US1942020A - Oil well pump - Google Patents

Description

Jan. 2, 1934.

N. DORN ET AL OIL WELL PUMP Filed April 10, 1931 Fig. 5

Inventbrs: N.L.Dorn and A. 1

By their Attorney tioned defects.

Patented Jan. 2, 1934 UNITED STATES on. WELL PUMP Norman Lester Born and William Allen Clark, Long Beach, Calif.

Application April 10, 1931. Serial No. 529,022 1 Claim. (01. s09 22) This invention relates to a pump for use in oil wells; in particular the invention consists in packing the ordinary oil well pump with granular metallic material such as lead shot.

It has been found by examination and measurement that many working barrels of oil well pumps are imperfect in that their inside diameters are not uniform, variation as much as 23/1000 of an inch having been observed.

It has also been noted that the inside surfaces of many working barrels are not polished or finished to a high degree. Increased wear of the plunger cups and other working parts result from the use of working barrels with the above-mew The further results of these defects are greatly reduced pumping efiiciency, necessitating the closing down of the well and a replacement of the worn parts.

We have found that the efiiciency of standard oil well pumps can be greatly increased and the rapid wear of the plungers reduced by providing the pump with an aditional packing of lead shot, which will seal up differences in diameter and reduce the roughness of the working barrel.

The various objects and features of our invention will be better and more fully understood from the following detailed description throughout which description reference is had to the accompanying drawing in which Fig. I is a view in elevation partly in section of an oil well pump embodying our invention.

Fig. II is an enlarged longitudinal section of the packing and spool.

Fig. III is a view of construction at end of spool.

The pump provided by our invention is intended to be operated in an ordinary oil well casing (6). The pump generally includes a stationary tubular part called the working barrel (4), a reciprocating part, called the plunger (7) a standing valve (8) at the lower end of the working barrel, and a working valve (9) at the upper end of the plunger. On the plunger shaft of our invention at either end of the section comprising the plunger cups (5), are mounted spools (1) with raised mid-sections (3). The annular spaces between the spools (1) and the barrel (4) we fill with lead shot or similar material (2) The end of the spools are provided with shoulders 10.

ger being by rod or by cable. Assuming that the plunger has just completed its down stroke, the

two valves(8) and (9) will be momentarily at rest with respect to each other and both will be closed. As the up stroke is in progress a partial vacuum is created within the working barrel between the two valves. The standing valve (8) is thereby raised from its seat and oil is drawn into the barrel (4). As the plunger completes its up stroke and the suction effect due to its movement ceases, the standing valve (8) drops F back upon its seat and prevents the oil that has 3 enteredthe barrel from flowing back into the well. On the down stroke the oil within the barrel, unable to escape through the standing valve (8), is put under compression and lifts the upper or working valve (9) from its seat and flows into the tubing above.

The packing (2) interposed between the spool (1) and the wall of the barrel (4) reciprocates with the plunger assembly.

By this action the packing is slightly eroded by its contact with the wall of the barrel (4).

If the barrel is not uniform in diameter throughout its length, a movement of the lead shot will take place to accommodate the changes in diameter. This movement is greatly facili- 0' tated by the shoulders (10) at the ends of the spool. In practice it was found that the width of the shoulders should preferably be slightly less than the diameter of the lead shot used.

By the action of gravity upon the lead shot and due to the shape of the spools (l) with the raised mid-sections (3) the lead shot is kept in constant contact with the wall of the barrel (4). The raised mid-sections (3) also serve to minimize longitudinal motion of the lead shot which might be induced by the reciprocating movement of the plunger.

The advantages obtained by our invention are numerous. As pointed out above, the working barrels of many oil well pumps are not sufiiciently accurate for the work they have to perform. By our invention the minute indentations in the surface of these barrels are rapidly filled in with particles of lead eroded from the packing. The lead thus causes a finely polished surface to be formed. The plunger cups being made of leather or other soft pliable material are no longer dragged over a rough surface which quickly wears them away but are now contacted by a much smoother surface. Often sand enters the pump and scores the surface of the barrel. The lead shot readily fills in these scores.

The variations in the diameter of the barrels of oil well pumps result in leakage past the plunger cups, consequently, the volume of oil ice raised by the pump is reduced. In our invention the lead shot packing forms a continuous seal between the plunger as by its nature it readily conforms to the shape of the chamber in which it is confined.

In the usual oil well pump a great many of the barrels are retired principally because they become scored. Some scoring is the result of the steel members of the plunger or cup assemblies being forced against the walls of the barrel because the plunger becomes wedged in the barrel, this wedging action being caused by the fragments of the leather cups which become jammed between the plunger and the barrel. The shot once in conglomerate form centrally spaces the plunger in the barrel, much in the manner that similar results would be obtained from a bushing of soft material.

By the use of our invention the production of pumping oil wells cannot only be kept from falling off but the production from an oil well may be increased. Pumps embodying our invention have been installed in a number of wells resulting in a substantially increased production. For example, in one well the daily production was increased from 98 barrels of oil per day to 124 barrels of oil per day. This increased production was maintained. It will also be apparent that the number of days per year that a pumping well is in production may readily be increased by our invention, as some of the causes of shutdowns are eliminated.

We have in the above description described our invention in connection with an oil well pump. It should be understood that we reserve the right to use our invention in any other type of apparatus to which it is applicable. We may therefore use our invention as a packing on shafts or may install our invention in water pumps. It should also be understood that whereas we have found that lead shot is the material most suited for our use, we reserve the right to use other granular material which will accomplish the results we have obtained.

We claim as our invention:

An. oil well pump comprising a tubular stationary member, a reciprocating member therein, spools on the reciprocating member, leadshot interposed between said spools and said tubular member, annular shoulders at the end of the spools, said shoulders being of less width than the diameter of said lead shot.

NORMAN LESTER DORN. WILLIAM ALLEN CLARK.

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