US2142376A - Flow controlling valve - Google Patents

Description

Jan. 3, 1939. E. A. RoDGERs FLOW CONTROLLING VALVE Filed Aug. 17, 1936 2 Sheets-Sheet l lJan. 3, 1939. l E, A RODGERS 2,142,376

FLOW CONTROLLING VALVE PatentedA den. 3, i939 UNITED PATENT oI-Flce 5 Claims.

This invention relates to ow controlling valves for oil and gas wells and the like.

It has for its principal object to produce a simple yet practical, dependable and durable 5 float and balanced pressure valve device that can be readily placed operably in a well to malntain a definite liquid level and a-gas pressure head thereabove in the well casing.

Another object is to produce a flow controlling l oat valve that acts quickly to close when the liquid in the well casing drops to a non-buoyant level and when closed positively prevents escape of gas. I

A further object is to produce a valve device by l the operation of which a complete separation of oil and gas is attained.

A still further object is to produce a practical flow controlling valve that can be opened and closed, at will, by regulation of pressures in the v well casing and the iiow line tubing.

A construction designed to carry out the invention will be hereinafter described, together withother features of the invention.

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

Figure l is a view, partly in side elevation and partly in vertical section, showing a flow controlling valve assembly operably installed in a well;

Figure 2 is a vertical lsection, on an enlarged scale, of one practical construction and arrange ment of a valve assembly; y

Figure 3 is a cross section on the line 3-3 of Figure 2;

Figure 4 is a cross section on the line 4-4 of Figure 2; and.` v

Figure 5 is a vertical section of a modified construction and arrangementzoi a valve assembly.

Referring now tothe drawings the numeral I0 designates generally an oil well in which a tubular lining or casing II is provided, said casing being closed at its upper end by an ordinary head, shown conventionally at I2, and its lower end terminating, in accordance with the usual practice, at the impervious stratum I3 which,

overlies the gas producing formation or sand I4, next below which is the oil producing formation or sand l5.` This is apractical installationin the conservation control of productive wells and the rehabilitation of declining or non-productive wells.' However, the valve of the present invention is not limited to the particular instal- (Cl. 16S-2) lation illustrated, but is obviously adaptable for other installations for the maintenance of a liquid level in the well above a certain minimum and the stoppage of outflow and escape of gas.

A t the lower end of the flow line tubing IB, 5 which lextends downwardly in the casing II from the head l2, is a hollow shell or valve shield Il, to the lower end of which is attached the reserf voir tube I8. As shown in Figure l, the tube i8 extends down to near the bottom of the well 10 reservoir Il and is closed at its lower end by a plug or cap 20.

Some distance above the plugged or capped end 2, or at least above the water level (if there be any water present) in the reservoir lg, the 15 tube I8 is provided with a series :of apertures 2l, above which is a bushing or stopper '22.. Extending axially throughthe stopper 22, with its lower end opened and below the apertures 2I of y the tube I8, is an inner ow tube 23, 'the upper 20 portion of said tube 23 extending up into the vhollow shell or v'alve shield I'I- and having its upper end portion 24 communicating with a oat chamber 25 in the shell or shield I'I, as and for the purpose to be presently more fully described. 25

Preferably, as shown, the shell or shield II comprises a cylindrical body member 26 at the upper end of which is an attached head 21 having a reduced neck or coupling extension 28 to which the flow une tube le is attached, while at 30 its lower' end is` provideda similar head 29, to

the reduced neck or coupling portion 30 of which the reservoir tube I8 is attached.

The oat chamber 25 comprises an inner cylinder 3| which is preferably supported at its lower 35 end on the shell or shield cylinder 2B by radial struts 32. The upper end portion of the inner cylinder 3l is attached to the shell or shield cylinder 26 by tubular struts 35 which are open at their inner ends to communication with the float 40 chamber 25, as at 36, and at their outer ends to communication with the space in the well casing I I, as at 3l.

The upper end of the oat chamber cylinder 3| is closed by a head 3s, while in the 1cwer ena 45 of the cylinder 3l is fitted a plug 3 9 having a central opening in which the end portion 24 of the flow tube 23 is fitted. Surrounding said central opening, on the inner side of said plug 39 is an annularly grooved valve seat 40 to receive a counterpart valve head 4I mounted on' the lower end of a hollow oat cylinder 42, which latter is closed at its upper end, as at 43, and may be provided at its lower endportion with aperf tures 44' through which, if said cylinder 42 .be

submerged in the cylinder 3|, a certain amount; of uid will enter the float cylinder 42, but not in quantity enough to fill it, because there is always suiicient air pocketed in the float cylinder to make it buoyant. However, in some cases, the float cylinder may be made without the apertures 44, in order to have more buoyancy, but withless pressure balancing effect should the liquid level fall below a given minimum, as will v be later more fully described.

To center the float cylinder 42 in 'the oat chamber 25, the cylinder is preferably provided near its lower end with radial lugs 45 which bear slidably at their outer endsl on the inner face of the float cylinder 3|. Obviously, an upper set of the lugs 45 may also be provided, if desired, but in most cases the lower set alone will suffice for centering the float cylinder 42 and guiding the annular valve portion 4I to its seat inthe groove 40 of the plug 39 at the bottom of the float chamber cylinder 3|.

In the annular valve-seating grooveY 40 the plug 39 is provided with a series of apertures 40 through which fluid flow communication is established between the interior of the iloat chamber 25 and the interior of the shield shell 26 when the valve head 4| is lifted from said annularly grooved seat 40. As shown, the valve head 4|- comprises a circular body which is screw-threaded annularly and inserted as a plug in the internally screw-threaded lower end portion of the float cylinder 42. On the under side of the body portion 4| is an annular seating portion 4I', the

corner portions of which are preferably beveled to lit with accuracy in the annular groove 40 whose marginal wall portions are correspondingly beveled. Obviously, said seat portion 4| may be formed integrally with,the body portion 4| or otherwise provided thereon in any approved way.

By providing the annular seating portion 4I there is a limited space 4I" above the central inlet opening where the iiow tube 23 is connected to the plug 39, whereby to receive the fluid from said tube 23 while the valve head 4| is seated, by which provision the opening of the valve is materially aided by the iluid pressure in said tube 23, yet, when the liquid level in the well falls below the minimum at which the iloat cylinder 42 is lifted by its buoyancy, the relative pressures in the well are such that the valve 4| is held seated in the groove 40 and eifectivelyprevents escape of gas, that is to say, there is at least a balanced pressure above and below the closed valve whereby it remains seated in its closed position until the liquid level risesA in the well sufilciently to float the cylinder 42 and thereby lift the valve 4| from the seating groove 40.

Obviously, by the maintenance of a gas pressure head` above the level of the body of liquid in the well, at whatever stage the liquid level may be, and which is accomplished by sealing off the space between the well casing I I and ilow line tubing I6 some distance above the location of the controlling valve device of the 'present invention, the flow of `the liquid from the welly is controlled and at the same time no gas can escape through the controlling valve device because, in the first place, the construction, installation and operation oi the device is such that` an effective separation of the gas and liquid contents of the well is attained so that, normally, when the liquid is at or above the minimum level at which the float is raised and the valve opened, only liquid is delivered from the well through the flow controlling valve device to the ow line tubing I6, and, secondly, if the liquid level falls to near the bottom of the float chamber cylinder 3|, no gas will escape-because of the liquid seal above the openings 40,even if the valve 4| is unseated from the groove 40 at the time; and, should the liquid ,level fall below the bottom of the float chamber cylinder 3|, still no gas will escape because, due to the weight of the valve cylinder 42 and the gas pressure in the chamber 25 above and surrounding the valve cylinder 42, which pressure is at least equalized with that outside of the float chamber cylinder 3|.

In the use of the valve device of the present invention, the flow line tubing I6, with the valve assembly attached to the lower end thereof, is lowered into the well until the valve shell or shield I1 reaches the position in the region where it is desired to maintain the minimum liquid level at which the iloat valve cylinder 42 is buoyant and the valve member 4| is lifted from its seat in the annular groove 40 of the plug 39 at the bottom of the oat chamber cylinder 3|.

The approximate minimum valve-opening oil level is indicated at 46 in Figures 1 and 2 of the drawings, and at all levels thereabove the valve remains open, but upon the level falling below the minimum the valveimniediately closes. Y

A gas pressure head-is usually maintained in the well casing above the liquid level, either by the natural gas that becomes separated from the liquids in the well and rises thereabove, or by airor gas pressure supplied artiilcially to the well casing for the purpose. 'I'his pressure above the liquid, together with the natural pressure of the liquid coming from the producing formation, forces the liquid in the region of the apertures 2| of the pipe I8 into the pipe through said apertures, the free gas separating and rising upward through the body of liquid and only the non-va.- porized gas enters with the liquid. By reason of the pipe 23, of relatively smaller diameter than the pipe I8, being extended below the series of apertures 2|, the liquid is further separated from the free gas and passes up through said pipe 23 into the iloat chamber just beneath the valve member 4 I, and, as the float cylinder 42 is buoyed up by the liquid being at or labove the minimum level in the well casing and entering the float chamber 25 through the tubular upper struts 35, the valve head 4| is lifted above the seating groove 40, whereby the liquid flows into the float chamber 25 through said tube 23, out through the openings 40 in the grooved portion 40 of the plug 39 and up through the space between the shell or shield Hand the float chamber cylinder 3|, and into the ilo'w line tubing I6, either under the pressure within the well or suction of a pump attached to or applied i'n the flow line tubing I6, as the case may be.

Should the liquid level fall below the minimum the iioat cylinder 42 will drop and seat the valve head 4I in the groove 40 of the plug 33 at the bottom of the iloat chamber cylinder 3|, whereupon there is a positive stoppage of outilow through the openings 40', as the valve head 4I remains seated until again lifted bythe buoyancy of the iloat cylinder 42. 'I'hat is to say, the natural gas or artificial pressure in the w'ell casing will act to'close rather than open 4the valve and the elfe-ct of pumping in the flow line tubing will also be to close the valve. However, if a back pressure exists or is specially created in the flow line tubing I6 greater than the pressure in the 'Il amasro well.. the valve head 4| will be unseated from the groove I0. It will thus be seen that the valve can be controlled from the surface by regulating the pressures in the flow line tubing and the well casing. So, too, if it is desired to wash the well casing, the washing liquid can be supplied to the casing, thereby buoying and lifting the float valve I and passing up,l through the iiow line tubing jlB; or, if desired, the washing liquid may be supplied under pressure through the flow line tub'ng I6, thereby filling the space between the shell or shield and the oat chamber cylinder 3| whereby to pass through the apertures 40 and force the valve'portion 4| from its seat in the.

groove 40 and passing the liquid out through the upper hollow struts 35` and also downthrough thelpipe 23, and out through the apertures 2| in the pipe i8, whence it circulates up through the well reservoir and into the casing Il.

A modification of the valve structure and arrangement is shown in Figure of the drawings, wherein the lower end of the shell or shield IIa is closed by a plug Il' and the float chamber vcylinder 3|a by a plug 41 having a central opening 41 which formed with a counterpart seat for a semispherical valve member to be vpresently described, the liquid intake to the inner fioat chamber cylinder 3|a being directly through lower tubular struts 32 and also through the upper tubular struts 35 as in the first herein described structure. In this second modification the float cylinder 42a is open at its lower end, as at 48, and

the valve member t9, which has a semi-spherical seating portion, is attached to the lower end of an axially disposed stem 5|) whose upper end portion is secured, as, at 5|, in the head 43a of the float cylinder Ma, the lower end portion of said stem 50 being supported and braced by a spider frame 52 secured in the lower open end portion of the float cylinder 62a.

lThe stem 50 may be solid, as shown, but, obviously, it may be made tubular with its upper end closed and provided at its lower end with an opening or openings whereby to increase the buoyancy of the float cylinder 42a.

The operation of this'modifed valve assembly is the same as that of the first herein described structure and assembly except that the liquid of the well is admitted to the float chamber 25a directly through the tubular struts 32', 35, at which points the liquid and free gas separation takes place, instead of occurring at the lower level of the apertures 2| in the pipe I8 of the first herein described valve assembly. In some wells wherethere is but comparatively little gas production this second described valve assembly is practically effective, while in other wells where there is free gas in greater proportion to the liquid production the gas and liquid separation and intake of the liquid into the pipe I8 at the lower depth is the more effective.

It is here noted that in an installation of the valve device of the present invention for controlling the flow of an oil well, as illustrated in Figure l of the accompanying drawings, the oil level is maintained above the gas and oil producing strata or formations, but in an installation in a gas well the liquidlevel is maintained below the gas producing stratum or formation, in which latter case the present invention is adaptable for other installations.

Obviously, the valve vstructure and assembly and the application thereofmay be vmodified other than herein shown and described within the spirit and scope of the invention as defined in the ap-l pended claims. limited to the particular construction and arrangement shown in the accompanying drawings. l

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

'1. A flow controlling valve device -for oil and gas wells and the like, comprising, a tubular shield having an outlet opening in its upper yend portion and being supportedly attachable to the flow line tubing of the well and communicable with. the tubing through said outlet opening, an inner float chamber cylinder supported axially in said tubular shield and spaced therefrom, said float chamber cylinder having an axial opening 'in its bottom end communicably connected with liquid flow tubing from below in the well and an annular series of openings surrounding said axial opening for communication between the chamber and the interior of said shield but otherwise closed to communication with the shield, a float in said float chamber cylinder, a valve lmember carried by said float at the bottom thereof and in controlling relation to said axial opening and said annular series of surrounding openings in the ,bottom of the float chamber cylinder, and means of communication between the uppermost interior portion of said float chamber cylinder and the space inthe well outside of said shield.

2. A flow controllmg valve device for oil and gas wells and the like, comprising, a hollow cyl lindrical shield having an outlet opening in its The invention, therefore is not' outside of the shield, said float chamber cylinder having'an axial opening lin its bottom with a pipe connection for communication between the cylinder and the lower well space outside of the shield and an annular series of openings for communication between said cylinder and the interior of said shield -but otherwise closed to such communication, a float in said float chamber cylinder, and a valve member carried at the bottom of the float to control said axial opening and open and close said shield-communicating annu-'- lar series of openings. g

3. A flow controlling device arranged to be suspended within a well by a tubing string including, a tubular shield having an opening at its upper end communicating with the tubing, an inner float chamber cylinder supported withinr the shield and spaced therefrom, the cylinder having an axial opening in its lower end communicably connected with liquid flow tubing from below in the well andan annular series of openings surrounding the axial openings for establishing communication between the chamberv of the cylinder and the interior of the shield, a iioat in the chamber yof the cylinder, a valve member carried by the lower end of the oat and in controlling relation to said axial opening and the annular series of openings, the shield being provided with passages for establishing communication between the uppermost portion of the chamber and the space in the well outside of said shield.

4. A ow controlling device arranged to be suspended within a well by ar tubing string including, a tubular shield having Aan opening at its uppermost end communicating with the tubing, an inner float chamber cylinder supported within the shield and spaced therefrom, the cylinder having an axial opening in its lower end communicably connected with liquid flow tubing from below in the well and an annular groove surroundingthe upper end of the opening, the lower end of the cylinder having an annular series of openings surrounding the lower end of the axial opening and communicating with the annular groove, whereby communication is established between the chamber of the cylinder and the interior of the shield, a oat in the chamber of the cylinder, an annular valve member at the lower end of the float for engaging the groove so as to open and close the axial opening and the annular series of openings, and means of communication between the uppermost interior portion of the chamber and the space in the well outside o! .said shield.

5. A flow controlling device arranged to be suspended within a well by a tubing string including, a hollow cylindrical shield having an opening at its upper end communicating with the tubing, a hollow float chamber cylinder supported in surroundingly spaced relation within said shield by strut members at the top of the cylinder and similarlytherebelow, the upper strut members being tubular so as to establish communication between the uppermost interior portion of the chamber of the cylinder and the well space outside of the shield, said cylinder having an axial opening in its lower end with a pipe connection 'for establishing communication between the chamber and the lower well space outside of the shield and an annular groove surrounding the upper end of the opening, the lower end of the cylinder having an annular series of openings surrounding the lower end of the axial opening and communicating with the annular groove, whereby communication is established between the chamber and interior of the shield, a oat in said chamber, and an annular valve member at the bottom of the float for engaging the groove so as to open and close said axial opening and the annular series of openings.

ELBERT A. RODGERS.

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