US1769637A - Fluid-operated swab - Google Patents

Description

July 1, 1930.

H. w. FLETCHER ET L 1,769,637

FLUID OPERATED swAB Filed Oct 20, 1928 INVENTOR BY Q ATTORNEY Fig. I

Patented July 1, 1930 UNITED STATES PATENT OFFICE HAROLD W. FLETCHER AND NORMAN H. RICKER, OF HOUSTON, TEXAS, ASSIGNORS TO HUGHES TOOL OOMPANY, O15 HOUSTON, TEXAS, A. CORPORATION OF TEXAS FLUID-OPERATED SWAB Application filed October 20, 1928. Serial No. 313,742.

The invention relates to swabs or plungers for use in raising fluid from wells. It pertains articularly to pressure fluid operated swa s.

In a copending application No. 7 45,998 filed October 22, 1928 by Harold W. Fletcher there is shown an apparatus in which a swab of this character is employed. The plunger operates in a working barrel, or eduction tube, the plunger being raised to the sur' face with its load or liquid by the pressure of air or gas from below the plunger.

It is an object of the present. invention to provide a plunger having a valve adapted to be moved automatically to open position at the upper end of its travel and to be held open while falling, without the necessity of springs or latches thereon.

It is a further object to so shape and proportion the valve that it will not be drawn from its open position without positive contact with a stop member.

Another object is to so construct the swab that it will offer the least possible resistance to travel through the fluid on its downward trip.

It is also desired to form said valve and plunger so that said valve will be held in closed position by the pressure fluid which lifts the plunger and its load ofliquid.

In the drawing, Fig. 1 is a central longitudinal section through a device embodying our inventiom Fig. 2 is a transverse section on the plane 2-2 of Fig. 1. Fig. 3

is a vertical section, somewhat diagrammatic, of the well installation.

The body of the plunger comprises a tubular member 5, the outer surface of which is cylindrical to fit within the eduction tube, as s own. The interior surface 6 decreases in diameter downwardly, the sides converging at 11. v

The two bevels 6 and 11, in conjunction with the valve seat 7 form in effect a Van turi passage through the plunger.

Below said ring is a valve support 12 which is also ring-shaped, but of smaller diameter ries of radial open spaces or inlets 15, through which fluid may pass above the valve. The upper surface of the support inside said posts is recessed to form an inverted frosto conical cavity downwardly tapered at 16 to receive the head of the valve 8. It is to be noted, however, that the lower side 13 of the valve head tapers at a steeper or more acute angle than does the recess 16, thereby providing'an upwardly diverging clearance space shown at 17in the drawing. The valve when in the support fits inside an outer annular rim or head 18 through the lower portion of which are formed small ports'19 to communicate with said space 17.

The ring-shaped support 12 is tapered downwardly on its outer surface and the central opening 20 therethrough is adapted to furnish a guide for the stem 21 of the v ve 8.

Said valve is circular and is tapered i both upward and downward directions from the I valve. There is a slight bevel at 23 to fit the seat 7 when the valve is closed. The stem 21. extends below the supporting ring 12 to contact with a stop member 24 at the lower end of the tube 25.

This swab or plunger is adapted to fit wlth- 'in'an eduction tube 25 set within an outer casingor pipe 26 in a well. The eduction tube is-closed at its upper end except for an outlet passage 27. Its lower end is open at 28 and inlet air openings 29 are formed shghtly above the lower end. The stop member 24 is preferably supportedresiliently by a sprin 30. The casing is sealed about the eduction tube and has an inlet opemng 31 merged the desired distance below the liquid level in thewell.

In the operation of this plunger the valve will be closed and the stem will be resting upon the supporting stop member 24 at the lower end of the educt-ion tube and the plunger will be submerged with a load of liquid above it. The pressure fluid, preferably air \or gas, will be forced into the tube by way ofthe inlet 31 and thecasing' and will enter an, tube below the plunger and will lift the same With its load of liquid to the surface where the liquid will be discharged from the tube. On the upward movement of the plungerthe pressure fluid below the valve, being exerted against a comparatively large area 13 on the lower side of the valve, will tend to retain it closed. weights of the valve and plunger, when their lower surface areas are considered, serves to make it possible for the pressure fluid to hold the valve more firmly upwardly during the lifting operation.

When the fluid is forced from the outlet 27 in the tube adjacent the upper end thereof, the plunger will pass the outlet opening after the liquid is discharged from above it, and the air will then exhaust from below the plunger through the outlet. The liquid and air above the outlet in the tube will be under some pressure, and when the pressure is relieved from below the plunger as just de scribed, the fluid above the plunger will force the valve open, and it will move to its open position as shown in Fig. 1.

-The plunger will then drop in the tube. Itv will strike the liquid and sink therein to its seat on the stop member 24, where the valve will be again closed as previously set out. In dropping through the air and liquid in the tube the plunger will move with high velocity and the air, and later liquid, will pass through the annular space 15 into the interior of the plunger and upwardly relative to the said plunger. This rush of fluid into the plunger past the valve does not raise the valve to close it for the reason that any fluid passing upwardly around the stem into the clearance space 17 is very slight in amount. The'fluid passing the ports 19 exerts a suction effect in the clearance space tending to hold the valve seated? Also-there is little suction effect exerted on the upper end of the valve due to its shape and position below the inlet opening 15 and the level of rim 18. The valve will therefore remain open until the bottom is reached. The shape of the plunger has been adopted to prevent eddying or turbulence in the fluid passing the plunger as it drops. The streamline design leaves no sharp shoulders and the upwardly flaring design of the inner passage 6 .allows free flow of the liquid. The plunger may thus drop Also the comparative rapidly so that there will be little loss of time between the successive strokes of the plunger.

WVhat we claim as new is:

1. A plunger for raising liquid from wells by fluid pressure comprising a tubular cylindrical body having a valve seat, at its lower end, a valve cage including a ring-shaped support below said seat said support having a valve-receiving recess therei'n', a valve in said recess adapted to be moved upwardly to fit said seat, said plunger being constructed so that the dropping of said plungerwill tend to hold said valve in open positionr 2. A plunger for raising liquid from wells by fluid pressure comprising a tubular cylindrical body having a valve seat at its lower end, a valve cage including a ring-shaped support below said seat, said support having a valve-receiving recess therein, a valve in said recess adapted to be moved upwardly to fit said seat, said support having suction openings leading to said recess whereby the dropping of said plunger will tend. to hold said valve in open position.

3. A plunger for raising liquid from wells by fluid pressure comprising a tubular cylindrical body having a valve seat at its lower end, a valve cage including a ring-shaped support below said seat, said support having a valve-receiving recess therein, a valve in said recess adapted to be moved upwardly to fit said seat, said plunger being constructed so that the dropping of said plunger will tend tend to hold said valve in open position, and

a stem on said Valve extending through said ring to guide said valve in its movement.

5. A plunger of the character described having a tubular body, a valve seat at its lower end, a valve below said seat and means actuated by the falling of said plunger tending to hold said valve in a position spaced below said seat.

6. A plunger of the character described comprising a tubular body, a valve seat at the lower end thereof, a valve'cage on said body, a valve below said seat adapted to be supported in open position in said seat, and means to decrease the normal pressure below said valve whereby it will be held in open position when said plunger is dropped downwardly.

7. A plunger of the character described comprising a tubular body, a valve seat at the lower end thereof, a valve cage on said body, valve is retained in open position by the flow a valve below said seat adapted to be supof flu1d upwardly thru said passage.

ported in open position in said cage, and

In testimony whereof, we hereunto afiix means to decrease the normal pressure below our signatures, this the 17th day of October, said valve whereby it will be held in open A. D. 1928.

position when said plunger is dropped downwardly, and means on said valve to contact with a stationary member to close said valve at the lower end of the stroke of said plunger.

8. A plunger of the character describedineluding a tubular cylindrical body, having an upwardly flaring passage therethrough, the lower end of which is flared abruptly outward, a valve support below said body, a valve therein said valve and support tapering downwardly, the upper end of said valve being curved upwardly to an apex, whereby a streamline effect is produced to facilitate theddropping of said plunger rapidly in 9. A device of the character described comprising a body having a downwardly tapering passage therethru, a valve cage carried by said body and having a series of radially disposed inlets to said passage, a

valve support below said inlets of less diameter than the larger diameter of said passage, and a Valve in said support.

10. A device of the character described Comprising a body and a valve support, said body and said support so constructed as to form a passage around said support but thru said body, a valve recess in said support spaced from said passage, and a valve therein adapted to close said passage, said valve being enclosed within said support except for an upwardly streamline end thereon.

11. A device of the character described comprising a body and a valve support, saidbody and said support so constructed as to form a passage around said support but thru said body, and a valve in said support, said body portion having a downwardly tapering passage therethru, a valve cage of less diameter than the top of said passage, a valve in said cage adapted to close said passage, and

. means on said cage whereby the valve is retained in open position by the upward movement of fluid in said passage.

13. A pump plunger adapted to carry a load on its upward stroke, including a body having a passage therethru,/an upwardly closing valve for said passage, and means whereby the valve is retained in open position by the upward fiowof fluid thru said passage.

14. A pump plunger having a tortuous passage therethru, a valve to close said passage and means in said plunger whereby the HAROLD W. FLETCHER.- NORMAN H. RICKER.

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