of slips is mechanically tripped and expanded against the wall of the well casing by taking an upward strain on a running-in string, by means of which the apparatus embodying the slips is run in the well casing to the desired setting location. i

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

Figures 1 and 1a together constitute a longitudinal section, with parts shown in side elevation, through a well packer apparatus, with the parts in the condition occupied for lowering the apparatus in a well casing, Fig. 1a constituting a lower continuation of Fig. 1;

Fig. 2 is a cross-section taken along the line 2-2 on Fig 1; i

Fig. 3 is a cross-section taken along the line 3-3 on Fig. 1;

Figs. 4 and 4a together constitute a view similar to Figs. 1 and la, with the parts occupying another relative position; v

Fig. 5 is an enlarged fragmentary longitudinal section through a portion of the slip tripping mechanism, with the parts occupying the position illustrated in Fig. 1;

Figs. 6 and 6a together are views corresponding to Figs. 1 and la, with the parts in still another relative position, Fig. 6a constituting a lower continuation of Fig. 6.

The apparatus specifically disclosed in the drawings includes a well packer A which is to be anchored in packed-off condition within a Well casing B through suitable manipulation of a tubular string C, such as tubing, extending to the top of the hole, and by means of which the apparatus is operated. The apparatus is such that it is run in the hole on the tubular string C with the packer parts in retracted position. The packer A is anchored in packed-01f condition against the well casing B by manipulation of the tubular string C, and the latter then remains in appropriate relation to the well packer, in order that production from the well bore below the packer can be conducted to the top'of the hole. In other words, the apparatus A is such that it can be run in the well bore on a string at production tubing, set in place, and the production tubing then used for conducting the production to the top of the hole, all-with a single run of the equipment in the well casing B, thereby elfecting substantial savings in time and money.

The well packer is .of the general type disclosed in United States Patent No. 2,189,703, although patentable improvements have been made thereto to accomplish the purposes of the present invention. As disclosed in the drawings, the well packer A includes a tubular body 10 having an enlarged upper head 11, the interior of which is constituted as a threaded box 12 provided with left-hand threads 13. The lower portion of the body may be formed as an abutment 14 threadedly secured to the main portion of the body. A set of lower segmental slips 15 is disposed around the body 10, bearing upon the lower abutment, these slips being-initially held in retracted position by shear screws 16 securing them to a lower conical expander 17, which is, in turn, re leasably secured to the body ltlby one or more shear screws 18 The lower set of slips 15 and lower expander 17 serve to anchor the well packer to the well casing against downward movement, as explained hereinbelow.

Disposed above the lower expander 17 and encom.- passing the packer body is an initially retracted packing sleeve 19, which may be made of rubber, or rubberlike material, the upper end of which engages an upper conical expander 20 releasably secured to the body of the well packer by one or more shear screws 21. This upper expander coacts with an upper set of segmental slips 22 surrounding the body, which are held initially ,in retracted position by shear screws 23 attaching them to the upper expander. The upper slips22 bear upon an upper abutment and expander 24 which is slidable with respect to the body 10 of the tool, this upper abut,- ment member having internal circular cam teeth 25 thereon coating with companion external cam teeth 26 on a split lock or ratchet ring 27, the internal surface of which is provided with circular ratchetteeth 28 coacting with companion ratchet teeth 29 formed on the periphery of the packer body. The

ratchet teeth

28, 29 are so disposedv as to permit the body 10 to move upwardly within the ratchet ring 27, whereas anytendency for the body to move downwardly couples the ratchet ring 27 thereto, and causes the cam teeth 25-, 26 to tend to hold the ring coupled to the body, so that the body 10 is, in effect, clutched to the upper abutment 24 against downward movement with respect thereto.

Although not essential to the present invention, the well packer of the type disclosed may include a'slotted junk pusher 30 secured to the lower ,body abutment 14 by means of screws 31. This junk pusher 30 will prevent premature tripping of the slips 15 during lowering of the apparatus in the well casing. A flapper valve member 32 may also be pivotally mounted on the lower body abutment member 14, there being a spring 33 tending to urge such flapper valve upwardly to 'a closed posi- .of the latter screw or screws are, in turn, substantially less than the shearing force required to disrupt the shear screw or

screws

18, 16 holding the lower expander 17 to the body and the lower slips to the lower expander. In the setting of the well packer apparatus A, the shear screws 23 holding the upper slips 22 to the expander 20 will be disrupted first, in order that upward movement of the body 10 of the tool will shift the upper expander 20 upwardly within the upper slips 22, the latter being .forced outwardly into anchoring engagement with the wall of the well casing B. Thereafter, a continuation of 'the upward strain and movement of the body 10 will shear the screws 21 holding the upper expander 20 to the body 10, causing the lower expander 17 to move toward the upper expander, foreshortening the packing sleeve 19 and expanding it into sealing engagement with the wall of the well casing B. Thereafter, a

continuation and increase in the upward strain and movement on the body will shear the screw or

screws

18, 16 holding the lower expander 17 to the body and the lower slips 15 to the lower expander, the lower slips being moved by the lower abutment 14 along the lower expander 17 and outwardly into anchoring engagement with the wall of the well casing. All of this movement is permitted since the ratchet sleeve or clutch element 27 allows upward ratcheting of the body 10 with respect to the upper abutment member 24.

r The upper set of slips 22 is prevented by a holding or tripping means from moving initially in an upward direction in a positive manner, to effect a shearing of its screws 23 and its outward expansion against the well casing. Thus, the mechanism for tripping the upper slips of the well packer includes a set of segmental or auxiliary setting slips 35, which are circumferentially spaced from one another and which are secured to an inherently expansible band 36 by means of screws 37. The band 36 is not circumferentially continuous. As shown most clearly in Fig. 3, it has an arcuate extent of substantially less than 360. The band 36, if unrestrained, would straighten out. However, when it is confined in the arcuate condition shown in Fig. 3, the setting slip segments are about 120 apart. This arcuate disposition, however, can be changed if desired, which is alsotrue of the number of slip segments 35 employed.

The setting slips 35 have internal surfaces 38 tapering in an upward and inward direction, which are adapted tocoact with a companion external expander surface 3? on the upper portion of the upper abutment 24. The slips 35 have wickers 40 on their exteriors. which will embed themselves in the wall of the well casing B, and coact with the upper abutment 24 to prevent upward movement of the abutment with respect to the casing, as well as upward movement of the upper set of slips 22 of the well packer A itself.

The auxiliary setting slips 35 are held initially in a retracted position by a confining retaining sleeve that holds the setting slips initially immediately below'the body head 11 and initially'spaced above the upper end of the upper abutment 24. This sleeve may rest upon a shoulder 46 formed in the upper abutment 24. It also has an internal thread 47 meshing with an external thread 48 provided on the body head 11. It is preferred that only a few thread turns 47 be used on the retaining sleeve 45, whereas the body threads 48 have a substantial number of turns extending a substantial distance along thebody head 11. As an example, theinternal threads 47 on the sleeve may make two turns, whereas the threads 48 on the body with which the internal threads mesh may;

consist of about fifteen turns. The desirability of this threaded relation will be described hereinbelow.

The retaining sleeve 45 is threaded on the head 11 in a downward direction until its lower end 49 engages the upper abutment shoulder 46, at which time the sleeve is threaded to its fullest extent in a downward direction with respect to the packer body 10. Such extent of downward threading is determined by a rotational stop, including a pin 50 secured to the sleeve 45 and projecting inwardly to engage a generally vertical stop face 51 provided on the upper end of the packer body 10 above its threaded portion 48. The

threads

48, 47 on the body and the sleeve are of a right-hand, so that downward right-hand threading of the sleeve 45 on the body 10 will feed the sleeve downwardly until its lower end 49 engages the abutment shoulder 46, as determined by engagement of the rotational stop pin 5% with the vertical face 51 of the body.

The auxiliary setting slips 35 are initially retained in an ineffective position, such as disclosed in Fig. 1, by the encompassing retaining sleeve 45. When these slips are to be freed, the body 10 of the tool is rotated with respect to the sleeve 45 in a right-hand direction, to cause the sleeve 45 to feed relatively upwardly along the body, until it is shifted to a position above the setting slips 35, as limited by engagement of an internal stop shoulder 52 at the lower end of the sleeve with a split stop ring 53 located in a peripheral groove 54 in the body below its external thread 48. To secure such relative rotation, turning of the retaining sleeve 45 is resisted by a friction drag device 55. This friction drag device includes a sleeve member 56, the lower end of which is secured to the upper end of the retaining sleeve 45 by one or more shear pins or screws 57 The sleeve 56 has circumferentially spaced longitudinal grooves 58 therein in which friction dragblocks 59 are slidable, the outer surfaces of these drag blocks being urged against the wall of-the well casing B by helical compression springs 60- acting between the sleeve 56 and the drag blocks, outward movement of the blocks 59 being limited by engagement of their upper and lower ends 61 with upper and lower rirn portions 62 secured to or integral with the drag sleeve. In view of the frictional engagement of the drag blocks 59 with the well casing B, and the attachment of the drag sleeve 56 with the retaining sleeve 45, it is evident that rotation of the latter is prevened, or at least resisted.

Rotation'of the body 10 occurs as a result of rotating the tubular string C, which is threadedly attached to a setting mandrel 63 releasably connected to the body iii of the tool. This setting mandrel includes an upper section 64 threaded onto the tubular string C and which has a depending skirt 65 adapted to bear against the upper end of the packer body 10. The setting mandrel further includes an intermediate section 66 threadedly secured to the upper section 64, and which extends down wardly into the body passage 67, being threadedly secured to a lower section 68. The intermediate and

lower sections

66, 68 define a groove 69 therebetween in which a packing assembly 70 is contained, adapted to sealingly engage the wall 71 of the well body 10, in order to prevent leakage of fluid in both'directions between the mandrel 63 and the body wall 71.

The intermediate section 66 is connected to the body by a threaded coupling ring 72 having external left-hand threads 73 meshing with internal left-hand threadslli in the body head 11. This coupling ring 72 is solid and circumferentially continuous, being connected to the mandrel to rotate therewith by means of a key 74 fixed to the mandrel 66 and relatively slidable within a keyway 75 in the coupling ring, the coupling ring actually being'permitted to move upwardly along the mandrel 66,'when being unthreaded from the body 10, and into a cavity 76 defined between the intermediate section 66 of the mandrel and the depending skirt 65 of the upper section .64} Qof the mandrel. The coupling ring 72 is movable downwardly relative to the intermediate section 66 to the extent limited by engagement of its lower end with an upwardly facing shoulder 77 on the intermediate mandrel section.

The mandrel 63 may be connected to production tubing 78 by means of a coupling 79, the production tubing projecting from the lower end of the well packer A to the desired distance in the well casing therebelow. This tubing 78 will displace the flapper valve 32 from its seat 34, and hold it in the open condition shown in Fig. 1a.

The apparatus disclosed in the drawings is run in well casing with the parts occupying the relative positions shown in Figs. 1 and 1a. The upper and lower slips 22, of the well packer, as well as the packing sleeve 19, are in their retracted positions, the retaining sleeve 45 being disposed in its lowermost position along the body 10 to confine the setting slips 35 in a retracted position and enclose them completely. The coupling ring 72 is threaded to its full extent within the packer body 10, the lower end of the mandrel skirt 65 bearing against the upper end of the body 10. The apparatus is lowered in the well casing B by means of the tubing string C extending to the top of the hole, the downward force being transferred from the upper mandrel section 64 directly to the body 10, and, in view of the threaded

connection

48, 47 of the latter, with the retaining sleeve 45, shifting the retaining sleeve and the drag device 55 attached thereto in a downward direction, the drag blocks 59 merely sliding frictionally along the wall of the well casing B.

When the location in the well casing is reached at which the well packer is to be anchored in packed-off condition, it is merely necessary to rotate the tubular string C and the mandrel 63 connected thereto ina righthand direction. The packer body 10 and all of the parts therearound, with the exception of the retaining sleeve 45 and the drag device 55, will also rotate in a righthand direction, inasmuch as the retaining sleeve 45 has its rotation resisted by the drag blocks 59 of the drag device, to which it is connected. Such right-hand rotation causes the retaining sleeve 45 to thread relatively in an upward direction along the body 10 until the sleeve thread 47 becomes completely disconnected from the body thread 48, being disposed above the upper end of the latter (Fig. 4). When the lower end 49 of the sleeve moves above the setting slips 35, the latter are no longer held in a retracted position, the band 36 connected to the slips 35 tending to straighten out and expanding to en gage the slips 35 with the wall of the well casing B. It is desired to prevent the retaining sleeve 45 from moving upwardly to too great an extent. Accordingly, its upward movement is limited by engagement of the stop shoulder 52 at the lower end of the sleeve with the stop ring 53 mounted on the packer body 10.

After the setting slips 35 have engaged the casing, the tubular string C and the setting mandrel 63 are moved upwardly, such upward movement being transferred through the mandrel shoulder 77 to the coupling ring 72, and from the latter to the body 10 of the tool. All parts surrounding the body 10 below the auxiliary setting slips '35 move upwardly with the body, until the ex-.

pander portion 39 of the upper abutment 24 shifts up within the auxiliary slips 35, further wedging the latter outwardly into firm anchoring engagement with the wall of the well casing to hold the upper abutment 25 and slips 22 from moving upwardly to any further extent. Accordingly, a continuation of the upward movement of the tubular string C, mandrel 63 and packer body it) causes the screws 23 holding the upper slips 22 retracted to be. sheared, the upper expander then moving up-v wardly with the body 10. within these slips 22, to slide them radially outward along the upper abutment 24 and into anchoring engagement with the wall of the well casing B, in the manner described above. When the upper slips 22 become anchored to the wall of the wellv casing 13, they then prevent further upward movement of the upper expander 20, the upward force then being transmitted through such upper slips to the wallet the well casing, and, in elfect, relieving the setting slips 35 of the load, at least to a major extent. A continuation of the upward pull on the tubular string C, mandrel 63 and body 10 then shears the other packer screws, expanding the packing sleeve 19 against the well casing, and also the lower slips 15 against the well casing, as explained above.

A substantial upward pull can be taken on the tubular string C to insure a positive anchoring of the well packer A to the well casing against longitudinal movement in both directions, as well as a leakproof sealing of the packing sleeve or packing structure 19 against the wall of the well casing and against the periphery of the packer body 10. If assurance is desired that the well packer A will hold substantial loads in a downward direction, downweight may be imposed on thetubular string, such downweight being transferred through the upper section 64 of the setting mandrel to the body 10 of the tool, and through the ratchet ring 27 to the upper abutment 2d, the downweight then being conveyed through the upper slips 22, expander 20, packing sleeve 19, and lower expander 17 to the lower set of slips 15, that are anchored to the well casing against downward movement.

After it has been ascertained that the well packer A is firmly set in the well casing B, the tubular string C is rotated to the right, which will rotate the mandrel 63 in the same direction, such motion being transferred through the key 74 to the threaded coupling ring '72.

The latter will be threaded in an upward direction along the body head 11 until a complete unthreading is secured, because of the left-hand direction of the

threads

73, 13, the solid ring 72 moving upwardly into the cavity 76 between the intermediate mandrel section 66 and the skirt 65 of the upper section 64.

The tubular string C and mandrel 63 are now free rom connection with the well packer A. The tubing string and mandrel can now be shifted upwardly until a shoulder 80 on the upper mandrel section 64 engages the lower end of the drag sleeve 55. Since the retaining sleeve cannot move upwardly because of contact of its shoulder 52 with the stop ring 53 on the body 10, the taking of an adequate upward pull on the mandrel section 64 will cause the shear pin or screw 57 to be disrupted, allowing the drag device tomove upwardly with the tubing string C and mandrel 63 to the extent desired. It is preferred that the tubing string C and mandrel 63 be shifted upwardly to a substantial distance, which may, for example, be 30 to 90 feet, to avoid the danger of sand, or other settlings, from packing around the drag unit 55 and preventing its subsequent removal from the well casing.

Following the disconnection of the drag unit 55 and its upward movement in the well casing B to a point thereabove, such as disclosed in Fig. 6, the tubing string (2 and mandrel 63 can be relowered to bring the skirt 65 back into contact with the body 10 of the tool, in which relation the packing assembly 69 is appropriately disposed within the packer body 10 and in sealing contact with the inner wall 71 of the latter. The apparatus is now in the position disclosed in Figs. 6 and 6a, wherein production from the well below the packer A can be caused to pass upwardly into the tubing 78, continuing on through the tubular mandrel 63, and into the tubular string C.

If it is desired to remove the well packer A from the well casing, the tubular string C and mandrel 63 are elevated in the well casing, the shoulder on the mandrel engaging the drag unit 55 and lifting it along the well casing B to the top of the hole. All that will remain in the well casing will be'the well packer A itself and the auxiliary retaining sleeve 45. These parts can be removed through use of a suitable drill bit (not shown). When the drill bit is lowered on a drill pipe string (not shown) to the location of the packer A, and its rotation is started, the bit will first engage the upper end of the sleeve 45 and will cause its threads 47 to engage the body threads 48, the sleeve being rotated along the body 10 and fed downwardly by its threads 47 until its rotational stop pin 50 engages the vertical face 51 on the body, preventing further rotary movement of the sleeve 45. The drill bit can now operate upon the sleeve and effect its disintegration, after which the drill bit will operate upon the other portions of the well packer A to eltect their complete removal from the well casing, in a known manner.

It is preferred to have a substantial number of thread turns 48 on the packer body 10, to prevent inadvertent relative rotation between the body 10 and the retaining sleeve 45, while the apparatus is being lowered in the well bore, to the extent at which the setting slips 35 may be released and their expansion against the well casing permitted. With about fifteen threads 48 on the body and with the sleeve threadedly engaging the lowermost thread, about fifteen turns are required of the body 19 before the sleeve 45 is shifted upwardly to a slip releasing location.

It is also desired to have one or twotthreads 47 on the sleeve 45 engage the threads 48 on the body as a precautionary measure. The type of well packer disclosed may be set by other equipment than specifically disclosed. One such type of equipment merely exerts a downward force on the sleeve 45 and an upward pull on the body 19. If such equipment is used, the one or two threads 47 on the sleeve will be sheared without difliculty, permitting the appropriate downward movement of the sleeve 45 and relative upward movement of the body 10 to occur, to secure full anchoring in packed-oft condition of the well packer against the well casing.

It is, accordingly, apparent that apparatus has been provided which permits the tubular string C to lower the apparatus in the well casing, mechanical actuation of the tubular string efiecting a full setting of the well packer A as a result of first rotating the tubular string and then taking an upward pull thereon, the tubular string remaining in operative relation with the well packer so that it can function to conduct the production from the well bore to the top of the hole. All of these results are accomplished with a single trip of the apparatus in the well casing. It is not necessary to first lower the well packer A on a running-in string in the well casing B, the packer then being anchored in packed-oft condition,

after which the tubular string C must be withdrawn from I the well casing and another tubular string, or the same tubular string, relowered in the well casing and once again operatively associated with the well packer.

The inventor claims:

1. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted means thereon adapted to be expanded outwardly against the conduit string in response to longitudinal movement of the body in the conduit string; holding means adapted to be held in anchored position against the conduit string by said normally retracted means to prevent longitudinal movement of said normally retracted means and enable longitudinal movement of said body to expand said normally retracted means; means disposed laterally outwardly of said holding means and engageable therewith for initially retaining said holding means in a retracted position and preventing its outward movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in'response to movement of said body; and means for expanding said holding means against the conduit string upon release of said retaining means from said holding means.

means 2. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having slip means thereon adapted to be expanded outwardly against the conduit string in response to longitudinal movement of the body in-the conduit string; holding means adapted to be held in anchored position against the conduit string by said slip means to prevent longitudinal movement of said slip means and enable longitudinal movement of said body to expand said slip means; means engageable with said holding means for initially retaining said holding means in a retracted position and preventing its outward movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expanding said holding means against the conduit string upon release of said retaining means from said holding means.

3. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted means thereon adapted to be expanded outwardly against the conduit string in response to upward movement of the body in the conduit string; holding means above said normally retracted means adapted to be held in anchored position against the conduit string by 'said normally retracted means to prevent upward movement of said normally retracted means and enable upward movement of said body to expand said normally retracted means; means disposed laterally outwardly of said holding means and engageable therewith for initially retaining said holding means in a retracted positionand preventing its outward movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expanding said holding means against the conduit string upon release of said retaining means from said holding means.

4. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having slip means thereon adapted to be expanded outwardly against the conduit string in response to upward movement of the body in the conduit string; holding means above said slip means and adapted to be held in anchored position against the conduit string by said slip means to prevent upward movement of said slip means and enable upward movement of said body to expand said slip means; means engageable with said holding means for initially retaining said holding means in a retracted position and preventing its outward movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expanding said holding means against the conduit string upon release of said retaining means from said holding means.

5. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted means thereon adapted to be expanded outwardly against the conduit string in response to the longitudinal movement of the body in the conduit string; holding means adapted to be held in anchored position against the conduit string by said normally retracted means to prevent longitudinal movement of said body to expand said normally retracted means; means including drag instrumentalities frictionally engageable with the conduit string and engageable with said holding means for initially retaining said holding means in a retracted position and preventing its outward movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expanding-said holding means against the conduit string A by said normally retracted means gageable with the conduit .said holding means for initially retaining saidholding txmeans in retracted position and preventing its outward conduit string in responseato.longitudinal movement of the body in the conduit-string; holding means adapted to be. held in anchored position against the/conduit string by said slip means to prevent longitudinal movement of said slip means and enable longitudinal movement of said body to expand said slip.-rneans; means including drag instrumentalities frictionally engageable, with the conduit string and engageable with said holding means for initially retaining said holding means in retractedposition and preventing its outward movement into engagement with the-conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expandingsaid holding means against; the conduit string upon release of said retaining means from said holding means.

7. In subsurface well apparatus to be set ina conduit stn'ng disposed in a well bore: a body having normally retracted means thereon adapted to be expanded outwardly against the conduit string in response to upward movement of the body in the conduit string; holding means above said normally retracted means adapted to be held in anchored position against the conduit string to prevent upward movement of said normally retracted means and enable upward movement of said body to expand said normally retracted means; means including drag instrumentalities frictionally engageable with the conduit string andengageable with said holding means for initially retaining said holding means in retracted, position and preventing its outward movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expanding said holding means against the conduit string upon release of said retaining means from said holding means.

8. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having slip means thereon adapted to be expanded'outwardlyagainst the conduit striugin response to upward movement of the body in the conduit string; holding means above said slip means and adapted to be held in anchored position against the conduit string by said slip means to prevent upward movement of said slip means and enable upward movement of said body to expand said slip means; means including drag instrumentalities frictionally enstring and. engageable with movement into engagement with the conduit string; means for releasing said retaining means from said holding means and for elevating said retaining means above said holding means in response to movement of said body; and means for expanding said holding means against the conduit string upon release of said retaining means from said holding means.

9. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted upper slips thereon to anchor the body to the conduit string against upward movement; an expander movable upwardly with said body to expand said upper slips outwardly; setting slips above said upper slips; expander means between said upper slips and setting slips to hold said setting slips against the conduit string and to prevent upward movement of said upper slips; and means engageable with said setting slips for holding said setting slips initially in retracted position and releasable from said setting slips in response. to; manipulation of said body.

irnally. retracted slips thereon to anchor the body to. the

,conduit string against longitudinal-movement; anexpander movable with said body to expand said slips outwardly; setting slips disposed to one side of said normally retracted slips; expander means between said normally retracted slips and setting slips to hold saidsetting slips against'theconduit string to prevent longitudinal movement ofsaid normally retracted slips; and means engageable withsaid setting slips for holding said settingslips initially in retracted. position and releasable from said setting slips in.response tomanipulation'of said body.

11. In subsurface well apparatus to .be set in a conduit string disposed in a well bore: a body having normally retracted slips thereon to anchor the body to the conduit stringagainst longitudinal movement; an .expander movable with said body to expand-said slips outwardly; setting slips disposed to one side of said normally retracted-slips; expander means between said normally retracted slips and setting slips to. hold said setting slips against the conduit string to prevent longitudinal movement of said normally retracted slips; and means including drag instrumentalities frictionally engageable with the conduit string .and engageablewithsaid setting slips for holding said setting slips initially in a retracted position, said holding means being releasable from said'settingv slips in response to manipulation of said body;

12. In subsurface well apparatus to be set'in a conduit string disposed in a Well bore: a body having. normally retracted upper slips thereon to anchor the body to the conduit string againsteupward movement;an, expander movable upwardly with said body to expand said upper slips outwardly; setting slips above said upper slips;

expander means. between said-upper slips and setting slips to hold said setting slips against the conduit string and to prevent upward movementof said upper slips; a sleeve encompassing.saidsetting slips to hold them initially inretracted position; means connected to said sleeve'to resist its movement in the conduit string; and means connected to said body and sleeve to release said sleeve from said setting slips inresponse to manipulation of said body.

13.In subsurfacewell apparatus to be set in a-conduit string disposed in a well bore: a, body having normally retracted slips thereon to anchor the body to the conduit string against. longitudinal movement; an expander movable with said body to expand said slips outwardly; setting slips disposed to one side of said normally retracted slips; expander means between said normally retracted slipsand setting slips to hold said setting slips against the conduit stringto prevent longitudinal movement .of-said normally retracted slips; asleeve en- 1 compassing said settingslips to .hold them'initially. in

retracted position; means connected to said sleeve to resist its movement in the conduit string; and means connected to said body and sleeve to release said sleeve from said setting slips in response to manipulation of said body.

14. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted upper slips thereon to anchor the body to the conduit string against upward movement; an expander movable upwardly with said body to expand said upper slips outwardly; setting slips above said upper slips; expander means between said upper slips and setting slips to hold said setting slips' against the conduit string and to prevent upward movement of said upper a sleeve encompassing said setting slips to hold them initially in retracted position; means connected to said sleeve to resist its movement in the conduit string;

and means providing a threaded connection between said body and sleeve for elevating said sleeve relatively along said body and releasing said, sleeve vfrom said setting slips in response to rotation of said body 15. In subsurface well apparatus to be set in a conduit string disposed in a well bore: abody having normally retracted slips thereon to anchor the body to the conduit string against longitudinal movement; an expander movable with said body to expand said slips outwvardly; setting slips disposed to one side of said normally retracted slips; expander means between said normally retracted slips and setting slipsto hold said setting slips against the conduit string to prevent longiudinal movement of said normally retracted strips; a sleeve encompassing said setting slips to hold them initially in retracted position; means connected to said sleeve to resist its movement in the conduit string; and means providing a threaded connection between said body and sleevelto move said sleeve longitudinally with respect to said body and release said sleeve from said setting slipsin response to rotation of said body.

16. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted upper slips thereon to anchor the body to the conduit string against upward movement; an expander movable upwardly with said body to expand said upper slips outwardly; setting slips above said upper slips; inherently expansible means connected to said settingslips and tending to expand said setting slips against the conduit string; expander means between said upper slips and setting slips to hold said setting slips against the conduit string and to prevent upward movement of said upper slips; and means engageable with said setting slips for holding said setting slips initially in retracted position and releasable from said setting slips in response to manipulation of said body. 7

17. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted slips thereon to anchor the body to the conduit string against longitudinal movement; an expander movable with said body to expand said slips outwardly; setting slips disposed to one side of said normally retracted slips; inherently expansible means connected to said setting slips tending to expand said setting slips against the conduit string; expander means between said norm-ally retracted slips and setting slips to hold said setting slips against the conduit string to prevent longitudinal movement of saidnormally retracted slips; and means engageable with said setting slips for holding said setting slips initially in retracted position and releasable from said setting slips in response to manipulation of said body. r

18. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted upper slips thereon to anchor the body to the conduit string against upward movement; an expander movable upwardly with said body to expand said upper slips outwardly; setting slips above said upper I2 slips; inherently expansible means connected to said setting slips and tending to expand said setting slips against the conduit string; expander means between said upper slips and setting slips to hold said setting slips against the conduit string and to prevent upward movement of said upper slips; a sleeve encompassing said setting slips to hold them initially in retracted position; means connected to said sleeve to resist its movement in the conduit string; and means connected to said body and sleeve to release said sleeve from said setting slips in response to manipulation of said body.

19. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retraced upper slips thereon to anchor the body to the conduit string against upward movement; and expander movable upwardly with said body to expand said upper slips outwardly; setting slips above said upper slips; inherently expansible means connected to said setting slips and tending to expand said setting slips against the conduit string; expander means between said upper slips and setting slips to hold said setting slips against the conduit string and to prevent upward movement of said upper slips; a sleeve encompassing said setting slips to hold them initially in retracted position; means connected to said sleeve to resist its movement in the conduit string; and means providing a threaded connection between said body and sleeve for elevating said sleeve rela tively along said body and releasing said sleeve from said setting slips in response to rotation of said body.

20. In subsurface well apparatus to be set in a conduit string disposed in a well bore: a body having normally retracted slips thereon to anchor the body to the conduit string against longitudinal movement; an expander movable with said body to expand said slips outwardly; setting slips disposed to one side of said normally retracted slips, inherently expansible means connected to said setting slips and tending to expand said setting slips against the conduit string; expander means between said normally retracted slips and setting slips to hold said setting slips against the conduit string to prevent longitudinal movement of said normally retracted slips; a sleeve encompassing said setting slips to hold them initially in retracted position; means connected to said sleeve to resist its movement in the conduit string; and means providing a threaded connection between said body and sleeve to move said sleeve longitudinally with respect to said body and release said sleeve from said setting slips in response to rotation of said body.

References Cited in the file of this patent UNITED STATES PATENTS 1,919,853 Mack July 25, 1933 2,178,999 Scott Nov. 7, 1939 2,323,085 Davis June 29, 1943 2,600,468 Breaux June 17, 1952 2,765,853 Brown Oct. 9, 1956