US2746395A

US2746395A - Gas lift system

Info

Publication number: US2746395A
Application number: US260825A
Authority: US
Inventors: Paul G Carpenter
Original assignee: Phillips Petroleum Co
Current assignee: Phillips Petroleum Co
Priority date: 1951-12-10
Filing date: 1951-12-10
Publication date: 1956-05-22
Anticipated expiration: 1973-05-22

Description

May 22, 1956 P. G. CARPENTER GAS LIFT SYSTEM Filed Dec. 10, 1951 E LECTROMAGNET FIG. 3

MAGNETIC MATEKKAL 0R +PERMANENT MAGNET F/G. Z

INVENTOR. P.G. CARPENTER PERMANENT MAGNET F/ MAGNETIC MATERIAL 0R GAS LIFT SYSTEM Paul G. Carpenter, Bartlesville, kla., assignor to Phillips Petroleum Company, a corporation of Delaware Application December 10, 1951, Serial No. 260,825

' 12 Claims. (Cl. 103-233) This invention relates to producing oil from wells by a gas lift system. In one specific aspect, it relates to a system wherein any desired one of a pluralityof gas lift valves is selected and operated'as desired.

Gas lift devices areyparticularly advantageous in producing wells where there is a high level of oil between the T nitedStates Patent 'ice Figure 4 is a sectional view of a modification of the invention.

Referring now to the drawings in detail, and particular the casing, through one of a pluralityof openings 16 in Assuming that there is ahigh fluid level in the space between the-tubing and casing of a well, and that a series of gas lift valves is disposed along the tubing, gas is admitted to the space between the tubing and casing until the fluid levelfalls below the first gaslift valve. There upon, this valve is opened and gas flows therethrough into the tubing, thereby aerating the oil and causing it to rise to the surface. As the oil level between the easing and tubing drops below the second valve in the series, the uppermost valve is closed and the second valve is opened, operation being continued in this manner with one valve in the system open and the others closed. In

a second important method of operating, when the level drops below a valve, such valve is opened and the one above it is gradually closed in a stepwise fashion. Other methods of operation involve the opening and closing of any one or more of the gas lift valves depending upon the conditions under which the well is producing,

The system of this inventiompermits the selection and adjustment of any one valve so that, by successive adjustments, any desired ,scheme of operation can be ob tained. Further, it permit the size of each valve opening to be regulated as desired from the surface to maintain the optimum operating conditions.

It is an object of this invention to provide a readily controlled system .for selecting andoperating one of a plurality of gas lift valves in 'a pumping system for an oil well.

It is a further object to provide a magnetically operated system for reliably controlling a plurality of gas lift a valves. s

It is a still further object to provide a system which is simple in construction, and which utilizes a minimum number of parts.

Various other objects, advantages and features of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

Figure l is a vertical sectional view of the gas lift system of this invention.

Figure 2 is an enlarged sectional view of one'of the valve units of Figure l; i v

Figure 3 is a sectional view taken along the lines 33 of-Figure 2, looking in the direction of the arrows; and

the tubing and, thence, upwardly through the well whence it is dischanged from'the top portion 17 of the tubing.

-At the top of the well, the interspace between the tubing and casingis sealed by a cap 18, and fluid under pressure is'introduced into the interspace througha conduit 19.

A series of gas lift valves 20a to 202, inclusive, is spaced vertically along the tubing. In the example shown, there are five such valves but it will be understood that more or less can be used, as desired, depending upon the pressure conditions of the reservoir, the depth of the well, and various other factors well. known to those skilled in the art. Each valve, when open, admits fluid under pressure from the annulus or interspace 21 between casing 11 and tubing 12 to the interior of the tubing. The controlled fiow of gas thereby admitted to the tubing decreases the specific gravity of the oil passing upwardly therethrough and causes an upward flow of oil through the-tubing in a well understood manner. .In order to properly control the gas lift operation, it should be pos sible for any valve 20 to be selected and operated at any desired time. Further, it is highly desirable that the size of the valve opening be controllable so as to permit a selection of any of several desired orifice sizes, and thereby the selection of a properly regulated amount of gas to be fed to the tubing from the annulus 21. It is a major purpose of this invention to provide a reliable and effective means for controlling the selection and operation of the valves 20 in the manner just described.

To this end, each valve unit 20 is provided with a passage 22 extending from an opening 23 at the exterior of the tubing to an opening 24 from which the fluid is'admitted to the tubing. A valve seat 25 is formed. in the passage 22 and a valve head 26 cooperates with the valve seat 25 to open and close the passage 22,,the position of the valve head also being adjustable to provide several different orifice sizes, thereby to permitregulation of the amount of gas admitted to the tubing. Valve head 26 is carried by a stem 27 which is mounted for vertical move ment in a suitable passage 28 formed in an enlarged portion 29 of the tubing 12. A spring 30 urges the valve head into engagement with the valve seat.

In accordance with the invention, stem 27 carries a set of gear teeth 31 which mesh with teeth upon a gear wheel 32 suitable journaled in the enlarged portion 29 of the tubing.

Gear 32 is provided with a flat toothless portion33 and it is secured to and rotatable with a ratchet wheel 34 also mounted within the enlarged portion 29. Cooperating with ratchet wheel 34 isa pawl 35 which is movable radially in a passage 36 formed in the enlarged portion 29, the pawl having a generally cylindrical member 37 of magnetic material secured to the inner end thereof. The

member 37 is urged radially outward by a suitable spring, not shown. The inner end of the passage 36 is sealedby' a non-magnetic member 38.

Control of the opening and closing of the respective valves is elfectedby a valve-actuating assembly 40.which can be raised and lowered in the'tubing 12 by a cable 41. Referring to Figure 1, it will be noted that the cable 41 extends through a sealing device 42 at the top of the tubing and passes over a pulley 43 to-a Windlass 44. -In' one embodiment of the invention, the cable 41 incorporates a pair of electrical conductors, connection to which is made .by

brushes

45, 46 cooperating with suitable slip rings carried by the rotatable portion of the Windlass 44. Current is supplied, in this embodiment, to the cable conductors by a battery or other current source 47 controlled by a switch 48'.

Referring again to Figure 2, it will be noted that the assembly 40 includes a fixture 50 towhich the cable 41 is attached and a plurality of radial arms 51 extend from the fixture toward the tubing. Formed integrally with each arm 51 is a sector 52 of magnetic material and the sectors 52 form a ring of slightly less diameter than the interior of the tubingf'Each sector 52 carries an elongated vertically extending weight 52a to-facilitate lowering of the assembly through the tubing. The cable conductors are connected toa coil 5-3 having four sections 53a to 5355, inclusive, wound upon the respective arms 'SI. The arms 51 and sectors 52 are formedfrom magnetic material so that, when current is'fed to the coil 53, the structure acts as a powerful electromagnet.

In the operation of the system, the assembly 40 is lowered to'a position adjacent the valve which it is desired tooperate. In this position, one of the sectors is positioned closely adjacent the magnetic member 37 of the selected valve whatever the rotary'position of the assembly in thetubing may be. Thereupon, pulses of current are fed to the coil 53 by closure of switch 48. Each energization of the coil thereby eiiected causes the electromagnet to attract the member 37 with the result that the ratchet wheel 34 is advanced one step. Asv a result, a slight movement is imparted to gear wheel 32" p which moves the. stem 27': in an upward direction so as to partially open the valve 26. Continued applications 7 of current to the electromagnet cause the valve to be. gradually opened until the flat portion 33 of gear wheel 32; moves into proximity with thegear teeth 31. At this time, gear wheel 32 is no longer in mesh with gear teeth 31 so that the valve is closed by spring 39 and remains closed during -further actuations of the electromagnet until the teeth of gear wheel 32 again. move into position to engage the teeth 31.. Thus, by controlling the number of pulses fed to the electromagnet 53, the opening of. the valve to any desired position is obtained, as: is the closure of the valve. It'will be evident that the assembly can be moved adjacent any desired valve 20 which it. is desired to operate and the valve can be opened to any desired extent or closed to obtain the proper flow characteristics inthe gas lift system. A cam arrangement can be used instead of the rack and pinion, if desired.

Alternatively, the. electromagnet can be continuouslyenergized. and the assembly moved upwardly and down ward'ly between a position above the valve unit and a position below the valve unit. Each time the sectors 52 pass adjacent the magnetic member 37' the ratchet wheel 34 is advanced one step and. the valve. is operated in the manner already explained.

In another embodiment of the invention, asillustrated in; Figure 4,..the coil. 53 is eliminated and thesectors. 52 are combined so as to form an annular permanent magnet. When this annular permanent magnet passesadjacent a magnetic member 37, the. ratchet wheel 34' is advanced one step and the valve is operated in the manner previously noted. In this embodiment, it is desirable that. several teeth be eliminated from gear wheel 32 to. permit the assembly to be; moved past several valve. stations Without causing actuation of the valves as the assembly passes by. Thus, while the flat surface 33 of gear wheel 32 is positioned adjacent gear teeth 31 these is a period during which several stepwise movements ofratchet wheel- ,3 produce no actuation of. the valve, Alternatively, member 36 can be a permanent magnea and sectors 52 can be formed from magnetic material.

it will be evident that l have achieved the objects of my invent on n providing a y tem f ga ttal es h ein our e r d a v can e se ct d a i he closed or opened to any desired extent in'a prompt and etficacious manner. If desired, a plurality of electromagnets can be carried by a single supporting assembly for simultaneous operation of a plurality of valves. The system utilizes a minimum of parts and the assembly 40 is constructed so that it does not interfere appreciably with the fiow of the aerated oil through the tubing. When the operation of the Well is stabilized, one setting of the valves is maintained for a long period and, under such conditions, the assembly 40 and cable can be removed from the well until it is again necessary or desirable to change the operating conditions.

While the invention has been described in connection I with present, preferred embodiments thereof, it is to be understood that this description is illustrative only and is not intended to limit the invention.

I claim:

1. In combination, tubing suspended in a well, a series of vertically spaced valve units mounted, along said tubing,

each valve unit inclndinga valve having an actuating member formed from magnetic material, a valve actuating assembly, means for lowering said assembly into said well, said assembly having an actuating member of magnetic material, one of (a) said actuating members on said assembly and (b said actuating members on said valves taken collectively being magnetized whereby a magnetic attraction is set up between said members to actuate one of said valves each time said assembly passes adjacent a valve unit- 2.1.. In combination, tubing suspended in a well, a series of valve units vertically spaced along the exterior of said tubing, each valve. unitv including a valve having an actuating; member of magnetic material, an assembly including a weight, a Cable iOr lowering said assembly into the tubing, said assembly having a member of magnetic mate rial adapted to pass adjacent the respective valve actuating members as. the assembly is raised and lowered in the tubing, one of (a) said actuating members on said assembly and (b) said actuating members on said valves taken collectively being magnetized, a magnetic attraction thereby being established between said members when the assembly isadjacent a valve unit so as to actuate the valve thereof.

3 In combination, tubing suspended in a well, a series of valve units vertically spaced along the exterior of said tubing, each valve unit including a valve having an actuating member of magnetic material, an. assembly including a weight, a cable for lowering said assembly into the tubing, said assembly including an annular member of magnetic material at slightly less diameter than that of the tubing which passes, adjacent the respective valve actuating members as the assembly is raised and lowered in the tubing, one of (a), said actuating members on said assembly and (b) said actuating members on said valves taken collectively being magnetized, a magnetic attraction thereby beingestablished in any rotary position of the assembly as it passes adjacent a valve unit so as to actuate the valve of such unit.

4. The combination of claim 3 wherein the member of magnetic material forming a part of said assembly is a permanent magnet.

5. The combination of claim 3 wherein the member of magnetic. material forming a part of said assembly is an electromagnet.

6. In combination, tubing suspended in a well, a series of valve units vertically spaced along the exterior of said tubing, each valve unit including a passage leading from the exterior to the interior of the tubing, a valve seat in said passage, a valve head cooperating with said seat to open and close said passage, a spring urging said valve head to closed position, said valve head carrying a gear, a second gear carried by the tubing and meshing with the gear on said valve. head). said second gear having .a flat toothless portion, a ratchet wheel fixed to and rotatable with said second gear, a pawl. for advancing said ratchet in a stepwise manner, said. pawl having secured thereto a member of magnetic material positioned adjacent the assembly having an element of magnetic material adapted to pass adjacent the respectivevalve actuating members as the assembly is raised and lowered in the tubing, one or" (a) said elements, and (b) said members of magnetic material, taken collectively, being magnetized, a magnetic 1 'attractionthereby being establishedbetween said element and one of said members when the assembly is adjacent a valve unit so as to actuate the valve thereof.

7. In combination, tubing suspended in a well, a series of valve units vertically spaced-along the exterior of said tubing, each valve unit including a passage leading from the exterior to the interior ofthe tubing, a valve seat in said passage, a valve head'cooperating with said seat to open and close said passage, a spring urging said valve head to closed position, said valve head carrying a gear,

a second gear carried by the tubing and meshing with the gear on said valve head, said second gear having a fiat toothless portion, a ratchet wheel fixed to and rotatable with said second gear, a pawl for advancing said ratchet in astepwise manner, said pawl having secured thereto a member of magnetic. material positioned adjacent the interior edge of the tubing, an assembly, a cable for lowering said assembly into the tubing, said assembly including a ring-shaped permanent magnet of slightly less diameter than the interior-of said tubing, a pluralityof arcuate, longitudinally-extending weights spaced around the circumference of said permanent magnet, and cableattaching means extending radially from the center of. said assembly to said permanent magnet whereby, as the assembly is raised and lowered in the tubing, a magnetic attraction isestablished between said permanent'magnet and the magnetic members secured to the pawls of the respective valves so that each ratchet is advanced one step as the permanent magnet passes adjacent thereto,

such stepwise actuation causing the valve -to move toward open position in a stepwise manner and to close and remain closed when the flat portion of said second gear is adjacent the gear carried by the valve head.

8. In combination, tubing suspended in a well, a series "of valve units vertically spaced along the exterior of said tubing, each valve unit including a passage leading from the exterior to the interior of thetubing, a valve seat in said" passage, 21 valve head cooperating with said seat to open and close said passage,'a spring urging said valve head to closed position, said valve head carrying a gear,

a second gear carried by the tubing and meshing with the gear on said'valve head, said second-gear having a flat toothless portion, a ratchet .wheel fixed to and rotatable with said second gear, a pawl for advancing said ratchet in a stepwise manner, said pawl having secured thereto a member of magnetic material positioned adjacent the interior edge of the tubing, an assembly, a cable for lowering said assembly into the tubing, said assembly having a plurality of radially-extending arms of magnetic material, an arcuate sector at the end of each arm so tromagnetic held to be established between said sectors and the magnetic actuating member of a valve when the assembly is positioned adjacent a valve unit, successive applications of current to said coils thereby producing a stepwise movement of the ratchet wheel of such valve unit.

9. In combination, tubing suspended in a Well, a series of valve units vertically spaced along the exterior of said tubing, each valve unit including a passage leading from the exterior to the interior of said tubing, a valve seat formed in said passage, a valve head cooperating with said valve seat, a spring urging said head into engagement with said seat, a radial passage formed in said tubing and communicating with the interior thereof, a member of magnetic material mounted for radial movement in said passage, mechanism responsive to said magnetic member to. open said valve in a stepwise manner responsive to successive radial movements of said magnetic member to pass adjacent the respective valve actuating members as the assemblyis raised and lowered in the tubing, one of (a) said element, and (b) said members of magnetic material, taken collectively, being m-agnetiz'ed,;a magnetic attraction thereby being established between said element and one of said members when the assembly is adjacent a valve unit so as to actuate the valve thereof.

10. The combination of claim 9 wherein themember of magnetic material carried by said'assembly is an annular permanent magnet of slightly less diameter than said tubing. I i

11. The combination of claim 9 wherein the member of magnetic material carried by said assembly is an electromagnet.

12. In combination, tubing suspended in a well, a valve unit mounted on said tubing below the surface, said valve unit including a valve having an actuating member formed from magnetic material, a valve actuating assembly,

means for lowering said assembly into said well, said 2,278,552 Crickmer r Apr. 7,1942

2,307,171 Tutton JanfS, 1943 t

Claims

1. IN COMBINATION, TUBING SUSPENDED IN A WELL, A SERIES OF VERTICALLY VALVE UNITS MOUNTED ALONG SAID TUBING, EACH VALVE UNIT INCLUDING A VALVE HAVING AN ACTUATING MEMBER FORMED FROM MAGNETIC MATERIAL, A VALVE ACTUATING ASSEBLY, MEANS FOR LOWERING SAID ASSEMBLY INTO SAID WELL, SAID ASSEMBLY HAVING AN ACTUATING MEMBER OF MAGNETIC MATERIAL, ONE OF (A) SAID ACTUATING MEMBERS ON SAID ASSEMBLY AND (B) SAID ACTUATING MEMBERS ON SAID VALVES TAKEN COLLECTIVELY BEING MAGNETIZED WHEREBY A MAGNETIC ATTRACTION IS SET UP BETWEEN SAID MEMBERS TO ACTUATE ONE OF SAID VALVES EACH TIME SAID ASSEMBLY PASSES ADJACENT A VALVE UNIT.