|Publication number||US3152643 A|
|Publication date||Oct 13, 1964|
|Filing date||Mar 19, 1962|
|Priority date||Mar 19, 1962|
|Publication number||US 3152643 A, US 3152643A, US-A-3152643, US3152643 A, US3152643A|
|Original Assignee||Erwin Burns|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (2), Referenced by (17), Classifications (11)|
|External Links: USPTO, USPTO Assignment, Espacenet|
E. BURNS LINER HANGER Oct. 13, 1964 2 Sheets-Sheet 1 Filed March 19. 1962 .5 W56@ MU OC- 13, 1964 E. BURNS 3,152,643
LINER HANGER Filed March 19, 1962 2 Sheets-Sheet 2 .II/Ga 4a INVENTOR.
//ew/N Bae/v5 GEN r.
United States Patent O 3,152,643 LINER HANGER Erwin Burns, Los Angeles, Calif. (8346 Salt Lake Ave., Bell, Calif.) Filed Mar. 19, 1962, Ser. No. 180,691 4 Claims. (Ci. 166-124) This invention relates to an oil well production tool and is more particularly concerned with a tool for setting pipe, tubing, or casing within a cased well bore, and commonly known as a liner hanger.
In the practice of completing oil wells it is customary to suspend a liner within the casing. This liner consists of a length of perforated pipe supported at its upper end in the lower end of the casing by means of a device commonly known as a liner hanger. The length of perforated pipe extends below the casing and into the uncased well bore. It is an object of the present invention to provide a liner hanger by which a liner may be readily lowered into a well bore in a simple and effective manner, and in the operation of which the liner may be supported without the necessity of rotation while the slips of the hanger are set and without imposing any weight on the setting tool or the liner.
It is a further object of the present invention to provide a liner hanger carrying a packing element which cannot be accidentally disturbed or distended until the tool which is used to set the liner hanger has been released and the Weight of the liner is imposed directly on the slips of the hanger.
Another object of this invention is to provide a liner hanger construction having several important and novel improvements over the liner hanger construction disclosed in Patent No. 2,337,733, issued December 28, 1943, to Erwin Burns and Frank C. Boyd, entitled Liner Hanger. In the above construction, structure is provided to maintain the construction assembled when running into a well which includes a radially outwardly projecting annular flange at the center of the central body portion of the hanger defining an upwardly disposed shoulder and a radially inwardly opening annular recess or relieved portion in the barrel portion of the hanger which carries the slips and which defines a downwardly disposed shoulder upon which the flange stops. Such a construction makes the central body portion costly to manufacture and requires that the wall thickness of the said barrel, and the wall thickness of the packer cage, be materially reduced to an extent that only large diameter hangers having parts with considerable initial wall thickness can be manufactured in accordance with the teachings of this patent.
Still further, the above patented construction requires a special packer cage having unsupported extremely thin wall portions in order to establish a seal about the central body portion of the construction, and such that it is subject to `failure when subjected to severe working conditions.
It is an object of this invention to provide novel means and structure for maintaining a liner hanger construction of the character referred to assembled when the construction is lowered into a well or when it is being pulled therefrom.
It is an object of this invention to provide a structure of the character referred to wherein the wall thicknessv of the various parts going to make up the construction need not be reduced to such a extent as to weaken the construction or make it impossible or irnpractical to establish small diameter tools in accordance with the invention.
In the constructions of the type here concerned with and provided by the prior art, the body extends through 3,l52,643 Patented Get. 13, 1964 ice the packer cage and connects with the liner. An actuating ring is carried by the body to engage a deformable packer. When the tool is actuated, the weight of the liner is exerted through the ring onto the packer to distend it and in such a way that the liner and body assembly is supported wholly by the actuating ring, which is fixed to the body and rests on the deformable packer. The actuating ring is such that only point contact is made by it on the body. As a result, the weight of the liner frequently causes separation between the ring and the body and the liner with the body separates from the hanger and packer cage, drops into the well bore and renders the entire construction inoperative and the well incapable of being produced.
It is an object of my invention to provide a secondary stop means to limit downward movement of the body relative to the cage, independent of the actuating ring for the packer and including opposing stop shoulders on the cage and the body.
Still another object of my invention is to provide a liner hanger construction of the character referred to wherein a separate seal is provided between the packer cage and the central body portion of the construction, so that the packer, per se, need not seal with the body and so that the packer cage need not be established with the weak, unsupported thin-walled portions which are subject to failure.
The present invention contemplates the provision of a setting tool having a barrel, a removable stem associated therewith, slips carried by the barrel and normally held in retractedrposition but capable of being released by manipulation of the stem to set against the casing, and a deformable packer carried by the barrel and adapted to be distended into a sealing position when the weight of the liner is imposed upon the structure, after the slips have set.
The various objects and features of my invention will be fully understood from the following detailed description of a typical preferred form and application of my invention, throughout which description reference is made to the accompanying drawings, in which:
FIG. 1 is a longitudinal sectional view of the construction provided by the present invention;
FIG. 2 is a longitudinal sectional view of my new construction showing it in an actuated position;
FIG. 3 is an enlarged detailed sectional view of portion of the construction that I provide;
FIG. 4 is a transverse sectional View taken as indicated by line 4-4 on FIG. l;
FIG. 5 is a transverse sectional view taken as indicated by line 5-5 on FIG. 1;
FIG. 6 is a transverse sectional view taken as indicated by line 6--6 on FIG. l;
FIG. 7 is a transverse sectional view taken as indicated by line 7-7 on FIG. 1; and
FIG. 8 is an exploded perspective view showing the packer cage and actuating ring provided by the invention.
Referring particularly to FIGS. l and 2 of the drawings, 10 indicates a Well casing which is set within a well bore 11 and within which a liner hanger 12 is arranged. The li-ner hanger includes a square mandrel or stem 13 which is threaded into the lower end of a drill pipe joint 14. This stem is of square cross `section and has a lower threaded end 15 which receives `a nut 16. The nut 16 is internally threaded at 17 and may receive 'the threaded end of a length of tubing through which circulating fluid or cement may be forced downwardly into the liner. The square stem 13 extends through a liner nut 18 of the setting tool. This nuit has a central bore therethrough of square cross section, as indicated `at 19, through which the stem 13 may slide while positively engaging the nut to impart rotation thereto. The exterior surface of the lower cylindrical portion of the liner nut is formed with threads 20. The threads are square lefthand threads. The upper length of the nut is cylindrical, as indicated at 21, and has a central cylindrical counterbore 22 above the square stem opening 19. This cylindrical portion is externally threaded at 23 to receive an annular bearing nut 24. The bearing nut has a lower shoulder forming a ball race Z which rests upon an anti-friction bearing 26, here shown as being of the ball bearing type. The `anti-friction bearing 26 rests upon the upper end face of a sleeve 27 of the setting tool. This sleeve is cylindrical and is formed at its lower end with a frusto-conical face 28. A cylindrical bore 29 is formed in the sleeve and the sleeve has a running fit with the upper cylindrical portion 21 of :the nut 18.
Extending downwardly from the ysleeve 27 are a plurality of separate slip engaging iingers 32 which are mounted on the outer circumference of the sleeve 27 and overhang the screw portion 20 of the nut 18, as clearly illustrated throughout the drawings. Four of these fingers are here shown and their purpose in the structure will be hereinafter described.
The liner hanger includes a tubular body 34 having an upper portion 34 and a lower portion 34" of reduced diameter. The upper portion 34 is internally threaded yat its upper end as indicated at 35, the threads being complementary to the threads Ztl on the nut 18. The
upper end of the body is formed with a flat, radially disposed upper or top end 36. Slidably mounted upon the upper portion 34 of the body 34 is a tubular slip barrel 37 which iits over the body and is provided with a radially inwardly projecting annular stop flange 38 at its upper end which `opposes and rests against the upper end 36 of the body.
The upper end 36 of the body thereby provides a rest for `the slip barrel 37. The upper end of the slip barrel is provided with a tapered end face 39 which face extends or continues radially inwardly across the top of the stop liange 38 and opposes the face 28 on the sleeve 27.
Formed within the cylindrical outer face of the slip barrel 37 are guideways which receive wickered slips 41. These slips are designed to move upwardly and outwardly in the guideways 40 as urged by a plurality of springs 42 mounted at the heel of the slips. The lingers 32 nor-V mally engage the upper ends of the slips and when the sleeve 27 is in its lower position, force the slips downwardly and hold them retracted so that they will not grip the wall `of the casing 10 until released.
The lower end of the upper portion 34' of the body establishes a downwardly disposed stop shoulder 36.
The lower end of the slip barrel 37 is internally threaded as indicated at 45. This receives the upper threaded end of a packer cage 46. This cage is shown particularly in FIG. 8 of the drawings, where it will be seen to have a flat upper end establishing an upwardly disposed stop shoulder 46 and `a substantially cylindrical central body portion 47. The lower end of lthe cage is provided with an enlarged collar 48. The central body portion of the cage is cut away at intervals about its circumference, as indicated at 49, and has longitudinal wall portions 50 between the cut-away portions. The upper end of the portion of the cage is threaded, as indicated at 51, and is threaded into the threaded bore 45 of the slip barrel 37. The inside diameter of the cage is less than the inside diameter of the barrel and substantially the same as the outside diameter of the lower portion 34 of the body. It will be seen from the above that the shoulder 46 established by the top of the cage opposes the shoulder 36 established by the lower end of the upper portion 34 of the body. It will also be seen that due to the fact that the enlarged collar 48 is of a diameter somewhat greater than the diameter of the body 47, a square shoulder 52 is established in a plane at right tangles to the longitudinal axis of the packer cage. Cast around the exterior of the body portion 47 of the cage and filling the openings 49 is a sleeve-type packer 53. This packer may be of `any desired design or construction and any suitable deformable material, such for example, as lead or rubber.
By reference to FIG. 7 it will be seen that the packer sleeve is cylindrical and of an outside diameter agreeing with that of 4the enlarged collar 48 of the cage. The inside diameter of the packer :sleeve indicated at 54, lits snugly on the exterior of the hanger body 34 where the openings 49 occur, las clearly illustrated in the drawings. The length of the packer is .such as to insure space for a packer actuating ring 55. The actuating ring 55 is shown in detail in FIG. 8 of the drawings. Here it will be seen to comprise an annular wall 56. The outer diameter of this section agrees with the normal outside diameter of the packer sleeve and the outside diameter of the slip barrel 37. Actuating lugs 57 extend inwardly from the annular portion 56 of the ring and are spaced at equal intervals therearound. The lugs 57 iit into the upper ends of the slotted openings 49 in the packer cage to engage the hanger body 34, and are fixed to the body 34 Aas by welding W. The packer sleeve 53 is of a length. shorter than the openings 49 suflicient to permit the lugs 57 to assume a position in the ends of the openings 49 and resting against the upper end face of the packer sleeve 53.
Attention is directed to the fact, as shown in FIG. l of the drawings and as indicated above that the inside diameter of the cage, as indicated at 58, is substantially the same as the outside diameter of the lower portion 34 of the body 34, and establishes sliding engagement therewith.
The lower collar 48 of the cage is provided with an annular radially inwardly opening channel 78 in which is arranged an annular yO-ring type seal 71, which seal establishes sealing engagement about the exterior of the body 34, below the packer 53. With this relationship of parts, it will be apparent that when the tool is fully actuated, as shown in FIG. 2 of the drawings the, packer 53 establishes Huid-tight seal-ing engagement with the interior of the casing and with the shoulder 52. on the collar 48 to prevent the passage of uid longitudinally through the annulus defined by the casing and the tool, and that the sealing ring 71 carried by the collar and engaging the body, establishes a iiuid tight seal between the body and the collar and prevents the passage or leakage of fluid between the cage and the body, and between the portions of the packer occurring in the openings in the cage and the body.
The lower end of the body 34 extends downwardly below the cage 46 and a desired distance and is externally threaded at 59 to receive a coupling collar 60 into which is threaded the upper end of a perforated liner 61.
Before use, the structure is assembled as shown in the ldrawings by placing the packer cage on the body member 34 with the ring 55 disposed above the sleeve 53. Thus the under face of the ring 55 will extend entirely across the upper face of the packing sleeve 53. The slip barrel 37 is then attached to the top of the packer cage 46 by threading the portion 51 ot' the packer cage into the threaded section 45 of the barrel 37. When thus threaded the shoulder 38 of the slip barrel will engage the top of the body 34 and will limit the downward movement of the slip barrel 37 relative to the body and the shoulder 36 and the body will be spaced above the shoulder 46 on the cage. The liner nut 18 carrying the slip 27 is then threaded into position within the upper end of the body member 34 and by engagement of the threads 20 on the nut with the threads 34' of the body member. When the nut is tightened into position the tapered face 28 of the sleeve 27 will rest against the upwardly presented tapered face 31 on the slip barrel. It will be understood that when this assembly is made the sleeve 37 does not rotate since the lingers 32 extend longitudinally into the recesses 44 in the slip barrel 37. While thus held the nut 18 is tightened and will move the fingers 32 downwardly to engage the upper ends of the wickered slips 41. These slips will be held in their retracted position so long as the nut is tightened to its seated position. Attention is directed to the fact that while the nut 18 is rotated as by the mandrel 13, the body 34 is stationary and produces an advantage to be more clearly set forth hereinafter.
When the structure is assembled as directed, la perforated liner 61 is attached to the lower end of the tubular body 34 by a coupling 60. The structure is then ready to be lowered into the bore of an oil well and to be set relative to the casingr 10.
In operation of the invention the liner hanger is assembled and set as shown in FIG. 1 of the drawings, and is ready to be run into the well bore. It is to be pointed out that in the event the lower end of the packer cage 46 should strike an obstruction or meet resistance while being lowered into the casing, this will have no effect on the tool and the entire tool will remain in its set assembled position, since the packer cage 46 is directly connected to the slip barrel through the threaded connection 45, and the slip barrel in turn is held against longitudinal movement by bearing against the sleeve 27, which is held by the hanger nut 18. It will therefore be seen that no amount of end thrust on the packer cage 46 will ever deform the packer 53. When the structure is lowered into the well, it will be understood that the liner 61 is `in place on the lower end of the liner hanger body 34. Due to the length of the stem 13 it is possible for the hanger to have considerable longitudinal movement on the stem so that the hanger and the liner may be manipulated suciently to facilitate the handling of the table slips or other means used at the surface level. When the liner has reached the desired point of setting in the well rotation of the drill pipe 14 to the right will impart similar rotation to the square stem 13, and will result in positive rotation of the hanger nut 18. The nut will then advance longitudinally upwardly. This movement will correspondingly move the sleeve 27 upwardly. As previously explained, the sleeve 27 carr-ies the fingers 32. These will move upwardly and away from their abutting engagement with the top of the slips. This will permit the springs 442 to force the slips upwardly and outwardly into engagement with the inner face of the casing 10. Excessive downward movement of the ring, such as might occur if the packer were caused to flowrexcessively, is prevented when" the shoulder 36 engages and stops against the shoulder 46. This stopping action prevents further downward movement of the ring and further distending of the packer. The above stopping action also prevents separation of the body from within the cage, should the ring separate from the body.
After the sleeve 27 has been elevated to a point where the fingers 32 are retracted from the grooves 32 further rotation of the stem 13 will completely disengage the sleeve and the nut 18 from -the hanger body 34 and will permit it to be removed from the well with the drill string 14.
From the foregoing description it will be seen that under noI circumstances can the packer be `set until the setting tool has been at least partially removed, and that prior to such time the packing element will be held positively against any longitudinal movement.
The present design of liner setting tool does not require the use of special separate tools or the use of more than one string of pipe since the liner is directly carried on the liner `setting tool and the tool is directly carried upon a single string of pipe. The invention also involves the novel feature of insuring that the slips are disposed above the packer and that they are directly actuated by the application of the weight of the liner to the deformable packing independently of the slips.
With the construction set forth above it will be seen that the packer sleeve 53 is relied upon or depended upon to seal between the exterior of the cage and the interior of the casing only, and that the sealing ring '71 serves to seal between the cage and the body 34. Accordingly, the longitudinal wall portions 50 of the cage 46 need not be spaced from the body 34 and have their wall thickness reduced, but, rather, can be of substantial wall thickness and bear against and iind support on the body 34. Further, the packer 53 need only extend about the exterior of the cage and into the openings 49, and need not extend between the longitudinal wall portions 50 of the cage and the body 34.
An extremely important advantage afforded by the present invention resides in the fact that the flange 38 at the upper end of the barrel overlies the upper end of the body and protects the body and the threads therein from being split and changed by the introduction of body tools and the like into the construction, after it is set.
Having described only a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims.
Having described my invention, I claim:
l. A combination liner hanger and packer comprising an elongate tubular body adapted to support a liner at its lower end and having an upper portion with ilat upper and lower ends and a lower portion of reduced diameter, a tubular slipbarrel having a radially inwardly projecting flange at its upper end slidably receiving the upper portion of the body with the upper end ofthe body normally engaging the stop flange, detachable means normally engaging the upper end of said body and by which it is supported from a string of pipe, slips carried on the slip barrel to engage the wall of a casing through which the hanger extends, a rigid slotted packer cage having at upper end secured to the lower end of the slip barrel and slidably engaged about the lower portion of the body, a deformable packer carried by and surrounding the cage, and an actuating ring fixed to the body and surrounding the cage to engage the packer, whereby when the detach-V able means is detached the slips are set and the hanger body moves downwardly with relation to the barrel and the cage and imposes the weight of the liner upon the upper end of the deformable packer to deform the same into sealingV engagement with the casing and the lower v end of the upper portion of the body seats on the upper end of the cage.
2. A combination liner hanger and packer comprising an elongate tubular body adapted to support a liner at its lower end and having an upper cylindrical portion with flat upper and lower ends and a lower portion of reduced diameter, an elongate tubular slip barrel having a radially inwardly projecting stop flange at its upper end and slidably receiving the upper end of the body with the upper end of the body normally engaging the stop flange, the lower end of the upper portion of the body terminating above the lower end of the barrel, detachable means normally engaged with the upper end of said body and by which it is supported from a string of pipe, slips carried on the slip barrel to engage the wall of the casing through which the hanger extends, an elongate rigid slotted packer cage having a flat top and being smaller in inside diameter than the inside diameter of the barrel and threadably engaged in the lower end of the slip barrel with its upper end normally spaced below the lower end of the upper portion of the body and slidably engaged about the lower portion of the body, a deformable packer carried by and surrounding the cage, and an actuating ring fixed to the body and surrounding the cage to engage the packer, whereby when the detachable means is detached, the Slips are set and the hanger body moves downwardly with relation to the barrel and the cage and imposes the weight of the liner upon the upper end of the deformable packer to deform the same into sealing engagement with the casing and the lower end of the upper portions stops on the upper end of the cage, and
l? sealing means between the cage and the body and including an annular groove in the body and an O-ring in the groove and engaging the body.
3. A combined liner hanger and packer comprising an elongate tubular body having an upper portion with at upper and lower ends and a lower portion of reduced diameter adapted to support la liner at its lower end, a tubular slip barrel having an upwardly disposed end face and an annular radially inwardly projecting stop shoulder at its upper end and slidably receiving the body with the upper end of the body normally engaging the stop shoul der, the lower end of the upper portion of the body normally terminating above the lower end of the barrel, said barrel carrying casing engaging slips movable longitudinally of its outer face, an elongate rigid slotted cage smaller in inside diameter than the inside diameter of the barrel and threadably engaged in the barrel and defining an upwardly disposed stop shoulder, said cage depending.
from the barrel and slidably engaged about the exterior of the lower portion of the body and having a radially outwardly extending upwardly disposed stop shoulder at its lower end, an actuating ring slidably engaged about the exterior of the cage to normally occur at the upper end thereof and having radially inwardly projecting lugs projecting through the slotted cage and fixed to the body and a deformable packer sleeve engaged about the cage between the ring and the shoulder at the lower end of the cage, a support for the hanger detachable means carried by the support to releasably engage the body and t cooperate with the end face on the barrel and with the body to hold the body and barrel against relative longitudinal movement, means carried by the detachable means for releasably holding the slips in retracted position until the detachable means is detached, whereupon the slips are released to set with a casing surrounding the hanger and packer, whereby the barrel is fixed against rotation and the hanger body is released to impose its weight and the weight of the liner through the ringand upon the deformable packer to distend the packer radially into sealing engagement with the casing and to shift the lower end of the upper portion of the body downwardly into seated engagement on the stop shoulder delined by the upper end of the cage.
4. A combination liner hanger and packer comprising an elongate tubular body having an upper portion with at upper and lower ends and a lower portion of reduced diameter adapted to engage and support the liner at its lower end, a tubular slip barrel having an upper end face and an annular radially projecting stop shoulder at its upper end and slidably receiving the body with the upper end of the body normally engaging the stop shoulder and with its lower end normally spaced above the lower end of the barrel, said barrel carrying casing engaging slips movable longitudinally of its outer face, an elongate rigid slotted cage smaller in inside diameter than the inside diameter of the barrel and having its upper end threadably engaged in the lower end of the barrel and depending therefrom, the upper end of the cage being flat and defining an annular upwardly disposed stop shoulder, the lower end of the cage being fixed to the upper end of an elongate liner, said cage having a radially outwardly extending upwardly disposed shoulder at its lower end, yan actuating ring slidably engaged about the exterior of the cage to normally occur at the upper end thereof and having radially inwardly projecting lugs projecting through the slotted cage and fixed to the body and a deformable packer sleeve engaged about the cage between the ring and the shoulder, and an annular sealing ring carried by the cage at the lower end thereof and sealing with the body, a support for the hanger, detachable means carried by the support for engaging the body and temporarily cooperating with the upper end face on the barrel and with the body to hold the body and barrel against relative longitudinal movement, and means carried by the detachable means for releasably holding the slips in retracted position until the detachable means is detached, whereupon the slips shift and set with a casing surrounding the barrel, whereby the barrel is xed with the casing and against axial shifting and rotation and the hanger body is released to impose its weight and the weight of the liner through the ring and upon the deformable packer to distend the packer radially into sealing engagement with the casing and to shift the lower end of the upper portion of the body downwardly into seated stopped engagement with the shoulder defined by the upper end of the cage..
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|U.S. Classification||166/124, 166/196, 166/208|
|International Classification||E21B23/06, E21B43/02, E21B23/00, E21B43/10|
|Cooperative Classification||E21B23/06, E21B43/10|
|European Classification||E21B43/10, E21B23/06|