US1836843A - Pneumatic swab - Google Patents

Description

Dec. 15, 1931. H. w. FLETCHER PNEUMATIC SWAB Filed Oct. 14, 1950 Hm Lb W. FLETCHER INVENTOR 1%. BY GQlQ/Uu ATTORNEY Patented Dec. 15, 1931 UNITED STATES PATENT OFFICE I HAROLD W. FLETCHER, OF HOUSTON, TEXAS, ASSIGNOR T HUGHES TOOL COMPANY,

.- OF HOUSTON, TEXAS, A CORPORATION OF TEXAS PNEUMATIC SWAB Application filed October 14, 1930. Serial No. 488,567.

M invention relates to pneumatic swabs emp oyed in raising'liquid from deep wells. The improvement lies largely in the structure of the foot valve controlling the inlet of li uid to the eduction tube.

y invention is an improvement upon the standin valve shown in" my prior application file August 11,1930, S erialNo. 47 4,358.

It is an object of theinvention to provide a foot valve at the lower end of the eduction tube which may be'automatically secured in position during operation.

I also have as an object the provision of an injector effect in causing the liquid to flow into the eduction tube so as to obtain the desired load of liquid above the swab plunger.

The invention resides in the provision of a foot valve easily set in position and acting as a support for the swab plunger and a control Ineans'for the liquid from the well.

In the drawings Fig. 1 is a central longitudinal section of the upper end of the well swabbing device.

Fig. 2 is a similar section of the lower end thereof with my invention applied thereto.

The well has an outer casing 1, the upper end of which is equipped with a special casing head 2 with a lateral outlet 3 thereon for the liquid. Said casing head has a coupling 4 at its upper end by means of which it is connected with an elongated bull plug or housing 5 closing the upper end of the easing. Said head has an inner shoulder 6 to support the head 7 of the eductlon tube. A pressure fluid inlet 8 connects through the casing head and the head 7 of the eduction tube with the space 9 between the eduction tube 10 and a larger concentric pipe 11.

The pipe 11 conducts the pressure fluid to the lower end of the eduction tube. It is connected by a coupling 12 to a housing or shoe 13. Said shoe is closed at its lower end except for a liquid inlet opening 14.

The lower end of the eduction tube 10 fits tightly in said shoe 13 as shown at 15 and has lateral openings 16 therein to admit pressure fluid from the space 9 to the interior of the eduction tube. The interior of the shoe 13 has a downwardly tapered seat 17 to receive the foot valve member shown generally at A.

air, the liquid in Said standin valve comprises a cylindrical housing 18 tting the eduction tube. The lower end has a valve cage 19 of reduced external diameter, the lower extremity of which fits the seat 17 A valve 20 in said cage 'is limited in its upward movement by a transverse pin 21. The intermediate portion of the valve casing 18 is recessed at 22 on its outer periphery to provide space for the inlet of pressure fluid. The upper end of the standing valve member is tapered upwardly at 23 to interfit with a wedging member 24.

Said wedging member is'tubular and fits within the eduction tube. Its lower end is flared to fit over the foot valve member and is slotted longitudinally at 26 to allow spreading in wedging over the foot valve, thus locking the standing valve in position. The upper end of the "wedge member forms a seat for the swab plunger 27.

The interior of the valve casing 18 has an upwardly-converging passage 28 into which projects a nozzle 29 connected with the lower valve chamber. A Venturi passage 35 is formed above the nozzle.

The swab plunger 27 is of the usualconstruction. It has an upwardly'closing valve 30 which is normally held out of its seat by gravity.

In operating my device, movement of the plunger through fluid pressure will lift the load of liquid above it to the surface and discharge it through elongated ports 31 and the outlet pipe 3 to storage. The plunger will pass the ports 31 into a closed nipple 32 where it will be stopped by fluid entrapped therein, and the valve 30 will be forced open. The air or other ressure fluid will exhaust through the outlet and the'plunger will begin its drop again to the bottom.

When the air pressure is relieved in the eduction tube following the exhaust of the the well will open the valve 20 andrise in the eduction tube. The pressure fluid will enter continuously through the openings 16 around the nozzle 29 and will bubble through the entering oil, thus having an injector effect creating a low pressure area about the upper end of the nozzle and drawthe upward ing liquid into the tube. The level of liquid of the liquid in the well.

The falling plunger will be cushioned in sinking to the seat -on the member 24, and the valve will close because of the gas pressure below it and the ,air or gas will then accumulate beliw the plunger which will be raised with its load to the surface.

When the device is to be withdrawn, the wedging member 24 may be removed by a spear engaging therein, and then the foot valve may be similarly withdrawn.

By the use of the invention, the desired level of liquid in the eduction tube above the plunger may be obtained even with a relatively low head standin in the well, I am enabled to use my swa in wells with low formation pressure.

What I claim as new is:

1. In a pneumatic swab, an eduction tube, a plunger therein having a fluid passage therethrough, a normally open valve therein adapted to be closed upwardly by fluid pressure, a removable foot valve housing at the lower end of said tube, and means to wedge said valve housing in position.

2. In a pneumatic swab, an eduction tube, a plunger therein having a fluid passage therethrough, a normally open valve therein adapted to be closed upwardly by fluid pressure, a removable foot valve housing at the lower end of said tube, and means to wedge said valve housing in position including a downwardly flaring wedge member telescoping over said casing.

3. In a pneumatic well swab, an eduction tube, a foot valve housing at the lower end thereof, a valve member in said housing to control the inlet of liquid thereto, means to introduce pressure fluid to said casing above said valve member, a tapered upper end on said housing, means engaging therewith to removably fix said casing in said tube, and a swab above said casing engaging means.

4. In a pneumatic swab, an eduction tube, a swab plunger therein having a fluid passage therethrough, normally open valve therein adapted to be closed upwardly by fluid pressure, a foot valve member below said swab, an upwardly tapered end on said member, and means to engage said tapered upper end to latch said member in position, said latching means forming ;a seat for said plunger.

5. In a pneumatic swab, an eduction tube, a swab plunger therein having a fluid passage therethrough a normally open valve therein adapted to be closed upwardly by fluid pressure, a foot valve member below said swab, and means engaging said valve member to latch it removably in position and also serve to support said plunger.

6. In a pneumatic swab, an eduction tube, a swab plunger therein having a fluid passage therethrough, a normally open valve therein adapted to be closed upwardly by fluid pressure, a foot valve housing in said tube, a valve controlling the passage of liquid to said housing, an upwardly directed nozzle above said valve, and means to conduct pressure fluid to said housing about said nozzle.

7. In a pneumatic swab, an eduction tube, a swab plunger therein having a fluid passage therethrough, a normally open valve therein adapted to be closed upwardly by fluid pressure, a foot'valve housing in said tube, a valve controlling the passage of liquid to said housing, an upwardly directed nozzle above said valve, a Venturi passage at the end of said nozzle, and means to conduct pressure fluid to said housing about said nozzle.

8. In a pneumatic well swab, an eduction tube, a swab plunger therein movable freely from the lower to the upper end of said tube, a foot valve below said swab, means to introduce pressure fluid below said swab, and means responsive to the flow of said pressure fluid to raise the level of liquid in said eduction tube above the level of liquid in the well.

9. In a pneumatic well swab, an eduction tube, a swab plunger therein movable freely from the lower to the upper end of said tube, means to introduce pressure fluid below said swab, and means responsive to the flow of said pressure fluid toraise the level of liquid in said eduction tube above the level of liquid in the well.

10. In a pneumatic'well swab, an eduction tube, a swab plunger in said tube, a foot valve at the lower end of said tube, an injector above said valve," and means to introduce pressure fluid through said injector and to raise the level of liquid in said tube above the level of the liquid in the well. 1

In testimony whereof, I hereunto affix my signature, this the 29th day of September, A. D. 1930.

HAROLD W. FLETCHER.

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