US3054451A

US3054451A - Well apparatus

Info

Publication number: US3054451A
Application number: US671212A
Authority: US
Inventors: James W Bonner
Original assignee: LOWREY OIL TOOLS Inc
Current assignee: LOWREY OIL TOOLS Inc
Priority date: 1957-07-11
Filing date: 1957-07-11
Publication date: 1962-09-18
Anticipated expiration: 1979-09-18

Description

J. w; BONNER WELL APPARATUS Sept. 18, 1962 7 Sheets-Sheet 1 Filed July 11, 1957 INVENTOR Ii, i

ATTORNEY P 13, 1962 J. w. BONNER 3,054,451

WELL APPARATUS Filed July 11, 1957 7 Sheets-Sheet 2 52 25 52 c/amew" l l flan/7 er INVENTOR.

ATZOR/VEV J. W. BONNER WELL APPARATUS Sept. 18, 1962 7 Sheets-Sheet 4 Filed July 11, 1957 James W 50/70 6/ INVENTOR.

fifty O ZN? Ck ATTORNEY p 18, 1962 J. w. BONNER 3,054,451

WELL APPARATUS Filed July 11, 1957 7 Sheets-Sheet 5 //6 E //3 k; 51 E A i i /5 i A #2 James 14/. Banner INVENTOR.

ATTORNEY J. W. BONNER Sept. 18, 1962 WELL APPARATUS 7 Sheets-Sheet 6 Filed July 11, 1957 c/ames l/V. Bonner INVENTOR.

ATTORNEY Sept. 18, 1962 J. w. BONNER WELL APPARATUS 7 Sheets-Sheet 7 Filed July 11, 1957 (/0079: W fiofifler INVENTOR.

ATTORNEY fd States atent ce 3,054,451 Patented Sept. 18, 1962 3,054,451 WELL APPARATUS James W. Bonner, Houston, Tex., assignor of one-half to Lowrey Oil Tools, Inc., Houston, Tex., a corporation of Texas Filed July 11, 1957, Ser. No. 671,212 21 Claims. (Cl. 166-123) This invention pertains to well apparatus and more particularly to devices such as well packers, and bridging plugs and means for setting and retrieving and for connecting to and disconnecting from same.

An object of the invention is to provide such a device and means whereby the device can be set in a well independent of pipe weight yet which can be retrieved whenever desired. The term pipe is used throughout in its generic sense which includes tubing and casing.

A further object of the invention is to provide such a device and means whereby the device can be run and set and retrieved with pipe or with a wire line or can be run and set with a wire line and retrieved or reset with pipe.

Another object of the invention is to provide a retrievable well packer which can be run and set with either a wire line or pipe and to which the production tubing can be connected and disconnected at will.

Another object of the invention is to provide a well device having both upper and lower slip type anchors in which the lower anchor can be set before the upper anchor and then the upper anchor can be set and maintained in place independent of the means by which the device was lowered into the well.

Another object of the invention is to provide an improved holddown anchor for packers and the like.

Other objects and advantages of the invention will appear as the disclosure thereof proceeds, reference being made to the accompanying drawings wherein FIGURES 1A through 1D together show a vertical half section through a complete well packer adapted to be run on tubing;

FIGURE 1E is a horizontal section on line 1E1E of FIGURE 1C;

FIGURE 2 is a horizontal section on line 2-2 of FIGURE 1;

FIGURES 3, 4, and 5 are schematic views showing the operation of the packer shown in FIGURES lA-lD.

FIGURES 6A and 6B show a half section through a means for releasably sealing and connecting to the top of a device in accordance with the invention;

FIGURE 6 is a vertical half section through the connected means of FIGURES 6A and 6B;

FIGURE 7 is a horizontal section taken on line 77 of FIGURE 6;

FIGURE 8 is a vertical half section showing a gas type setting tool connected to the top of a device made in accordance with FIGURE 6B;

FIGURE 9 is a vertical half section through the bottom of a device according to the invention suitable for running on a wire line;

FIGURE 10 is a vertical half section through the bottom of a device according to the invention suitable for running on a wire line and repositionable with tubing;

FIGURES 11-13 are schematic views showing the operation of a device according to the invention run on a wire line.

By way of introduction, and referring to the schematic drawings (FIGURES 3-5 and 11-13) it may be said that the invention contemplates a sub A connectable at its upper end to a tubing string 21 (FIGURES 3-5 and 13) or a wire line 148 (FIGURES 11-12) for lowering the device of the invention into a well and for removing it therefrom or relocating it therein. The lower part of the sub telescopes over the upper part of a pipe forming the upper end of an elongated inner member IM extending down the length of the device, said parts together with suitable stops thereon constituting means connecting the sub to the inner member for limited relative longitudinal motion thereof. The sub is splined to the inner member providing means to transmit rotation thereto. The aforementioned telescopic and splined connection between the sub and intermediate member are together identified by reference number I.

The sub also carries a resilient split prestressed sleeve which frictionally engages around the outer portion of a mandrel forming a part of the inner member, the sleeve and outer portion of the mandrel forming resilient friction means 11 connecting the sub and inner member preventing relative longitudinal motion thereof in either direction except upon the exertion of a certain force. Preferably the mandrel is provided with a thread on its outer portion whose upper flank lies at an angle to the axis of the mandrel, the flank flaring downwardly, and the sleeve is correlatively internally threaded. The resilient means provided by the mandrel and sleeve resist longitudinal relative motion of the sub and inner member but allow such motion if enough force is exerted. If the engaging surfaces of the mandrel and sleeve are plain unthreaded cylindrical surfaces, only enough force need be exerted to overcome the friction therebetween. If the mandrel and sleeve are threaded as described above the friction increases as the sleeve moves down the mandrel.

A slip type anchor means III connects the sub to the mandrel. This includes a slip expander cone or wedge body and a set of slips in a slip cage. According to the preferred embodiments the slip expander is connected to the sub and the caged slips are connected to the inner member. On relative axial motion of the sub and inner member the slips are expanded. The direction of the taper of the surface of the expander is such as to flare upwardly, i.e., convenge downwardly, so that the anchor serves as a hold down anchor relative to the inner memher.

The remainder of the device below the hold down anchor forms a hook wall packer. The packer includes a sealing material sleeve IV concentrically disposed around the inner member and having its upper end engaging a downwardly facing surface on an abutment B fixed on the inner member and having its lower end engaging an upwardly facing surface on an abutment C slidable on the inner member.

The sliding abutment C is connected to the upper end of a second slip type anchor means V including a slip expander and caged slips. The lower end of the second slip type anchor means is connected to a support means D which takes different forms in the difierent embodiments as will appear later on, e.g. a tubular member which may or may not have drag block windows and may or may not carry a shear pin engaging the draw bar of a wire line setting tool. According to the preferred embodiments of the invention the slip expander is connected to the sliding abutment C and the caged slips are connected to the support means D. The direction of the taper of the surface of the expander is such as to flare upwardly, i.e., converge downwardly so as to provide a hold up anchor for the sleeve.

The support means D is merely a force transmitting means; a thrust means, e.g. drag blocks VI and/ or setting tool piston 151 is provided through which is developed an upward thrust to be exerted on the support means D and transmitted by the latter to the anchor. A resisting means is provided to hold the support means D against premature axial motion relative to the sliding abutment C until it is desired to set the lower anchor.

If the device is to be run on tubing only, as shown in FIGURES 3-5, the support means D for exerting an axial force against the anchor is provided by a drag block housing, the thrust generating means includes drag blocks VI mounted .in the housing and adapted to frictionally engage the well casing and thus generate a reaction force as needed; and the resisting means to hold the support means against premature setting motion comprises a J-slot and pin 101.

If the device is to be run and set on a wire line initially but capable of thereafter being released, relocated, and reset on tubing, as illustrated in FIGURES 11-13, the

support D will include further a shear pin 185 and the thrust means for generating a force against support means D.will further include piston 151 which acts through a draw bar 153 extending through the tubular inner member and connecting to the shear pin 185. The draw bar, by its weight, will act as a resisting means to prevent premature setting of the device, supplementing the J -slot and pin 101.

If the device is merely to be run on a wire line, the arrangement would be similar to that shown in FIGURES 11-12 except that the drag blocks would be omitted and so Wouldthe J-slot and pin 101.

' For a detailed description of the invention reference will now be made to the other figures of the drawings.

Device (Well Packer) Run on Tubing end of a string of tubing 21. The sub further comprises a pipe 22 connected to the lower end of nipple 20 and a pipe 23 connected to the lower end of pipe 22. An embodiment of the previously referred to inner member axial load acting through the wedges formed by the correlative buttress

threads

41 and 44 on the mandrel and nut is suflicient to create a force tending to expand the nut equal to that which was necessaryto assemble the nut initially. After such equality of forces is reached, further axial loading (or if the spring nut is not preloaded the initial axial loading) causes relative movement of nut and mandrel but against the constantly increasing frictional resistance of the nut as its thread slides on the mandrel thread due to the expansion of the nut. The successive turns of the upper flank of the mandrel thread and the lower flank of the nut provide the mandrel with a continuous succession of tapered portions; the taper is sufiiciently within the angle of repose so that the nut does not return to its initial position upon release of the axial loading but requires a large reverse axial loading to return it to its original position. The precise angle will depend upon the coefficient of friction between the thread surfaces, the available space for the thread, and the desired ultimate loading of the packer sleeve as hereinafter set forth.

The nut 42 is held to sub 20 between the lower end of pipe 22 and a shoulder on pipe 23 with sufficient radial clearance to allow it to expand as needed. The cross sectional shape of the nut, thickest opposite the split, is such as to give maximum strength with suificient clearance for expansion as needed.

The lower end of pipe 23 is connected to pipe 50. Referring now to FIGURES 1C and 1E, a generally cylindricai wedge body 51 is formed on the lower end of pipe 50. The wedge body constitutes a slip expander means. The wedge body 51 has four longitudinal grooves therein of increasing depth progressing downwardly. The bottoms of the grooves provide four flat faces 52 disposed at right angles to each other. A slip cage 53 having four openings 54 is formed on a nipple 55 connected to mandrel 25 and forming a continuation of the inner member. Nut 56 screwed into the upper end of the cage forms a stop to engage shoulder 57 on the wedge body to limit relative axial motion in the unsetting direction of the relative motion of the slip cage and wedge body. The

I slip cage provides a means for mounting the slips 58 pro- IM comprisesa pipe 24 to the lower end of which is viding for radial in and out motion while preventing longitudinal motion thereof. Four slips 58 disposed in the openings 54 in the slip cage, have flat backs 59 to engage the wedge body and cylindrical front faces with wickers 60 thereon to engage a well casing. FIGURE 2 shows the relative position of a well casing 61. Referring now especially to FIGURE 1E, each slip has grooves 62 on its sides engaging tongues 63 on the sides of the grooves in the wedge body. Referring again to FIGURE 1C,

' downward motion of the Wedge body relative to the slip of such slots and keys may be used. This connection, an embodiment'of the previously referred to means I,

allows limited relative longitudinal movement of the parts and prevents relative rotation thereof. Chevron packing 33 provides a sliding .seal between the inner member and pipe 22 of the sub.

Refer-ring particularly to FIGURE 1B, the mandrel 25 hasa downwardly facing buttress thread 41 formed thereon which together with split nut 42 forms an embodiment of the previously referred to resilient frictional means 11 for connecting the sub to the inner member for longitudicages forces the slips radially outward to engage the well casing. Upward motion of the wedge body relative to the slip cage draws the slips radially inward away from the well casing. The wedge body, slips and cage form an embodiment of the previously referred to slip type anchor means III connecting the subwith the inner member. 7

A pipe 69 is connected to the lower end of nipple 55. Also connected to the lower end of nipple 55 is a pipe 70 forming a further continuation of the inner member. Slidably mounted on pipe 70 is a mandrel 72 which together with ring 75 forms a sliding abutment. A sleeve 73 of sealing material such' as synthetic rubber is disposed on mandrel 72 and is thus concentric with pipe 70. The sleeve is disposed between end rings 74, 75, the latter resting on a shoulder on mandrel 72. Ring 74 is screwed into the lower end of pipe 69 and also forms a stop cooperating with'a nut 76 screwed onto the upper end of mandrel 72 to limit relative longitudinal motion of the mandrel and pipe 69 in the sleeve unsetting (relaxing) direction. Ring 74 forms a fixed abutment and provides a downwardly facing surface engaging the upper end of sleeve 73. Ring 75 provides an upwardly facing surface engaging the lower end of sleeve 73. Downward motion of pipe 6?, relative to mandrel 72 compresses the sleeve 73 am'ally, causing it to expand radially into sealing engagement with the casing and with mandrel 72 and with ring 74. Ring 74 is in fluid tight relationship with the inner member through its connection to pipe 69 and nipple 55. Pipe 69 and ring 74 form an embodiment of the previously referred to abutment B, sleeve 73 forms an embodiment of sealing material sleeve IV, and mandrel 72 with ring 75 forms an embodiment of the previously referred to sliding abutment.

Referring now to FIGURE 1]), a four sided wedge body 80, which constitutes a slip expander means similar to wedge body 51, is connected to the lower end of mandrel 72. Means forming a sliding seal between the wedge body and the pipe 7% comprises downwardly facing chevron packing 81. A member 82 forming a sup port means to exert an axial force is slidably mounted on the inner member formed at this level by pipe 70. A slip cage 83 is rotatably connected to the upper part of member 82 by means of pins 83A through the cage engaging annular groove 32A in member 82. Cage 83 has four openings 84 in which are mounted four slips S5. The backs of the slips are flat to engage the flat faces of the wedge body. Interengaging tongues on the Wedge body and grooves in the slips are provided as for slips 58 and wedge body 51, this construction being also used in all the slip type anchors hereinafter described. The outer faces of the slips are cylindrical and provided with wickers 36 to engage the well casing. A nut 87 screwed into the upper end of the slip cage forms a stop cooperating with a shoulder 88 on the wedge body to limit relative longitudinal travel of the slip cage and wedge body in the slip unsetting direction. Downward movement of the wedge body relative to the slip cage forces the slips radially outward into engagement with the casing. The slips, cage, and wedge body form an embodiment of the previously referred to slip type anchor means V connecting the sliding

abutment

72, 74 to the support means 82, the latter respectively forming embodiments of the previously referred to sliding abutments C and support means D.

There is provided an embodiment of the previously referred to thrust means VI for exerting an upward thrust against the support means $2, such means comprising in this embodiment of the invention four casing engaging friction drag blocks 91'). Each drag block is set in a recess 91 in the member 82, being retained therein by the upper and

lower edges

2, 93 respectively of windows in a skirt 94 connected to member 82. A plurality of helical compression springs 93 bias the drag blocks outwardly into casing engagement.

An embodiment of the previously referred to means resisting axial movement of the support means D relative to the sliding abutment C includes in the FIGURES 1A5 construction, a releasable locking means to hold the inner member and support means 82. axially stationary relative to each other, thereby to prevent setting of the packer sleeve and lower slips until desired. The releasable locking means includes a collar Ititl screwed on to the lower end of pipe 7% and having a pin 101 screwed therein. Skirt 94 has an inverted J shaped slot 132 therein thus completing a J-slot type of lock. By rotating the inner member while the drag blocks keep the support means 32 from rotating, the pin on the inner member may be moved from the curved part of the J-slot into the straight vertical part thereof in which downward motion of the inner member relative to support means 82 becomes possible, the latter being held stationary by the drag blocks.

Referring now to FIGURES 3-5 there is depicted in sequence the operation of setting the device of FIGURES lA-lE and 2. In FIGURE 3 the device is shown going into the well indicated by casing 61. On the inner member, there are disposed the upper anchor III, sealing sleeve IV, and lower anchor V; all are in the unset position. The resilient friction means II holding the sub A against longitudinal motion relative to the inner member IXI has not allowed any motion, and the pin 101 of the J-slot connection of the resisting means for holding support means 82 in the locked position. By rotating the inner member through the key and slot connection, from sub A, which is connected to the tubing string 21, the J-slot is unlocked. Then downward motion of the tubing string moves the parts into the position shown in FIGURE 4 in which the packer sleeve and lower slips are set. Further lowering of the tubing overcomes the resistance of the split nut means and causes the upper anchor to set as shown in FIGURE 5.

Ratchet Thread Connector and Seal Referring now to FIGURES 6A, 6B, 6 and 7, there is shown an alternative means for connecting and disconnecting the tubing string 21 to the sub A. Such means on the sub A comprises a special socket portion which is adapted to receive a special pin portion connected to the string 21.

Referring now to FIGURES 6A and 6, the pin portion comprises a reduction nipple connected at its upper end to the string 21 and a mandrel 111 connected to the lower end of the nipple 110. At the lower end of the mandrel is mounted means for making a sliding seal with the socket comprising chevron packing 112 having portions facing both upwardly and downwardly. Above the packing 112 is slidably mounted a sleeve 113 limited in its longitudinal motion relative to the mandrel by

stop shoulders

114, 115 on the nipple and mandrel respectively. The exterior of the upper part of mandrel 111 is hexagonal as shown in FIGURE 7, and the interior of sleeve 113 is similarly shaped. Relative rotation of these parts is thus prevented. Disposed in recesses 116 in the sleeve are a plurality of threaded segments 117. The segments are limited in this outward movement by

flanges

118, 119 on the sleeve. Helical compression springs 1219 urge the segments outwardly. The segments are formed as portions of a pipe having a continuous upwardly pointing buttress thread.

Referring to FIGURE 6B, the sub A is provided at its upper end with a socket which comprises a pipe The interior of pipe 136 is smooth to engage and seal with packing 112 of the pin in any relative position. To

- the upper end of pipe 136 is connected a pipe 131 forming a continuation of the socket and having an internal thread 132 correlative to that of the pin shown in FIG- URE 6A.

The pin can be stabbed into the socket, as shown in FIGURE 6, when it is desired to connect the tubing string 21 to a well packer already set in the well. The threaded segments 117 ratchet over the thread 132 on the interior of pipe 131. The packing 112 seals with pipe 130. The string is then free to move axially up and down as it expands and contracts within the limits imposed by

stops

114, 115 on sliding of the sleeve 111 carrying the threaded segments, but complete separation is prevented by the engagement of the threaded segments with the threaded pipe 131. During such motion a seal is at all times maintained. This connection therefore also constitutes an expansion joint. When it is desired to disconnect the pin and socket the tubing string is rotated to unscrew the threaded segments from the threaded pipe. Usually the threads 132 will be left-handed.

The connection just described with reference to FIG-

URES

6A, 6B, 6 and 7 can be used with the packer of FIGURES lA-lE and 2 whenever it is desired that the tubing be releasable from the packer or that an expansion joint be provided in the connection between tubing and packer. The device may be the same as shown in FIG- URES lA-lE and 2 except for the connection between the sub A and the tubing string. The lower end of pipe 130 (FIGURE 6B) will screw into the top of nipple 20 (FIGURE 1A) instead of tubing 21, the tubing 21 being screwed into the top of nipple 110 (FIGURE 6A) Howi "7 ever the more usual use will be in connection with a well packer or other device which is to be run into position on a wire line and thereafter to be connected to a string of tubing.

Wire Line Setting Tool as shown in FIGURES 1A-1E and 2 except that the upper end will be modified to include the releasable tubing connection of FIGURES 6 and 7 and the bottom end will be modified as shown in FIGURE 9 or 10. FIG- URE 8 shows a suitable wire line setting tool connected to the upper end of such a' modified device.

Referring to FIGURE 8 there is shown a wire line 148 carrying a conventional setting tool 149 comprising a cylinder 150 in which moves a piston 151. Piston 151 forms another embodiment of the thrust means which in the embodiment of FIGURES lA-Z took the form of drag blocks 90. Gas is admitted to the cylinder when desired through ports 152 in the piston rod or draw bar 153. The gas is supplied from a compressed gas cylinder in the upper part of tool 149, being released to the cylinder when desired by opening of the electric actuated valve shown at the upper end of the passage leading to the piston rod. For a fuller description of the operation of the setting tool reference may be made to page 2758 of the 1954-55 edition of the Composite Catalogue of Oil Field and Pipe Line Equipment published by the Gulf Publishing Company.

The cylinder 150 is connected to a pipe 160 which rests against shoulder 161 formed at the junctures of

pipes

130 and 131 of the tubing connection. The draw bar 153 extends down through the interior of the inner member (designated IM). Continuing through parts of the device like those shown in FIGURES 1 and 2 to the modified bottom thereof, the draw bar 153 is shown again in FIGURE 9. 7

Device (Bridge Plug) Run on Wire. Line As shown in FIGURE 9, member 182 corresponding to support means 82 is'modified to omit the recesses that in the corresponding member 82 in FIGURE 1D con? tained friction drag blocks and is screw connected .to the slip cage 183 instead of being freely rotatably connected thereto as in FIGURE 1D. Also, the SJ-slet skirt connected to the support means 82 in the FIGURE 1D embodiment is omitted and the member182rests directly on top of collar 200 screwed on to the lower end of the inner member 70. The inner member has a slot 170 ex- 7 tending longitudinally up from its lower end. 7 A screw plug 184 extends through slot 170. .Plug184 has a shear pin 185 therein which engages extension 186 on draw bar 153. By virtue of this connection support 182 carrying the slip cage does not move except with the draw bar until pin 185 shears. The weight of the draw bar and piston keeps the slip cage out' of setting engagement with the slips until the setting tool is actuated. A bull plug 187 in the bottom of nipple 183 converts the device from a well packer to a bridging plug.

The operation of the device modified as described is as follows. The draw bar thus forms another Vembodi ment of the resisting means which in the embodiment of the FIGURES 1A2 took the form of pin 101 and slot 102. The device is lowered into the well on a wire line. The gas is released to the cylinder of the setting tool cansing the draw bar to move up, causing the support means (member 182) to move up relative to the inner member, thus starting to set the lower slips and the sealing sleeve. When a certain amount of resistance is created by the slips engaging the casing, the cylinder of the setting tool carrying the sub A and the inner member starts to .move down (there being enough stretch to the wire line to allow this). The lower slips and the sealing sleeve are thus set and the inner member held stationary. Further downward motion of the cylinder overcomes the resilient friction means and sets the upper slips. Finally pin 185 shears and the setting tool can be removed. The bridging plug remains set due to the resistance of the resilient friction means (split nut). When it is desired to remove the plug it can be removed either with a wire line spear engaged with the threaded socket 131 or with a string of tubing provided with a ratchet threaded pin as in FIG- URE 6A. In this construction the seal 112 and seal nipple or pipe .130 of FIGURES 6A and 613 can be omitted since there is no need to make a sealing engagement with the tubing or wire line spear. Also the hexagonal sleeve can be omitted and the threaded segments could be mounted directly on the mandrel.

Device (Packer) Run on Wire Line and Resettable With Tubing If it is desired to set a well packer on a wire line, as distinguished from a bridging plug as just discussed, the seal 112 and the seal nipple of the tubing connection will be retained and the modified bottom shown in FIGURE 10 will be used.

Referring to FIGURE 10, the member 82 forming the support means is the sameas in the FIGURE 1D embodiment of the invention, being freely rotatably connected at its upper portion to slip cage 83 by means of pins 83A engaging annular groove 82A as in FIGURE 1D. 'Member 82 is likewise recessed to receive drag 'blocks 90.' A skirt'member 294 somewhat similar to member 94 of the FIGURE lD embodiment is connected to the lower portion of member 82. Member 294 has a screw plug 184 therein which, like plug 184 of FIGURE 9, carries a shear pin 185 which engages extension 286 on the draw bar 153. Inner member 70, as in the FIGURE 9 embodiment, is provided with a slot therein. A collar 300 is screw connected to the lower end of the inner member 70. Collar 300, like collar 1000f FIGURE 1D, carries a pin 101 moving in J-slot 102 of skirt 294. Collar 300 diffens from collar 101) in that the former is provided with a slot 290. Plug 184 extends through

slots

170 and 290. A shear pin 287 passing through the inner member holds the drag blocks to the draw bar extension 286 so they cannot cause the draw bar to be elevated relative to the inner member while the device is being lowered into the well. Pin 101 carried by the inner member and cooperating with J-slot 102 in member 294 is ineffective for this purpose since the pin initially must be in the straight part of the slot when the device is run on a wire line.

To set the well packer device of FIGURE 10, the device is run in the well on a wire line to the desired position as shown in FIGURE 11. Then the gas in the setting tool is released causing the draw bar to elevate the support means (member 82) relative to theinner member through the shear pin and member 294 until the slip cage carried by member 82 moves the slips 85 up on the wedge body 813 enough to partially set the slips 85. Then the cylinder of the setting tool forces sub A and inner member down to finish setting the lower slips and the packer sleeve. During the period of relative motion of the inner member and support means 82 pin 287 is sheared freeing the drag blocks, but the plug 184 moves up through slot 290 in the inner member and slot 170 in collar 30%), and slot 102 moves up around pin 101. Then the inner member is held stationary in the well and the final setting takes place when the force of the setting tool overcomes the resistance of the resilient friction means and forces sub A down relative to the inner member setting the upper slips. Thereafter further relative motion of the piston and cylinder-0f the setting tool shears pin 185 freeing the setting tool. This is the condition shown in FIGURE 12. The setting tool can then be removed and tubing connected to the packer, the

9 same as previously described in connection with the bridge plug of FIGURE 9.

FIGURE 13 shows a tubing string 21 connected to the upper end of the FIGURE device as in FIGURE 6. If it is desired to retrieve the packer it is only necessary to pull up on the tubing string. If it is desired to set the packer at a lower position a left-hand rotation sufficient to engage the J-slot to hold the drag blocks to the inner member enables the device to be lowered without setting. Then the J-slot can be freed by a right-hand rotation and the packer reset. The friction between the ratchet threads of the pin and slot connection between the tubing and element A of this device is sufiicient to enable the J-slot to be freed without unscrewing the connection.

After the packer has been set in the desired position and connected to the tubing, fluid can flow through the tubing from the space below the packer without leaking out into the annulus between tubing and casing since all the pertinent joints and connections are sealed.

Resilient Friction Connection An important element of the invention is the split nut and threaded mandrel of the resilient friction connection between the inner member and sub A. The basic concept of this means is a spring loaded pair of wedges and instead of the buttress thread type of wedges other wedges could be used. For example the resilient friction means may comprise a tapered mandrel having a correlatively tapered member therearound. The thread form of wedge is preferred however because it facilitates the assembly of a nut and mandrel having a multiplicity of turns of tapered members whereby any desired resistance can be created. Also, without any radical change in design the mandrel and nut can be constructed to have greater or less resistance to relative motion. Increasing the length of the threads increases the resistance; shortening the length of the threads reduces the resistance. Or a portion of the thread on one of the two parts can be machined off to reduce the resistance. Therefore, the device is readily adaptable to put any desired load on the sealing element of the packer or plug being set.

Although perhaps the simplest way of creating the desired frictional resistance to relative motion of nut and mandrel is to use spring loaded wedges whose frictional resistance increases as the wedges move and further strain the spring (the spring being the resilient split nut in the preferred embodiment), the wedges actually function only to cause the friction force to increase with relative motion of the nut and mandrel and if the initial loading of the spring is made high enough the wedges can be dispensed with entirely. For example a shrink fitted sleeve could be substituted for the split nut and the mandrel and sleeve could be unthreaded. This would still be a resilient friction means however because the force creating the friction would still be due to the resilience of the sleeve tending to contract the sleeve to a smaller diameter than the mandrel. The important thing is to provide, either initially by preloading the spring or ultimately by the action of wedges, resistance to relative motion of mandrel and nut or sleeve so that the sealing element of the packer or plug can be properly set. Once the nut has moved far enough relative to the mandrel to set the upper slips any additional weight on the tubing is largely transferred to the casing without imposing much more load on the seal element. It is of course also necessary that the resilient friction means have a resistance to retrograde motion sufiicient to hold the wedge body in place in the upper slips, but this resistance need not be nearly as large as that required to set the seal element. Due to the mechanical advantage of the wedge body the force needed to hold it in place is much less than the force on the slips which it can resist.

While preferred embodiments of the invention have 19 been shown and described many modifications thereof can be made by one skilled in the art without departing from the spirit of the invention and it is desired to protect by Letters Patent all forms of the invention falling within the scope of the following claims.

I claim:

1. A well device comprising:

an elongated inner member having an upper end and a lower end,

a sub at the upper end of said inner member,

means at the upper end of said sub for connecting it to means for lowering the device into a well,

means connecting the sub to the inner member for limited longitudinal relative motion between the sub and inner member,

resilient friction means connecting the sub to the inner member preventing downward longitudinal movement of the sub relative to the inner member except when a predetermined downward force is exerted on the sub and including a member forming a portion of the device and resiliently bearing against a surface on another portion of said device providing frictional resistance to downward motion of the sub relative to the inner member, one of said portions being carried by the sub and the other by said inner member,

first slip type anchor means connecting said sub to the inner member and settable upon the downward longitudinal motion of said sub relative to said inner member and releasable by upward motion of said sub relative to said inner member,

an abutment affixed to said inner member below said slip type anchor means and including a downwardly facing surface,

a second abutment axially slidably mounted on said inner member and including an upwardly facing surface disposed below and spaced from said downwardly facing surface,

a sealing material sleeve coaxial with said inner member disposed about said member between said downwardly facing surface and said upwardly facing surface and expansible upon reduction of the axial distance between said abutments to sealingly engage a surrounding medium,

support means for exerting an axial force mounted on said inner member for axial sliding'movement relative to said inner member and disposed below said second abutment,

a second slip type anchor means below said second abutment and above said support means and connecting said second abutment to said support means and settable upon axial relative motion of said second abutment toward the lowermost part of said support means and releasable upon axial relative motion of said second abutment away from the lowermost part of said support means, eans resisting axial movement of said support means relative to said second abutment to prevent premature setting of said second slip type anchor, and

means through which an upward thrust can be exerted on said support means whereby when a downward thrust is exerted on said sub said second anchor means is set, said sealing material sleeve is expanded, and said first anchor is set.

2. The combination of claim 1 including means for transmitting rotational motion from said sub to said inner member, and in which said resisting means includes a member having a J-slot formed therein and a pin member movable in said slot, one of said members being connected to said support means and the other to said inner member.

3. A well device comprising an elongated inner member having an upper end and a lower end,

a sub at the upper end of said inner member,

means at the upper end of said sub' for connecting it to means for lowering the device into a well,

means connecting the sub to the inner member for limited longitudinal relative motion between the sub and inner member, i

resilient friction means connecting the sub to the inner member preventing downward longitudinal movement of the sub relative to the inner member except when a downward force exceeding a predetermined force is exerted on the sub and including a sleeve carried by the sub resiliently bearing against a surface on the outer portion of a mandrel forming a part of the inner member providing frictional resistance equal to said predetermined force to resist downward motion of the sub relative to the inner member,

first slip type anchor means connecting said sub to the inner member and settable upon downward longitudinal motion of said sub relative to said inner member and releasable by upward motion of said sub relative to said inner member, and including a wedge body,

a plurality of slips disposed around said wedge body, and

means mounting said slips for radial in and out motion while preventing longitudinal motion thereof,

said body and the last said means being connected one to the sub and the other to said inner member,

an abutment afiixed to said inner member below said slip type anchor means and including a downwardly facing surface,

a sealing material sleeve coaxial with said inner member disposed about said member between said downwardly facing surface and said upwardly facing surface and expandable upon reduction of the axial distance between said abutments to sealingly engage a surrounding medium,

support means for exerting an axial force mounted on said inner member for axial sliding movement relative to said inner member and disposed below said second abutment,

a second slip type anchor means below said second abutment and above said support means and connecting said second abutment to said support means and settable upon axial relative motion of said second abutment toward the lowermost part of said support means and releasable upon axial relative motion of said second abutment away from the lowermost part of said support member and including a wedge body, 7

a plurality of slips disposed around said wedge body, and

said body and the last said means being connected one to said second abutment and the other to said support means,

means resisting axial movement of said support means relative to said second abutment to prevent premature setting of said second slip type anchor means,

and 7 means through which an upward thrust can be exerted on said support means whereby when a downward thrust is exerted on said sub said second anchor means is set, said sealing material sleeve is expanded, and said first anchor is set.

4. The combination of claim 3 in which said sleeve is prestressed. I

5. The combination of claim 3 in which said outer portion of the mandrel has a downwardly facing buttress thread therearound and said sleeve is a split nut threaded correlative to said thread on said outer portion of the mandrel.

6. The combination of claim 3 in which said means for connecting the sub to means for lowering the device into a well comprises a threaded socket connected to said sub and a ratchet threaded pin received in said socket and adapted for connection to means for lowering the device into a well. n s

7. The combination of claim 3 in which the thrust means comprises casing engaging friction drag means connected to the support means, and the resisting means comprises a releasable connection between the inner member and support means for preventing relative axial motion therebetween. V

8. The combination of claim 3 in which the inner member is tubular and'the resisting means comprises a draw bar extending axially through said inner member and the support means includes shearable means connected to the lower end of the draw bar, and said thrust means comprises a piston connected to upper end of the draw bar.

9. The combination of claim .3 in which the inner member is tubular and the resisting means comprises a releasable connection between the 'inner member and the support means for preventing relative axial motion therebetween and said resisting means further includes a draw bar, the support means including shearable means connected to the draw'bar;

10. The combination of claim 9 in which the thrust means comprises friction drag means resiliently mounted for radial in and out motion between retracted position and casing engaging position, the resisting means further includes a second shearable means connecting the draw bar and inner member and friction drag means, said second shearable means holding said friction drag means in retracted position. V i i 11. Resilient friction means comprising a threaded mandrel and a split nut in engagement therewith, said nut being of increasing radial thickness progressing away from said split on both sides of the split.

12. A hold down anchor comprising a an elongated inner member having upper end and alower end, v a '7 a sub at the upper end of said inner member, means'at the upper end of said sub for connecting it to means for lowering the anchor into a well, means connecting the sub to the inner member for limited longitudinal relative motion between the sub and inner member," 7 i 4 resilient friction means connecting the sub to the inner member preventing downward longitudinal movement of the sub relative to the inner member except when 'a downward force exceeding a predetermined force is exerted on the sub and including a member forming a portion ofthe anchor and resiliently bearing against a surface on another portionpf said anchor providing frictional resistance equal to said predetermined force to resist downward longitudinal motion of the sub relative to the inner member, one of such portions being carriedlby the sub and the other by the inner member,

slip type anchor means connecting the sub to the inner member and settable upon downward longitudinal motion of said sub relative to said inner member and releasable by upward motion of said sub relative to said inner member,

and means on the lower end of said inner member for connecting it to a device to be set in a well and held down by the anchor.

13. A hold down anchor comprising an elongated inner member having an upper end and a lower end, a sub at the upper end of said inner member, means at the upper end of said sub for connecting it to means for lowering the anchor into a well,

resilient friction means connecting the sub to the inner member and including a member forming a portion of the anchor and resiliently bearing against a surface on another portion of said anchor providing frictional resistance to longitudinal motion of the sub relative to the inner member, one of such portions being carried by the sub and the other by the inner member,

and means on the lower end of said inner member for connecting it to a device to be set in a well and held down by the anchor,

said resilient friction means comprising a downwardly flaring tapered portion on said inner member and a correlative upwardly flaring tapered portion on said sub and means resiliently urging said portions into engagement.

14. The combination of claim 13 in which said means resiliently urging said portions into engagement is a resilient sleeve split vertically and said upwardly flaring tapered portion is provided by the lower flank of a thread formed on the inner periphery of said sleeve and said downwardly flaring tapered portion is provided by the upper flank of a thread formed on the outer periphery of said inner member.

15. The combination of claim 14 in which the normal unstressed inner diameter of said sleeve is less than the correlative outer diameter of said inner member.

16. The combination of claim 15 wherein the sleeve is of progressively increasing wall thickness from the split to the section directly opposite the split.

17. The combination of claim 13 wherein the taper angle of said tapered portions is within the angle of repose for the materials of which said portions are formed.

18. A well device comprising an elongated inner member having an upper end and a lower end, a sub at the upper end of said inner member, means at the upper end of said sub for connecting it to means for lowering the device into a well,

resilient friction means connecting the sub to the inner member and including a sleeve carried by the sub resiliently bearing against a surface which is the outer portion of a mandrel forming part of the inner member and providing frictional resistance to downward motion of the sub relative to the inner member, said outer portion of the mandrel having a downwardly flaring tapered portion and said sleeve having an inner portion tapered correlative to said tapered portion of the mandrel,

first slip type anchor means connecting said sub to the inner member and including slip expander means connected to the sub and slips mounted on the inner member by means providing for radial in and out motion thereof while preventing longitudinal motion thereof, said slips being expanded radially outwardly by the slip expander means upon downward longitudinal motion of said sub relative to said inner member an abutment affixed to said inner member below said slip type anchor means and including a downwardly facing surface,

a second slip type anchor means including a cage surrounding the inner member below said second abutment and above said support means and connecting said second abutment to said support means, expander means on said second abutment and slip mounted in said cage actuatable by said expander means and settable upon axial relative motion of said second abutment toward the lowermost part of said support means and releasable upon axial relative motion of said second abutment away from the lowermost part of said support member,

releasable means connecting said support means to said inner member resisting axial movement of said support means relative to said second abutment to prevent premature setting of said second slip type anchor means, and

19. The combination of claim 18 in which said tapered portion of the mandrel is a thread thereon whose upper flank lies at an acute angle to the axis of the mandrel and flares downwardly and said tapered portion of the sleeve is a thread correlative to said thread on the outer portion of the mandrel.

20. The combination of claim 18 in which said outer portion of the mandrel has a plurality of downwardly flaring tapered portions thereon and said sleeve has a plurality of correlatively tapered portions on the interior thereof and is split.

21. A hold down anchor comprising an elongated inner member having an upper end and a lower end,

a sub at the upper end of said inner member,

means at the upper end of said sub for connecting it to means for lowering the anchor into a well,

resilient friction means connectingthe sub to the inner m mber preventing downward longitudinal movement of the sub relative to the inner member except when a downward force exceeding a predetermined force is exerted on the sub and including a member forming a portion of said anchor having a wedging surface thereon and resiliently bearing against a wedging surface on another portion of said anchor providing frictional resistance to longitudinal motion of the sub relative to the inner member, one of said portions being carried by the sub and the other by the inner member, the wedging surface carried by said inner member flaring downwardly and the wedging surface carried by said sub flaring upwardly,

slip type anchor means connecting the sub to the inner member and settable by downward longitudinal motion of said sub relative to said inner member 15 16 and releasable by upward motion of said sub relameans on the lower end of said inner member for tive to said inner member and-including connecting it to a device to be set in a well and held a wedge body, down by the anchor. Y a g g Slips disposed around Said Wedge References Cited in the file of this patent o y, an means mounting said slips for radial in and out 5 UNITED STATES PATENTS motion while preventing longitudinal mo i 2,404,692 Church July 23, 1946 thereof, 2,681,113 Baker et al June 15, 1954 said body and the last said means being connected 2,778,430 Baker Jan. 22, 1957 one to the sub and the other to said inner mem- 10 2,845,127 Breaux July 29, 1958 her, and 2,887,162 Le Bus May 19, 1959