US3212579A

US3212579A - Apparatus for automatic gas lift operation of oil wells

Info

Publication number: US3212579A
Authority: US
Inventors: Cryer Del
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-09-02
Filing date: 1959-09-02
Publication date: 1965-10-19
Anticipated expiration: 1982-10-19

Description

Oct. 19, 1965 D. cRYER APPARATUS FOR AUTOMATIC GAS LIFT OPERATION 0F oIL WELLS Filed Sept. 2, 1959 2 Sheets-Sheet 1 IN V EN TOR.`

DEL CRYER BY.' lo

WSL

ATTORNEY Oct. 19, 1965 D. CRYER 3,212,579

APPARATUS FOR AUTOMATIC GAS LIFT OPERATION OF OIL WELLS Filed Sept. 2, 1959 2 Sheets-Sheet 2 Tim'. 5

INVENTOR.'

DEL CRYER ATTORNEY United States Patent 3,212,579 APPARATUS FOR AUTOMATIC GAS LIFT OPERATIN 0F OIL WELLS Bel Cryer, Giddeus-.Jane Bldg., Shreveport, La. Filed Sept. 2, 1959, Ser. No. 837,630 4 Claims. (Cl. 166-52) This invention relates to an apparatus for automatic gas lift operation of oil wells.

Gas lift operation of oil wells in the past has been wasteful of equipment and gas when operated individually, and unsatisfactory in performance and also wasteful of gas when operated in groups.

Therefore i-t is an object of my invention to provide apparatus for the gas lift operation of oil wells, either singly or in groups, which is economical to manufacture and gives improved performance.

Other and further objects and advantages of my invention will be apparent from the following specication taken in conjunction with the accompanying drawings, wherein corresponding characters of reference designate the same or similar parts throughout the several views, and in which:

FIG. 1 is a diagrammatic layout view of the apparatus employed in my system.

FIG. 2 is a schematic wiring diagram of the apparatus shown in FIG. l.

FIG. 3 is a side elevation of the automatic high pressure multiple outlet valve employed in my system.

FIG. 4 is a top plan view of the valve shown in FIG. 3.

FIG. 5 is a fragmentary vertical cross sectional view of the valve shown in FIG. 3, with parts broken away.

FIG. 6 is a fragmentary plan view of lthe valve shown in FIG. 3, with parts broken away.

FIG. 7 is a horizontal cross sectional View taken along the line 7 7 in FIG. 5, on an enlarged scale.

Referring more in detail to the drawings, an important feature of my invention is the automatic high pressure multiple outlet valve 10, the details of which will be describer hereinafter. Sullice it to say at this point that the valve is provided with a plurality of outlets t0 be connected, respectively, to the several wells to be operated as a group, here shown as four in number and designated as 11, 11a, 11b and 11C. As is customary in the art, each of the wells is provided with a casing 12, a two inch tubing 13 inside the casing, and a one inch tubing 14 inside the two inch tubing. An outlet of the valve is connected to supply gas under pressure to the two inch tubing in each of the wells by means of the

pipe lines

15, 15a, 15b and 15C, respectively.

Another feature of my invention is that the one inch tubing at the top of each well is provided with an upward extension 16 beyond the coupling 17 at which the pipe line 1S takes off the gas and oil coming up from the well through the one inch tubing 14. Similar extensions 16a, 1Gb and 16C, couplings 17a, 17b and 17C, and pipe lines 18a, 18h and 18C are provided for the wells 11a, 11b and 11e, respectively. The extension 16, which is of course axially aligned with the one inch tubing, is connected at its upper portion to one end of a small one-quarter inch tubing 9 which is connected at its other end to the pipe line 18. Similar connections are provided as shown at 19a, 19b and 19C on the other wells.

The purpose of the extension 16 on the upper end of the one inch tubing and the by-pass connection 19 is to provide a shock absorber for the rabbit customarily employed in gas lift operation of oil wells, and the functioning of this device will be explained hereinafter.

The

pipe lines

18, 18a, 18]) and 18C may be connected directly to a gas and liquid separator, or they may be connected into a header 20 and thence through a commou pipe line 21 to the gas and liquid separator 22 3,212,579 Patented Get. 19, 1965 ICC which will be recognized by those skilled in the art as a separator of prior art construction.

Liquid from the gas and liquid separator 22 is conducted by pipe line 23 to the oil and water separator 24, of conventional construction, from which waste water is taken by means of the conduit 25, and oil passes by means of the conduit 26 to the oil storage tank 27.

Gas from the gas and liquid separator 22 passes by means of pipe line 28 through the scrubber tank 29 and thence by pipe line 30 to the inlet side of the motor driven compressor 31 which supplies gas under pressure through the pipe line 32 in response to actuation of the pressure responsive switch which is set to maintain pressure in the tank 33 between 500 p.s.i. maximum and 290 p.s.i. minimum, for example. Shut-olf valve 35 is manually operated to be closed if it is desired to make repairs or changes in the valve 10. The multiple outlet valve 10 is automatically operated in response to electric timer 36 to supply operating gas under pressure through the

pipe lines

15, 15a, 15b, 15C, selectively, to the wells being operated.

Another feature of my invention is that excess gas from the gas and liquid separator 22 which is not needed immediately for return to the gas storage tank 33, instead of being released as was previously done, is conducted by pipe line 38 into the casing of at least one of the wells for temporary storage under pressure, the pressure being controlled at about 15 p.s.i. by mean of pressure relief valve 39 in the pipe line 38.

Referring more particularly to FIGS. 3 through 7 in the drawings, it will be seen that my automatic high pressure multiple outlet valve comprises a cylindrical body 40 provided with a plurality of

outlet ports

41, 41a, 41b and 41o communicating respectively with

pipe lines

15, 15a, 15b and 15e. The valve body 4t) is closed at the bottom by bottom plate 42 and is closed at the top by top plate 43. The bottom plate 42 is supported upon a base plate 44 which is supported above floor plate 45 by a plurality of legs 45.

Interiorly, the valve body 4) is provided with a rotor 47 which :is journaled for rotation at 48 and 49 in the top :and bottom plates, respectively. The rotor 47 has an outer periphery conforming closely to the inner periphery of the valve body 40 except in one small portion of its periphery, here shown as about the rotor is cut away along ia substantially straight line to form la cavity Sli between the rotor and the inner periphery of the valve body. Extending radially inward from the cut away portion of the periphery, the valve body is provided with a radial bore 51 which extends past the center of the rotor. Through the hub journaled at 49 is the bottom plate 42, the valve body is provided with an axial bore 52 which at its inner end is in `communication with the radial bore 51 and at its outer end is in communication with pipe line 37 through swivel connections 37. A Teflon plug or bushing 5S having an enlarged head 56, making it somewhat mushroom shaped, is provided with a through bore 57 axially thereof and is carried in the radial bore 51 in the rotor 47 with the outwardly extending ange of .the underside of the enlarged head abutting the flattened cut away portion of the periphery of rotor 47. O ring S3 around the shank of the plug 55 prevents leakage from the radial bore 51 into the cavity 50 while permitting slight sliding movement of the plug 55 in the radial bore 51. The outer face of the Teflon plug or bushing 55 rests snugly against the inner periphery of the cylindrical valve body 40. In order to press the Teflon bushing 55 firmly ragainst the inner wall of the valve body, the inner end of the Tellen bushing which is received within the bore 51 is abutted by a collar 58 which is pressed thereagainst by coil spring 59, the collar 58 being slidably positioned within the bore 51. The other end of the coil spring 59 is engaged over a floating plug 60 which is slidably mounted in a radial bore 51. The rotor is tapped and threaded to receive an adjusting screw 62 which loosely engages the floating plug 60 for in and out movement thereof to adjust the tension on spring 59 pressing the collar 58 and plug 55 outwardly against the inner periphery of the valve body 40. A screw driver or other tool may be inserted through one of the outlet ports in valve body for adjustment of the screw 62, this end of the radial bore 63 being closed by a pipe plug 64 after the adjustment has been made and until the next adjustment is necessary.

Extending upwardly from the rotor 47 through the journal at 48 is the rotor drive shaft 65 which is connected by

gears

66, 67 through speed reducer 63 to the valve motor 69, the valve motor and speed reducer being mounted upon an upper plate 70 supported by a plurality of legs 71 mounted on the base plate 44. The gear 66 is provided on its upper face with an index plate 72 which carries a plurality of index lugs 73, one for each outlet in the valve body, and one for each space between outlets, eight such lugs being here shown (FIG. 6) spaced 45 apart corresponding to the spacing of the four outlets and four intermediate spaces in the embodiment of the valve yas shown. The index lugs are arranged to engage the actuating finger 74 of the micro-switch 75.

In the operation of the foregoing system according to my invention, assuming that the rotor 47 in the multiple outlet valve 10 is aligned with the Teflon bushing 55 overlying the outlet port 41, gas underpressure will pass from storage tank 33 through line 37 to the axial inlet bore 52 in the valve 10 and thence through the radial bore 51 and Teiion bushing 55 to the outlet port 41 with which the pipe line is connected to supply the gas under pressure to the two inch tubing in the well 11. The gas under pressure then passes down through the two inch tubing 13, opens the customary bottom hole gas lift valve (not shown), and enters the lower end of one inch tubing 14 to force the customary rabbit therein upwardly and carrying with it the accumulated iluid (gas and oil) which is taken off through the pipe line 18 at the coupling 17 until the rabbit passes the coupling 17. Thereafter, without the provision of my extension 16 on the one inch tubing, there would be a great hammering of the rabbit against the upper end of the tubing, but according to my invention the tubing 16 permits the rabbit to climb past the coupling 17 and the small amount of liquid remaining above the rabbit is forced out through the small one-quarter inch diameter tubing 19 which forms Ia by-pass back around the pipe line 18, this small by-pass tubing permitting the remaining liquid carried above the rabbit to escape slowly and thereby provide a cushioning effect for the rabbit which after coming to a stop, -again descends to the bottom of the well through the one inch tubing to pick up another accumulation of fluid. This operation continues for the programmed time set on the timer 36 for lifting fluid from the well, and as gas continues to be supplied through the pipe line 15 the rabbit continues to operate up and down in the one inch tubing carrying above it each time a slug of iiuid to be delivered through the pipe line 18 into the gas yand liquid separator 22, the oil and water passing therefrom through the pipe line 23 into the oil and water separator 24 from whence the oil passes through the conduit 26 into the oil storage tank 27. Meanwhile, back at the gas and liquid separator 22, the gas passes out through the pipe line 2S, through the scrubber 29 where any condensate is taken out, and thence through the pipe line 30 to the inlet side of the motor driven compressor 31 which supplies compressed gas through the pipe line 32 to replenish the supply in the storage tank 33 so as to maintain the pressure therein approximately between 500 p.s.i. maximum and 290 p.s.i minimum. Connected in parallel with the inlet side of the motor driven compressor 31 is the pipe line 38 which has its other end connected into the casing on well 11, for example, so that any gas coming through the pipe line 28 and not immediately needed or required by the inlet side of motor driven compressor 31 is temporarily stored in the casing 12 of wall 11, thus providing a closed, recycling system for the utilization and storage of the gas coming from the oil iield as an incident to the lifting of oil from the wells therein. Each of the other wells, in which gas is not being stored, is provided with a gas let-off pipe line 181:1, 181b, 181C, respectively, interconnecting the associated well casing with its associated pipe line to the gas and liquid separator 22, each such let-olf pipe line being provided with a check valve, as shown, to permit gas under pressure to flow from the well casing to the separator 22, but not reversely. It will be noted in FIG. 2 that the motor driven compressor 31 is connected across the electric supply line to supply gas under pressure to the storage tank 33 any time required in response to the actuation of the pressure controlled switch 34 mounted on the tank 33. It will Ialso be noted that upon the elapse of the programmed time for the lifting of oil from well 11, the associated switch in the timer 36, which according to the prior art may have a plurality of cam operated switches, one for each of the lugs 73 on the multiple outlet valve 10, will be closed; and upon the closing of any one of the parallel connected switches in the timer 36 switch 101 will be closed whereby a circuit is established through the contacts of normally closed, thermal delay switoh 102 and through the valve motor 69, thus permitting valve motor 69 to start running, even though the micro switch on the valve is at that instant held open by an index lug 73 on the valve, but upon running of the motor 69 to index the valve 10, microswitch 75 will promptly close to complete a circuit in parallel with the contacts of switoh 102 which at that time is still closed because of the thermal delay; however, after a predetermined period of time the thermal time delay relay coil of switch 102 will open the contacts of that switch, but the relay coil of that switch 102 will continue to be excited until the timer 36 progresses suiciently to close the parallel connected switch therein which it had just opened. Meantime, the valve motor 69 continues to run and index the multiple outlet valve 10 until micro-switch 75 is opened upon contact of its actuating finger 74 with the next index lug 73 which will open the micro-switch 75 and break the circuit to the valve motor 69. At this time the rotor 47 in the multiple outlet valve 10 is aligned with the Teflon bushing 55 midway between the outlet port 41 and the outlet port 41a, assuming that the direction of rotation is clockwise, although it could be counterclockwise. In this position the bore through the Teflon bushing 55 is sealed off tightly against the inner periphery of the valve body 40, being urged thereagainst by the spring 59 and by the pressure of the operating gas against the end of the bushing 55 in the radial bore 51, so that the flow of operating gas under pressure is completely shut off by the multiple outlet valve.

When the programmed time elapses for the waiting period before lifting oil from the next Well, the timer 36 will close the parallel connected switch therein associated with that phase of the operation so as to again close switch 101 to complete a circuit through the contacts of normally closed thermal delay switch 102 and through the valve motor 69, thus permitting valve motor 69 to start running again and the indexing of the valve 10 proceeds as before until the micro-switch 75 is opened upon contact of its actuating finger 74 with the next index lug 73 which will open the micro-switch 75 and break the circuit to the valve motor 69 when the rotor 47 in the multiple outlet valve 10 is aligned with the Teflon bushing 55 overlying the outlet port 41a, Ias shown in FIG. 7, thereby resetting the mechanism to supply gas under pressure for the predetermined programmed length of time as determined by the setting of the cams in the timer 36, which after the programmed time will close the parallel connected micro-switch therein associated with that phase of the operation to again initiate operation of the valve motor 69, as before, to index it to a position such that the Teilon bushing 55 is again sealed off against the inner Wall of the valve body 40, this time midway between outlet ports 41a and 41b. This cycle of operation continues throughout the 360 rotation of the multiple outlet valve, the valve body being provided with as many outlet ports as are necessary to accommodate the number of wells on the lease, it being understood that two index lugs 73 are provided for each such outlet port, one to align the rotor with the outlet port and the other to align the rotor with the wall median between adjacent ports, and it will also -be understood tha-t any or as many of the outlet ports may be closed off as desired, and any scheduled stops may be eliminated by merely removing the corresponding lug, or lugs, 73, and of course the programming of the entire cycle of operations, and all phases thereof, are fully and independently adjustable for suitable programming to meet the demands and desires of the operator.

Having thus described my method and apparatus for automatic gas lift operation of oil Wells, it will be apparent to those skilled in the art that the method and apparatus which I have provided is highly efficient, entirely automatic, and economical in the use of gas in this closed system which provides for the recycling yof the operating gas and the temporary storage of excess gas in one of the wells on the lease, but that many modications and changes may be made without departing from the spirit or scope of my invention as defined by the app-ended claims.

I claim:

1. Apparatus for automatic gas lift operation of a plurality of oil wells having an outer casing, intermediate tubing within said casing and inner tubing within said intermediate tubing, comprising a multiple outlet valve with an outlet connected respectively to the intermediate tubing in each of said Wells for supplying operating gas under pressure thereto selectively, a gas and liquid separator connected to receive gas and liquid from the inner tubing in each of said wells, an oil and water separator connected to receive liquid from said gas and liquid separator and adapted to separate oil from water and separately discharge the same, an operating gas storage tank operatively connected to supply gas under pressure to said valve, pump means operably connected to supply and maintain gas under pressure in said storage tank within predetermined limits, pipe means interconnecting said pump means with the gas outlet of said gas and liquid separator for supplying gas to said pump means, and a pipe line interconnecting the casing in one of said wells with the gas outlet of said gas and liquid separator for conducting excess gas from said gas and liquid separator to said one of said wells for temporary storage of excess gas therein.

2. Apparatus according to claim 1 wherein said valve is indexed in selectively supplying gas to said wells and including motive power means and timer means operiatively connected to said valve for indexing said valve to supply operating gas under pressure to said wells according to a predetermined program.

3. Apparatus -according to claim 2 including a bleed-oit valve operatively connected to the pipe line interconnecting the casing of said one of said wells with the gas outlet of said gas and liquid separator.

4. Apparatus for automatic gas lift operation of la plurality of oil wells having an outer casing, intermediate tubing within said casing `and inner tubing wit-hin said intermediate tubing, comprising a multiple outlet valve with an outlet connected respectively to the intermediate tubing in each of said Wells for supplying operating gas under pressure thereto selectively, said valve being indexed in selectively supplying gas to said Wells, a gas and liquid separator connected to receive gas and liquid from the inner tubing in each of said wells, an oil and Water separator connected to receive liquid from said gas and liquid separator and adapted to separate oil from Water and separately discharge the same, an operating gas storage tank operatively connected to supply gas under pressure to said valve, pump means operatively connected to supply and maintain gas under pressure in said storage tank within predetermined limits, pipe means interconnecting said pump means with the gas outlet of said gas and liquid separator for supplying gas to said pump means, motive power means and timer means operatively connected to said valve for indexing said valve to supply operating gas under pressure to said Wells according to a predetermined program, a pipe line interconnecting the casing of said one of said wells with the gas outlet of said gas and liquid separator and a bleed-oit valve operatively connected to said pipe line.

References Cited by the Examiner UNITED STATES PATENTS 971,612 10/10 Holliday 103-52 1,520,737 12/24 Wright 166-6 1,798,774 3/31 Yates 166--75 X 1,812,267 6/31 Lewis 166--6 2,034,798 3/36 Clark 166-2 2,309,075 1/43 Hill 166-7 2,570,553 10/51 Hawley 166-6 2,623,596 12/52 Whorton et al. 166-7 2,624,410 1/53 Nixon 166-75 2,741,265 4/56 Poor 137-625.11 2,773,551 12/56 Warden et al. 166-75 2,806,486 9/57 McDonald etal. 137-625.11 X 2,821,998 2/58 Mayhew 137-625.11 2,994,372 8/61 Stone 166-7 OTHER REFERENCES Uren, Lester C.: Petroleum Production Engineering, Oil Field Exploitation, 2nd edition, New York, McGraw- Hill, 1939.

CHARLES E. OCONNELL, Primary Examiner. BENJAMIN BENDETT, Examiner.

Claims

1. APPARATUS FOR AUTOMATIC GAS LIFT OPERATION OF A PLURALITY OF OIL WELLS HAVING AN OUTER CASING, INTERMEDIATE TUBING WITHIN SAID CASING AND INNER TUBING WITHIN SAID INTERMEDIATE TUBING, COMPRISING A MULTIPLE OUTLET VALVE WITH AN OUTLET CONNECTED RESPECTIVELY TO THE INTERMEDIATE TUBING IN EACH OF SAID WELLS FOR SUPPLYING OPERATING GAS UNDER PRESSURE THERETO SELECTIVELY, A GAS AND LIQUID SEPARATOR CONNECTED TO RECEIVE GAS AND LIQUID FROM THE INNER TUBING IN EACH OF SAID WELLS, AN OIL AND WATER SEPARATOR CONNECTED TO RECEIVE LIQUID FROM SAID GAS AND LIQUID SEPARATOR AND ADAPTED TO SEPARATE OIL FROM WATER AND SEPARATELY DISCHARGE THE SAME, AN OPERATING GAS STORAGE TANK OPERATIVELY CONNECTED TO SUPPLY GAS UNDER PRESSURE TO SAID VALVE, PUMP MEANS OPERABLY CONNECTED TO SUPPLY AND MAINTAIN GAS UNDER PRESSURE IN SAID STORAGE TANK WITHIN PREDETERMINED LIMITS, PIPE MEANS INTERCONNECTING SAID PUMP MEANS WITH THE GAS TO SAID PUMP MEANS LIQUID SEPARATOR FOR SUPPLYING GAS TO SAID PUMP MEANS, AND A PIPE LINE INTERCONNECTING THE CASING IN ONE OF SAID WELLS WITH THE GAS OUTLET OF SAID GAS AND LIQUID SEPARATOR FOR CONDUCTING EXCESS GAS FROM SAID GAS AND LIQUID SEPARATOR TO SAID ONE OF SAID WELLS FOR TEMPORARY STORAGE OF EXCESS GAS THEREIN.