US3375846A

US3375846A - Gas lift valve

Info

Publication number: US3375846A
Application number: US325716A
Authority: US
Inventors: Carlos R Canalizo
Original assignee: Otis Engineering Corp
Current assignee: Otis Engineering Corp
Priority date: 1963-11-22
Filing date: 1963-11-22
Publication date: 1968-04-02
Anticipated expiration: 1985-04-02

Description

pr 2,1968 c. R. CANALIZO 3,375,846

GAS LIFT VALVE Filed Nov. 22, 1963 FIG. 3

INVENTOR. CARLOS R. CANALIZO BYMWLW FIG. 2 fi-M United States Patent 3,375,846 GAS LIFT VALVE Carlos R. Canalizo, Dallas, Tex., assignor to Otis Engineering Corporation, Dallas, Tex., a corporation of Delaware Continuation-impart of application Ser. No. 277,064, Apr. 9, 1963. This application Nov. 22, 1963, Ser. No. 325,716

17 Claims. (Cl. 137-155) This invention relates to well tools and more particularly to well tools for removing fluids from the bores of wells by gas pressure, such as air or gas lift valves.

This application is a continuation-in-part of my copending application, Ser. No. 277,064, filed Apr. 9, 1963, now abandoned, which latter application was a division of my co-pending application, Ser. No. 38,342, filed June 23, 1960, now Patent No. 3,130,793.

An object of the invention is to provide a new and improved well tool for removing the liquids produced by wells through an inner well tubing disposed in a casing of the well wherein gas from the annular flow passage between the well casing and the inner well tubing provides the power for transporting the liquids to the surface through the inner well tubing.

Another object is to provide a well tool for automatically removing liquid from the bore of a well which includes a valve which opens intermittently to permit flow of the gas from the annular flow passage between the Well casing and an inner well tubing into the well tubing to transport liquids present in the well tubing above the valve to the surface.

Still another object is to provide a well tool for use in wells having a casing and an inner well tubing telescoped therein which includes a valve providing communication between. the interior of the well tubing and the annular space between the casing and the well tubing and which is responsive only to the pressure within the tubing above the valve to permit flow of fluid from the annular space into the tubing when the pressure within the tubing exceeds a predetermined value.

A further object is to provide a well tool for use in wells having a casing and an inner tubing telescoped therein which includes a valve affording communication between the interior of the tubing and the annular space between the casing and the inner tubing which opens to permit flow of fluid from the well casing into the inner tubing when the pressure within the tubing rises above a predetermined value without regard to the value of the pressure in the annular space between the well casing and the inner tubing and which closes when the pressure within the tubing decreases to substantially the same predetermined value at which the valve opens.

Still another object is to provide a new and improved gas lift valve for automatically removing liquid from the bore of a well which opens intermittently to permit flow of gas introduced into the annular flow passage between the well casing and an inner well tubing into the well tubing to transport liquids present in the well tubing above the valve to the surface. It is a further particular object of the invention to provide an improved gas lift valve which will open to admit gas into the tubing from the well bore or the annular space between the well casing and the tubing in a continuous regulated flow to aerate the column of fluid in the tubing and lift the same from the well, and wherein the valve is not affected by the casing pressure but opens in response to predetermined flow conditions within. the tubing string to provide a continuous regulated flow of lifting gas at high efficiency thereby using a minimum volume of gas to effect continuous flow from the well.

Still another object of the invention is to provide a gas lift valve of the character described for metering the flow of gas into the tubing which is provided with resilient means for controlling actuation of the valve and means for preventing application of excessive fluid pressure to such resilient means.

Still another object of the invention is to provide a gas lift valve which is unaffected by casing pressure and is thus suitable for use in multiple string gas lift installations, wherein each string of the multiple strings of tubing conducts production from a separate formation to the surface and has present therein a flow condition differing from the flow conditions in the other strings of tubing; such gas lift valve being unaffected by easing pressure so long as the casing pressure is sufliciently high to exceed the fluid pressure within the tubing string, whereby said valve controls the injection of lifting fluid from the casing annulus into each of the several tubing strings to flow the fluids present in such tubing string to the: well, the gas lift valve being subject to control of its operations only by the fluid pressure conditions present in the tubing string in which the valve is installed.

Additional objects and advantages of the invention will be readily apparent from the reading of the following description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

FIGURE 1 is a vertical sectional view of a portion of a well flow conductor or tubing string having a well tool embodying the invention disposed therein for removing fluids from the well;

FIGURE 2 is an enlarged view, partly in elevation and partly in section, of the valve of FIGURE 1, showing the valve in closed position; and,

FIGURE 3 is a view similar to FIGURE 2 of the lower portion of the valve and showing the valve in open position.

Referring now particularly to FIGURES 1 through 3 of the drawings, a fluid operated gas lift valve 10 is shown to be removably installed in a housing or landing nipple 11 connected in a tubing string 12. The landing nipple shown is of the type generally referred to as the offset type, and includes a landing section or pocket 13 which is welded into an opening in the wall of a housing 14 by means of the welds 15 and is laterally offset from the axis of the housing whereby a flow passage is provided through the housing past said pocket of a size approximating the size of the bore of the tubing string. An eccentric fitting 16 is welded to the lower end of the housing and is connectable to the tubing section 12 below the housing, the eccentric bore of the fitting being aligned with the passage through the housing past the pocket. A similar eccentric fitting (not shown) is provided at the upper end of the housing and in alignment with the fitting 16 and the tubing string thereabove is connected thereto where-by a continuous, unobstructed and uninterrupted passage is provided through the tubing and the housing.

The landing section or pocket 13 has a. longitudinal bore 17 opening to the upper end of said landing nipple, and an internal annular locking grOOVe or recess 18 is formed in the upper end of the bore wall of the pocket for receiving the locking dog of the well device secured in said pocket, as will be more fully described hereinafter.

A plurality of ports 21 through the exterior wall of the landing nipple at a point spaced below the locking recess but above the lower end of the landing section provide a fluid passage between the exterior of the landing nipple and the interior of the pocket, and a discharge port 22 at the lower end of the pocket permits fluid flow therethrough between the interior of the lower end of the pocket and the interior of the landing nipple and the tubing string.

The gas lift valve is provided with a locking mandrel 23 which is threaded onto a screw threaded pin at the upper end of an adapter plug 24 which is threaded into and closes the upper end of an elongate tubular chamber member or tube 25 of the gas lift valve. The locking mandrel 23 includes an expansible and retractable latch means 26 of the character to engage in the locking recess of the pocket. An external annular flange 27 near the upper end of the locking mandrel is engageable with the upper end of the pocket to limit downward movement of the valve in the pocket and a fishing neck or gripping head 28 at the upper end of the locking mandrel is engageable by a suitable running or retrieving tool (not shown) for inserting the valve into or removing it from the pocket.

A packing sleeve 29 having a bore 29a therethrough is threaded into the lower end of the chamber 25 and the lower end of the bore 29a is enlarged and receives the threaded upper end of an elongate tubular valve body 30 having a bore 31 therethrough. A lateral inlet port 32. is provided in the wall of the body and a restricted inlet orifice insert 33 is threaded into an enlarged portion of the lateral bore in the body for controlling the entry of fluids into the bore of the body as will be hereinafter more fully described. A lower tubular sub or packing mandrel 34 is threaded into the lower end of the body, and a guide and flow cap 35 provided with a plurality of longitudinal flow ports 36 therethrough is threaded onto the lower end of the sub. The lower end of the cap is downwardly and inwardly beveled or tapered to provide a guide nose whereby the valve may readily be inserted into the pocket.

An upper packing section 37 shown to be made up of a plurality of sealing rings of the V-type, is disposed on the outer surface of the body of the packing mandrel 29 and is retained thereon between an upwardly facing annular shoulder 38 on the body and the lower end of the chamber 25. A lower packing section 39 also shown to be made up of a plurality of sealing rings of the V- type, is disposed on the lower portion of the lower sub or packing mandrel 34 and is retained thereon between a downwardly facing shoulder 40 on said sub and the up- .per end of the flow cap 35. The

packing sections

37 and 39 seal between the valve 10 and the bore wall of the landing nipple or pocket for directing fluid flow from the ports 21 of the landing section or pocket to the lateral flow port 32 of the gas lift valve.

A check valve 41 is disposed in the bore of the lower packing mandrel or lower sub 34 and includes a supporting thimble 42 having a plurality of radial longitudinally extending narrow slots 43 provided in its outer periphery to permit flow of fluids through the bore of the lower sub or packing mandrel to the outlet openings in the cap. The thimble engages downwardly facing shoulder 44 in the bore of the lower sub and a resilient elastomeric, rubber or synthetic rubber or the like, cup 45 is confined between the concave lower surface 46 of the thimble and an upstanding retaining pin or mandrel 47 carried by the cap and engaging the central recess or counterbore 45a in the downwardly facing cylindrical portion of the resilient cup. The lower end of the pin or mandrel is disposed in an axial counterbore 48 in the cap 35 and this pin may be threaded or have a press fit in said opening if desired to maintain the same in place in the cap. When the cap is screwed onto the lower end of the lower end of the lower sub, the pin or mandrel presses the central portion of the cup 45 firmly into the central portion of the concave underside of the thimble 42, whereby the cup is firmly held in place in the thimble and in position to engage the cylindrical bore wall of the enlarged lower portion 49 of the bore of the lower sub or mandrel 34. If desired, the external diameter of the resilient cup 45 may be slightly less than the diameter of the enlarged portion 49 of the bore of th lower sub whereby fluid pressure may pass in either direction past the resilient cup, but a slight volume of flow in a direction from the cap toward the bore of the sub or mandrel thereabove will immediately flex the lip 50 of the cup outwardly into sealing engagement with the bore wall of the lower mandrel or sub. In this manner, back-flow of fluids through the mandrel is prevented, but there may be fluid pressure communication between the longitudinal ports of the cap and the bore of the mandrel or sub above the check valve.

The lower sub of the valve has at the upper end of its bore an upwardly facing annular seat ring 48 which is preferably formed of tungsten carbide or other suitable 1 hard material welded, soldered or otherwise suitably secured in place in an enlarged annular recess 49 formed in the upper end of the sub. A valve head 50 is mounted in the valve housing or body 30 for limited longitudinal movement between the closed position illustrated in FIG- URE 2, wherein the hardened tip insert 51 on the lower end of the valve head member 50 engages the hardened seat ring insert 48 disposed in the upper end of the bore of the lower sub 34, and an upper open position wherein an facing stop shoulder 55 provided by an enlarged external annular flange 56 on an elongate stem or plunger 57 connected by screw threads at its lower end to the valve head 50 engages a downwardly facing internal annular shoulder 58 formed in the bore of the upper packing sleeve 49. The valve head 50 and the hardened tip 51 thereon are provided with an axial bore 52 which extends upwardly therethrough and communicates with a counterbore 53 formed in the lower portion of the stem or plunger 57. A lateral port 54 communicates the counterbore with the exterior of the reduced lower portion 59 of the plunger below the flange 56 and the bore of the packing mandrel 29, whereby fluid pressure from below the valve head 51 may pass upwardly through the

bores

52 and 53 and the port 54 to the bore of the packing sleeve or mandrel 29.

When the tip 51 of the valve head is in engagement with the seat 48, it will be apparent that fluid from the inlet ports 21 of the pocket 13 will flow inwardly into the bore 17 of the pocket and be confined between the

packing assemblies

37 and 39 and thus directed through the inlet orifice member 33 into the bore of the valve body 30 where it will be confined between the seat 48 and an internal annular seal ring 60 which is disposed in an internal annular groove in the body and engages the reduced lower external cylindrical portion 59 of the plunger 57 below the port 54. The bore of the valve body also has internal annular recesses above and below the seal means 66 and in these recesses are disposed felt wipers 62 which wipe or clean the external surface of the reduced portion 59 of the valve plunger as the valve moves between its open and closed positions to prevent access of dirt or foreign matter to the seal means whereby the life of the seal means is prolonged.

An elongate cylindrical corrugated bellows 65 has a cylindrical annular flange 66 at its lower end secured by welding, soldering or otherwise to the plunger 57 at a point spaced above the flange 56, and the upper portion of the plunger 57 is reduced in diameter as at 67 whereby the bellows 65 is disposed in the annular space between the packing sleeve or mandrel 29 and the reduced portion 67 of the plunger. The upper end of the bellows has an external annular flange 68 which is welded or soldered or otherwise suitably secured to the upper end of the packing mandrel 29. The bellows thus provides a gastight fluid seal between the plunger 57 and the packing mandrel and is disposed about the reduced portion 67 of the plunger and spaced inwardly of the internal cylindrical surface of the mandrel, so that the bore of the mandrel opens downwardly and outwardly of the bellows to communicate with the annular space between the enlarged lower portion of the bore 61 of the packing mandrel and the reduced lower portion 59 of the plunger and thus communicates likewise with the lateral port 54 and the flow passage 52 through the valve 50 and the valve head 51.

An O-ring 69 is disposed in an external annular groove in the mandrel between the mandrel and the lower end of the bore of the tube of the valve above the packing assembly 37. Similarly, a lower seal ring 70 is disposed in an external annular groove in the valve body and seals between the valve body and the lower end of the bore of the packing mandrel. An O-ring 71 is disposed in an external annular groove in the lower sub or packing mandrel 34 and seals between the sub and the internal cylindrical surface of the lower end of the bore of the valve body. Thus, the various sections of the gas lift valve are suitably sealed against the passage of fluids therebetween from the exterior to the interior thereof.

The external annular flange 56 of the plunger 57 is provided with an external annular recess below the seat or shoulder 55 thereon and an O-ring or other suitable seal ring 64 is disposed in the groove and is adapted to engage such seal against the internal annular seal surface 63 in the bore of the mandrel 29 below the stop shoulder 58 when the valve is in its upper open position, whereby the bellows thereabove is protected from any excessive pressures from interiorly of the tubing passing upwardly through the valve passage 52 and the counterbore 53 and port 54 in the plunger 57. Also, when the valve head 50 is moved to the open position shown in FIGURE 3, gas pressure from exteriorly of the tubing entering through the ports 21 and the restricted orifice member 33 will be prevented from passing upwardly through the passage 52 of the valve and the counterbore 53, and port 54 in the plunger to act on the bellows to tend to rupture the same. It will be seen that the engagement of the upwardly facing shoulder 55 on the plunger with the downwardly facing shoulder 58 in the mandrel likewise prevents excessive movement of the plunger and thereby also limits the compressive force applied to the bellows 65 to prevent rupture thereof due to compressive movement, while the seal member 62 prevents excessive fluid pressure from acting on the bellows to tend to rupture the same or otherwise deform or damage it.

When the valve is in the closed position shown in FIG- URE 2, the pressure within the bore of the lower mandrel or sub 34 may pass upwardly through the passage 52 in the valve head and the counterbore 53 and port 54 in the plunger and act on the bellows to exert a fluid pressure force thereon which tends to move the plunger and the valve head carried thereby upwardly from the closed position shown in FIGURE 2 toward the open position shown in FIGURE 3 wherein the valve tip 51 does not engage the seat 48. When the valve is moved to the open position, it is obvious that lifting fluid or gas entering through the orifice member 33 may pass downwardly between the valve tip 51 and the seat 48 and through the bore of the lower sub and the slots 43 in the thirnble 42 past the sealing cup 45 and outwardly through the openings 36 in the cap to aerate and lift oil or other fluids present in the bore of the tubing string.

The valve stem or plunger, 57 is provided at its upper end with an annular ring guide 80 telescoped on the re duced upper end tip portion 81 of the plunger or stem. The ring guide is somewhat smaller in diameter than the internal diameter of the bore of the upper portion of the tube 25 so that it permits free longitudinal movement of the valve plunger or stem but tends to prevent any substantial lateral movement thereof, when such lateral movements exceed predetermined limits, by engaging the internal surface of the tube 25. The valve stem or plunger 57 is biased downwardly toward the lower closed position by a helical coil spring 83 which is disposed within the tube 25 and has its lower end bearing against or supported on the ring guide 80 and its upper end engaging or bearing against an upper adjusting screw 84 threaded into the internally threaded upper end 87 of the tube 25. The adjusting screw 84 is locked against movement from any adjusted position in the tube by means of a suitable detent means thereon which may comprise a nylon ball or pellet 85 which is disposed in an external recess or opening in the screw and frictionally engages the internal threads 87 of the housing to prevent undesired rotation of the screw in the housing. The adjusting screw is provided at its upper end with a transverse slot or aperture 86 by means of which it may be adjusted in position in the threaded bore 87 in the upper end of the housing or tube. A longitudinal axial bore 88 is formed in the adjusting screw and provides for equilization of fluid pressures above and below the adjusting screw within the bore of the tube during the longitudinal movement of the valve, since the bellows 65, the plunger 66 and the tube 25 together with the adapter plug 24 form a closed chamber 89 having no vent. This chamber, if desired, may be charged with compressible gas to any desired pressure, either greater or less than atmospheric pressure. If desired, a fitting 90 may be provided in the wall of the tube 25 through which gas may be introduced into the chamber 89 as desired.

When the pressure in the bore of the housing and in the bore of the tubing string acting upwardly through the inlet opening 22 in the pocket and the passages 36 in the cap 35 past the check valve cup 45 rises to such a value that its force on the effective area of the bellows 65 overcomes the force of the spring 83 and the pressure of the gas confined in the closed chamber 89, the valve head 50 is moved toward its open position. As soon as the valve tip 51 moves away from the seat 48, the fluid pressure acting through the orifice member 33, which is greater than the pressure in the bore of the mandrel or sub below the seat 48, enters the flow passage 52 of the valve head and passes upwardly therethrough and outwardly through the lateral port 54 and acts against the full eflective area of the bellows 65 to force the valve plunger or stem 67upwardly moving the valve head to its open position, further compressing the spring 83. As the valve moves to its open position, the O-ring or seal member 64 engages the internal seal surface 63 of the packing mandrel 29 and thus protects the bellows against the action of the full pressure thereon and against collapse due to excessive pressure by sealing the annular chamber 61. between the plunger 57 and the seal surface below the shoulder 58. The valve is stopped against further upward movement when the external annular shoulder 55 of the plunger engages the downwardly facing stop shoulder 58 in the packing mandrel. With the valve thus open, fluids may flow through the orifice member 33 into the body and down wardly through the lower sub and past the check valve 45 into the well tubing.

As the well fluids rise in the tubing past the gas lift valve, gas continuously flows through the gas lift valve to form bubbles in the flowing column, the pressure of the gas assuming the same pressure as that of the. following column at that point. The pressure will va y slightly, so that as the pressure decreases, the valve tip will move downwardly relative to the seat 48 and meter the admission of gas into the well fluids in the tubing to thus reduce the amount of gas being injected into the column. If the pressure of the fluid column in the tubing increases slightly the valve head will open slightly to let additional gas into the tubing, and the valve tip 51 will move upwardly away from the seat to increase the annular orifice therebetween and admit additional gas into the tubing to further aerate the column.

Due to the elongate tapered external surface 51a of the tip 51 of the valve head being always disposed in the bore of the seat 48, the orifice therebetween will always be a small annular orifice and there will be a metering of the gaseous fluid admitted into the well tubing.

The bore diameter of the intake port or orifice 33 is large as compared to the annular orifice provided by the valve head 50 and the seat 48 so that the orifice 33 does not act as a restriction which would produce a drop in pressure t-hereacross but is merely a replaceable orifice used to limit the maximum gas flow into the well tubing string through the gas lift valve.

When the column of fluid in the tubing string has been sufliciently lightened or aerated, the pressure of the fluids in the tubing acting on the valve head 50 decreases and the valve head is moved toward the seat to close off flow, and when the pressure decreases to substantially the same predetermined value as that impressed upon the valve by means of the spring and the fluid confined in the chamber 89, the valve plunger or stem is moved downwardly and the valve head is moved into engagement with the seat 48 to close off flow of fluids through the seat from the orifice inlet 33. When the valve is in its closed position, the fluid pressure across the orifice 33 equalizes, but this pressure, while being greater than the pressure within the bore of the lower sub, does not tend to move the valve to the open position, since the area of the valve seat engaged by the valve tip 51 is substantially equal to the area sealed off by the seal means 60 in the body engaging the plunger or stem 57. The valve thus opens and closes at substantially the same pressure, and this pressure may be adjusted to any desired value by varying the compression of the spring 83 by rotation of the adjusting screw 84 and by varying the pressure of the gas confined in the chamber 89.

In use, the gas lift valve 10 is disposed in the pocket 20 with the ports in the cap at the lower end of the valve in communication with the bore of the housing and the tubing thereabove and therebelow through the opening 22 at the lower end of the pocket. The lower end of the well tubing is open and ermits flow of well fluids produced by the well upwardly through the tubing, and the pressure of the fluids in the tubing act through the passage 22 and the openings 36 in the cap past the check valve 45 which is in its normal non-sealing position, and thus pass upwardly through the bore of the lower sub and the bore 52 of the valve 53 of the plunger and the lateral port 54 into the chamber 61 where the pressure acts on the bellows 65.

The orifice member 33 provides communication between the tubing-casing annulus exteriorly of the landing nipple 11 and the interior of the pocket 13, and as well fluids are produced by the well and flow upwardly in the well tubing and within the landing nipple, the pressure exerted on the bellows 65 increases to move the plunger 57 upwardly and lift the valve head t) and the tip 51 thereof upwardly off the seat 48 permitting fluids to flow inwardly through the orifice 33 into the bore of the body 30 and downwardly therefrom through the bore of the sub 34 past the check valve 45 and outwardly through the openings 36 and the cap 35 to the bore of the landing nipple through the passage 22 to aerate and lift the fluids present in the tubing. The column of fluids in the tubing above the orificed inlet member 33 of the gas lift valve increases until the same attains a predetermined height and produces a hydrostatic pressure which exerts a force of predetermined value in the manner described acting on the bellows 65 against the force of the spring 83 and the charge of gas, if any, in the chamber 89. When the valve head 50 moves upwardly to the open position, the gas from the annulus exteriorly of the landing nipple passing inwardly through the inlets 21 and the orifice 33 flows downwardly past the valve head 50 and into the bore of the tubing to lift the column of fluid therein. When the valve head 50 is moved to its open position, substantially the full pressure of gas entering through the openings 21 will pass into the gas lift valve and act on the bellows, tending to move the same upwardly to ward its fully open position, whereupon the seal member 64 engages the seal surface 63 to prevent further application of pressure to the bellows and the engagement of the shoulder 55 with the shoulder 58 limits upward movement of 'the plunger to prevent mechanical compressive damage to the bellows.

Due to the inertia of the column or slug of liquid in the tubing above the port 22 of the pocket, the flow of gas through the gas lift valve is slow at first but increases as the upward movement of the liquid column through the tubing is accelerated. As the gas from the exterior of the landing nipple enters the tubing at an increasing rate to aerate and accelerate flow, the column of liquid is lightened in weight and the head pressure of the column acting on the valve is reduced, whereby a drop in pressure is created across the annular orifice between the tip 51 of the valve and 'the seat 48. As a result, the valve head 5% is moved downwardly by the force of the spring 83 and the pressure of the charge of gas, if any, in the chamber 89 acting downwardly on the bellows 65, whereupon the tip 51 is moved downwardly in the bore of the seat 48 to reduce the size of the annular orifice therebetween to restrict the flow of gaseous fluid therethrough and thereby reduce the rate of entry of gas into the column of liquid in the tubing. The admission of gas through the valve 10 is thus metered by the valve head 50 as it moves toward and away from the seat 48 and a continuous flow of gaseous lifting fluid is admitted through the seat into the bore of the landing nipple to lift the well liquids present therein, resulting in a controlled continuous metered lifting of the fluids by means of the valve.

As the well fluids are lifted through the tubing, the weight of the column of liquid therein will be reduced until ultimately the valve head 50 will be moved downwardly until the tip 51 thereon engages the seat 48 to shut off flow of fluids through the annular orifice therebetween, whereupon further admission of gas through the inlet orifice 33 is prohibited until the column of liquid present in the bore of the tubing rises to such an extent that the valve tip will be lifted off the seat 48 in the manner previously described. It will thus be seen that the valve is dependent upon fluid conditions present in the bore of the tubing for control of the operation of such valve.

It will also be seen that the valve may be used in offset pockets to control admission of lifting gas to an inner tubing, or may be mounted in the usual manner on the exterior of the tubing; and that the valve functions to provide for a continuous metered flow of lifting fluid through the valve into the bore of the tubing to lift the column of fluid therein.

It will also be seen that the operation of the valve is independent of pressure conditions exteriorly of the well tubing, and that the valve opens only when the fluid pressure in the tubing attains a predetermined value at the discharge opening 22 of the pocket and the opening 36 of the valve assembly; and that, as a result, the valve is particularly adapted for use in multiple string, multiple zone well installations.

It will further be seen that due to the counter-balancing of the forces exerted by the fluid pressure entering the housing through the orifice member 33 and acting on the valve head 50 and the reduced lower portion 59 of the stem 57, the valve is opened and closed at substantially the same value of pressure occurring in the flow passage of the bore of the sub 34 therebelow.

It will also be seen that the valve may be used in wells producing both gases and fluids or liquids to cause the produced gases present in the well casing to transport the liquids produced by the well from the bottom of the well to the surface through the inner well tubing.

The foregoing description of the invention is explanatory only, and changes in the details of the construction illustrated may be made by those skilled in the art, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. A well tool including: a housing having a flow passage and a lateral aperture intermediate the ends of said housing communicating said flow passage with the exterior of the housing; a valve means comprising an elongate body longitudinally slidable in said housing, said housing having a valve seat engageable by said elongate body when said elongate body is moved in one direction to one'extreme longitudinal position in said housing; sealing means between said elongate body and said housing, said ,lateral aperture being disposed between said valve seat and said sealing means, said elongate body closing said flow passage 'to prevent flow of fluids from said aperture to said flow passage when said elongate body is in said one extreme longitudinal position; and means responsive to fluid pressure comprising a bellows having one end connected to said elongate body and another end connected to said housing to form a chamber in said housing between said housing and said bellows; said elongate body having a longitudinally extending internal flow passage formed therein communicating at one end with the flow passage of the housing and extending longitudi nally of said elongate body past said sealing means to the exterior of said elongate body at a point communicating With said chamber in the housing to conduct fluid pressure from the flow passage of said housing to said means responsive to fluid pressure for actuating said elongate body; said elongate body and said housing having coengagea'ble means for closing said chamber from said passageway of said elongate body when said elongate body moves to open position, said elongate body and said valve seat providing an annular flow passage therebetween smaller in area than the area of the lateral aperture of the housing controlling flow from said lateral aperture through said seat to the flow passage of the housing, whereby the elongate body of the valve means is movable in response to fluid pressure of the fluid in the flow passage of the housing.

2. A well tool including: a housing having afloW passage and a lateral aperture intermediate the ends of said housing communicating said flow passage with the exterior of said housing; valve means comprising an elongate body longitudinally slidable in said housing; a valve seat in the passage of said housing engageable by said elongate body when said elongate body is moved in one direction in said housing to one extreme closed position therein; sealing means between said elongate body and said housing, said lateral aperture being disposed between said valve seat and said sealing means, said elongate body closing said flow passage of said housing to prevent flow-of fluids from said aperture :through said flow passage and seat when said elongate body is in said one extreme longitudinal position relative to said housing; said elongate body having a flow passage therein communicating at one end with said flow passage of said housing adjacent said valve seat and extending past said sealing means to the passage of said housing therebeyond; fluid pressure responsive means operative'ly associated with said elongate body and said housing and exposed to the pressure from said flow passage of said elongate body for moving said elongate body from said one extreme position to an open opposite extreme position permitting flow of fluids between said aperture and said flow passage through said seat; the flow passage through said seat between said seat and said valve means being smaller in area than the area of the lateral aperture of the housing, whereby fluid pressure flowing through said lateral aperture has substantially no eflecton operation of the valve and the elongate body is movable between open and closed positions in response to fluid pressure of fluid in the flow passage of the valve seat; shutoif means .on said elongate body and said housing spaced longitudinally from each other when said elongate body is in said one extreme position to expose said fluid responsive means ,to the fluid pressure from the passage of said elongate body, and movable into engagement with each other when said elongate body is in said opposite extreme longitudinal position in said housing to shut oil? flow of fluid from said passage to said fluid responsive means to protect-the same against such pressure.

3. A well tool including: a housing having a flow passage and a lateral aperture intermediate the ends of said housing communicating said flow passage with the exter-ior of said housing; valve means longitudinally slidable in said housing; a valve seat in said housing passage and 1:0 engageable by said valve means when said valve means is moved in one direction in said housing to one extreme longitudinal closed position therein and with said valve means providing an annular flow passage therebetween (having a smaller area than the area of the lateral aperture one extreme longitudinal position and movable to an op posite extreme longitudinal position to open said passage and seat to flow from said aperture through said passage and seat; said valve means having an elongate flow-passage extending axially therethrough and communicating at one end With the chamber between the housing and the bellows and at its opposite end with said flow passage to said housing adjacent said seat whereby fluid pressure from said flow passage of said housing is in communication with said chamber and may pass through said valve means passage and to said chamber to act on said bellows to move said valve means to open position; the smaller annular passage through said valve seat between said valve seat and said valve means controlling flow of fluid through said housing passage from said lateral aperture of the housing, whereby fluid flowing through said lateral aperture has substantially no effect on operation of the valve and said valve means is actuated by the pressure of the fluids in the flow passage of the housing downstream of said valve seat; and seal means onsaid housing and said valve means spaced from each other when said valve means is in said one extreme longitudinal position and engageable when said valve means is in said opposite extreme longitudinal position to seal off the chamber between said rbellows and said housing from the fluid pressure entering said chamber from the outlet of the passage in the valve means to protect said bellows against action of said pressure,

4. A well tool including: a housing having a flow passage and a lateral aperture intermediate the ends of said housing communicating said flow passage with the exterior of said housing; valve means comprising an elongate body longitudinally slida-ble in said housing, said housing having a valve seat engaged by said elongate body when said elongated body is moved in one direction to one extreme longitudinal position in said housing to close off flow through said passage and seat and when moved in an opposite direction to an opposite extreme longitudinal open position in said housing providing with said valve seat and saidelongate body an annular restricted flow passage therethrough having a smaller cross-sectional area than the area of a lateral aperture of the housing; fluid pressure responsive means operatively associated with said housing and said elongate body for moving said elongate body from said one extreme closed position to an opposite extreme open position permitting fluid to flow through said aperture and said flow passage and said seat, said fluid pressure responsive means comprising an elongate cylindrical bellows having one end connected to said elongate member and another end connected to said housing to form a chamber between said housing and the exterior of said bellows; sealing means slidably sealing between said elongate body and said housing, said lateral aperture of said housing being disposed between said valve seat and said sealing means, said elongate body closing said seat to prevent flow of fluids from said aperture through said flow passage and seat when said elongate body is in said one extreme longitudinal position; said elongate valve means having an elongate flow passage formed therein communicating at one end with the flow passage of the housing adjacent the valve seat and extending at its opposite end past said sealing means and communicating with the chamber between said housing and the exterior of said bellows past such sealing means to expose said bellows to fluid pressure from said flow passage of said housing adjacent the seat for acting on said bellows to move said elongate valve body to said opposite extreme position; means biasing said elongate valve means toward said valve seat; the smaller annular passage through said valve seat between said valve seat and said valve means controlling flow of fluid through said housing passage from said lateral aperture of the housing, whereby fluid flowing through said lateral aperture has substantially no effect on operation of the valve and said valve means is actuated by the pressure of the fluids in the flow passage of the housing downstream of said valve seat; and shut-off means on said elongate valve body and said housing spaced from each other when said valve body is in said one extreme longitudinal position engaging said seat and engageable with each other when said elongate valve body is in said opposite extreme longitudinal position, said shut-off means being disposed between the passage of the valve member and the bellows to prevent fluid pressure from said passage acting on said bellows when said shut-off means are in engagement.

5. In a well tool of the character set forth in claim 4, biasing means in said body engaging said elongate valve body and biasing said elongate valve body toward said valve seat.

6. In a well tool of the character set forth in claim 4, adjustable stop means in said housing; and means biasing said elongate valve body toward said valve seat and comprising a helical coil spring confined in said housing and engaging said elongate body at one end at is opposite end engaging said adjustable stop means in said housing whereby the force applied by said spring to said valve body may be adjusted by adjustment of said stop means in said housing.

7. A well tool of the character set forth in claim 4 wherein the housing passage beyond said bellows on the side of said bellows opposite said seat is closed by a closure member to form a chamber in said housing between said housing and said bellows for receiving fluid under pressure therein, whereby fluid under pressure may be introduced into said chamber to act on said bellows to bias said elongate valve body toward said seat to close said seat.

8. A valve of the character set forth in claim 4 wherein the housing passage beyond said bellows on the side of said bellows opposite said seat is closed by a closure member to form a chamber in said housing between said housing and said bellows for receiving fluid pressure therein whereby fluid under pressure may be introduced into said chamber to act on said bellows to bias said elongate valve body toward said seat to close off flow through said seat; and resilient means is disposed in said housing operatively associated with said elongate valve body biasing said elongate valve body toward said valve seat and comprising a helical coil spring confined in said housing and engaging said elongate member at one end and at its opposite end engaging said closure member in said housing passage whereby the force applied by said spring to said valve body may be adjusted by adjustment of the position of said closure member in said housing.

9. A well tool including: an elongate valve housing having a flow passage therein open at one end exteriorly of the housing and closed at the opposite end of said housing; a lateral inlet opening intermediate the ends of said housing and communicating the exterior of said housing with the flow passage therein; a valve seat within the flow passage of said housing between said lateral aperture and the open outlet end of the flow passage; an elongate valve member movable longitudinally in the passage of the body between a first extreme longitudinal closed position in engagement with said seat and a second extreme longitudinal open position out of engagement with said seat, said valve member and said seat providing an annular restricted orifice therebetween having a smaller cross-sectional area than the area of the lateral aperture of the housing; seal means between said valve member and said housing in the flow passage and disposed in the housing on the side of said aperture opposite said seat whereby fluid pressure entering through the lateral aperture into said passage is directed toward said seat and is prevented from flowing in said passage between said valve member and said body other than to said seat; an elongate cylindrical fluid pressure responsive bellows surrounding said valve member and connected at one end to said housing and at the opposite end to said valve member and forming a chamber in said housing between said housing and said bellows on the opposite side of said seal means from said valve seat; said valve member having a longitudinal flow passage therein open at one end of said valve member and communicating with the flow passage of said body adjacent said seat and at its opposite end communicating laterally exteriorly of said valve member with said closed chamber between said seal means and said bellows whereby fluid pressure entering said passage from adjacent said seat is conducted to the chamber between said bellows and said housing above said seal means and said valve member is moved in response to pressure in said housing passage adjacent said seat; biasing means between the closed end of said body and said valve member biasing said valve member to closed position engaging said seat, fluid pressure from the passage of the body passing through the passageway of the valve member to the chamber between the housing and the bellows acting on said bellows to move said valve member to open position; the smaller annular passage through said valve seat between said valve seat and said means controlling flow of fluid through said housing passage from said lateral aperture of the housing, whereby fluid flowing through said lateral aperture has substantially no effect on operation of the valve and said valve means is actuated by the pressure of the fluids in the flow passage of the housing downstream of said valve seat; shut-off means on said housing and on said valve member coengageable When said valve means is moved to open position to shut off fluid pressure from said passage of said valve member to said chamber between said bellows and said housing to protect the bellows from such pressure; said shut-off means being moved to open position when said valve member is moved to said first extreme longitudinal closed position in engagement with said valve seat, whereby said bellows is acted upon by the fluid pressure from the passage of the valve housing to move said valve member to open position and to permit fluid pressure from said lateral inlet of said housing to enter said valve passage to coact with the pressure from beyond the seat to move said valve member to said second extreme position, said shutoff means protecting said bellows from such action of the fluid pressure when the valve is in such second extreme open position.

10. A well tool of the character set forth in claim 4, wherein the shut-off means includes: adjacent annular sealing and stop surfaces in said housing; an enlarged annular flange member on said valve member having an abutment shoulder engaging the stop surface in said housing when said valve member is moved to said other extreme longitudinal position to limit movement of said valve member in said housing; and annular sealing means on said flange engageable with the sealing surface of said housing for sealing therebetween to prevent fluid pressure passing said flange and said sealing and stop surfaces.

11. A device of the character set forth in claim 4, wherein said valve means includes: a valve head having an elongate tip extending through said annular seat and movable longitudinally toward and away from engagement with said seat to provide a variable annular orifice between said tip and said seat for metering flow of fluids 13 therethrough in response to the pressure of the fluids within the tubing string.

12. A device of the character set forth in claim 2 wherein said valve seat is: an annular seat and said valve means includes a valve head having an elongate tapered tip extending through said annular seat and movable longitudinally toward and away from engagement with said seat to provide an annular orifice between said tip and said seat for metering flow of fluids therethrough in response to the pressure of the fluids downstream of said seat, said valve head being carried by said elongate body and of suflicient length to remain disposed in said annular seat when said shut-01f means is engaged position.

13. A well too] including: a housing having a flow passage and a lateral aperture intermediate the ends of said housing and communicating said flow passage with the exterior of said housing; valve means longitudinally slidable in said housing; a valve seat in said housing engageable by said valve means when said valve means is moved in one direction in said housing to one extreme closed position; sealing means between said valve means and said housing spaced beyond the lateral aperture from said valve seat whereby said lateral aperture is disposed between said valve se-at and said sealing means; said valve means closing said flow passage to prevent flow of fluids from said aperture through said seat when said valve means is in said one extreme longitudinal closed position; means operatively associated with said valve means and said housing and exposed to fluid pressure conducted from downstream of said seat in said flow passage of said housing for moving said valve means in a direction opposite to said one direction from said one extreme longitudinal closed position when said fluid pressure in said passage increases to a predetermined value; said valve means including an annular seat and a valve head having an elongate tip extending through said annular seat and movable longitudinally toward engagement with and away from engagement withsaid seat to provide a variable annular orifice between said tip and said seat having a cross-sectional area smaller than the lateral aperture of said housing for metering flow of fluids through said housing from said lateral aperture to the flow passage beyond said valve seat; and sealing means on said valve means and said housing spaced from each other out of sealing engagement when said valve means is in said one extreme longitudinal closed position and engagebale when said valve means is is said other extreme longitudinal open position to seal ofl the pressure in said flow passage from said means responsive to fluid pressure for moving said valve means in said housing.

14. A well tool including: a housing having a flow passage with a discharge opening adjacent one end of said housing, sad housing having a lateral inlet aperture intermediate its ends communicating the exterior of said housing with the flow passage thereof at a point spaced from said discharge opening; an annular valve seat in said flow passage of said housing between said lateral aperture and said discharge opening; elongate valve means longitudinally slidable in said housing and having a per tion disposed within said valve seat and movable longitudinally in one direction relative thereto into a closed position in engagement with said seat and in the opposite direction to an open position out of engagement with said valve seat and providing an annular flow orifice therebetween smaller in area than said lateral aperture of said housing; sealing means in said housing between said valve means and said housing spaced beyond the lateral aperture from said valve seat, whereby said lateral aperture is disposed between said valve seat and said sealing means; a longitudinal internal flow conduit extending from a point adjacent the valve seat to a point in said housing spaced longitudinally beyond the sealing means in said housing;

pressure responsive means operatively associated with said elongate valve means and said housing for moving said valve means from c-losed to open positions in response to fluid pressure in said flow passage between said valve seat and said discharge opening in excess of a predetermined value; said internal flow conduit providing a flow passage for fluid from the flow passage of the valve housing between the valve seat and the discharge opening of said housing to the pressure responsive means for conducting fluid pressure from said flow passage of said housing to said pressure responsive means for moving said valve between closed and open positions in response to such fluid pressure; the annular flow orifice between said valve means and said valve seat being variable in size as the valve means is moved with respect to said seat for controlling flow from said lateral inlet aperture through said seat to the discharge opening of the housing, whereby fluid pressure entering the flow passage of the housing through the lateral aperture has substantially no effect on operation of the valve and the elongate valve member is movable in response to fluid pressure of the fluid in the flow passage of the housing downstream of said annular orifice.

15. A well tool of the character set forth in claim 14, wherein coengageable means are provided on the housing and the elongate valve means between said pressure responsive means and said flow passage from said valve seat to said pressure responsive means engageable when said valve means is in said open position to close off access of fluid pressure from said internal flow passage to said pressure responsive means.

16. A well tool of the character set forth in claim 14 wherein the longitudinal internal conduit extending from a point adjacent the valve seat to a point in said housing spaced longitudinally beyond the sealing means in said housing comprises a longitudinal conduit formed in said elongate movable valve means and extending from the end thereof adjacent the seat longitudinally of said valve means to a point spaced from said end beyond the sealing means in the housing between the valve means and the housing and opening from said elongate valve means to said pressure responsive means, whereby fluid pressure from the flow passage downstream of the end of said valve means adjacent the valve seat is conducted through said longitudinal conduit in said valve means to said pressure responsive means for acting on said pressure responsive means to move said valve means between closed and open positions.

17. A well tool of the character set forth in claim 16 wherein the portion of the elongate valve means longitudinally movable within the valve seat comprises an elongate tip tapering toward the end of said valve means and extending through the seat and having its larger portion movable longitudinally toward and away from engagement with said seat to provide said variable annular orifice between said tip and said seat for metering flow of fluids therethrough in response to the pressure of the fluids within the flow passage of the housing between the valve seat and the discharge opening thereof.

References Cited UNITED STATES PATENTS 2,250,464 7/1941 Boynton l37-155 2,688,553 2/1954 Howard 137-155 2,797,700 7/1957 McGowen 137155 2,815,764 12/1957 Bryan 137-155 2,904,305 9/ 1959 Novot'ny 251-322 X 2,982,226 5/1961 Peters l03-232 X 3,066,690 12/1962 Tausch 137-155 ALAN COHAN, Primary Examiner.

Claims

1. A WELL TOOL INCLUDING: A HOUSING HAVING A FLOW PASSAGE AND A LATERAL APERTURE INTERMEDIATE THE ENDS OF SAID HOUSING COMMUNICATING SAID FLOW PASSAGE WITH THE EXTERIOR OF THE HOUSING; A VALVE MEANS COMPRISING AN ELONGATE BODY LONGITUDINALLY SLIDABLE IN SAID HOUSING, SAID HOUSING HAVING A VALVE SEAT ENGAGEABLE BY SAID ELONGATE BODY WHEN SAID ELONGATE BODY IS MOVED IN ONE DIRECTION TO ONE EXTREME LONGITUDINAL POSITION IN SAID HOUSING; SEALING MEANS BETWEEN SAID ELONGATE BODY AND SAID HOUSING, SAID LATERAL APERTURE BEING DISPOSED BETWEEN SAID VALVE SEAT AND SAID SEALING MEANS, SAID ELONGATE BODY CLOSING SAID FLOW PASSAGE TO PREVENT FLOW OF FLUIDS FROM SAID APERTURE TO SAID FLOW PASSAGE WHEN SAID ELONGATE BODY IS IN SAID ONE EXTREME LONGITUDINAL POSITION; AND MEANS RESPONSIVE TO FLUID PRESSURE COMPRISING A BELLOWS HAVING ONE END CONNECTED TO SAID ELONGATE BODY AND ANOTHER END CONNECTED TO SAID HOUSING TO FORM A CHAMBER IN SAID HOUSING BETWEEN SAID HOUSING AND SAID BELLOWS; SAID ELONGATE BODY HAVING A LONGITUDINALLY EXTENDING INTERNAL FLOW PASSAGE FORMED THEREIN COMMUNICATING AT ONE END WITH THE FLOW PASSAGE OF THE HOUSING AND EXTENDING LONGITUDINALLY OF SAID ELONGATE BODY PAST SAID SEALING MEANS TO THE EXTERIOR OF SAID ELONGATE BODY AT A POINT COMMUNICATING WITH SAID CHAMBER IN THE HOUSING TO CONDUCT FLUID PRESSURE FROM THE FLOW PASSAGE OF SAID HOUSING TO SAID MEANS RESPONSIVE TO FLUID PRESSURE FOR ACTUATING SAID ELONGATE BODY; SAID ELONGATE BODY AND SAID HOUSING HAVING COENGAGEABLE MEANS FOR CLOSING SAID CHAMBER FROM SAID PASSAGEWAY OF SAID ELONGATE BODY WHEN SAID ELONGATE BODY MOVES TO OPEN POSITION, SAID ELONGATE BODY AND SAID VALVE SEAT PROVIDING AN ANNULAR FLOW PASSAGE THEREBETWEEN SMALLER IN AREA THAN THE AREA OF THE LATERAL APERTURE OF THE HOUSING CONTROLLING FLOW FROM SAID LATERAL APERTURE THROUGH SAID SEAT TO THE FLOW PASSAGE OF THE HOUSING, WHEREBY THE ELONGATE BODY OF THE VALVE MEANS IS MOVABLE IN RESPONSE TO FLUID PRESSURE OF THE FLUID IN THE FLOW PASSAGE OF THE HOUSING.