US2832419A

US2832419A - Well packers

Info

Publication number: US2832419A
Application number: US432692A
Authority: US
Inventors: Jack C Webber
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-05-27
Filing date: 1954-05-27
Publication date: 1958-04-29
Anticipated expiration: 1975-04-29

Description

April 29, 1958 J. c. WEBBER WELL PACKERS Filed May 2'7, 1954 Jack C. Webe/ INVENTOR.

BY MHZ;

ATTORNEYJ United States atent 2,832,419 WELL PACKERS Jack C. Webber, Houston, Tex. Application May 27, 1954, Serial No. 432,692

Claims. (Cl. 166-138) This invention relates to new and useful improvements in well packers.

An object of this invention is to provide an improved well packer in which the bore of the mandrel extending through the packer is of an increased diameter as compared to previously known packers, whereby increased flow through the bore of the mandrel is obtained when the packer is set in a well casing or pipe.

An important object of this invention is to provide an improved well packer wherein the casing gripping slips and the slip expander are so constructed thatthey can be entirely disengaged to permit full retraction of the gripping slips into contact with a mandrel extending through the packer, whereby the space between the slips and the mandrel which is usually occupied by the expander in prior art packers can be utilized to increase the diameter of the mandrel to thereby obtain a mandrel having an increased internal bore diameter, whereby an increased flow of fluid through the packer can be obtained.

Another object of this invention is to provide an improved well packer in which each of the gripping slips thereof is independntly mounted with a leaf spring, and wherein each of said gripping slips is limited in its inward radial movement by contact with the external surface of the mandrel extending through the packer.

A further object of this invention is to provide an improved well packer having a releasable connector arrangement for connecting the packer housing to the packer mandrel, said connector being automatically engaged upon a longitudinal movement of the mandrel relative to the housing to connect the mandrel to the housing.

The construction designed to carry out the invention will 1 be hereinafter described, together with other features 1 thereof.

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

Figure 1 is a sectional view illustrating the complete well packer of this invention,

Figure 2 is a horizontal sectional view taken on line 2-2 of Figure 1,

Figure 3 is a horizontal sectional view taken on line 3--3 of Figure 1, and

Figure 4 is an elevation of the slotted portion of the special releasable connector means.

In the drawings, the numeral 10 designates the mandrel of the well packer of this invention which has connection with a support or lowering pipe P thereabo-ve, which extends to the surface of the well. The packer housing 12 which surrounds the mandrel 19 carries the friction shoes 14 and the casing gripping slips 15'. A slip expander or cone 17 surrounds the mandrel 10 and fits within the upper end of the housing 12 and is adapted to move longitudinally with respect to the housing 12 for actuating the slips 15 radially into gripping contact with a well casing or pipe (not shown). An annular packing or sealing element Patented Apr. 29, 1958 18 is mounted above the cone 17 and is formed of resilient or elastic material such as rubber, so that it can be radially expanded into sealing contact with the well casing. The packing element 18 is expanded radially by packing expander Zll exposed on the upper end of the mandrel 10, as will be explained. Near the lower end of the mandrel 10 a special releasable connector means C is formed which provides a releasable connection between the mandrel 1t) and the packer housing 12. As Will be explained, the connector C is so constructed that it is connected during the lowering of the packer into a well casing or pipe, and upon its release by a right hand or clockwise rotation, the mandrel 111 can be lowered to expand the annular sealing elementllil and the gripping slips 15 into contact With the casing. Thereafter, the mandrel 16 can be raised relative to the packer housing 12 and the connector C will automatically be engaged to connect the mandrel 10 to the housing 12 for the removal of the packer from the well casing.

Considering the well packer of this invention more in detail, it can be seen inlFigure 1 that each of the gripping slips 15 is mounted on a leaf spring 22 which is secured at its lower end to the internal surface of the housing 12 by a bolt and nut connection 23 or other equivalent securing means, and the upper end of each spring 22 is secured to each of the slips 15 by a rivet 24 or similar secur ing means. The spring 22 upon which each of the gripping slips is mounted tends to move the gripping slips radially inwardly to a retracted position with the rear or inner longitudinal surface 15a of each of the slips 15 contacting the external surface of the mandrel 10 (Figure 1). Each of the slips is adapted to be moved radially outwardly through openings 26 in the housing 12, and such outward movement is limited by the flanges or cars 27 at each side of each of the slips 15 (Figure 2).

The expander cone 17 which is disposed above the gripping slips is adapted to move longitudinally with respect to the slips 15 and the slip housing 12 within limits. The upper limit of movement of the cone 17 is determined by the radial ring 3-51 threaded into the inner surface of the housing 12 at its upper end, whereby the annular shoulder 17a is adapted to contact the lower annular surface or shoulder of the ring fit). The cone .1? is held in its upper position out of contact with the slips 15' by an annular flange 112a. By reason of such construction, the diameter of the mandrel can be increased to provide an increased bore through the mandrel. The lower limit of travel of the cone is determined by the contact of the external conical or tapered surface 17b with the internal tapered surfaces 15b of the slips 15. The external surface 171) of the cone 1"] has substantially the same taper as the internal surfaces 15b of the slips 15 so that as the cone 17 moves downwardly with respect to the slips 15, a wedging action results which moves the slips 15 radially outwardly intogripping contact with the well casting (not shown).

The cone 17 has an annular tubular extension 31 which surrounds the mandrel 1i and which projects above the ring 361 and to which is attached the packing element 18. This attachment is preferably provided by a threaded collar 32 which is made integral with the packing element 13 by a metallic insert 33 which is molded into the packing element 13 and is welded or otherwise secured to the collar 32. The lower end of the packing elementlll has an annular ll-shaped anti-extrusion ring 35.

To effect the radial expansion of the packing element 13 and the gripping slips 15 into contact with the well casing, the mandrel ill is provided at its upper end with a packing element expander cone Ztl which has a downwardly and inwardly tapered external conical surface 20a which is adapted to fit within the bore 13;: of the pack ing element 18. Also, below such packing element expacker.

pending cone an annular radial shoulder or flange 36 is provided around the mandrel for contact with an inwardly extending radial surface or stop 31a in the tubular sleeve 31; in the event the packing element is extruded beyond intended limits, the surface 36 will contact the surface 31a to relieve the packing element 18 of further tubing load. Also, it will be observed that although the lip 31b has an internal diameter just slightly larger than the external diameter of the lower cylindrical section 20b in order to prevent extrusion of the rubber of the packing element therebetween, the sleeve 31 has an enlarged diameter recess 310 with an equalizing port 31d for preventing any of such rubber which is extruded below the lip 31b from exerting a frictional resistance over an extended longitudinal area of the mandrel.

The housing 12 carries the friction shoes 14 which are adapted to contact the well casing at all times to resist rotation and longitudinal movement of the housing 12. Each of the shoes 14 is urged radially outwardly by a plurality of longitudinally spaced coil springs which are positioned inwardly of the shoes 14 and are fitted within recesses 14:: of the shoes and similar recesses 41a in a back-up plate 41 which is secured to the inside of the housing 12. The extent of outward movement of the shoes 14 is limited by flanges or ears 14b on the sides of each of the shoes 14.

The special connector means C includes a slotted body secured to the external surface of the mandrel 10 near its lower end by welding 49 or any other suitable securing means, whereby said body 51) moves with the mandrel 10. A plurality of slots 51 are formed on the body 50 for receiving a corresponding number of pins 52 which are carried by a housing extension 12a at the lower end of the housing 12 and which extend radially inwardly to fit within the slots 51. Preferably there are three slots 51 and three of the pins 52, although the number may, of course, vary. Each of the slots 51 includes an inclined guide wall 51a which leads to a bottom wall 511; and which is joined to a longitudinally extending guide wall 510. At the upper end of the guide wall 510 a depending hook 51d is formed to provide a confining hook recess 512 in the slot 51. The upper end 51] of each of the slots 51 is open and the hook 51d is formed on its upper end at 51k so that each pin 52, upon contact with the upper hook surface 51k during an upward movement of the body 50 relative to the pins 52, will be guided into the open portion 51f and subsequently will be guided along the inclined wall 51a toward the bottom wall 5112, as will be explained. The

pins 52 fit within the hook recesses 51:2 when the packer is being lowered in the well bore so that the mandrel carries the packer and is prevented from being separated therefrom.

Within the housing extension 1241, a guide ring 55 is positioned and is held against downward movement by set screws or retaining screws 56 and against upward movement by the lower ends or surfaces of the back-up plates 41 of the friction shoes 14. The guide plate 55 serves to guide or maintain the mandrel 1b in axial alignment relative to the packer housing 12 after the pins 52 have been disconnected from the slots 51.

In the operation of the well packer of this invention, the packer is lowered on the support or lowering pipe P (a portion of which is shown in Figure l) which has connection with the mandrel 10 extending through the During such lowering movement, the pins 52 are in the hook recess portions Sle of the slots 51 so that the mandrel 10 is positioned slightly downwardly with respect to the housing 12 from that shown in Figure l. It should be noted that the annular support flange ltla on the mandrel 10 which ordinarily retains the slip cone 17 spaced above the slips 15 would be moved with the mandrel downwardly from its position shown in Figure 1, but it is sufficiently spaced above the inner longitudinal surfaces 15a of the slips 15 so that it does not 4: contact same and so that the cone surface 17b does not contact the inner tapered surfaces 15b of the slips 15 during the lowering movement of the packer into the casing.

The friction shoes 14 tend to drag the housing 12 during the lowering operation so that the pins 52 remain in the recesses 51c and therefore, the mandrel 10 and the housing 12 remain connected during the lowering operation. When the packer has been lowered to a predetermined point in the well casing, the support pipe P is rotated to rotate the mandrel 10 in a right-hand direction or clockwise (as viewed from above in Figure 1). The friction shoes 14 prevent a rotation of the housing 12 during the rotation of the mandrel 10 so that the pins 52 are guided from the hook recess 51a along the hook 51d to the open end 511 of the slot 51. Thereafter, upon lowering the mandrel 10, due to the friction shoes 14 retaining the packer housing 12 against longitudinal movement,

the pins 52 will move through the open ends 51] of the.

slots 51 so that the mandrel 10 is then free to move downwardly with respect to the housing 12. This permits downward movementof the expander 20 into the bore 18a of the packing sleeve 18 to transmit a downward movement of the sleeve 18 to the cone 17 relative to the housing 12 to force the cone expanding surface 17b into contact with the surfaces 15b of the slips 15, and upon continued downward movement the slips 15 are wedged radially outwardly by the cone 17 into gripping contact with the well casing. Substantially simultaneously with the radial expansion of the slips 15, the packing element expander 20 expands the packing element 18 radially to move it into sealing engagement with the casing.

After the usual well operations have been carried out with the packer in the set position in the casing, the packer may be retracted and removed from the casing, or moved to a different position within the casing, by lifting the support pipe P and the mandrel 10 relative to the packer housing 12. Upon such raising of the mandrel 10, the curved upper hook surfaces 51k of the slotted body member 50 will contact the pins 52 and will effect a turning of the body member 50 so as to direct such pins 52 into the open ends of areas 51 of the slots 51, whereupon the body member 50 will be guided in a left hand or counter clockwise direction (as viewed from the top of Figure 4) by the contactof the inclined walls 51a of the slots 51 with the pins 52. It will be apparent that in some cases the pins 52 will already be aligned with the open ends 51 so that contact with the hook surfaces will not occur, but the guiding of the body member 50in a left-hand direction by the contact of the pins 52 with a portion of the guide walls 51a will still result. Also, the pins 52 may be initially contacted by the upper surfaces of the hooks 51d, in which event the body member 50 is guided in a right hand or clockwise direction (as viewed from the top of Figure 4) until the pins 52 reach the area below the hooks 51d, at which time the twist in the pipe P from the turning movement of the body member 50 causes the body member 51 to turn to the left to position the pins 52 below the hooks 51d. The body member 50 is thus guided relative to the pins 52 to position same at the lower wall or surface 51b of the slots 51 below the hook recesses 512 and because of the construction of the slots 51, as above explained, the relative movement between the pins 52 and the body member 50 positions the pins 52 in the slots 51 upon a longitudinal movement of the mandrel 10 upwardly relative to the housing 12 without requiring rotation of the mandrel 10.

During the engagement of the pins 52 and the slots 51, as above explained, the annular shoulder 10a on the mandrel 10 is moved upwardly and carries upwardly the cone 17 with respect to the slips 15 so as to move the slip cone 17 to its upper limit of travel with the upper end 17a thereof in contact with the annular lower surwould be necessary if the cone 17 were maintained inside of the slips 15, as in the conventional construction. Thus, it is apparent that with this construction of this invention, an increased size of mandrel and therefore an increase diameter of the bore or passage through the mandrel It) can be obtained, as compared to prior known constructions, while still permitting full retraction of the slips 15 from engagement with the well casing.

The packer, of course, assumes the position shown in Figure 1 during the removal of the packer from the easing, and if it is desired to again set the packer at some point in the casing, the support pipe and mandrel can again be lowered and the above sequence of operations for setting the packer can again be carried out.

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

Having described the invention, I claim:

1. A well packer adapted to be lowered into a well casing, comprising a packer housing having attached thereto casing gripping slips adapted to be radially movable in and out of slots in said housing, resilient means supporting said slips and urging same radially inwardly to a retracted position out of contact with the well casing, a mandrel extending through the packer housing, a connector means including a slotted body disposed adjacent the lower end of the packer housing and secured to said mandrel, means on said housing extending into said slotted body when said mandrel and said housing are in connected position, said connector means being adapted to be connected during the lowering and raising of the packer into the casing but upon rotation of said mandrel and the connector means secured thereto being releasable during the setting of the slips into contact with the well casing, friction means on said housing for holding the same in position in the well casing during release of the connector means and expansion of the casing gripping slips, an expander member surrounding said mandrel and disposed above said slips and spaced therefrom when the slips are in a retracted position, a flange on said mandrel for contact with the expander member to hold same in retracted position out of contact with the slips, said expander member having a reduced portion extending above said packer housing, an outwardly extending shoulder on said expander member below said reduced portion and within said housing, an inwardly extending shoulder on the upper end of said housing adapted to be engaged by said shoulder on the expander member to effect a lifting of said housing upon the raising of said mandrel with said flange in engagement with said expander member, a packing element supported on the reduced portion of the expander member, means on the mandrel for moving said expander member downwardly with respect to the slips for engaging the slips to radially move the slips into engagement with the casing, and additional means on the mandrel adapted to radially expand the packing element upon the downward movement of the mandrel, whereby the packing element and the 6 slips are both set in contact with the casing upon the downward movement of the mandrel with respect to the packer housing.

The structure set forth in claim 1, wherein said packing element is an annular resilient member having an 9 en bore through which the mandrel extends, the wall of said here being substantially parallel to the external surface of said mandrel, and wherein the additional means for expanding said packing element includes a cone ad Jted to enter the bore of said packing element t t he radial expansion of said element into contact till the well casing.

3. The structure set forth in claim 1 wherein said means on said housing includes a pin. on the housing adapted to extend radially inwardly into the slot of the slotted body when said mandrel and said housing are connected, said slot being formed with an open upper end and a guide wall extending downwardly therefrom and inclined in a clockwise or right-hand direction, said slot also including a hook disposed adjacent the open upperend and adapted to receive the pin to prevent upward movement of the pin relative to the slotted body, the inclined guide wall positioning the pin below said hook so that upon an upward movement of the slot relative to the pin said pin seats in the recess of the hook, said pin being removable from said hook upon a righ hand rotation of the mandrel, whereby the pin is moved into the open upper end of the slot to effect the release of the connecting means and thereby to effect the release of the mandrel from the housing.

4. The structure set forth in claim 1, wherein said resilient means supporting the gripping slips includes a leaf spring connected to each of the slips individually and to the housing for resiliently urging the slips radially inwardly to a retracted position in contact with the mandrel, and wherein each of said slips has retaining ears at the sides thereof for engagement with the inner surface of the housing to limit the extent of outward movement of the slips relative to the housing.

5. The structure set forth in claim 1 wherein said means on said housing includes a pin on the housing adapted to extend radially inwardly into the slot of the slotted body, said slot having a hook portion for confining the pin against upward movement relative to the slotted body and the mandrel, whereby the housing is confined against upward movement relative to the mandrel, said hook portion having a curved guide surface thereabove which is adapted to guide the pin into an open end of the slot upon an upward movement of the slotted body relative to the pin, and an inclined guide wall in the slot for guiding the pin to a position directly below said hook portion for subsequent seating in the hook portion upon a downward movement of said body relative to said pin, said pin being removable from the hook portion into the open portion of the slot upon a rotation of the mandrel relative to the housing and upon subsequent downward movement of the mandrel relative to the housing, whereby the pin and slot are completely disengaged for permitting relative longitudinal movement of the mandrel with respect to the housing.

References Cited in the file of this patent UNITED STATES PATENTS 2,247,188 Davis June 24, 1941 2,404,692 Church July 23, 1946 2,506,795 Koeln May 9, 1950 2,632,514 Fitzpatrick Mar. 24, 1953 2,633,918 Le Rouax Apr. 7, 1953 2,639,773 Webber May 26, 1953