US2805723A

US2805723A - Well packer

Info

Publication number: US2805723A
Application number: US427289A
Authority: US
Inventors: Young Bob
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-05-03
Filing date: 1954-05-03
Publication date: 1957-09-10
Anticipated expiration: 1974-09-10

Description

B. YOUNG WELL PACKER Sept. 10, 1957 3 Sheets-Sheet 1 Filed May 3, 1954 fiob V0 0/? g INVENTOR.

QHJLL Sept. 10, 1957 B. YOUNG 2,805,723

WELL PACKER Filed May 3, 1954 5 Sheets-Sheet 2 A? 5 06 V0 ung INVENTOR.

Y ew

. 3 A TTO/q/VE Y Sept. 10, 1957 B. YOUNG WELL PACKER Filed May 3, 1954 3 Sheets-Sheet 5 ATTOR/Viy WELL PACKER Bob Young, Scott, La.

Application May 3, 1954, Serial No. 427,289

12 Claims. (Cl. 166-138) This invention relates to oil well tools, and more particularly to an improved packer assembly for sealing off a well at any desired depth and which after being set will effectively withstand applied forces which have caused failures of conventional packers heretofore in use. Conventional packers are apt to become loose at critical times under sharp jars or changes in forces imposed thereon and which shake the tubing string or the casing, or both, whether in or out of phase. Shaking from violent well vibrations may cause gradual slip displacement and eventual packer breakdown and leakage.

It is an object of the present invention to provide an assembly which not only will stand up under and resist vibrations or other forces but instead will tend to become more firmly set by such forces. I

A further object of the invention is to provide a packer assembly which will maintain the pipe string centered as it travel-s in a well to or from the location to be packed and which can be set at selected locations by a simple manipulation of the string from the surface by first releasing a slip abutment from draft connection with the string and then imparting to the string a small downward movement. Thereafter upward force alone on the string will not release the packer, but will act to resist release unless a slight upward pull is applied concurrently with a torque force for rotating the string and backing it upwardly relative to the previously set parts until the original unset relation is gradually restored. Re-establishment of unset relation enables the entire assembly to be moved either completely out of the well or to a new position to be packed off.

Another object of the invention is to provide a packer assembly having an expansible slip shoe for clutching engagement with the wall of the well and a contractible slip shoe for clutching engagement with the tubing string, with the expansible shoe operatively related to a pair of axially spaced expander retainers responsive one to downward tubing string movement and the other to upward tubing string movement, and one of the retainers having movement transmitted to it from the tubing string through the contractible slip connection, which is constituted by a one way clutchingdevice preferably having wickets to grip a co-operating surface on the tubing string in a manner to enable rotational unthreading therefrom when both slips are to be released.

Other objects and advantages will become apparent during the course of the following specification having reference to the accompanying drawings wherein Figure 1 is a vertical sectional view of the packerassembly in unset relation for travel in a well bore; Fig. 2 is a verti cal sectional view of the parts shown in Fig. 1 but with the parts set-in packed off relation; Fig. 3 and 4 are transverse horizontal sectional views taken on lines 3-3 and 44, respectively, of Fig. 1; Figs, 5 and 6 are fragmeutary sectional views showing wedge retainers for the primary slip in contracted and expanded positions, respectively; Fig. 7 is a section of a casing with an expanded packer assembly shown in elevation; and Fig. 8

nited States Patent g 2,805,723 Patented Sept. 10, 1957 is a fragmentary vertical sectional view of the one way contraotible slip.

In a preferred but not necessarily the only embodiment of theinvention as shown in the drawings, the packer assembly comprises a number of parts sleeved on or carried by a pipe string or central mandrel 1 forming a rigid part of the pipe string to be lowered or lifted in a well bore or well casing 2 and to be used for sealing oif the annular space between the walls of the mandrel and well bore. The lowermost sleeve 3 of the assembly is a cast iron cylinder slidably fitted to the mandrel. It has a releasable draft connection with the mandrel, such as a bayonet type latch aflorded by a lateral pin or lug 4 projecting outwardly on the mandrel 1 and a pin receiving J-slot 5 in the lower edge of the sleeve 3. Mounted in the wall of the sleeve 3 behind upper and lower overhanging retainer lips 6-6 and projected outwardly beyond the sleeve periphery is a group of yieldable block 7 of molded rubber or other elastic deformable material, each having a wear resistant slide bearing surface conveniently aiforded by metal strips 8 whose opposite terminals are bent inwardly and preferably barbed and embedded within the rubber body. Four or more equally spaced blocks 7 arranged to fit snugly for fric tional drag on the casing wall are contemplated, and they 1 will keep the mandrel assembly centered within the casing.

Interiorly of the sleeve 3 and above the blocks 7 there is formed an annular groove having an upwardly and inwardly tapered side wall, and a series of clutching segments 9 are axially slidably fitted within the internal groove and formed with tapered outer surfaces to mate and bear on the tapered or wedge surface of the groove. These contractible clamps 9 are suitably keyed in place by means of axial keyways formed in their tapered surfaces to receive inwardly extended ends of studs it screw threaded through the sleeve 3 from the outside thereof. Coil springs 11 between adjoining bottom walls of the internal grooves and clutching segments 9 constantly urge the segments upwardly for an inward bias by the wedge surfaces to yieldably present their inner surfaces in tickler contact with the adjacent surface of the mandrel 1. These inner clutching surfaces are shown as having wickets or an axial succession of downwardly directed teeth to promote a one way clutching action and to bite or have a forceconcentrating engagement with the mandrel. In co-operation with the tapered hearing surfaces, the wickets enable downward movement of the mandrel with respect to the sleeve 3 to occur relatively freely but resist relative upward movement of the mandrel by more tightly wedging and clutching the mandrel and sleeve together. While not essential, the wicket teeth may be machined to follow a spiral lead and to form on the co-operating segments a screw thread contour, as illustrated in Fig. 8. Spiral teeth will be easy to machine and will facilitate rotational release of the parts, although a succession of circular ribs which are not in spiral continuity will also accommodate a backing out of the mandrel upon its rotation.

As best seen in Fig. 5, the upper end of the sleeve 3 is specially formed with an internal annular recess or counterbore and with stepped shoulder abutments 12-12 having upwardly and inwardly inclined or beveled end faces to mate with downwardly and outwardly inclined wedge faces of complementary stepped shoulder abutments 16-16 at the lower ends of a pair of segmental clamps or expansible shoes 15 of the main clutching or primary locking slip of the packer assembly. The upstanding annular wall of the recess has telescopically nested relation with the shoe wall or lower skirt extensions 14 of the expansible elements or shoes 15 of the main clutching or primary locking slip of the packer assembly and contains a number of circumferentially spaced and axially elongated slots for lost motion reception of radial connector pins 13--13 carried on the dependent lips or skirt extensions 14. Figs. 5 and 6 also show coil springs 17 surrounding the pins 13 between the overlapping ex tensions of the sleeve 3 and shoes 15 for exerting a retractive force on the shoes 15 and supplementing the retractive force of a gartercoil spring 18 situated within annularly aligned depressions in the outer faces of the several primary slip shoes.

Each expansion clamp or shoe 15 is interiorly formed with one or more axially extending wedge surfaces inclined upwardly and outwardly and with internal shoulders or lifter abutments for interlocking relation with corresponding external wedge and lifter shoulderson a relatively axially adjustable tubular sleeve'or wedge member 19. The wedge sleeve or shoe expander element 19, fitted between the expansible shoes 15 and the mandrel 1, has scured at its upper end abearing abutment or suspension ring 20 which for assembly purposes is constituted by two half segments and has a dependentskirt screw threaded interiorly of the wedge sleeve 19. It has an inwardly extending lift shoulder fitted within an annular groove of the mandrel 1 to slide therein and at times to bottom of the flatabutment shelf or lift shoulder at the lower end of the groove. The upper end of the mandrel groove is inclined downwardly and inwardly, and closely surrounding it, as well as the smaller diameter groove and the larger diameter portion of the mandrel above the groove, is a rubber packer collar or sleeve 21 whose internal diameter conforms when unstressed to the different diameter mandrel portions surrounded by it. Thus, as seen in Fig. 1, the packer has a lower wide zone of wall thickness and an upper narrow zone of wall thickness. The opposite end surfaces of the annular deformable wall constituting the packer 21 bear on and preferably are cemented or vulcanized to adjoiningend faces of the axially spaced apart

abutment rings

20 and 22. This upper abutment ring or collar 22 is rotatably secured to the mandrel 1, as by means of a complement of small rollers 23, such as antifriction bearings which project into aligned keyways or guide races on the inside of the ring 22 and the outside of the mandrel 1.

The assembly of parts as described, and in the packer contracted relation shown in Fig. l, is moved to location by lowering the drill string from the surface, and is drawn or pulled downwardly by the locked bayonet type pin 4 and slot 5 connection at the bottom of the sleeve 3. Downward pull is transmitted from the sleeve 3 through the pins 13 at their upper limits of lost motion. to the collapsed shoes 15 and by their flat shouldered connections to the primary wedge 19. The lower stop abutment for the ring 20 prevents excess tension force on the rubber packer 21, and the packer moves downwardly between its

end abutment rings

20 and 22 without axial compression force being applied thereto from the mandrel and its rotatably secured collar 22. In the descent, the parts are centered in the casing by the slide engagement therewith of the elastic shoes ,7, which are under a slight radial compression.

When the depth is reached at which the packer is to be set, the tubing string is backed up for the small distance necessary to raise the bayonet pin 4 from its seat in the J-slot 5, and the frictional braking connection of the shoes 7 on the casing wall tends to hold the sleeve 3 to the stationary casing 2. After the pin has been raised, a counterclockwise turning of the tubing string will place the pin in axial alignment with the open end of the J-slot and downward movement of the string relative to the frictionally braked sleeve 3, as permitted by the oneway clutching device 9, will lower the other parts until the primary slip shoes 15 bottom on the top .of the sleeve 3. The lost motion connection through the [pin 13 and its receiving slot accommodate this relative travel. Further descent of the tubing string, transmitted through the. collar 22, the packer 21, and the collar 20 to .the

primary wedge 19, will expand the main slip shoes or wall clamps 15 outwardly into tight clamping engagement with the wall of the casing 2 for fixedly locating the assembly at the selected depth to be packed olf. Shoe expansion will also be effected by the secondary wedging action afforded by the bearing abutment of the

mating wedge surfaces

12 and 16 at the overlapping portions of the shoes 15 and sleeve 3 for supplementing the Wedge action of the primary wedge 19. Thus the segmental wall clamp 15 is radially expanded or wedged outwardly by the slidable engagement with its oppositely tapered Wedge surfaces of the downwardly and inwardly inclined wedge surfaces of the primary wedge 19 and the upwardly and inwardly inclined wedge surfaces 12 at the upper end of the secondary wedge or bottoming sleeve 3 as an incident to relative travel toward one another of the axially spaced wedges or

clamp actuating members

19 and 3. Once theslip is set, the packersleevc 21 will have concentrated on it the downward movement of the string and will be subjected to endwise compression force as well as a radial force by reason of the relative downward travel of the tapered upper shoulder of the mandrel groove and the entry of the larger external diameter portion of the mandrel into the smaller internal diameter portion of the packer. By these combined axial and radial forces, the packer will be deformed outwardly or bulged between the

end abutment collars

20 and 22 into tight sealing relation with both the surface of the mandrel and the surface of the well bore casing.

With the setting of the packer as seen in Fig. 2, no reversal or upward pull of the tubing string will release the parts, for the reason that the one way clutching device 9 will make a more firm securement of the tubing String mandrel with the sleeve 3. Any upward force on the pipe 1 is transmitted through the clutch 9 to the secondary wedging sleeve 3, which then acts upwardly on the expansible slip 15 with the supplemental wedges 12 hearing more tightly against the lower end bevels 16 of the expanded shoes 15 for retaining the shoes against contraction and also exerting further expansion force thereon. Thus well generated forces, including those of vibrational character, insure a tight seal and one which is unlikely to break loose even under severe pounding.

Release of the packer can be easily accomplished by surface control and by simply applying a small lifting force on the string and simultaneously rotating it. While the wickets of the one way clutching device 9 resist a direct upward movement of the mandrel, they will permit mandrel rotation, and with a combined rotation and upward lift, the mandrel. will be threaded slowly upwardly. Mandrel rotation is accommodated by the antifriction bearings 23 at the upper packer thrust collar 22. As the mandrel is gradually raised, the compression force applied through the upper ring 22 is lessened on the elastic packer 21, which then elongates out of sealing relation. As that occurs, the wedges 19 draw back for retraction and release of the slip shoes 15. Upon complete release, tubing string rotation is stopped. It the packer is to be lowered, the

bayonet joint

4 and 5 is re-established; but should it be desired to lift the packer, there will be no need to relatch the bayonet connection, and upward travel of the tubing string will be transmitted through the shoulder connection with the ring 20 without strain on the rubber packing. The shouldered formations on the primary wedge 19 and the shoes 15 will lift those parts and the pin 13 will rise to the top limit of its slot in the sleeve 3 to pull it upwardly with the resilient centralizer blocks 7 again serving to ride on the casing wall and space the assembly therefrom.

While the foregoing specification deals only with a preferred embodiment, it will be apparent that the invention is .not to be limited to the exact disclosure and that the scope :of the invention is intended to cover equivalents as come within the scope of the appended claims.

What is claimed is:

1. A packer assembly including a mandrel for connection in a pipe string to be inserted in a well, a pipe centering sleeve on the mandrel, resiliently positioned bearing means on said sleeve for frictional contact with the wall of the well, a releasable latch to lock said sleeve to the mandrel during its insertion to a well depth to be packed off and releasable to accommodate relative mandrel movement While frictional wall contact holds said sleeve, a one-way clutching connection between the sleeve and the mandrel accommodating downward movement of the mandrel relative to the sleeve and resisting upward movement of the mandrel relative to the sleeve, said clutching connection including downwardly directed wickets to bite into the mandrel surface but accommodate mandrel rotation and an upward unthreading of the man drel relative to the sleeve, an expansible shoe having radial and axial lost motion connection with said sleeve and arranged to be expanded into binding contact with the well wall, mating wedge surfaces on said sleeve and said shoe to impart an expanding force on the shoe when a mandrel lifting force is transmitted through said clutching connection to the sleeve, 9. primary expander shoe wedge having wedge engagement with the shoe and exerting expansion force on the shoe upon downward expander wedge movement relative to the shoe, an elastic deformable collar above said wedge to transmit mandrel movement thereto for shoe expansion and a collar abutment rotatably secured to the mandrel for imparting downward mandrel movement on the collar which, after the shoe has been expanded into binding contact with the wall, is deformed between the wedge and said collar into packing relation with the mandrel and the wall and for accommodating mandrel rotation during said upward unthreading.

2. A vibration resisting assembly for packing the space between a well wall and a pipe string inserted in the well, including a pipe, a deformable collar surrounding the pipe, an abutment ring secured to the pipe at one end of said collar, an expander wedge at the other end of the collar, an expansible clamp co-operating with said wedge for expansion upon relative downward movement of the wedge, a secondary-expander wedge axially spaced from the first wedge and engageable with said clamp, and a one way clutching device between the secondary wedge and the pipe, operative to transmit pipe lifting force to said secondary wedge.

3. In a well packer, a central member, an elastic deformable packer collar sleeved thereon, a thrust ring bearing on one end of the collar and having a rotary connection with the central member through which axial force is transmitted, a clamp engaging wedge bearing on the opposite end of said collar, an expansible casing engageable clamp actuable by relative axial movement of said wedge, a sleeve surrounding the central member and having detachable connection therewith, a friction bearing element carried by the sleeve for a frictional anchorage with a surrounding casing when said connection is detached, a one-way clutching connection between said sleeve and said central member to resist upward movement of the central member relative to said sleeve, and mating wedging surfaces on the sleeve and clamp to resist clamp collapse under upward thrust of said member transmitted through said one-way clutching connection to said sleeve.

4. In a well tool of the character described, means to pack oif the annular space about a mandrel positioned within a well including a mandrel, slip expander wedges shiftably carried by said mandrel in axially spaced relation to one another and each having a wedging surface inclined in a direction opposite to that of the other, an

expansible slip positioned in the space between said wedges and provided with two sets of wedge engageable surfaces for mating co-operation with said inclined wedging surfaces in response to relative mandrel movement in either direction, a deformable 'packer collar in force transmitting relation with the mandrel and one of said wedges and responsive to mandrel movement in one direction to first shift the last mentioned wedge and thereby expand said slip and thereafter respond to further mandrel movement by bulging radially'and closing off the annular space around the mandrel and a one-way clutch connection between the other wedge and the mandrel and which clutch connection transmits mandrel movement in the opposite direction to said other wedge and maintains saidother wedge in position for blocking contraction of the previously set expanded slip.

5. In a Well tool for packing the annular space about a pipe, a pipe, an expansible slip, a primary slip expander wedge, a pipe carried abutment above the wedge, an elastic deformable collars between the wedge and said abutment serving first to transmit pipe movement to the wedge to set the slip and thereafter to deform between the Wedge and the abutment for sealing said space, a member below the slip for abutting engagement therewith and co-operating with the primary wedge to resist slip contraction, and a contractible slip connecting the slip bottoming member with the pipe to transmit upward thrust from the pipe to said slip bottoming member.

6. A vibration resisting well packing assembly for insertion in a Well to pack off the space interiorly of the wall of the well, including a mandrel, an expansible slip movably carriedby the mandrel for anchorage with the wall of the well, an upwardly acting wedge and a downwardly acting wedge, both carried by the mandrel and co-operatively related to the slip to expand the same upon relative slip and mandrel movement, an elastic deformable packer interposed between the mandrel and one of the wedges and arranged to transmit mandrel movement in one direction to the last mentioned wedge to set the slip and thereafter upon further mandrel movement to be deformed into packing-off relation to the mandrel and the well wall and a contractible slip engageable with the mandrel and the other of said wedges in transmitting mandrel movement in the opposite direction to the other of the wedges and in maintaining the wedge in position to resist contraction of said expansible slip.

7. In a well packer, a central member to be lowered into a well, a lower sleeve having sliding engagement and detachable draft connection with said central member and a peripheral bearing for frictional drag on the Wall of the Well, a one way slip connection between the sleeve and the central member operative to transmit lifting force from the member to the sleeve, an outwardly expansible well wall engaging shoe having a wedge surface to mate with a Wedge surface on the sleeve and expanding the shoe upon sleeve lifting movement, an upper shoe expanding wedge slidable on said central member, 'and a deformable collar between said wedge and a central mem-' ber carried abutment through which downward member movement after detachment of said draft connection will first set the Wedge and thereafter deform said collar to pack off the space between the central member and the well wall.

8. In a packer assembly to be lowered into a Well to seal off the annular space between inner and outer members and to be lowered on one of the members, a lowering member, a slip carried by the lowering member and shiftable radially for anchorage of the assembly to the other member, upper and lower oppositely tapered wedges engaging with oppositely tapered wedge surfaces of the shiftable slip in positioning the same upon relative wedge movement, a one-way slip connecting one of said wedges to the lowering member to move the wedge with the lowering member in one direction of lowering member movement while being ineffective for transmitting movement to the Wedge when the lowering member moves in the opposite direction, and a deformable packer interposed between the other wedge and an abutment on the lowering member and through which the other wedge is connected with the lowering member and is moved to slip setting position with lowering member movement in said opposite direction, said packer being arranged for sealing directions toward and from one another and engageable with said clamp to shift the same toward effective clamp ing position upon relative movement of the clamp actuating members in one of said directions, means joined to one clamp actuating member and arranged for co operation with a well wall in offering resistance to movement of said one clamp actuating member, a one-way clutching device interposed between said one clamp actuating member and the first mentioned member and arranged to transmit movement from said first mentioned member to said one clamp actuating member in only the direction relative to the other clamp actuating member as to cause shifting of the clamp toward its effective clamping position and a resilient connection including a deformable packer annulus interposed between said other clamp actuating member and said first mentioned member as a motion transmitting connection therebetween and which deforms to an enlarged diameter in response to motion of said other clamp actuating member relative to the clamp and in the direction which shifts the clamp toward its effective clamping position.

10. In a well packer as described in claim 9 wherein the movement resisting means is a friction bearing element to contact a fixed surface in the well for positioning saidone clamp actuating member as an axial stop abutment for the clamp during a clamp setting operation by relative movement of the other clamp actuating member in the direction in which the one-way clutching device is free.

11. The structure of claim 10 in which a releasable draft connection between the member to be lowered and said one clamp actuating member can be released for rendering the friction bearing element in condition to position the last mentioned member as a stop abutment.

12. The structure of claim 9 wherein the resilient connection also includes a rotatable bearing to accommodate rotation of the member to be lowered relative to the packer annulus and said one Way clutching device includes circumferentially extending teeth engaging the last mentioned member to enable an upward unthreading travel of the last mentioned member upon its rotation in packer set relation.

References Cited in the file of this patent UNITED STATES PATENTS 881,154 Robinson Mar. 10, 1908 1,802,786 Smith Apr. 28, 1931 2,404,692 Church July 23, 1946 2,421,399 Wilson et a1. June 3, 1947