US2573110A - Well flow device - Google Patents

Description

Oct. 30, L ROBISQN WELL FLOW DEVICE Filed Aug. 15, 1945 ZZ ZC) @obi 5012 INVENTOR.

Patented Oct. 30, 1951 OFFICE WELL FLOW DEVICE Jay L. Robison, Dallas, Tex., assignor to Merla Tool Corporation, Dallas, Tex., a corporation of Texas Application August 13, 1945, Serial No. 610,571

9 Claims.

This invention relates to new and useful improvements in well flow devices.

One object of the invention is to provide an improved device for controlling the admission of a lifting fluid, such as gas, into a liquid column within a well tubing or conductor for lifting or raising the liquid within said well tubing or conductor to the surface, said device being particularly adapted for use as an intermitter to intermittently admit the lifting fluid at predetermined intervals in accoordance with well conditions.

An important object of the invention is to provide an improved well iow device wherein the operation of the main gas inlet valve is controlled by a pilot valve with the latter being actuated solelyT in response to the pressure of the lifting gas which is introduced when the main valve opens, whereby the device is operated when the lifting gas attains a predetermined pressure and a pressure differential across the main valve is not depended upon to actuate said main valve; s-aid device including an improved main valve assembly having an actuating piston for effecting opening movement of the valve.

A particular object of the invention is to provide an improved flow device, of the character described, wherein the main valve assembly comprises a movable valve element which is normally held closed by the lifting fluid pressure, together with a piston adapted to co-act with the valve element to move the same to an open position; said piston being constructed to prevent sticking or binding of the piston within its cylinder to assure positive operation thereof.

Another object of the invention is to provide an improved device, of the character described wherein the main valve element is operated by a piston which is actuated by the application of pressure thereto, whereby the use of bellows or other pressure actuated members is eliminated.

A particular object of the invention is to provide an improved flow device of the character described wherein the actuating piston for the main valve is constructed of telescoping members which normally move together as a single unit but which may move independently of each other in the event that one binds or does not slide freely, whereby either one of the members may function to individually control operation of the valve; the members being so arranged that the independent movement of the free member will function to free or release the inactive member so that subsequently both members will again function as a unit in a normal manner.

The construction designed to carry out the invention will be hereinafter described together with other features of the invention.

The invention will be more readily understood from a reading of the following specication and by reference to the accompanying drawing, wherein an example of the invention is shown, and wherein:

Figure 1 is a view, partly in section and partly in elevation of a ow device, constructed in accordance with the invention, and showing the main valve and pilot valve in closed position,

Figure 2 is a similar view of the lower portion of the device, with both the main valve and pilot valve in open position,

Figure 3 is an enlarged, horizontal, cross-sectional view, taken on the line 3 3 of Figure 1,

Figure 4 is a horizontal, cross-sectional view, taken on the line 4-4 of Figure 1, and

Figure 5 is a sectional detail of the actuating piston for the main valve.

In the drawings the numeral Il] designates a well tubing string or conductor which extends through a well bore (not shown). The well liquids which enter the lower end of the bore ilow into the lower end of the tubing string and rise upwardly therein to a predetermined level in accordance with the particular well conditions. A plurality of well ow devices for controlling the admission of an auxiliary lifting fluid into the tubing string to lift the well liquids to the surface are adapted to be mounted -at various elevations or levels in the string and only one of these devices A is illustrated herein.

The device A comprises a tubular housing which is constructed of an upper section Il and a lower section I2, which sections are connected together by a tubular coupling I3 having an axial bore I3a. The lower section I2 is formed with a bore I4 and a reduced counter bore I5 at its lower end. The lower portion of the section I2 is threaded into the upper end of the bore I6 of an enlarged boss I'I which is welded or otherwise secured to the exterior of the tubing string I0. The upper portion of the bore I6 communicates through a radial port I8 with a tubing inlet opening I9 whereby a flow from the bore I6 into the interior of the tubing may occur. An internal annular flange 20 is formed within the boss Il and a valve housing 2| is arranged to thread in the lower end of the bore I6 of said boss in abutting relation with the underside of the fiange. The valve housing 2| has its lower end closed by a cap 22 having an inlet port 23 in its lower end. With this arrengement the auxiliary lifting fluid which is within the annular space between the well bore and the well tubing may enter the valve housing and may ow upwardly through the bore 2Ia thereof, into the boss I1 and then through the openings I8 an I9 into the well tubing.

For controlling this ow or admission of auxiliary lifting fluid into the tubing a main valve 24 is mounted within the valve housing and has a guide stem 25 projecting upwardly into the bore I6 of the supporting boss I'I. The valve is arranged to engage an annular valve seat 26 within the valve housing and when in a seated position shuts off a ow through the bore 2Ia of said housing. The valve has its head exposed to the pressure of the lifting fluid exteriorly of the tubing with the result that this pressure normally maintains the valve in a seated position. The guide stem has its external surface grooved longitudinally so that when the valve is in an open position a flow through the bore 2Ia and upwardly through the grooves may occur.

For moving the valve 24 to a lower or unseated position to admit the lifting fluid into the tubing, an operating piston B is slidable within the bore I4 of the lower section I2 of the device. This piston is constructed of an inner cylindrical member 21 and an outer cylindrical member 28. The inner member is formed with an axial bore 29 extending entirely therethrough and an operating stem 3U has its upper end threaded into the lower end of this bore. The stem 30 is adapted to engage the upper end of the guide stem 25 of the main valve, whereby when the piston B is moved downwardly, the main valve is unseated or opened. rl'he inner member 21 of the piston B has an external annular shoulder 3| located near its lower end and this shoulder is adapted to be engaged by the lower edge of the outer piston member 28 which is formed with a bore 32 and which ts over the inner member 21 in telescoping relationship. The upper end of the bore 32 of the outer piston member is reduced as' shown at 33a and this reduced portion is in registration with the bore 29 of the inner section.

Ordinarily the members 21 and 28 of the duplex piston B move as a unit and obviously when they move downwardly the engagement of the operating stem 30 with the guide stem of the valve 24 moves said valve from its seat to admit lifting uid into the tubing. In the event that either the member 21 or the outer member 28 becomes jammed or stuck in the section I2, the other section may still undergo movement and its movement will effect a release of the member which has become jammed. Thus, the use of a duplex piston will assure a positive operation thereof even though one section may have become temporarily inoperative; this is one of the features of the present invention.

As has been explained the lifting fluid pressure is acting against the main valve 24 and through said valve acts upon the operating stem 30 to normally hold the piston B in a raised position. For controlling the operation of the piston in order to move said piston downwardly and thereby open the valve, a pilot valve 33 is mounted within the upper section I I. This valve is normally seated upon a valve seat 34 which is threaded into the upper end I3a of the intermediate coupling I3. Fluid inlet ports 35 which extend through the wall of the section II establish a communication between the interior and exterior of the said section and it is apparent that when the pilot 33 is raised, the lifting fluid pressure may act through the bore I3a of the coupling I3 and against the upper end of the piston B. The cross-sectional area of the piston B is greater than the cross-sectional area of the main valve 24 and it will be apparent that the admission of pressure to the upper end of the piston B will result in said piston moving downwardly and opening the valve 24. Such opening of the valve 24 will admit lifting fluid into the well liquid column within the tubing string I0.

The pilot valve 33 is attached to the lower end of a valve stem 36 which has its upper reduced end 36a extending upwardly from the section II. An upper coupling member 31 is threaded into the upper end of the section II and has a cap member 38 threaded into its upper end. A flexible disk 39 which may be constructed of rubber, leather or other flexible material has its peripheral portion clamped between the coupling 31 and the cap 38. 'lhe reduced upper end 36a of the pilot valve stem extends through the disk and is clamped to the central portion thereof by Washers 48 and nuts 4I. The cap 38 has a chamber 42 within which a suitable fluid or liquid is contained. When the pilot valve is seated the fluid level is as shown in Figure 1 but said pilot is raised, the liquid within the chamber 42 completely rills said chamber and acts as a positive stop as well as a means for preventing rupturing of the disk 39 by excessive pressure. The pilot valve is normally urged toward a seated position by a coil spring 43 which has its lower end engaging a nut 44 which is threaded on the stem 36; the upper end of the spring engages an internal shoulder 45 provided in the lower end of the upper coupling 3|. 'rhe spring 43 is adjusted to exert a predetermined pressure on the pilot Valve and this pressure must be overcome before the pilot is moved to an open position.

The operation of the device is obvious. The parts are normally in the position shown in Figure 1 with the spring 43 holding the pilot valve closed and the lifting fluid pressure maintaining the main valve 24 in a seated closed position. The lifting fluid pressure is, of course, acting within the interior of the upper section II and is acting on the lower portion of;V` the exible disk 39 as well as the exposed portions of the valve stem. When the'lifting fluid pressure exteriorly of the tubing reaches a p-oint suflicient to overcome the pressure of the spring 43, the pilot valve 33 is opened and the pressure of the lifting fluid is admitted through the bore I3a of the intermediate coupling I3 to the upper end of the duplex piston B. This pressure acting upon the piston will move said piston downwardly whereby the operating stern 30 will unseat the valve 24. When this occurs the lifting fluid pressure is admitted through the bore 2 Ia of the valve housing 2 I, through bore I5 of the boss and openings I8 and I9 into the tubing. As explained the admission of lifting fluid into the liquid column will raise a portion of the well liquids within the tubing to the surface.

The main valve 24 remains open until the pressure of the lifting fluid exteriorly of the tubing falls below the point at which the spring 43 is set and at such time said spring will again Iclose the pilot valve. Closing of the pilot valve will shut off the pressure from the upper end of the piston B and the pressure acting on the main valve 24 will again move the main valve to its seated positionl such movement returning the piston to its upper or raised position. To permit the escape of any pressure trapped between the upper end of the piston B and the pilot valve 33, an inclined relief passage 46 is formed in the operating rod 30 and thus this trapped pressure may escape to allow upward movement of the piston and closing of the main valve. The parts remain in this position until the lifting fluid pressure is again increased suiciently to open the pilot valve at which time the cycle is repeated.

As has been pointed out the important feature of the invention is the duplex piston B. It has been found that in certain areas the outer member 28 of the piston may stick to the wall of the bore I4 in which event the operation of the piston would be impaired; however, by providing the inner member 21 any sticking of the outer member will not interfere With the operation since the section 21 may function independently of the outer member; actually, the subsequent movement and re-engagement of the member 21 with the stuck outer member 28 will act to jar the outer member loose. This is also true if the lower portion of the inner member should adhere or become stuck within the bore. Thus, the duplex piston provides an operating means which will effectively open the main valve whenever the pressure of the lifting fluid exceeds a predetermined point sunicient to open the pilot 33.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. A well flow device including, a housing having a flow passage which has an inlet communieating with the exterior of the housing, there being a pressure existing exteriorly of said housing, a main valve element in said passage for controlling flow through said passage and having one end exposed to the pressure exteriorly of the housing, whereby said element is held in a closed position by said pressure, an actuating piston slidable in the housing above the valve element and engaging said element whereby downward movement of the piston will move said valve to an open position to permit flow through the passage, said piston comprising a pair of telescoping sections which sections intert with each other so that when in a fully telescoped position, the sections present an outer continuous surface of the same diameter, said housing having means for establishing communication between the upper end of the piston and the space exteriorly of the housing, and means controlled in its actuation by the pressure exteriorly of the housing for controlling the admission of pressure to the upper end of said piston, whereby when the pressure exteriorly of the housing reaches a predetermined point, said last named means is actuated to permit said pressure to act against the piston and thereby move said piston and open the main valve element.

2. A flow device as set forth in claim 1, together with means associated with the piston for bleeding the pressure from above said piston after the same has been actuated and the pressure responsive means has shut off the pressure acting against the upper end of said piston.

3. A flow device as set forth in claim 1, wherein the effective cross-sectional area of the actuating piston is greater than the effective cross-sectional area of the Valve element, whereby opening of the valve is assured.

4. A flow device as set forth in claim 1, wherein the pressure responsive controlling means is a spring-loaded pilot Valve which is normally in a seated closed position and which is opened only when the pressure exteriorly of the housing reaches a predetermined point.

5. A well How device including, a tubular housing having a flow passage which has communication with the exterior of the housing, there being a pressure existing in the area outside of said housing, a valve seat in said passage, an upwardly seating valve adapted to engage the seat and having its lower end exposed to the pressure exteriorly of the housing so as to be held in a seated position by such pressure, an axial extension on the valve projecting upwardly into the housing, and an actuating piston slidable within the housing above the valve and arranged to engage the valve extension, whereby downward movement of the piston results in a downward movement and unseating of the valve to permit flow through the flow passage, said piston comprising an inner body and an outer sleeve telescoping and slidably mounted on said body, the body and sleeve normally moving as a single unit and moving independently of each other only in the event one of said parts binds during its intended movement.

6. A well flow device as set forth in claim 5, wherein the body member of the piston has an axial bore, a downwardly projecting shank secured within and closing the lower end of the bore and adapted to engage the extension on the valve, and a bleeder port within the shank extending from the bore of the body to the exterior of said shank.

'1. A well flow device as set forth in claim 5, together with means for conducting the pressure exteriorly of the housing to the upper end of the piston, and means actuated by the pressure exteriorly of the housing for controlling the flow of pressure through said conducting means, whereby the piston is actuated to open the main valve only when the pressure exteriorly of the housing reaches a predetermined point.

8. As a sub-combination in a Well ilow device. an actuating piston including, a cylindrical body having an axial bore extending therethrough, a

shank secured in the lower end of and closing the bore of the body, and a generally tubularV member having its major portion surrounding the body and having its end portion formed with a reduced bore which communicates with the bore of the body, the reduction in bore size forming an internal annular stop means within the tubular member which stop means overlies and is adapted to engage one end of the cylindrical body to limit telescoping movement of the tubular member with respect to the body.

9. The sub-combination set forth in claim 8, wherein the shank is fiuted and also wherein a reduced port extends radially through the shank and establishes communication between the bore of the body and the space exteriorly of the shank.

JAY L. ROBISON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date '115,715 Weber Dec. 9, 1902 162,627 Fink June 14, 1904 2,342,301 Peters Feb. 22, 1944 2,385,316 Walton Sept. 18, 1945 2,391,605 Walton Dec. 25, 1945

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