US56380A - Improvement in pumps for deep wells - Google Patents

Description

IJNITED STATES PATENT OFFICE,

BENJAMIN CRAWFORD, OF ALLEGHENY, PENNSYLVANIA.

IMPROVEMENT IN PUMPS FOR DEEP WELLS.

Specification forming part of Letters Patent No, 56,380, dated July 17, 1866.

To all whom it may concern:

Be it known that I, BENJAMIN CRAWFORD, of the city of Allegheny, in the county of Allegheny and State of Pennsylvania, have i11- vcnted a new and useful Improvement in Pumps for Artesian lVells and I do hereby declare the following to be a full, clear, and exact description thereof, reference being bad to the accompanying drawings, forming part of this specification, in which- Figure l is an external elevation of my improved pump. Fig. 2 is a vertical section of the pump, the plane of section being at right angles to the plane of elevation of Fig. I.

In both figures like letters of reference are employed to designate similar parts.

The pump, which I am about to describe being designed for use in Artesian wells, the tubing above the working valves is made of any required length.

In Artesian wells, especially in those from which petroleum is obtained, great inconvenience is experienced from the presence of gas in the well, which exerts more or less upward pressure, and frequently interferes materially with the pumping of the oil and water. Owing to the long column of water or oil in the rising-pipe of the pump above the valves, there is so powerful a downward pressure that the gas cannot rise freely to the top of the well, and, with a pump of ordinary construction, will fill the working barrel of the pump between the two valves, and thus effectually stop the operation of raising the oil and water. It will also raise the lower valve during the downward stroke of the pump-piston, and allow the oil and water to flow back again into the well. Thus, whenever the pressure of gas in the well is not sufficient to force the oil and water up through the rising-pipe to the top of the well and cause it to flow without pumpin g, it will obstruct the action of the pump, and often render it entirely inoperative, unless it can be got rid of without being permitted to pass through the column of liquid in the well-tube above the pump-valves.

My invention is designed to overcome these difficulties and secure the proper action of the pump, notwithstanding the upward pressure To enable others skilled in the art to make use of my invention, I will proceed to describe the construction and operation of myimproved pump, and in so doing I will first explain those parts which relate to the raising of the oil and water and the escape of the gas, and then show how the several parts are operated.

In the drawings, a is the tubing of the well or risingpipe, through which the oil and water are raised. The flow-pipeb, which is curved at 0, so as to form a trap to prevent any gas from passing out with the oil and water, is placed at a lower level than the branch gaspipe (I, which carries off the gas as it escapes through apertures n in the top of the gas-pipe 6, above the level of the oil and water in the tube a. The gas from the well may be conducted by the branch pipe (1 to a gas-holder and used for illuminating purposes or as fuel under the boilers of the steam-engine. Thelowest section of the well-tubing a is screwed into the upper end of the pump-chamber or Working barrel f.

The gas-pipe 0 extends from the top of the well-tubing a to the box 9 of the check-valve h, being screwed at its lower extremity into the check-valve box g, which is inserted into the lower end of the last section of tubing a, just above the working chamber of the pump. The check-valve h rests on a valve-seat, t', which is screwed into the check-valve box g. A short piece of gas-pipe, j, of such diameter as to work closely (like a telescope-slide) inside the main gas-pipe 0, passes longitudinally through the center of the check-valve h, and also through the working valve 70, and is fastened to the top ring of the working-valve box I, thus serving as a guide to the check-valve h and working valve it, both of which slide on it. The working valve it rests, when closed, on a valve-seat, m, screwed up into the working-valve box I, and incloses the leatherpacking-rin g 0. The working-valve box or piston l is moved up and down in its stroke by means of two rods, 19 p, screwed into it and extending upward through the check-valve box g and outside of the gas-pipe c, to the top of the well.

At the lower extremity of the pump-chamber f is seated the bottom valve, q, in a suitable valve-box, 1". On top of the valve q is a tubular projection, s, forming a step or seat for the end of the rod t, which rod extends upward in the center of the well through the gastubes 0 and j, leaving sufficient space around it in these tubes for the free passage of the gas.

The mechanism by which the several parts of the pump are operated, as shown in Fig. 1,

is constructed as follows: The walking-beam w, by which the stroke of the piston-rods p is effected, is supported by and vibrates on a standard, u. It is connected to one extremity of a link, 0, the other extremity of which is connected with the free end of the lifting-arm m, the center of the link being pivoted to the head of the piston-rods p p. The top of the rod 15, by which the bottom valve, q, is shut down,is pivoted to a horizontal lever, 31, which has its fulcrum in the standard 2 at i. The lifting-arm no is also pivoted to the standard 2 at i. From the lifting-arm m hangs a pendant, (1, consisting of two parallel rods connected by a pin, 0, at their lower end, or a single rod with a loop, the pin 0 resting against the face of a cam, a, so as at the proper time to enter a notch or recess, a, in the cam, and either raise or depress it, as the lifting-arm m is raised or lowered by the vibration of the walking-beam w. The lever r attached to the lower valve-rod, t, rests on the top of the cam a, so that when on the upstroke of the pistonrods 12 p the lifting-arm 0c is raised and the cam to also raised, the lever y is forced upward, elevating the valve-rod t; and as soon as the downstroke of the piston-rods p 19 commences the cam a is turned down, which lowers the lever r or allows it to fall, when the valverod 13 descends by its own weight on the lower valve, q, and closes it. The cam a has its center of motion or hearing in a small standard, I).

It is important that the device for raising and lowering the valve-rod it should be so arranged in the manner described, or otherwise, as that the rod 75 shall be raised as soon as the upstroke of the piston of the pump commences, and be sustained until the downstroke begins, and that it should be then immediately re leased and allowed to fall on the valve q.

Having thus described the construction of my improved pump, I will proceed to describe the effect produced by its operation.

On the upstroke of the piston l the lever 31 is raised, as before stated, by the cam a, and thus the rod t is elevated more or less, according to the shape or stroke of the cam, so as to leave the lower valve, q, free to rise, which it will do, not by atmospheric pressure in the ordinary way, but by the upward force of the gas from the well below.

In my pump, constructed as shown in the drawings, the gas-pipes being open at both ends, the raisingof the piston ldoes not create a vacuum, which is unnecessary for the reason just stated; but, if desired, a valve may be placed on the upper end of the gas-pipe, so as to make the pump work by atmospheric pressure, and the apertures 12 dispensed with.

On the rising of the piston l the gas rushes through the valve q, and finds a free vent through the gas-pipes c and j, and the chamber of the pump, between the valves 70 and q, is filled with oil, or oil and water, from the well below, and at the same time the contents of the space between the working valve is and check-valve h are lifted up by the valve 70, and forced upward above the check-valve h.

When the downstroke of the piston 1 begins the cam a turns to allow the rod tto drop upon and close the lower valve, q. Should the weight of the rod 15 prove insufficient to counteract the forcepf the upward flow of gas and oil, the rod 25 may be weighted by means of a poise suspended on an extension of the lever y. The piston and working valve 70 then descend, and the check-valve h is closed by the weight of the superincumbent column of oil and water in the well-tube a, which is thus prevented from pressing down on the valve 70 or forcing the oil and water up the gas-pipes c andj.

By the descent of the piston Z the contents of the pump-chamber between the valves 76 and q pass above the working valve k, ready to be lifted above the check-valve on the next upstroke of the piston. I

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The detached rod t, in combination with the lower valve, q, for the purpose of keeping the lower valve closed on the downstroke of the piston.

2. The combination and arrangement of the lever y and valve-rod t with the cam a and pendant d, for raising and lowering the valverod t, to relier'e the lower valve, q,.ot' its pressure when the upstroke begins, and hold it down on the commencement of the downstroke, substantially as described.

3. The combination of the check-valve hand gas-pipej c with the working valve of a pump, constructed and arranged substantially as and for the purposes hereinbefore described.

4. In its arrangement with the devices described in the third claim, the trap c in the flow-pipe, to prevent the passage of gas in that direction, substantially as described.

In testimony whereof I, the said BENJAMIN CRAWFORD, have hereunto set my hand.

BENJ. CRAWFORD.

Witnesses W. BAKEWELL, ALLAN G. BAKEWELL.

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