US2580332A - Pumping apparatus - Google Patents

Description

Dec. 25, 1951 D. H. TEETOR PUMPING APPARATUS Original Filed Nov. 22, 1945 IN VEN TOR.

Patented Dec. 25, 1951 Y UNITED "STATES PATENT *oFFics Original-"application-November 22, 1946, Serial No. 711,582. Divided and this application February 16, 1951, Serial No. 211,366

3 Claims.

- The-invention relates generally to pumping apparatus'for use inwells. and more particularly to such apparatus used in connection with oil wells. v j, I

This application is a divisionor my copending application Serial No. 711,582 filed November 22, 1946. I

Insmall oil wells where the oil has to be re moved by pumping, atype of pumping apparatus frequently employed comprises afcasing extend ing to the bottom of the well and having an intake at its lower end which may comprise a slotted or perforated pipe or a screen to prevent solid material from being drawn into the apparatusor which may be open in case the adjacent earth formation is 'sufliciently tight. Located in the lower end of the casing is a reciprocating pump'operated' by a sucker .rod extendingyup wardlythrough the "casing and mechanically actuated above ground. Such mode of operation is obviously inefiicient.

With wells of this character, the sand or other earth formations at the bottom of the well may become clogged, through, age, to such an extent that the-yield istoo low to warrant further continued operation. The well must therefore either be abandoned or cleaned. Cleaning may beeffected-by forcing water, acids, or other fluid into the sand formation to; remove the obstruct: ing material in thevicinity of the lower end of the casing thus permitting the oil to flow freely;

Heretofore, in so cleaning a well, the pump with its sucker, rod" is removed since noprovision is made for. carrying fluid reversely throughthe reciprocating pump, and a temporary p lpe is ins'erted in, the casing to carry the cleaning fluid under pressure tothe lower endthereof. After thev cleaning hasbeen completed, the temporary pipe is removed and the pump with its sucker rod is reinserted. Obviously such a mode. of cleaning involves'considerable expensaand in many cases'it is questionable whether, when the ,1

Another object is to provide novel pumping 3 apparatus vfor ,a well, through which fluid may q, be reversely conducted to effect cleaning of the intake of the apparatus as well. as the sand formations in the vicinity ,of j the,. intal e A'further object is'to' provide'novelrlpuifiiiiing apparatus for a well, which includes a timenforautomatically reversing the flow in theapparatus at predetermined intervals to remove obstruc tions to flow to and through the intake of th apparatus.

Still another object is to provide novel. ing apparatus for an oil well which mayv be free frowing condition.

Otherobjects and advantages- Willabecome apparent fromthe tollowing description taken in connection ,with the accompanying drawings,

in which the single figure is a vertical sectional.

view, partially diagrammatic, of a pumping apparatusembodying the features of theinvention.

In theusual form oiapparatusutilized .for'

pumping oil, an elongated tubular casing isv provided, extending from i the ground level to the bottom of thewelL-such a casing being shown at"! in the. drawing. ,The upper end of the casing may be closed by a casing head or cover ll whilethelowerend constitutes an intake l2 embedded in thesand or other earth formation from which the oil is obtained and which- .may be open if the adjacent earthqformationis sum? ciently-tight, or whichmay comprise a slotted or perforated pipe or screen. In the ,drawings,

the-intake I2 is shown in the form of Iascreen;

The oil is drawn inwardly through :the intake l2 and forced upwardly to the groundslevel by a pumping unit located inthecasing II), where it may be collectedas in a tank la.

In the mode of operation heretofore commonly employed, such pumping continuescindefinitely, and as a result obstructions to flow will occur in the formation adjacent therintake and, if the intake is-in the form of a pipe orwscreen, ma-w ,teriaLwill collect on the exterior thereof to such an extent thatthe, production of theewellwill be; lowered below the point whereits operation 1 is warranted; At such time, if the well is thought to be capable of continued production, the .well is cleaned as described above and'operation is thereafter continued. The cost of such cleaning is relatively large, however, and if themaximum production of the well is smalhsuchrcleaning is not undertaken andothe well. is abandoned y The present invention provides apparatu:

which maintains the intake and the surrounding formation in a clean free-flowing condition. This result is attained by periodic interruption of the normal flow which causes the collection of obstructions, and eifecting a reverse flow, preferably of the oil itself, through the apparatus so that obstructions to flow inwardly through the formation are cleared away and normal flow can thereafter be resumed. While other liquids than oil could, of course, be employed for the.

reverse flow, oil from the well itself is preferred since no problem of separation is hereby involved. The periodic reversal occurs at sufficiently short intervals to prevent a large accumulation or solidifying of obstructing material and the reverse flow may therefore be maintained for a relatively short period of time, leaving the major portion of time availab'e for productive pumping.

In the form of apparatus shown in the drawing, I provide a pumping unit indicated generally at and comprising a motor l5 anda pump" l6. Both of these are of a reversible type. Thus, the motor may be of a well known type adapted normally serves as an intake through which oil is drawn from the reservoir. The 'oil delivered by the pump during normal flow'is' carried upwardly through a delivery pipe which may extend through the casing head or cover I] and to the tank l3. A packer 2| may be placed in the lower part of the casing H] a short distance above the pump unit, segregating the'intake reservoir from the upper portion of the casing so that a decreased pressure may be induced in the reservoir by the pump to draw oil from the surrounding earth formation inwardly through the The maintenance of a free-flowing condition for the well is better attained if the reversal of flow is effected periodically and at relatively short intervals of time. While the apparatus may of course be controlled manually to attain this result, it is preferably controlled by an automatic timing device indicated diagrammatically at 23'. The timing device 23 includes switch means for effecting a currentreversal at predetermined intervals, the reversal being maintained for the desired period of time. The time of reverse operation may be considerably less than the time during which normal operation occurs so that the major portion of time is spent in productive operation, the flow during such period being maintained at a high rate because of the riddance of any substantial clogging.

I claim:

1. Pumping apparatus for an oil well comprising a casing adapted to extend from the ground level downwardly to the producing. strata of the,

well and having an intake at its lower end in said producing strata, a pump unit comprising a.re.

- versible motor and reversible pump mounted in .mounted in said casing and capable of resist- I ing upward pressurefor confining the reverse. flow from the pump unit to the lower end ofsaid casing, said packer being located closely adjacent the top ofthe pump and above said in.., take whereby the volume of the space below said,

intake I2. The wiring connections for the motor'-' [5, indicated at 22, may extend upwardly to the ground level in the space between the delivery pipe 20 and the wall of the casing for connection with a source of current (not shown) Obviously, continued operation of the pumping motor I5 and pump I6 in the reverse direction from that required to produce the normal flow,

oil from the tank I3 may bedrawn downwardly through the pipe 20 and forced under pressure into the reservoir space below the packer 2!. Such packer being adjacent the lower end of the casing permits a rapid building up of pressure in the reservoir, depending 'upon' the extent of clogging, and the oil will be forced'outwardly through the intake to remove the obstructions therefrom. The reversal of the motor and pump may be easily effected by suitable switching level.

' said casing adjacent the lower end thereof and normally adapted to draw oil inwardly throughsaid intakeand deliverit to the ground level reverse flow therethrough to draw fluid from the ground level and force it outwardly-through said intake to remove obstructions therefrom, and pressure sustaining means comprising a packer packer and between said casing and pump is held to a minimum to permit a rapid build-up of the pressure within said intake on the reverse flow with a minim-umvolume of fluid.

2. Pumping apparatus, for an oil well comprising a casing adapted to extend from the groundlevel to the bottom of the well, and having an intake at its lower end, a pump unit comprising a reversible motor and reversible pump mounted in saidcasing adjacent the lower end thereof and having an inlet adjacent said intake, a delivery pipe extending upwardly within said casing from said pump unit, said pump unit being normally adapted tov draw oil inwardly through said intake and deliver. it upwardly through said delivery... pipe, means for effecting reverse operation of.

said motor and pump for efiecting reverse flow.

said pump and said intake whereby the volume of the space belowsaid packer and between said casing and said pump is held to aminimum to enable the pump to rapidly build up pressure within said space on the reverse flow, said packer being in operative sealing engagement with the casing to withstand upward pressure whereby the] pump 'may 'increase-the'pre ssure of the fluid within said space above that'due to the depth of the-well to force the fluid outwardly from the intake under. high-pressure to removelobstruce 3. Pumping apparatus for an oil well comprising a casing adapted to extend from the ground level to the bottom of the well and having an intake at its lower end, a pump unit comprising a motor and a pump mounted in said casing in the lower end thereof and having means providing communication between the pump and space within the casing between the pump and the intake, a delivery pipe extending upwardly from the pump unit within the casing, said pump unit being normally adapted to draw oil from said intake through said means and deliver it upwardly through said delivery pipe, control means for the pump unit operable to cause the pump unit to draw fluid downwardly through said delivery pipe and to discharge such fluid through said first-mentioned means to the space between the pump unit and the casing, and a packer mounted V in said casing above but adjacent said first-mentioned means and said intake to confine the fluid pumped into said space to the lower portion of said casing adjacent the intake, said packer operatively engaging the casing and constituting a seal against upward pressure, whereby a high pressure may be rapidly builtup within said space with a minimum volume of fluid, with the pressure tending to force the fluid outwardly from the intake to remove obstructions therefrom.

DON H. TEETOR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,138,527 Newman Nov. 26, 1938 2,191,380 Hall Feb. 20, 1940 2,194,740 Coberly Mar. 26, 1940 2,238,597 Page Apr. 15, 1941 2,242,166 Bennett May 13, 1941 2,338,903 Coberly Jan. 11, 1944

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