US2834415A - Tubing packer - Google Patents

Description

G. BOER TUBING PACKER Filed May 17. 1954 May 13, 1958 Flaz INVENTOR. l George Boer BY A ro EY .Mii

United 'States Patent() TUBING PACKER George Boer, Houston, Tex., assignor, by mesne assignments, to Esso Research and Engineering Company, Elizabeth, N. J., a corporation of Delaware Application May 17, 1954, Serial No. 430,207 3 Claims. (Cl. 166-139) The present invention is directed to a packer adapted to be connected into a tubing string. More particularly, the invention is directed to a tubing packer which is easily releasable from engagement with the walls of a casing. In its more specific aspects, the invention is directed to a tubing packer incorporating a novel packing member.

The present invention may be briefly described as a packer adapted to be connected into a tubing string which comprises, in combination, a full opening tubular mandrel. A packer sleeve assembly is embraceably mounted on said packer mandrel and is connected thereto by frangible means which may be released. The packer sleeve is provided with a plurality of pipe slips arranged in a slip cage assembly carried on the rst end of the packer sleeve. The packer sleeve also is provided with a plurality of friction springs carried on the rst end of the packer sleeve adjacent the pipe slips for holding the packer sleeve against rotation with respect to the packer mandrel.

The packer is provided with releasable means which comprises at least one L-slot in the slip cage assembly and at least one lug on the packer sleeve slidable in the L-slot for setting the pipe slips for engaging with a wall of a casing. The packer is provided with a helical, reinforced deformable packer member arranged on and connected to the second end of the packer mandrel and to the lsecond end of the packer sleeve for providing a seal in the annulus between the tubing and the casing on downward movement of the second end of the packing member with respect to the packer sleeve. Downward movement of the packer mandrel compresses the packing member into sealing engagement with the wall of the casing. The second end of the packer mandrel is provided with threaded means engageable with the second end of the packer sleeve for rotational movement of the packer mandrel for compacting the packer mandrel to allow uniform wrapping of the packing member on the packer mandrel.

The packer of the present invention may be set and released while using relatively slight force thus permitting a majority of force available to be applied to dislodge sand, drilling mud and the like material which may resist dislodgment of the packer. Therefore, the present invention has considerable utility in oil producing operations and the like.

The invention will be further illustrated by reference to the drawing in which Fig. l is a partial sectional View of the upper portion of the device of the present invention arranged in a well casing and incorporated into a tubing string;

Fig. l-A is a sectional view of the lower portion of the device shown in Fig. l;

Fig. 2 is a sectional view taken along the lines 2--2 of Fig. l;

Fig. 3 is a sectional view taken along the lines 3-3 of Fig. 1; and

iidligllii Fig. 4 is a view showing the packing member in seal ing engagement with the wall of the casing.

Referring now to the drawing in which identical numerals will be employed to designate identical parts, numeral 11 designates a well casing arranged in a well bore drilled in the earth. A tubing string 12 is run into the well and has made up into it a packer mandrel 13 connected at its upper end to the tubing 12 by packer head 14. Embracing the packing mandrel 13, which is a full opening tubular member providing a passageway 15 therethrough, is a packer sleeve assembly 16 to the upper end of which is connected and forms part of the sleeve assembly 16 is a threaded compacting means 17' which is provided with threadedtype grooves 18. It is to be noted that an intermediate portion of the packer mandrel 13 is provided with projections 19 for engagement with the threaded grooves 13 and for contact with internal shoulder 5t? of means 17.

A slip cage assembly 20 is provided with L-slots 21 in which are arranged lugs 22 carried by the packer sleeve 16. The slip cage assembly 2li `is provided with a plurality of friction springs 23 which are attached to spring sleeves 24 and 2S which are adapted to snap into recesses 26 and 27 of the slip cage assembly 20. The friction springs 23 are adapted to engage with the Wall of casing 11, as shown. The slip cage assembly Ztl is also provided with a plurality of pipe -slips 28 which are adapted to be urged into operative position by steps 29 on the packer sleeve 16. The slips 28 are normally held in inoperative position by band springs 30 and 31 which embrace the slips circumferentially and are arranged in the recesses 32 and 33 of the slips 28.

The packer -sleeve 16 is releasably connected to the packer mandrel 13 by frangible means, such as shear pins 34, adjacent the lower end of the packer mandrel. The shear pins 34 are arranged in a coupling 35 which threadedly connects the lower end of tubing 12 with the packer mandrel 13. Connected to the packer head 14 is ahelical, reinforced deformable packing member 40 which is spiraled on the packer mandrel 13. The deformable packing member 40 is connected also to the compacting means 17, as shown in the drawing.

It is to be noted that the projections 19 are arranged on a collar 41 which is threadedly connected into and forms part of the packer mandrel 13.

The operation of the apparatus of the present invention is as follows:

The device as shown in the drawing is made up into a tubing string, such as 12, and is lowered to the desired setting depth in a well casing, such as 11. The friction springs 23 are in contact with the well casing and prevent rotation of the slip cage assembly 20 to allow further movement downward of the tubing 12 and the other elements of the packer relative to the slip cage assembly 20. This downward movement takes place by rotating the packer sleeve 16 to the left (as shown) to cause the lug 22 to enter the vertical portion of the L-slot as indicated. Downward movement of the tubing 12 causes the steps 29 of the packer sleeve 16 to seat the slips 2S and engage with the wall of the well casing. The slip seating is accomplished with a force limited only by the shear strength of the shear pins 34 which holds the packer sleeve 16 against the packer mandrel 13, as shown. After the slips have been set, tubing weight of a predetermined amount is set down on the tubing 12 to shear the pins 34 which allows continued relative movement of the packer mandrel with respect to the slips28 and the slip cage yassembly 20. The tubing is moved downward; while rotation to tighten the deformable packer member 40 is accomplished either at the wellhead or by allowing the weight of the pipe to cause rotation as the threaded projections 19 traverse the threaded grooves i 1S in the compacting means 17. Movement downward of the tubing 12 and packer mandrel 13 with respect t0 the element 17 causes the deformable packer member 40, which has been tightened rotationally as described, to be compressed vertically and expanded horizontally into sealing engagement with the wall of the casing 11.

The projections 19 and the grooves 18 cause rotation and uniform wrapping of the deformable packing member 40 on the packer mandrel 13 to achieve a compacting seal with the casing 11. This operation is illustrated in Fig. 4.

When it is desired to remove the packer from the casing or well bore a tension or strain is taken on the tubing 12 which lifts the packer head 14 from its compressing position on top of the helical or spiral packing member 40 which, by the same movement, is being unspiraled by rotational movement of the projections 19 upward through the threaded-type grooves 18 of the packer compacting element 17.

It will be thus seen that surface Contact friction is relatively minimized in the present invention since the surface of the packer which forms a seal is effectively altered in the sealing operation.

Further movement upward of the tubing 12 and mandrel 13 allows contact between the threaded projection 19 and the internal shoulder 5t? of the member or compacting means 17. This relative movement unseats the slip steps 29 which are retracted into inoperative position by the band springs 30 and 31. The packer is thus freed from engagement with the wall of casing 11 and the lugs 22 then move upward as far as possible in the slip cage 20 and the device may be rotated to the left or counterclockwise (optional direction). The device is then in position to be pulled from the casing.

The packer member 40 employed in the present invention may suitably be constructed of natural or synthetic rubber or synthetic elastomers well-known to the art. It is desirable to reinforce the packing member 40, such as by internal reinforcing means, such as fiber cords, metallic members and the like.

While the releasing assembly for the slips has been illustrated by an L-slot and a lug, other releasing assemblies, such as J-slots and pins and the like, may be used.

The nature and objects of the present invention having been completely described and illustrated, what I wish to claim as new and useful and to secure by Letters Patent is:

1. A packer adapted to be connected into a tubing string which comprises, in combination, a full opening tubular packer mandrel, a packer sleeve assembly embraceably surrounding the lower end of said packer mandrel, frangible meana` releasably connecting said packer mandrel to said packer sleeve, a slip cage assembly carried on the lower end of said packer sleeve, a plurality of pipe slips arranged in said slip cage assembly, said packer sleeve having stepped surfaces in operative contact with corresponding stepped surfaces of said pipe slips,-a plurality of friction springs carried on said slip cage assembly holding said packer sleeve against rotation with respect to said packer mandrel, releasable means interconnecting said packer sleeve and s-aid slip cage assembly for relative movement for setting said pipe slips by moving the stepped surfaces on the pipe slips and the packer sleeve relative to each other and thereby engaging the pipe slips with the wall of a casing on downward movement of the packer mandrel, a single, continuous, helical, reinforced, deformable solid rubber packing member spirally arranged on and connected by its upper end to said packer mandrel for vertical movement with said packer mandrel and by its lower end to said packer sleeve for rotational movement with respect to its upper end for providing a seal in the annulus between the tubing and a casing on downward movement of the upper end of said packing member with respect to said packer sleeve to compress said packing member into sealing engagement with the wall of said casing, and projection means on the intermediate portion of said packer mandrel threadedly engaging with a groove formed on the inner surface of said packer sleeve for rotational movement of said packer mandrel and providing rotational movement of said packing member on shearing said frangible means by continued downward movement of the packer mandrel whereby uniform wrapping of said packing member on `said packer mandrel is obtained. Y

2. A packer in accordance with claim l in which the releasable means comprises at least one L-slot in said slip cage assembly and at least one lug on said packer sleeve slidable in said L-slot.

3. A packer in accordance with claim l in which the pipe slips -are circumferentially embraced by biasing means for retracting said pipe slips into operative position.

References Cited in the tile of this patent UNITED STATES PATENTS Great Britain 1902

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