US3421449A - Gas lift well production apparatus - Google Patents

Description

Jan. 14, 1969 c. B. COCHRAN 3,421,449

GAS LIFT WELL PRODUCTION APPARATUS Original Filed Oct. 11, 1965 Sheet 4 of 5 7' Z 0:14 flue s M ATTORNEYS Jan. 14, 1969 c. B. COCHRAN 3,421,449

GAS LIFT WELL PRODUCTION APPARATUS Original Filed Oct. 11, 1965 Sheet g of 5 Jan. 14, 1969 c. B. COCHRAN 3,421,449

GAS LIFT WELL PRODUCTION APPARATUS Original Filed Oct. 11, 1965 Sheet 3 of a 52m 2 5 2a m a", aw 7 COQI/RAN fly 13% gfioza. 1 (4414- ATrokA/Q's 1969 c. B. COCHRAN GAS LIFT WELL PRODUCTION APPARATUS Sheet 4 of 5 Original Filed Oct. 11, 1965 //////l /f/] III Jan. 14, 1969 C. B. COCHRAN GAS LIFT WELL PRODUCTION APPARATUS Original Filed Oct. 11, 1965 lll/l/llll/l/l/ll///llllll/II/lIII/l/j/j'll/l/ll-I///// Sheet ,Q of 5 147' TOR/MEX? United States Patent 3,421,449 GAS LIFT WELL PRODUCTION APPARATUS 'Chudleigh B. Cochran, Houston, Tex., assignor to Cicero C. Brown, Houston, Tex.

Original application Oct. 11, 1965, Ser. No. 494,686, now Patent No. 3,373,816. Divided and this application Oct. 10, 1967, Ser. No. 674,294

US. Cl. 103-233 2 Claims Int. Cl. F04f 1/12 ABSTRACT OF THE DISCLOSURE Apparatus for insertion in a well bore or casing for the production of well fluids by the use of gas injection. The invention includes a novel system utilizing injector type tubing inserted into the well from a spool or the like, with gas lift valves attached to the tubing during insertion thereof into the well.

This application is a division of application Ser. No. 494,686, filed Oct. 11, 1965, now Patent No. 3,373,816, by the same inventor.

This invention relates to apparatus for installing gas lift valves in a well, and more particularly, to apparatus for installing such gas lift valves in a well by using injector tubing.

The use of gas lift valves in the production of oil and other fluids is well known. For example, see Lester Charles Uren, Petroleum Production Engineering, Chapter III, pp. 158-214 (2nd Ed., McGraw-Hill Book Company, Inc.). Gas lift valves are conventionally interposed in jointed production tubing and may be utilized to produce a formation fluid either through the production tubing or through the annulus between the tubing and the casing.

During the installation of gas lift valves by conventional methods and with conventional equipment, it is necessary to make up joints of tubing with gas lift valves interposed at desired intervals. Since many wells are quite deep, a great deal of time is consumed in making up the joints of tubing and interposing the valves. If valves are to be serviced after installation, it becomes necessary to either Withdraw the tubing from the well with work-over equipment or to use a wire line rig and run the risk of breaking the small diameter wire in the well and having to fish out the lost portion. The workover equipment needed to effect installation and withdrawal is necessarily bulky and expensive, and the time requirements compound the expense.

One apparatus for injecting a continuous length of tubing into a well is taught in US. Patent No. 3,116,781 issued J an. 7, 1964, and entitled, Apparatus for Completion and Working Over of Wells.

Accordingly, it is an object of this invention to provide novel apparatus for installing gas lift valves into a well without the necessity of making up a plurality of joints of conventional tubing.

Another object is to provide apparatus for installing gas lift valves in a well which do not require the use of expensive conventional work-over equipment.

Yet another object is to provide a faster system of completing a well for gas lift operations, and once completed, for pulling and servicing the valves.

Still another object is to provide apparatus for completing a well for gas lift without complete disassembly of well head equipment such as a Christmas tree.

An additional object is to provide apparatus permitting the attachment of gas lift valves to a continuous length of tubing.

3,421,449 Patented Jan. 14, 1969 The inventive method as claimed in the aforesaid Ser. No. 494,686 may be generally described as a method of installing gas lift valves and appurtenant tubing in a well which includes the steps of inserting through a well head a length of substantially inflexible tubing which is fed into the well from a reel of tubing proximate the well head; attaching a body to the tubing which carries a gas lift valve adapted to communicate with the tubing; and feeding an additional length of tubing into the well to position the gas lift valve at the desired depth.

Briefly stated, the apparatus of this invention is in a gas lift well production system comprising the combination of a length of injector type tubing arranged for supporting in a well to be produced, at least one gas lift valve, means for attaching the valve to the tubing during insertion thereof into the Well, and conduit means for conducting gas between the interior of the tubing and the valve while the valve is supported in the well by the tubing.

Typical apparatus of the invention may be described as a clamp having pivotally mounted tubing encompassing members which permit the clamp to be opened, placed about the tubing and closed thereabout. Means are carried by the clamp for securely fixing the clamp about the tubing and means are also provided for mounting a gas lift valve on the clamp to permit communications between the gas lift valve and the tubing.

To be more specific, reference is now made to the drawings in which:

FIG. 1 is a cross-sectional view of a well with injector tubing inserted therein.

FIG. 2 is a cross-sectional view similar to FIG. 1 showing a severed length of injector tubing which has been suspended in the well to permit attachment of a gas lift valve by interposition.

FIG. 3 is a cross-sectional view similar to FIG. 2 which illustrates injector tubing containing a plurality of interposed gas lift valves.

FIG. 4 is a cross-sectional view similar to FIG. 3, but additionally illustrating the connection of the tubing to a gas source and the packing elements which seal the tubing within the well.

FIG. 5 is a partial cross-sectional view of a mandrel which is adapted to be interposed in a length of injector tubing.

FIG. 6 is a cross-sectional view along line 66 of FIG. 5.

FIG. 7 is a view in elevation of one embodiment of an apparatus which permits connection of :a gas lift valve to a continuous length of tubing.

FIG. 8 is an elevational view of the FIG. 7 embodiment rotated clockwise relative to a plan view of FIG. 7.

FIG. 9 is a cross-sectional view along line 9-9 of FIG. 8.

FIG. 10 is a cross-sectional view along line 1010 of FIG. 9.

FIG. 11 is a cross-sectional view of a well illustrating a plurality of the apparatus illustrated in FIGS. 7-10 which have been attached to a length of injector tubing.

FIG. 12 is a partially cutaway view 'in elevation of an alternative embodiment of the invention which in many respects resembles the embodiment illustrated by FIGS. 7-10.

Referring now to FIG. 1, in particular, a well is generally provided with surface structure such as a well head 1 which is mounted on casing 2 and from which depends production tubing 3. A plurality of suitably valved flow lines 4 may communicate with the tubing and, typically, the annulus between the casing 2 and tubing 3 can be communicated with external surface equipment through suitably valved conduits 5. The annulus between the casing 2 and tubing 3 is typically packed off by a packer 6 so that any fluids entering casing 2 through perforations 7 therein may be produced through production tubing 3. The perforations 7, of course, communicate with the producing formation 8.

When the producing formation 8 discontinues production under natural energy it becomes necessary to apply external energy and it is with a system of applying such energy that this invention is concerned. That system of supplying external energy is, as has been mentioned, the use of gas lift valves. To feed tubing and the gas lift valves to be attached thereto into the well, an apparatus 9 such as taught in US. Patent No. 3,116,781 issued Jan. 7, 1964, and entitled, Apparatus for Completion and Working Over Wells is positioned proximate the well head 1. Apparatus 9 includes means (not illustrated) for driving drum 11 so that the injector tubing 12 carried about the drum is fed into well head 1, as illustrated in FIG. 1.

The end of injector tubing 12 is closed by any suitable method and when a desired length of tubing 12 has been inserted into tubing 3, as illustrated in FIG. 2, slips 13 are seated against frusto-conical shoulder 14 for grippingly supporting the injector tubing 12. Tubing 12 is severed thereby forming ends 15 and 16 between which is interposed a mandrel 17 equipped with a conventional gas lift valve 18. The detail of conduit 17 with attached gas lift valve 18 is better illustrated in FIG. 5, to which reference is here made.

In FIG. 5, the mandrel 17 includes a conduit 19 which at both ends is provided with identical structure, and for convenience, like parts at each end will be given the same reference numerals and the structure at only one end will be described. The upper end of conduit 19 has secured thereto by any conventional means an externally threaded collar 21. Collar 21 defines a cylindrical recess 22 which has a greater internal diameter than the outer diameter of tubing 12 to which conduit 19 is aflixed. Recess 22 receives an annular sleeve 23 which is provided with a radially extending flanged portion 24, which abuts the corresponding shoulder 25 of collar 21. Sleeve 23 and collar 21 define therebetween an annular space within which end 16 of tubing 12 is received. Disposed about tubing 12 is an O-ring type seal 26 above which is carried an annular washer 27.

Also placed and spaced about tubing 12 are a plurality of slips 28, as particularly illustrated in FIG. 6, which have oblique outer surfaces 29 that taper radially inward toward the tubing 12 oriented end of the collar 21 as illustrated. Carried about slips 28 is an annular slip ring 31 provided with a mating oblique surface 32 which also tapers radially inwardly toward the tubing 12 oriented end of collar 21. To permit slip ring 31 to be forced downward to drive slips 28 into engagement with end 16 of tubing 12 and thereby fixedly secure end 16 between slips 28 and sleeve 23, tubing 12 loosely carries an annular connector 33 provided with threads adapted to mate with the threads on collar 21. Connector 33 has a recess 35 which terminates in a shoulder 34. As collar 21 is threadably engaged with connector 33, by relative rotation, the slips 28 will be driven into engagement with end 16 of tubing 12. Sleeve 23 serves as a supporting element to prevent collapse of end 16 as slips 28 move radially inward. While tubing 12 is substantially inflexible, it nevertheless is flexible to a degree to permit feeding from drum 11 and could collapse radially inward if too great a pressure was applied.

As slips 28 move radially inward they will move downward to some extent causing washer 27 to deform O-ring type seal 26 to insure an adequate fluid seal between c-onduit 19 and tubing 12.

Conduit 19 intermediate its ends carries a lug 36 and brackets 37 and 38 which support a conventional gas lift valve 18. Typical of valves which may be used are the Maccd valves illustrated in the 1964-65 Composite Catalog of Oil Field Equipment and Services, pp. 3032- 3035. Valve 18 communicates with the interior of tubing 12 through a recess 39, passageway 40 and aperture 41.

To attach mandrel 17 to tubing 12 by interposition, mandrel 17 is positioned between ends 15 and 16 which are inserted at their respective ends of mandrel 17 between sleeves 23 and slips 31. The collars 21 and connectors 33 are threadably engaged, as described above, thus securely interposing the mandrel 17 and gas lift valve 18 in tubing 12.

Once mandrel 17 has been interposed in tubing 12, slips 13 may be removed from well head 1 and an additional length of tubing 12 fed into the well. Should it be necessary to interpose other mandrels 17, the slips 13 are again placed in well head 1 and another mandrel 17 with gas lift valve 18 is interposed as described above.

As particularly illustrated in FIG. 3, a plurality of the mandrels 17 may be interposed. Once the desired num ber of mandrels 17, at the desired spacing, have been interposed in tubing 3, slips 13 are set and packing elements 42 are sealingly set in well head 1 by threadable engagement of sleeve 43.

The tubing injector apparatus 9 is removed and tubing 12 is coupled to a source of pressurized gas 44. Gas lift valves 18 then function in a conventional fashion to aid production of formation fluid through the annulus between injector tubing 12 and production tubing 3.

Another, and presently more preferred, embodiment of apparatus permitting attachment of a gas lift valve to the injector tubing 12 is illustrated in FIGS. 7-10.

The alternative apparatus illustrated in FIGS. 7-l0 includes a clamp 45 having arcuate tubing encompassing members 46 and 47 which are pivotally mounted by a pin 48. Pin 48 passes through registering hinge portions 49 and 51 of members 46 and 47, respectively.

Members 46 and 47 are securely fixed to tubing 12 by means of Allen screws 52, or the like, which threadably engage member 46 moving the members 46 and 47 radially inward. Member 47 is provided with a scored surface 53, as particularly illustrated in FIGS. 9 and 10, for grippingly engaging tubing 12.

Clamp 45 is provided with an integral lug 54 and brackets 55 and 56 Which retainingly receive a conventional gas lift valve 57, such as the Macco valves referred to above. Lug 54 is provided with a recess 58 which through passageway 59 and aperture 61 in tubing 12, permit communication between the gas lift valve 57 and the interior of tubing 12. To assure a seal between the clamp 45 and tubing 12, member 46 carries an imbedded circular resilient seal 62 which has a curved face to assure engagement with the exterior of tubing 12.

To attach the clamp 45 to tubing 12, a portion of tubing 12 is run into the well head 1 as illustrated in FIG. 1, the end of tubing 12 being closed. An aperture 61 is drilled in tubing 12 at a desired spot and the members 46 and 47 are pivotally opened and placed about tubing 12. When passageway 59 has been registered with aperture 61, the members 46 and 47 are pivotally closed and fixedly secured to tubing 12 by threadable engagement of screws 52. An additional length of tubing 12 may be fed from drum 11, and when a desired length has been reeled from the drum, another aperture may be drilled in tubing 12 and another clamp 45 attached.

FIG. 11 illustrates a length of tubing 12 to which a plurality of the clamps 45 have been attached.

Once a desired number of clamps 45 have been aflixed, as illustrated in FIG. 11, the well head 1 is packed off as described before and tubing 12 is connected to a source of pressurized gas.

Another, and presently most preferred, embodiment of the invention is illustrated in FIG. 12. In FIG. 12, two clamps 63 and 64 are provided. Clamp 63 includes arcuate tubing encompassing members 65 and 66 which are pivotally mounted by pin (not illustrated) in much the same manner as members 46 and 47 of the previously described embodiment. Clamp 63 through member 66 retains the top of gas lift valve 68, the bottom of which is carried by member 69 of clamp 64. Clamp 64, like clamp 63, comprises members 69 and 71 pivotally mounted by a pin (not illustrated).

Member 69 of clamp 64 retainingly receives the gas lift valve 68, and through the recess 74 and passageway 75 therein, permits the gas lift valve 68 to communicate with the interior of tubing 12 through aperture 61.

The FIG. 12 embodiment is assembled on tubing 12 in much the same manner as the embodiment illustrated in FIGS. 7-10, except clamp 63 is fixedly secured by screws 76 after passageway 75 has been registered with aperture 61 and clamp 64 has been secured to tubing 12 by similar engagement of its screws 76.

A plurality of the embodiments illustrated in FIG. 12 may be used in the same manner as was described in connection with the embodiment illustrated in FIGS. 7- 10. The well head 1 is packed off in the previously described manner and tubing 12 communicated with a gas source.

While the embodiments illustrated in FIGS. 7-10 and 12 utilize a hinge as a means for mounting the tubing encompassing members, various other means may be employed. For example, the two members may be joined by a dovetail type connection or another suitable mechanical expedient.

Because in a typical well the spacing between gas lift valves may be 700 feet, it is less time consuming and more economical to feed substantial lengths of continuous tubing into the well and apply gas lift valves as desired than to make up conventional joints of tubing between which are interposed mandrels carrying gas lift valves.

By use of the apparatus of the present invention gas lift valves may be attached rapidly and at desired intervals. With the preferred embodiment of the invention, it is not even necessary to sever the tubing to attach a gas lift valve. As will be obvious from the above, the inventive apparatus may be used to produce through tubing 12 rather than through the annulus between tubings 12 and 3.

While rather specific terms have been used to describe several embodiments of the methods and apparatus of the present invention, they are not intended nor should they be construed as a limitation on the invention as defined by the claims.

What is claimed is:

1. In a gas lift well production apparatus, the com bination comprising:

a continuous length of injector type tubing suspended in a well to be produced, said tubing having a plural ity of ports through the wall thereof at vertically spaced apart intervals;

a plurality of gas lift valves supported by said tubing, with one said valve being associated with each of said ports;

a bracket arranged for connecting each of said valves to said tubing, each of said bracket including a pair of clamp members pivoted about a vertical shaft means and arranged for clamping about and frictionally engaging the outside surface of said tubing adjacent one of said ports, means for connecting said valve to said bracket, a passageway communicating between said valve and said port, and seal means for sealing between said passageway and said port with said seal means being held in seal ing engagement as an incident to the clamping 01 said clamp members about said tubing;

whereby said valves may be connected to said brackets and said brackets attached to said tubing during insertion of said tubing into said well by pivotally closing said clamp members about said tubing to thereby sealingly couple said valves with said ports.

2. The invention as claimed in claim 1 including:

means connected to said clamp members for controlling the extent of frictional pressure applied to said tubing by said clamp members.

References Cited UNITED STATES PATENTS 1,710,937 4/1929 McCarty 103-233 X 1,744,361 1/1930 Carlisle 103-232 2,144,144 1/1939 Crickmer 103-232 2,251,244 7/1941 Stanley 103-232 X 2,323,893 7/1943 Boynton 103-232 X 2,342,301 2/1944 Peters 103-232 X 3,116,781 1/1964 Rugeley et a1. 72-160 DONLEY I. STOCKING, Primary Examiner. WARREN J. KRAUSS, Assistant Examiner.

U.S. Cl. X.R. 103-232

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