US3283821A

US3283821A - Screw-set packer

Info

Publication number: US3283821A
Application number: US328282A
Authority: US
Inventors: Cicero C Brown
Original assignee: Individual
Current assignee: Hughes Tool Co
Priority date: 1963-12-05
Filing date: 1963-12-05
Publication date: 1966-11-08
Anticipated expiration: 1983-11-08

Description

Nov. 8, 1966 c. c. BROWN 3,283,821

SCREW-SET PAGKER Filed Dec. 5, 1963 2 Sheets-Sheet 1 CICERO c BEOWN TOR. 7/ INVEN Nov. 8, 1966 c. 0. BROWN SCREW-SET PACKER 2 Sheets-Sheet 2 Filed Dec. 5, 1963 C/CEFO C. BROWN I N V EN TOR By uyeaz i A TTO A/EYS United States Patent 3,283,821 SCREW-SET PACKER Cicero C. Brown, 8490 Katy Road, Houston, Tex. Filed Dec. 5, 1963, Ser. No. 328,282 Claims. (Cl. 166-134) The present invention is directed to a well packer assembly in which an inner-mandrel is locked within a cam actuated anchoring device and an outer sleeve which is threaded to the inner mandrel is rotated therearound to set a flexible packing and anchoring assembly positioned between the lower end of the inner tubular support and the lower end of the sleeve. Thus the present invention is directed to a screw set well packer assembly.

An object of the present invention is to provide an improved well packer assembly of simple and inexpensive structure which may be employed as a screw set packer by the rotation of one member around another member in threaded engagement therewith to compress the flexible packing and anchoring assembly.

Another object of the invention is to provide an improved well packer assembly including a flexible packing and anchoring assembly having upper and lower seal end rings, a resilient expander wedge and upper'and lower slip members positioned between the respective seal end rings and the expander wedge whereby movement of one of said seal end rings toward the other compresses the resilient expander wedge and engages the slip members with the well casing to set the well packer assembly.

A further object of the present invention is to provide a screw set well packer assembly having greatly reduced friction when being run through the well bore than previous devices.

Another object of the present invention is to provide a flexible packing and anchoring assembly in a well packer assembly and including cup-shaped seal collars which will retain differential pressures from above and below when such well packer assembly has been set.

A further object of the present invention is to provide a well packer assembly which when set in a well bore is readily released and retrieved from the well bore.

Still another object of the present invention is to provide a well packer assembly which may be lowered within a well bore on a tubing string and set Within the bore and the tubing string removed therefrom subsequent to the setting of the well packer assembly,

These and other objects of the present invention are hereinafter more fully described and explained.

The invention will be more readily understood from reading of the following specification and by reference to the accompanying drawings froming a part thereof wherein an example of the invention is shown and wherein:

FIGURE 1 is a View, partly in section and partly in elevation, of a well packer assembly constructed in accordance with the invention and showing the assembly in a normal or unset position.

FIGURE 2 is a similar view with the assembly in its set position within a well bore.

FIGURE 3 is a similar view with the well packer in its set position within the well bore and with the J-body and tubing string removed therefrom.

FIGURE 4 is a horizontal cross-sectional view taken along lines 4--4 in FIGURE 1.

FIGURE S is a horizontal cross-sectional view taken along line 5-5 in FIGURE 2.

FIGURE 6 is a horizontal cross-sectional View taken along line 66 in FIGURE 2.

In the drawings (FIGURES 1 and 2) the Well packer assembly of the present invention is run into a well bore within the well casing C suspended from the well tubing string T. The well packer assembly includes tubular support 10 which has lower external abutment 11 secured to "ice its lower end in supporting relation to the lower end of the gripping unit A and tubular support 10 is threadedly engaged to the interior of sleeve 12 at its upper end, with flexible packing and anchoring assembly P being positioned around tubular support 10 between slip ring 12a which abuts the lower end of sleeve 12 and the upper end of gripping unit A.

J-body 13 is externally threaded onto tubing T and engages pins 14 within J-slots 15 which are formed in J- body 13. Pins 14 as best shown in FIGURE 6 are integral with sleeve 12.

Section T1 of tubing string T extends through tubular support 10 and is threaded at its upper end into J-body 13 and is provided with a suitable seal 16 around its exterior to seal against the interior of tubular support 10.

Flexible packing and anchoring assembly P includes upper and lower

seal end rings

17 and 18, upper and

lower slip members

19 and 20 mounted integrally with

resilient seal collars

21 and 22, respectively. Preferably, slip

members

19 and 20 are bonded to seal

collars

21 and 22, respectively. With flexible packing and anchoring assembly P in its unset position as shown in FIGURE 1 the

inner surfaces

21a and 22a of

seal members

21 and 22 engage the inclined surfaces 23a and 23b of expander wedge 23 on only a small portion of their length. Upper seal end ring 17 is secured to tubular support 10 by shear pin 17b and has its lower surface 17a in engagement with the upper portion of upper slip member 19 and upper seal collar 21. Surface 17a of ring 17 as shown inclines upwardly and outwardly and mates with similarly inclined surfaces 19a on upper slip member 19 and 21b on upper seal collar 21. Lower seal end ring 18 has downwardly and outwardly inclined surface 18a in engagement with similarly inclined surfaces 20a on lower slip member and surface 2211 on lower seal collar. Lower seal end ring 18 is suitably grooved on its interior surface and is supported on snap ring 24 which is positioned in groove 25 in tubular support 10.

The gripping unit A surrounds the lower portion of tubular support :10. External abutment 1.1 is mounted thereon by snap ring 11a in groove 11b in the lower portion of tubular support 10. External abutment 111 is spaced from seal end ring 18 to provide for the mounting of grip-ping elements S of said gripping unit A around tubular support 10.

As shown in FIGURES 4 and 5, each gripping element S is in the form of a generally semicircular or arcua-te shoe which substantially encircles one-half of tubular support 10. The lower end of each shoe has a depending extension 26 (FIGURE 1) which coacts with an upstanding projection 27 on lower abutment 11 while the upper end of each shoe has an upward extension 28 coaeting with a depending projection 29 for-med on lower seal end ring 18. The coaction between the extensions and projections limits the outward movement of each shoe with respect to tubular support 10.

Each arcuate shoe has an enlarged contact section 30 and the central outer surface 36a of this section is substantially smooth to engage the Wall of the well casing C when the shoe is in non-gripping position. Gripping teeth 3% and 30c are formed on each side of the smooth surface Stla as is clearly shown in FIGURES 4 and 5. The shoes S are positioned amound tubular support 10 within the space between lower abutment 111 and lower sea'l end ring 18 and are urged outwardly under the influence of coil springs 31 so that their respective smooth surfaces 30a engage the Wall of the well casing. The ends of the springs 31 are confined within suitable recesses 32 provided in the free ends of the shoes S and said springs 31 are relatively weak, being only suflicient to urge the smooth areas of the shoes into contact with the wall 3 of the pipe with a relatively light friction. This frictional force need be only sufficient to prevent the .shoe elements from rotating, whereby the assembly may be lowered downwardly through the well casing without presenting any great resistance to such movement.

For the purpose of increasing the engagement of each shoe S with the wall of the casing in order to assure that the tubular support and seal end ring 18 will be held against movement when the assembly is to be set, each gripping shoe S has the internal surface of its enlarged portion 31) inclined in :the manner indicated at 33 and 34. These inclined surfaces are adapted to coact with a cam type projection 35 which is formed on the external surface of tubular support 111. As clearly shown in FIG- URE 4, two diametrically opposed projections 35 are provided and these projections are normally located as shown in this figure with respect to

inclined surfaces

33 and 34 of the arcuate shoes.

Upon rotation of the tubular support 10 and its projections 35 with respect to the shoes S, the projections 35, coacting with one or the

other surfaces

33 or 34 of each shoe, will result in imparting a rocking motion to the shoes :in the manner illustrated in FIGURE 5. Such movement of the shoes results in the engagement of gripping teeth 3% or 30c of each shoe against the wall of the casing to firmly lock the gripping unit A against rotation or other movement within the well casing. Since gripping unit A is carried on tubular support 10 and supports lower seal end ring 18 the setting of gripping unit A will allow packing and anchoring assembly P to be set as hereinafter more fully explained.

In operation the well packer of the present invention will be run into the well bore and when it reaches the desired level within casing C, it will be substantially as shown in FIGURE 1. Setting of the packer is accomplished by rotating the tubing T to the right where-by J- slot .15 engages pin 14 causing sleeve 12 to rotate. Rotation of sleeve 12 will initially cause rotation of tubular support 10 until projection 35 on tubular support 10 has engaged inclined surfaces 34 of the shoes S and thereby set the shoes. Further rotation of the tubing T will cause sleeve 12 to rotate about tubular support 11 and because of the threaded engagement therewith will move sleeve :12 downwardly with respect to tubular support 111. This downward :movement will cause shear pin 17b to shear between the inner surface of upper seal end ring 17 and the outer surface of tubular support 10. Further rotation of tubing T will move sleeve 12 downwardly around tubular support 10 forcing upper seal end ring 17 downwardly and causing upper slip member 19 and upper seal collar 21 to move downward-1y over expander sleeve 23. As upper seal end ring 17 is moved down toward lower seal end ring 18, the

inclined surfaces

17a and 18a of

rings

17 and 18 will force slip member 19 and 2t) and

seal collars

21 and 22 outwardly. Further movement will also cause expander sleeve 23 to move downwardly under lower seal collar 22 and lower slip 20. As sleeve 12 moves further down on tubular support 1t), inclined surface 22a of seal collar 22 will move outwardly on inclined surface 23b of expander sleeve 23 and inclined surface 21a of upper seal collar 21 will move outwardly on the inclined surface 23a of expander sleeve 23 until upper and lower slips 19 and are in firm engagement with the interior wall of casing C and upper and

lower seal collars

21 and 22 are sealed against the interior of casing C between upper and

lower slips

19 and 20 as is clearly shown in FIGURE 2. In this position flexible packing and anchoring assembly P has been set. If desired 'l-body 13 may be removed from around sleeve 12 and J-body 13 and tubing string T completely removed from the well bore as shown in FIGURE 3. In this position the well packer assembly is firmly secured in position against the interior of casing C both by packing and anchoring assembly P and by gripping unit A,

In order to remove the well packer assembly from the well bore it is necessary to engage J-body 13 over sleeve 12 wherein pin 14 is positioned within J-slot 15 as shown in FIGURE 2.. In this position with a slight lift on tubing T pin 14 will be positioned in the lower closed portion of l-slot 15 and may be rotated to the left whereby sleeve 12 will be rotated to the left. This rotation may initially unset projection 35 from inclined surfaces 34 of gripping unit A if the friction in the threads between tubular support 10 and sleeve 12 exceeds the friction between projections 35 and surfaces 34-. Continued rotation will rotate tubular support 10 and projection 35 will then catch the opposite inclined surfaces 33 causing engagement of the teeth 30b in the wall of casing C, thus resetting gripping unit A. Further rotation of the tubing will cause sleeve 12 to rotate about tubular support 10 and move upwardly the threaded connection therebetween. The upward movement of sleeve 12 will allow

seal collars

21 and 22 and expander sleeve 23 to retract and to return to their normal shape. As sleeve 12 continues its upward rotation the resiliency of

seal collars

21 and 22 and expander sleeve 23 will cause

slips

19 and 22 to disengage from the interior casing C and return to their retracted position as shown in FIG- URE 1. With packing and anchoring assembly P thus unseated, it is only necessary to rotate tubing T slightly to the right to disengage projection 35 from inclined surface 33 thereby releasing gripping unit A and the well packer assembly may be pulled from the well bore. Pin 36 extends through sleeve 12 as shown and projects into the space around tubular support 11 below the threads on the upper exterior of tubular support 10. Pin 36 will thus provide a stop for the upward movement of sleeve 12 to prevent sleeve 12 from completely disengaging from tubular support 10.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and the various changes in size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1. A releasable well packer assembly adapted to be lowered on a tubing string and set in a well bore, comprising a tubular support having an external abutment near its lower end,

a sleeve surrounding and threadedly engaging the upper end of said tubular support so that relative rotation between said sleeve and said tubular support moves said sleeve longitudinally on said tubular support,

means mounted on said tubular support and engaging the wall of the well bore to restrain said tubular support against rotation,

a sealing and anchoring assembly mounted around said tubular support between said abutment and said sleeve,

said assembly including a resilient expander wedge having upper and lower conical surfaces which diverge outward toward each other, resilient sealing means associated with said wedge so that both said wedge and said sealing means are simultaneously deformed radially outward in engagement with the Wall of the well bore upon the application of an endwise force thereto and on release of said force to return to their undeformed position, and upper and lower slip members associated with said sealing means and movable outward therewith into pipegripping position with the wall of the well bore when said sealing means is deformed outward,

said restraining means holding said tubular support stationary so that said sleeve may be rotated relative to said tubular support,

such relative rotation in one direction moving said sleeve downward on said tubular support to apply an endwise force against said sealing and anchoring assembly to set the same, and such relative rotation in the opposite direction moving said sleeve upward on said tubular support to remove the endwise force against said sealing and anchoring assembly to release the same. 2. A releasable well packer according to claim 1, including 1111621118 releasably securing said sealing and anchoring assembly to said tubular support and engageable by the sleeve when said sleeve is moved downward on the support, whereby said means is released. 3. A releasable well packer assembly according to claim 1, including means on said sleeve for connection with said tubing string whereby the well packer may be lowered into a well bore and actuated by manipulation of said tubing string at the surface of the well bore. 4. A releasable well packer according to claim 3, wherein said tubing string extends downwardly through said well packer assembly within said tubular support, and sealing means between the exterior of said tubing string and the interior of said tubular support completing the sealing between the exterior of the tubing string and the wall of the well bore when said well packer assembly is set. 5. A releasable well packer assembly according to claim 1, wherein said restraining means includes at least two gripping members mounted on said tubular support and having outwardly projecting gripping surfaces,

means normally holding said gripping surfaces out of gripping engagement with the wall of the well bore, and

means on said tubular support moving said gripping surfaces into gripping engagement with the wall of the well bore responsive to a partial rotation of the tubular support to restrain said tubular support against further rotation and releasing said gripping surfaces from engagement with the wall of the well bore responsive to a rotation of said tubular support in the opposite direction from the direction of rotation moving said gripping surfaces into gripping engagement.

References Cited by the Examiner UNITED STATES PATENTS 1,303,091 4/1919 Mack 166-139 3,066,738 12/1962 Myers 166134 3,096,824 7/1963 Brown 166-138 3,181,614 5/1965 Brown 166134 CHARLES E. OCONNELL, Primary Examiner.

JACOB L. NACKENOFF, Examiner.

J. A. LEPPINK, Assistant Examiner.

Claims

1. A RELEASABLE WELL PACKER ASSEMBLY ADAPTED TO BE LOWERED ON A TUBING STRING AND SET IN A WELL BORE, COMPRISING A TUBULAR SUPPORT HAVING AN EXTERNAL ABUTMENT NEAR ITS LOWER END, A SLEEVE SURROUNDING AND THREADEDLY ENGAGING THE UPPER END OF SAID TUBULAR SUPPORT SO THAT RELATIVE ROTATION BETWEEN SAID SLEEVE AND SAID TUBULAR SUPPORT MOVES SAID SLEEVE LONGITUDINALLY ON SAID TUBULAR SUPPORT, MEANS MOUNTED ON SAID TUBULAR SUPPORT AND ENGAGING THE WALL OF THE WELL BORE TO RESTRAIN SAID TUBULAR SUPPORT AGAINST ROTATION, A SEALING AND ANCHORING ASSEMBLY MOUNTED AROUND SAID TUBULAR SUPPORT BETWEEN SAID ABUTMENT AND SAID SLEEVE, SAID ASSEMBLY INCLUDING A RESILIENT EXPANDER WEDGE HAVING UPPER AND LOWER CONICAL SURFACES WHICH DIVERGE OUTWARD TOWARD EACH OTHER, RESILIENT SEALING MEANS ASSOCIATED WITH SAID WEDGE SO THAT BOTH SAID WEDGE AND SAID SEALING MEANS ARE SIMULTANEOUSLY DEFORMED RADIALLY OUTWARD IN ENGAGEMENT WITH THE WALL OF THE WELL BORE UPON THE APPLICATION OF AN ENDWISE FORCE THERETO AND ON RELEASE OF SAID FORCE TO RETURN TO THEIR UNDERFROMED POSITION, AND UPPER AND LOWER SLIP MEMBERS ASSOCIATED WITH SAID SEALING MEANS AND MOVABLE OUTWARD THEREWITH INTO PIPEGRIPPING POSITION WITH THE WALL OF THE WELL BORE WHEN SAID SEALING MEANS IN DEFORMED OUTWARD, SAID RESTRAINING MEANS HOLDING SAID TUBULAR SUPPORT STATIONARY SO THAT SAID SLEEVE MAY BE ROTATED RELATIVE TO SAID TUBULAR SUPPORT, SUCH RELATIVE ROTATION IN ONE DIRECTION MOVING SAID SLEEVE DOWNWARD ON SAID TUBULAR SUPPORT TO APPLY AN ENDWISE FORCE AGAINST SAID SEALING AND ANCHORING ASSEMBLY TO SET THE SAME, AND SUCH RELATIVE ROTATION IN THE OPPOSITE DIRECTION MOVING SAID SLEEVE UPWARD ON SAID TUBULAR SUPPORT TO REMOVE THE ENDWISE FORCE AGAINST SAID SEALING AND ANCHORING ASSEMBLY TO RELEASE THE SAME.