US2257523A

US2257523A - Well control device

Info

Publication number: US2257523A
Application number: US374383A
Authority: US
Inventors: Chester A Combs
Original assignee: B L SHERROD
Current assignee: B L SHERROD
Priority date: 1941-01-14
Filing date: 1941-01-14
Publication date: 1941-09-30
Anticipated expiration: 1958-09-30

Description

sept. 3o, 1941. C1 A. COMES 2,257,523

`WELLCONTRQL DEVICE Filed Jan. 14, y1941 2 sheets-sheet 1 H mmm lllll llll' m e; er oms. ira-5.2.67 l C Sept. 30, 1941. c. A, coMBs 2,257,523

WELL CONTROL DEVICE Filed Jan. 14, 1941 2 Sheets-Sheet 2 n ay/df COMA?. 557.7. @7+

Patented Sept.` 30, 1941 UNITED STATES PATENT OFFICE 2,257,523 WELL CONTROL DEVICE Chester A. Combs, Benavides, Tex., assignor of thirty-three and one- Sherrod, Conroe, Tex. Application January 14, 1941, Serial No. 374,383

(Cl. S-232) 9 Claims.

This invention relates to improvements in flow control and more particularly to a novel device for controlling the flow of iiuids in oil wells, and it may be used either for wells that produce gas in insuiicient quantity to force the oil to the surface or for wells artificially pressured.

After the initial iiush production of an oil well, the reservoir of gas becomes depleted and usually salt water is present in considerable quantities. In a self-producing well, the oil at great depths is impregnated with gas in solution which, when rising, expands providing buoyance and lifting force to the oil.

If a well producing salt water is permitted to stand closed in for a period of time, the salt Water rises to a considerable height above the bottom opening of the tubing, hence the water which vrises part way when the choke or ow bean is opened, having little or no gas in the solution, fails to rise to the surface and is called dead Now, if the well casing has considerable pressure either natural or induced, it is possible to start the flow again by utilizing perforations in the tubing spaced at various elevations to accord with the casing pressure, salt Water percentage, etc. The perforations if left open after having accomplished their purpose are very wasteful of gas. The same is true if a means for closing said perforations fails to function either by staying open too long or by leakage.

The primary purpose of my invention is to supply simple practical means for elfectively controlling such perforatons and for tightly closing the perforations at the proper time.

A further object is to furnish a simple and inexpensive iiow control device and yet one which will be exceedingly eiiective for the purpose for which it is designed.

With the foregoing objects outlined and with other objects in view which will appear as the description proceeds, the invention consists in the novel features hereinafter described in detail, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims.

In the drawings:

Fig. 1 is a vertical sectional View partly in elevation of a portion of a well and showing one of my units with the parts in position to permit the flow of gas from the casing into the tubing containing the liquid.

lig. 2 is a similar view of the flow control device with the view taken at right angles to the one in Fig. 1.

third per cent to B. L.

Fig. 3 is a horizontal sectional View on the line 3 3 in Fig. 1.

Fig. 4 is a vertical sectional view of a detail on the line 4 4 of Fig. 2.

Fig. 5 is a horizontal sectional view taken on the line 5 5 of Fig. 2.

Fig. 6 is a vertical sectional view of a detail taken on the line 6 6 of Fig. 1.

Fig. 7 is a vertical sectional view of well casing and an elevation of a tubing string with a number of my control units interposed therein.

Referring to the drawings, 8 designates well casing in which a tubing string 9 is arranged. In accordance `with the invention certain sections I0 of the tubing are provided with one or more upper periorations Il for the admission of gas, and one or more lower perforations I2 for the discharge of liquid. This section of the tubing is surrounded by a jacket I3 which is of slightly smaller diameter than the inside diameter of the casing and has its ends closed and secured to the tubing by joints I4. The jacket with the tubing forms an annular chamber I5 in which the liquid passing through the perforations I2 may rise and fall, so as to control an annular hollow float I 6 lled with a non-volatile oil I l.

To take care of the severe pressures encountered in a well, the top and bottom of the float are connected to a vertically disposed hollow cell I8, which as best shown in Fig. 5, is provided with plane opposite side walls I9. Such walls can expand or contract and will therefore prevent breakage of the float due to the `unequal pressures at the interior and exterior of the iioat.

For counter-balancing purposes, a pair of links 20 are pivotally connected to the bottom of the float and their lower endsare pivotally connected to rocking levers 2| that are pivotally connected at their medial portions (as indicated at 22) to a collar 23 iixed to the tubing. The levers pivotally support links 24 from which are suspended an annular weight 25.

Above the float, a block 26 is arranged in the chamber I 5 and secured to the tubing. The block provides a passageway 21 placing the interior of the casing in communication with perforation II A valve seat 28 forming part of the passageway cooperates with a vertically reciprocating valve member 29 which is elevated by gas'pressure within the casing. The valve is closed by means of a pin 30 which engages its head. The pin projects radially from a horizontally disposed rocking shaft 3| xed to an arm or lever 32 that is pivotally connected to the top of the oat by a link 33.

As shown in Fig. 7, the units according to my device are arranged at various elevations spaced according to casing pressure, salt water percentage, etc. Each unit operates as follows. When the unit'l is above the liquid level in the tubing, the chamber I5 will be empty and the oat will be in lowermost position and the Valve 29 will be closed to prevent gas from the casing entering the tubing.

When the choke or iiow bean on the well is open releasing the tubing pressure, the casing pressure forces the liquid down and up through the lower end of the tubing to a certain height. If this elevation is over the valve of one oi my units, the liquid will enter the chamber I5 through the ports I2 and will compress ,the gas.

in the chamber above the liquid level. The liquid will cause the float to rise, hence link 33 will lift one end of the arm 32 to cause the linger 30 to move away from the valve 29. VThe pressure in the casingrwill open this valve and allow gas from the casing to enter the tubing. Hence the liquid in the tubing, above the valve willbe forced upward and out of the well and the casing pressure will force liquid froml a lower level into the t bing. VWhen sufficient liquid has been removed or made lighter by gas bubbles in the tubing column, the valve below the last-mentioned valve being open, as is vthe first, will begin to function due to reduced pressure in the tubing and relatively constant casing pressure.

The gas released into the tubing bythe lower valve will pass bythe ports and part of this gas will enter these ports replacing the liquid, on the same principle as a stock or chicken fountain. YVvhen the liquid is lowered sufficiently below theiioat, the latter moves downwardlyT and again Ycloses the valve 29. It is to be noted that this operation takes place when a lower valve has begun to function, and that the time required for the upper valve to close is determined by the size and number of perforations leading from the tubing into the chamber l5. Since the jacket 13- is ywelded to the tubing, there is no chance for leakage except at the orifice leading to and l through the valve.

While I have disclosed what I now consider to be a preferred embodiment of the invention, in such manner thatrthe same may be readily understood by those skilled in the art, I am aware that changes may be made in the details disclosed without departing from the spirit of the invention as expressed in the claims.

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

.1". In a iiow control device for wells having a casingwith tubing arranged therein, a jacket secured 4to a portionof the tubing and forming agas-,tight chamber, a port placing the interior of the tubing in communication with the lower portion of said chamber, a passageway placing the interior of the casing at the exterior of the jacket in communication with the interior of the tubingat a point above said port, a valve tocontrol the passing of gas through the passageway, -a` segregatedA from Athe tubing above said float, whereby gas may be trapped in the chamber by liquid rising therein-and means operatively-connecting the iioat to said valve to permit the valve to open when --the iioat rises and to close the valve whenthe float descends.

. 2,A In a flow control device for wells havingr a iioat in said chamber, said chamber being.

casing with tubing arranged therein, a jacket secured to a portion of the tubing and forming a gas-tight chamber, a port placing the interior of the tubing in communication with said chamber, a passageway placing the interior of the casing at the exterior of the jacket in communication with the interior of the tubing, a valve to control the passing of gas through the passageway, a hollow float in the chamber filled with non-volatile oil, and means operatively connecting the float to said valve to permit the Valve to open when the floatrises and to close the valve when the float descends. Y

3. In a flow control device for wells having a casing with tubing arranged therein, a jacket secured to a portion of the tubing and forming a gas-tight chamber, a port placing the interior of the tubing in communication with said chamber, a passageway placing the interior of the casing at the exterior of the jacket in communicationV with the interior of the tubing, a valve to control the passing of gas through the passageway, a hollow iioat in said chamber nlled with non-Volatile oil, a pressure-equalizing passageway extending through the float and having expansible and contractable opposite walls, and means operatively connecting the iioat to said valve to permit the valve to open when the iioat rises and to close the valve when the float descends.

4. In a iiow control devi-ce for wells having a casing with tubing arranged therein, a jacket secured to a portion of the tubing and forming a gas-tight chamber, a port placing the interior of the tubing in communication with said chamber, a passageway placing the interior of the casing at the exterior of the jacket in communication with the interior oi the tubing, a valve to control the passing of gas through the passageway, a oat in said chamber, counter-balancing means connected to the float, and means operatively Aconnecting the float to said valve to permit the valve to open when the float rises and to close the valve when the float descends.

5. In a flow control device for wells having a casing with tubing arranged therein, a jacket surrounding a portion ofthe tubing and forming with the latter a gas-tight annular chamber, a port placing the interior of the tubing in communication with the lower portion of said chamber to permit liquid from the tubing to ow into the chamber, a passageway placing the interior of the casing in communication with the interior of the tubing, a valve to control the passing of gas through said passageway, an annular floatV arranged in the chamber, and operating meansV for the valve operatively connected to the iioat and valve.

6. In a flow control device for wells having a casing with tubing arranged therein, a jacket secured to a portion ofthe tubing and forming a gas-tight chamber, a port placing the interior of the tubing in communication with said chambera passageway placing the interior of the casing at the exterior of the jacket in communication wit'h the interior of the tubing, a valve to control the passing of gas through the passageway, a float in said chamber, means operatively connecting the float to said valve to permit the valve to open when the float rises and to close the valve when the iioat descends, levers arranged in said chamber and having their medial portions pivotally connected to the tubing, means connecting the bottom of the oat to certain ends 01E 'the levers, a counter-weight, and means operatively connecting the other ends of the levers to said counter-weight- 7. In a flow control device for wells having a casing with tubing arranged therein, a jacket rsurrounding a portion of the tubing and forming with the latter a gas-tight annular chamber, a port placing the interior of the tubing in communication with the lower portion of said chamber, a passageway placing the interior of the casing in communication with the interior of the tubing, a valve to control the passage of gas through the passageway from the casing to the tubing, an annular float arranged in the chamber and guided by the tubing, diametrically opposite links pivotally connected to the bottom of the iioat, levers having their medial portions pivotally connected to the tubing and certain of their ends connected to the lower ends of the links, an annular counter-weight guided by the tubing, links extending upwardly vfrom the counterweight and connected to the other ends of said levers, and means operatively connecting the oat to said valve to permit the valve to open when the float rises and to close the valve when the float descends.

8. In a iiow control device for wells having a casing with tubing arranged therein, a jacket surrounding a portion f the tubing and forming with the latter a gas-tight annular chamber, a port placing the interior of the tubing in communication with the lower portion of said chamber, a block in the chamber between the tubing and jacket, a passageway extending through the block, a port in the tubing registering with said passageway, a valve in the passageway t0V close communication between the interior of the casing and the interior of the tubing, a rock shaft pivotally mounted in the block and provided with means for closing the valve, an arm arranged in the chamber and having one of its ends rigidly united with the rock shaft, an annular flo-at guided by the tubing and arranged in said chamber, and meansconnecting the float to the other end of said arm.

9. In a flow control device for wells having a casing with tubing arranged therein, a jacket surrounding a portion of the tubing and forming with the latter a gas-tight annular chamber, a port placing the interior of the tubing in communication with the lower portion of said chamber, a block in the chamber between the tubing and jacket, a passageway extending through the block, a port in the tubing registering with said passageway, a valve in the passageway to close communication between the interior of the casing and the interior of the tubing, a rock shaft pivotally mounted in the block and provided with means for closing the valve, an arm arranged in the chamber and having one of its ends rigidly united with the rock shaft, an annular float guided by the tubing and arranged in said chamber, means connecting the float to the other end of said arm, a counter-weight arranged in the chamber below the oat, and link and lever means pivotally connected to the tubing and operatively connecting the counter-weight to the float.

CHESTER A. COMBS.