Well packer and well production apparatus

Oct. 23, 1962 _{c c} br_Own 3,059,699

WELL PACKER AND WELL PRODUCTION APPARATUS

Filed April 17, 1958 2 Sheets-Sheet 1

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ATTGMEY

Oct. 23, 1962

C. C. BROWN

3,059,699

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attorney

United States Patent Office

3,059,699

Patented Oct. 23, 1962

3,059,699

WELL PACKER AND WELL PRODUCTION APPARATUS

Cicero C. Brown, % Brown Oil Tools, Inc., P.O. Box 19236. Houston, Tex.

Filed Apr. 17, 1958, Ser. No. 729,172

Claims. (CI. 166—187)

This invention relates to well packers and particularly to a hydraulic pressure-actuated packer and to a well production apparatus employing such packers..

A primary object of this invention is to provide an improved form of well packer which is set by hydraulic pressure and released by rotation of the pipe string on which it is mounted.

A principal object is to provide a form of packer in which the expansion of a resilient packer member is effected by the relative movement of a cylinder and piston elements secured respectively to the packer member and to the operating string in response to fluid pressure supplied from the interior of the operating string to the interior of the cylinder to compress or set the packer.

An additional object is to provide a packer employing a compressible resilient packing element operatively connected to an actuating head comprising a cylinder and a piston enclosed within the cylinder, relatively movable in response to hydraulic pressure introduced between the piston and the cylinder from the interior of an operating pipe string, the piston having port means for passage of hydraulic fluid therethrough from the pipe string, said port means being provided with check valve means for retaining the pressure introduced into the cylinder.

A further object is to provide a production apparatus for wells having a plurality of producing formations at different elevations, the apparatus comprising the combination with a pipe string insertible in the well bore, of a plurality of the packers in accordance with this invention mounted on the pipe string in positions adapted to isolate the producing formations from one another, and a plurality of sleeve valves mounted in the bore of the pipe string between the several packers and opposite the respective producing formations, said sleeve valves being arranged to be selectively opened or closed to permit flow of fluids from selected earth formations through the well string.

Other and more specific objects and advantages of this invention will become apparent from the following detailed description when read in conjunction with the accompanying drawing which illustrates useful embodiments in accordance with this invention.

In the drawing:

FIG. 1 is a view showing a well intersecting a plurality of fluid-producing formations at different elevations and having positioned therein production apparatus in accordance with this invention for selectively producing fluids from the several formations.

FIG. 2 is a longitudinal, partly sectional view of a well packer in accordance with this invention, the parts being shown in the unset or inactive position, as when being inserted in a well;

FIG. 3 is a view similar to FIG. 2, showing the parts of the packer in the set position; and

FIG. 4 is a view similar to FIG. 3, showing the parts of the packer in the packer-releasing position preparatory to withdrawal from the well.

Referring first to FIGS. 2 to 4, the packer in accordance with the present invention, designated generally by the letter P, comprises a tubular body or mandrel 10 having a bore 11 adapted to form a part of a production pipe string S, into which the packer is connected in a manner and by means which will be more fully described hereinafter. The lower end of the body 10 is provided

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with a section of external threads 12 received in the internally threaded bore of an adapter 13 by which the lower end of mandrel 10 may be connected into pipe string S. The upper end of adapter 13 forms an upwardly facing shoulder 15 about the lower end of body 10 and is adapted to provide a supporting stop for a collar 16, which, in turn, forms a base or support for a flexible, resilient annular seal element 17. The latter is provided with upper and lower lead end rings 18 and 19, respectively, lower end ring 19 being interposed between the lower end of seal element 17 and collar 16. Seal element 17 and end rings 18 and 19 are slidably positioned on body 10 so that when downward compression is applied against upper end ring 18, seal element 17 will be compressed against collar 16 and the resulting compression will expand the seal element radially outwardly, as is well understood in this art, to form a fluidtight seal with the surrounding well wall.

Disposed above upper end ring 18 and slidably surrounding mandrel 10 is a cylinder 20 having an enlarged bore 24, the lower end of which is closed by a head 21 which abuts upper end ring 18. Head 21 is provided with a central opening 22 to slidably receive mandrel 10. A packing ring 23, such as a conventional O-ring, is disposed in the wall of opening 22 to form a fluid-tight slidable seal between the cylinder head and the exterior of mandrel 10. Bore 24 is open at its upper end and adapted to slidably receive a tubular piston 25, having a central bore 27 through which mandrel 10 extends. The upper end of piston 25 projects above the open end of cylinder 2® and is provided with an internally threaded socket 26 for connecting the piston to an adapter 28 by which the piston may be connected into pipe string S. Below socket 26, the bore 27 of piston 25 is provided with a section of left-hand threads 29 which are adapted to mesh with mating threads 30 provided on the exterior of mandrel 10 adjacent its upper end. The section of threads 29 is made substantially longer than the section of threads 30, and below the lower end of threads 29, bore 27 is provided with an upwardly facing shoulder 31 adapted to engage the lowermost thread 30 to limit upward movement of piston 25 relative to mandrel 10 for purposes to be more fully described hereinafter. A threaded shear pin 32 of pre-determined breaking strength, is mounted in the wall of cylinder 20 near its upper end to project into a threaded socket 33 provided in the exterior of piston 25 at a point which permits the shear pin to lock the piston to the cylinder, and thence to the pipe string, when the piston is in a substantially fully inserted position within the cylinder. The connection between cylinder 20 and piston 25 formed by shear pin 32 initially prevents relative longitudinal and rotational movement between cylinder 20, piston 25 and pipe string S, and serves to hold cylinder 20 in non-compressing relation to seal element 17.

A circumferential groove 34 is cut in the exterior of piston 25 near its inner end and is adapted to receive annular sleeve 35, constructed of rubber or similar flexible, resilient material. Sleeve 35 has a length such as to fit freely in groove 34 and has a cylindrical bore 36 of a normal diameter such as to seat tightly against the bottom of groove 34. The bottom of groove 34 is countersunk at 37 to receive a split metal ring 38 adapted to form a support backing for sleeve 35. A port 39 extends radially through the wall of piston 25 to provide fluid communication between the bore of piston 25 and the bottom of groove 34 through a registering opening 40 provided in ring 38. A radial port 41 is provided through the wall of mandrel 10 positioned to be in registration with port 39 to thereby provide fluid communication between bore 11 of mandrel 10 and groove 34 through the

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Ο intervening passageway formed by port 39 and opening 40.

Sleeve 35 constitutes a normally closed, outwardly opening check valve adapted to control communication between bore 11 of the mandrel and bore 24 of cylinder 20. Thus, when fluid pressure in bore 11 exceeds that in bore 24, this differential pressure will act to force sleeve 35 outwardly away from the bottom of groove 34 sufficiently to allow pressure fluid to flow through ports 41, 39 and 40 and pass around the ends of sleeve 35 to enter bore 24. Conversely, a pressure differential in the opposite direction will compress sleeve 35 tightly against the bottom of groove 34 and prevent back-flow of pressure fluid and thereby serve to trap whatever pressure has been introduced into bore 24.

An annular packing 42, such as a conventional O-ring, is positioned about the exterior of piston 25 slightly above groove 34 to form a slidable fluid-tight seal between the piston and the wall of cylinder 20. A second annular packing 43, such as a conventional O-ring, is positioned in bore 27 at a point below port 39 to form a slidable fluid-tight seal between the piston and the exterior of mandrel 10. It will be seen that when piston 25 and mandrel 10 are in the relative positions shown in FIGS. 2 and 3, packings 23, 42 and 43, in cooperation with sleeve 35, Will act to trap between these packings any fluid pressure which may have been admitted into cylinder 20. The portion of bore 24 of the cylinder extending between the longitudinally spaced packings 23 and 42 forms a longitudinally extendible pressure chamber into Which pressure fluid may be introduced through the conduit means comprising the ports 39, 40 and 41 for urging the cylinder into axially compressive engagement with seal element 17. An annular packing 44 is provided between adapter 28 and socket 26 to seal between these connection elements.

Packer P, constructed as above described, is designed to operate in the following manner: When initially installed in pipe string S, the parts of the packer will be in the position illustrated in FIG. 2, in which piston 25 will be inserted in cylinder 20 and secured thereto by means of shear pin 32; ports 39 and 41 will be in registration and packing 43 will be disposed below the passage formed by the registering ports 39 and 41. When sufficient fluid pressure is developed in bore 11 of the mandrel, this pressure will be exerted through ports 41 and 39 against the inner surface 36 of sleeve valve 35 and will force the latter away from opening 40 sufficiently to allow the pressure to enter bore 24 of the cylinder. This pressure will, as previously noted, be trapped between packings 23 and 42 and will tend to urge the cylinder and piston apart. When sufficient pressure is thus introduced into bore 24 of the cylinder to exceed the breaking strength of shear pin 32, the latter will part (FIG. 3) and the pressure will then act to force the piston and cylinder apart. Since the piston will be connected to the pipe string, it will be held against movement relative thereto, and the pressure entering bore 24 will force cylinder .20 downwardly, thereby compressing seal element 17 against collar 16 and expanding the packer radially into sealing engagement with the surrounding well wall to seal off the space between pipe string S and a liner L forming the wall of the well. This set position of the packer is illustrated in FIG. 3.

To release the packer, the pipe string will be rotated in the right-hand direction. Threads 29 and 30 being left-hand threads, the right-hand rotation of the pipe string will cause piston 25 to move upwardly relative to mandrel 10. A slight upward pull may be applied to the pipe string to aid this movement. The upward movement of piston 25 relative to mandrel 10 will move the lower end of the piston upwardly until packing 43 has moved above port 41, whereupon pressure previously trapped, between packings 23 and 42 will escape through port 41 into bore 11 of the mandrel. Release of pressure from the interior of the cylinder will allow seal element 17 to retract by reason of its natural resilience and thereby release its sealing engagement with the wall of the well. Rotation of the operating string may be continued until shoulder 5 31 comes up against the lowermost thread 38, whereupon further rotation will act to rotate the cylinder as well as all of the operating string below this packer.

Where additional packers P are mounted on the pipe string below the uppermost packer P, the engagement of 10 shoulder 31 with the thread 30 of the uppermost packer will permit the continued rotation of the pipe string to be transmitted to the next lower packer where this rotation will become effective to release the next lower packer in the same manner as previously described. Thus, any 15 number of packers, such as packer P, may be mounted on the pipe string and may be released in succession by rotation from the top in the manner described.

Referring now to FIG. 1, there is shown an apparatus employing two packers Pi and P₂ of the construction pre20 viously described, in an assembly to be inserted in a well W, having a plurality of fluid producing formations F_bF₂ and F₃ at different elevations along the well bore. The apparatus is constructed and arranged to permit production of fluids from selected ones of the formations. As 25 illustrated, well W is equipped with the liner L having a series of perforations H_b H₂ and H₃ opposite the respective formations Fj, F₂, and F₃. Pipe string S has mounted thereon the packers Pi and P₂, one at a point between formations Fx and F₂ and the other at a point between 30 formations F₂ and F₃ whereby to isolate each of the formations from the others when the packers have been set as shown. Above packer Pj and opposite perforations H₁₍pipe string S is fitted with a sleeve type valve, designated generally V_1; comprising tubular valve casing C_x adapted ³⁵ to form a part of pipe string S. Casing Cj is provided with ports Gi through the wall thereof to provide communication between the interior of valve casing Cj and the bore of liner L. A valve sleeve Vx is longitudinally slidable in the bore of casing Οχ relative to ports Gx to ⁴⁰ control the flow of fluid through ports Οχ. The specific details and the particular form of valve Υχ do not form a part of this invention, as such sleeve valves are entirely conventional and their construction and operation will be fully understood by those skilled in this art. Valves V₂45 and V₃, identical in construction to valve Vx, are positioned in pipe string S, respectively, between packers Ρχ and P₂ and below the latter. Thus the valves Vx, V₂and V₃ are positioned to control communication between the bore of the pipe string and the respective earth forma50 tions Fx, F₂ and F₃. At its lower end pipe string S is fitted with a tubular tail piece section T having an annular upwardly facing seat A in the bore thereof to receive a plug Q, which is adapted to be dropped through the bore of pipe string S in order to close the lower end 55 of the bore. Plug Q carries a set of anchor slips K which anchor the plug against upward displacement from seat A.

The apparatus illustrated in FIG. 1 is employed in the following manner: Packers Ρχ and P₂, and valves Vx, 60 V₂ and V₃ will all be installed in the relative positions as illustrated in FIG. 1 and the apparatus will then be lowered into the well and into liner L to a point at which the packers and the valves will be in the positions relative to the several producing formations as illustrated. G5 when the apparatus is first introduced into the well, plug Q will not be in place, so that when the apparatus has been lowered to the desired position in the liner, fluid circulation may be set up through the bore of the pipe string and thence upwardly outside the pipe string through the '' bore of the liner to the surface to thereby wash the well preparatory to putting it into production. Thereafter, plug Q will be lowered through the bore of the pipe string to rest upon seat A in order to close off the lower end of 73 the bore of the pipe string. Valves V₁₍ V₂ and V₃ may

3,059,699 all be in their closed positions during the washing operation. After the plug is in place, hydraulic fluid, such as water or oil, will be pumped into the bore of pipe string S and its pressure built up to such a point as will set packers P_x and P₂, in the manner previously described, 5 and thereby seal off the bore of liner L between the perforations communicating with formations F_x, F₂ and F₃, as illustrated. When this has occurred, the pressure trapped in cylinders 24 of the respective packers will remain therein and continue to hold packers P_x and P₂ in 10 their expanded or sealing positions until subsequently released. After all the packers are set, a valve-actuating tool D, of suitable and generally conventional construction, adapted to move the valve sleeves longitudinally in the valve casings, will be run into the well on a wire line 15 E and manipulated in a suitable and generally conventional manner to move one of the valve sleeves to the valve-opening position. The particular sleeve valve which thus may be opened may be any one of the several valves and will ordinarily be the lowermost valve in the string. 20 Upon opening the valve, actuating tool D will be withdrawn from the well and fluids from the related earth formation thus placed into communication with the pipe string will flow into the pipe string and thence to the surface. Production of fluid from the selected forma- 25 tion may thus be continued until that formation is exhausted, the other valves being kept closed in the -meantime and the packers being maintained in the expanded position by the pressure fluid which had been trapped in their respective cylinders. To initiate production from 30 another formation, tool D may be run back into the well and manipulated to close the previously-opened valve and to then open another of the valves in the string to thereby place its corresponding formation in production.

Thus, the apparatus heretofore described may -be used 35 to successively produce a number of fluid-producing formations until all have been exhausted. It will be understood, of course, that, conditions permitting, more than one earth formation may be produced at the same time.

When production from all of the several formations 40 has been exhausted, the apparatus may be removed from the well simply by rotating pipe string S to retract pistons 25 in their respective cylinders 20, in the manner previously described, to thereby successively release the several packers from their sealing engagement with liner L. 45 When all of the packers have been thus released, the entire string may be withdrawn from the well.

Instead of employing a tail pipe T having an open bore which may then be closed by means of plug Q, the lower end of the pipe string may be closed by a permanent 50 closure and the apparatus assembly may be run into the well with one or more of the sleeve valves in the open position so that washing of the well may be conducted through the open valve rather than through the open lower end of the pipe string. 55

From the foregoing, it will be seen that the invention above described provides a relatively simple hydraulic pressure-actuated packer which requires a minimum amount of manipulation to set it, since it requires only the application of fluid pressure through the interior of 60 the operating pipe string, and that the invention further provides a simple apparatus employing a plurality of the described packers in combination with relatively simple sleeve valves to provide a means for selectively producing formation fluids from a plurality of earth formations with- 65 out requiring the removal of the pipe string or any part thereof when necessary or desirable to switch production from one formation to another.

It will be understood that various modifications and variations may be made in the details of the illustrative. γθ embodiments within the scope of the appended claims, but without departing from the spirit of the invention.