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US3186354A - Oil well pump - Google Patents

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US3186354A
US3186354A US266634A US26663463A US3186354A US 3186354 A US3186354 A US 3186354A US 266634 A US266634 A US 266634A US 26663463 A US26663463 A US 26663463A US 3186354 A US3186354 A US 3186354A
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valve
barrel
head
sleeve
pump
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US266634A
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Earl R Mahoney
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Reynolds Oil Well Pumps Inc
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Reynolds Oil Well Pumps Inc
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B47/00Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps
    • F04B47/02Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps the driving mechanisms being situated at ground level
    • F04B47/04Pumps or pumping installations specially adapted for raising fluids from great depths, e.g. well pumps the driving mechanisms being situated at ground level the driving means incorporating fluid means

Definitions

  • the present invention relates to improvements in traveling valve structures used in reciprocating oil well pumps of the type disclosed in United States Patent 2,933,050, issued on April 19, 1960, to Leland S. Crowl and Alvin M. Markwell and assigned to the assignee of the present application.
  • each sleeve cooperates with the next lower adjacent head on the upstroke by the sucker rod pump to form a piston for lifting a column of oil above the standing valve
  • each sleeve cooperates with the up er adjacent head to form a traveling valve for movement of the piston and traveling valve assembly downwardly through oil in the pump, while the oil is prevented from downward movement by the usual standing valve located below the piston and traveling valve assembly.
  • the present invention is an oil well pump which incorporates certain improvements in the Crowl et al. pump which effect a better and more durable seal against by pass of oil in the production tubing during upstroke of the pump, yet which retains all of the advantageous features of the Crowl et al. pump and permits such pump to be easily and economically adapted for use in wells of different depths.
  • the improvement of the present invention may be summarily described as the incorporation in the Crowl et al.
  • the invention comprises a tubular working barrel having a standing valve positioned in the lower end thereof; a string of sucker rods extending downwardly into the working barrel and reciprocated by a suitable driving mechanism at the surface; a cylindrically shaped head slidingly positioned in the working barrel and having at least one longitudinal fluid bypass groove in the outer periphery thereof extending from one end of the head to the other end thereof with the depth of the groove being less adjacent the upper end of the head than at the lower end of the head; a first tubular sleeve slidingly fitted in the working barrel above the cylindrically shaped head and having a wall thickness greater than the depth of the groove at the upper end of the head, the adjacent ends of said head and said first tubular sleeve being complementary in shape to form a seal when the head and sleeve contact each other at their adjacent ends; a second tubular sleeve slidingly fitted in the barrel above said first tubular sleeve and sealingly engaging at its outer peripher
  • the cylindrically shaped head which is slidingly positioned in the working barrel of the pump is provided with an axial bore which is threaded at each of its ends.
  • the head is thus adapted to be connected both to the rod means connecting it to the uppermost or second sleeve in the manner described, and also is adapted to be connected through suitable connecting rods to additional head members positioned lower in the Working barrel.
  • the provision of the ball valve in a valve cage carried at the upper end of the uppermost sleeve of the pump assembly of the present invention permits a positive seal to be established by the downward biasing of the ball valve onto its seat during the upstroke of the pump. This allowsthe traveling valve or valves formed by the lowermost sleeves and cooperating heads to be relieved of a substantial portion of their fluid load during the upstroke of the pump and thus avoids leakage and bypassing of oil past this traveling valve as the pump becomes advanced in its operating life.
  • a further object of the present invention is to provide a sucker rod pump having an improved traveling valve assembly therein which permits less fiuid bypass of the valve during the upstroke of the pump.
  • An additional object of the present invention is to provide a sucker rod pump which may be easily and economically adapted for use in wells of varying depths.
  • a further object of the invention is to provide a sucker rod pump structure wherein the operating depth of the pump may be easily increased by adding a minimum number of Working parts to the pump.
  • FIGURES 1 and 1A considered conjunctively are vertical sectional views through the upper and lower ends of a pump constructed in accordance with this invention.
  • FIGURE 1 illustrates the portion of the pump located above the standing valve of the pump and
  • FIGURE 1A is the lower portion of the pump containing the standing valve and a suitable anchor or shoe for seating the pump in the lower end of the well tubing in a conventional manner.
  • FIGURE 2 is an exploded view of the traveling valve assembly of a pump constructed in accordance with the present invention.
  • FIGURE 3 is a view in section as taken along line 33 of FIGURE 1.
  • reference character designates an elongated tubular Working barrel of the type conventionally employed in sucker rod type oil well pumps.
  • the pump may be of any suitable type, but is preferably of the type which is inserted in the lower portion of an oil well tubing and which may be removed separately from the tubing.
  • the working barrel 10 is of substantial length and has a suitable guide structure (not shown) in its upper end to slidingly receive the lower end portion of a string of sucker rods extending from thesurface of the well.
  • the lower end of the sucker rod string (not seen) is connected into the upper connecting rod 12 of the pump for operating the pump, as will be more fully hereinafter set forth.
  • the lower end of the working barrel 10 is internally threaded for connection with a tubular valve cage 14 having the usual spider 16 in the upper portion thereof to limit the upward movement of a ball type standing valve 18.
  • Apertures 26 extend through the spider 16 in the usual manner.
  • the lower end of the valve cage 14 is internally threaded to receive the upper end of a suitably constructed anchor or shoe 22;.
  • a seat 24 for the valve 13 may be secured between opposed shoulders in the cage 14 and the anchor 22.
  • the anchor 22 is utilized to seat the pump in a complementary shaped shoe secured on the lower end of the Well tubing in a conventional manner, whereby the pump will be anchored in the lower end of the tubing by friction, yet the pump may be pulled upwardly through the tubing when a substantial force is imposed on the sucker rod string.
  • the piston and traveling valve assembly is positioned in the working barrel Iii above the standing valve 18 and is slidably disposed in the working barrel to lift oil entering the working barrel through the anchor 22, valve seat 24 and'valve cage 14.
  • the pisremaining element of the basic assembly is a tubular sleeve 38 which is slidingly positioned in the working barrel 10 around the connecting rod 35?, and which is of lesser length than the connecting rod 30 so that the sleeve 33 cannot be contacted by the connecting means 32 and the head 28 simultaneously.
  • cylindrical head 28 is internally threaded or otherwise suitably adapted for connection to another of the connecting rods 3% so that a series of heads 28 may be interconnected to each other with their pull rods each passing through a tubular sleeve identical to the sleeve 33, and in each case having a length which is less than the distance between each pair of interconnected heads 28 whereby the heads 28 will be moved in the working barrel it) relative to the sleeve 38 when the direction of movement of the heads is reversed.
  • the head 28 is generally cylindrical in configuration and is characterized by an outside diameter which conforms substantially to the inside diameter of the working barrel it to provide a sliding fit of the head in the working barrel.
  • a series of circumferentially spaced grooves 46 are cut longitudinally in the periphery of the head 28 to permit oil to flow around the head during the downstroke of the pump in the manner hereinafter described in greater detail.
  • Each of the grooves 40 is of varying depth in a radial sense with the depth of the groove being greaterat the lower end of the head 2% than at the upper end thereof. The varying depths of the grooves 40 is most clearly illustrated in FIGURE 1 of the drawings.
  • An axial bore 42 is provided through the head 28 and the bore is threaded at its lower end to receive the upper end of a connecting rod 30 when it is desired to connect a plurality of heads and connecting rods in tandem or series in the working barrel 1%.
  • the lower end of each of the connecting rods 30 is passed into the upper end of the bore 42 through the head 28 and is secured in the head by a suitable pin 44 which is passed through a radial aperture in the head and engages a mating aperture formed in the lower end of the connecting rod.
  • the pin 44 serves to prevent longitudinal movement of the head 28 on the connecting rod 36.
  • the head 28 is provided with a tapered seating surface 46 which is constructed of hardened metal and is configured to mate with the oppositely tapered lower end 48 of the sleeve. It will be understood that upward longitudinal movement of the connecting rod 30 and its associated head 2% relative to the sleeve 38 will bring the seating surface as at the upper end of the head into contact with the mating sunface on the lower end 4 3 of the sleeve. A seal will thus be etiected preventing the downward flow of oil in the working barrel past the head 23 as the pump moves in its updeeper at their ends adjacent the upper end of the connecting member 32 than at their lower ends.
  • the depth of the grooves 52 at their lower ends is greater than the thickness of the lower sleeve 33 so that when the connecting member 32 is seated upon the upper end of the lower sleeve 38, fluid may pass from the grooves 52 into the bore of the lower sleeve.
  • a series of radial apertures 54 corresponding in number of the number of the longitudinal grooves 52 is provided for the purpose of placing the longitudinal grooves 52 in communication with the axial bore 53 through the connecting member 32.
  • the connecting member 32 is alternately moved into and out of contact with the upper end of the lower sleeve 33.
  • the lower end 56 of the connecting member 32 is preferably tapered to mate with the complementary tapered upper end 58 of the lower sleeve 38.
  • the ball type standing valve 36 comprises a valve cage 62 which is most clearly illustrated in FIGURE 2 of the drawings.
  • the valve cage 62 has an axial bore 64 extending upwardly thereinto from its lower end and is also provided with a second axial bore which extends into the valve cage from the upper end thereof.
  • valve cage 62 is longitudinally grooved with a plurality of circumferentially spaced grooves 65 which extend from the upper end of the cage over a major portion of the longitudinal length thereof.
  • the external periphery of the lower portion of the cage 62 is not, however, grooved and provides a sliding, sealing fit of the valve cage with the internal wall of the working barrel 10.
  • a suitable annular valve seat 7@ is press fitted or otherwise suitably secured in the axial bore 64 at the lower end of the valve cage 62 and is retained therein by the fitting 60.
  • a spherical valve member 72 is positioned in the bore 64 above the annular valve seat 70 and is dimensioned to permit free floating or reciprocating movement in the axial bore 64 of the valve cage 62 as oil passes through the cage.
  • the lower sleeve 38 will tend to remain stationary in the working barrel 10 due to the friction fit of the sleeve in the working barrel.
  • the ball type standing valve 36 is opened by movement of the spherical valve member 72 ofl the annular seat 70 and the sleeve 34 and valve cage 62 commence to move downwardly through the column of oil standing above the standing valve 18 in the lower end of the working barrel 10.
  • the head 28, connecting rod 30 and upper sleeve 34 will move downward relative to the lower sleeve 38 to unseat the head 28 from the tapered lower end portion 48 of the lower sleeve.
  • the standing valve 18 will seat upon the seat 24 when the downstroke of the pump is begun due to the increased pressure in the lower end portion of the working barrel 10 relative to the pressure of the fluid standing in the well and in the anchor 22.
  • the downward stroke of the pump provides, in effect, a displacement of oil from the lower portion to the upper portion of the working barrel it above the piston and traveling valve assembly.
  • the direction of movement of the head 24, connecting rod 30 and sleeve 34 is reversed.
  • the floating lower sleeve 38 will, however, tend to remain stationary in the working barrel 1%.
  • the spherical valve member 72 of the ball type standing valve 35 will immediately seat upon its annular seat 70 and prevent oil from flowing downwardly through the upper sleeve 34 and connecting member 32 into the floating lower sleeve 38.
  • the oil which is contained in the sleeves 34 and 38 below the ball type standing valve 36 will, however, flow downwardly past the head 28 and no pumping action will take place.
  • the head 28 after the head 28 has been moved upwardly a relatively short distance, the head will contact the lower end 48 of the lower sleeve 38 and the lower sleeve will be seated upon the seat 46 of the head to again provide a pumping action in the manner previously described.
  • the seal which is established between the seating surface 46 on the head 28 and the lower end 48 of the floating sleeve 38 will be subjected to less hydrostatic head than it has previously supported as a result of the preliminary closing of the standing valve 36 to isolate'the floating sleeve 38 and head 28 from the column of oil above the upper standing valve.
  • FIGURES l and 1A of the drawings When it is desired to lift a longer and heavier column of fluid with the pump of the invention, the plunger and traveling valve assembly illustrated in FIGURES l and 1A of the drawings may be duplicated by the connection of additional connecting rods 30 and heads 28 in series or tandem to the connecting rod and had shown in the drawings. It is also within the scope of the invention to include additional connecting rods, floating sleeves, heads and ball type standing valve assemblies which are connected above the upper standing valve 36 shown in the drawings.
  • the arrangement illustrated in the drawings of the present application may be substantially duplicated by the addition of one or more of each of the elements there shown or, under some circumstances, it may be desirable merely to incorporate in the assembly additional connecting rods 39 and heads 28 which are connected below the single connecting rod and head shown in the drawings of this application and which function to extend the operating depth of the pump over that which is obtainable with the arrangement illustrated.
  • the desirable washing action which is characteristic of the heads 23 by virtue of their grooved outer peripheral surfaces is retained and, in iiact, is enhanced by the use of a connecting member of similar construction for connecting the head to the upper sleeve which carries the ball type standing valve.
  • the use of the elongated upper sleeve for supporting the cage which houses the ball type standing valve and for connecting the ball .type standing valve assembly through the connecting member to the connecting rod which is secured to the upper end of the head provides a substantial increase in the integrity of the seal which is afforded between the standing valve members and the internal wall of the working barrel.
  • the sliding fit of the elongated upper sleeve which carries the ball type standing valve cage assures that there can be little or no leakage around the plunger and traveling valve assembly during the upstroke of the pump.
  • This sleeve thus functions to complement the sealing action afiiorded .by the lower floating sleeve provided in the Crowl pump, and further improves the chiciency of the Crowl pump and its eflective service life.
  • An oil well pump comprising:
  • a head positioned in said barrel below said tubular sleeve and adapted to seal the lower end of said tubular sleeve, said head having fluid deflecting grooves therein dimensioned and configured to deflect oil moving upwardly past said head radially outwardly against said barrel;
  • valve cage slidingly positioned in said barrel above said tubular sleeve and sealingly engaging at its outer periphery the internal walls of said barrel;
  • valve member above said valve seat in said valve cage and movable in said cage into and out of seating engagement with said valve seat;
  • valve cage means connected to said valve cage and cooperating with said head to reciprocate said sleeve in said barrel in a shorter reciprocating stroke than the reciprocating stroke of said valve cage and head during operation of the pump, said means connected to said valve cage including fluid passageway means for permitting fluid flowing upwardly from said tubular sleeve to pass through said valve seat during the upward movement of said rod, valve cage and head.
  • An oil well pump comprising:
  • valve cage secured to the upper end of said first tubular sleeve and having apertures therethrough to place the bore of said first tubular sleeve in communication with the bore of said tubular barrel;
  • valve member above said valve seat in said valve cage and movable in said cage into and out of seating engagement with said valve seat;
  • a cylindrically shaped head slidingly positioned in. said barrel and having at least one longitudinal groove in the outer periphery thereof extending from end to end thereof, with the depth of the groove being less at the upper end of the head than at the lower end of the head;
  • valve cage secured to the upper end of said second tubular sleeve and having apertures therethrough to place the bore of said second tubular sleeve in communication with the bore of said working barrel above said second tubular sleeve, said valve cage being adapted for connection to the lower end of the sucker rod string of the pump;
  • a pump as claimed in claim 3 wherein said head is provided with an axial bore extending therethrough and threaded at its lower end for connection to a downwardly extending rod.
  • a pump as claimed in claim 3 wherein the hollow, radially apertured upper end portion of said rod means comprises an axially bored, generally cylindrical member connected to said second sleeve with its bore communicating with the bore of said second sleeve and having at least one longitudinal groove in the outer periphery thereof extending from end to end thereof, with the depth of the groove being less adjacent the upper end of the head than at the lower end of the head, and said cylindrical member further having a radial aperture placing the axial bore of said cylindrical member in communication with each longitudinal groove.

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Description

June 1, 1965 E. R. MAHONEY 3,186,354
OIL WELL PUMP Filed March 20, 1963 IN VENTOR Ema. A MAHOME-Y I BY United States Patent 3,186,354 OIL WELL PUMP Earl R. Mahoney, Oklahoma City, Okla, assignor to Reynolds Gil Well Pumps, Inc., Oklahoma City, Okla, a corporation of Delaware Filed Mar. 20, 1963, Ser. No. 266,634 6 Claims. (Cl. 103-179) This invention relates to improvements in reciprocating pumps, and more particularly, but not by way of limitation, to improvements in pumps used in the lower portion of an oil well to remove oil from the well. Yet more specifically, the present invention relates to improvements in traveling valve structures used in reciprocating oil well pumps of the type disclosed in United States Patent 2,933,050, issued on April 19, 1960, to Leland S. Crowl and Alvin M. Markwell and assigned to the assignee of the present application.
In the Crowl et a]. patent to which reference has been made, a useful reciprocating pump specially adapted for use in oil wells is disclosed and is described as facilitating the use of the piston and traveling valve assembly of the pump at substantially any depth without the requirement for replacement or changeover to a piston and traveling valve of different characteristics. The Crowl et al. piston and traveling valve assembly comprises a series of vertically spaced heads with a sleeve disposed between each pair of heads. During operation of the pump, each sleeve cooperates with the next lower adjacent head on the upstroke by the sucker rod pump to form a piston for lifting a column of oil above the standing valve On the downstroke, each sleeve cooperates with the up er adjacent head to form a traveling valve for movement of the piston and traveling valve assembly downwardly through oil in the pump, while the oil is prevented from downward movement by the usual standing valve located below the piston and traveling valve assembly.
Although the pump described in the Crowl et al. patent has worked well and has accomplished its objects of providing a sucker rod pump which may be easily and economically adapted for use in wells of different depths, and which require a minimum number of working parts in the pump, use of the Crowl et al. pump has indicated it to be subject to occasional malfunctioning, or at least, inefficient functioning, as a result of the washing out, grooving or destruction of the valve seat which is formed on each of the vertically spaced heads, and which cooperates with the sleeve immediately above the head during the upstroke of the pump to prevent oil from bypassing the head rather than being lifted upwardly in the production tubing. The propensity of the vertically spaced heads to bypass oil rather than making a durable and long lasting fiuid type seal against the lower end of the respective sleeve with which each head cooperates is largely due to the fact that the column of oil standing above the head acts downwardly upon the head and tends to force the head away from the sleeve and destroy the integrity of the seal between these elements.
The present invention is an oil well pump which incorporates certain improvements in the Crowl et al. pump which effect a better and more durable seal against by pass of oil in the production tubing during upstroke of the pump, yet which retains all of the advantageous features of the Crowl et al. pump and permits such pump to be easily and economically adapted for use in wells of different depths. The improvement of the present invention may be summarily described as the incorporation in the Crowl et al. pump of a ball type standing valve above the vertically spaced heads and intervening sleeve structures of the Crowl pump, which ball type standing valve is biased by the downwardly acting pressure of the Patented June 1, 1965 column of oil standing thereabove in the production tubing into firm seating contact with a seat which is provided below the ball valve member.
In terms of the overall pump structure of the present invention, the invention comprises a tubular working barrel having a standing valve positioned in the lower end thereof; a string of sucker rods extending downwardly into the working barrel and reciprocated by a suitable driving mechanism at the surface; a cylindrically shaped head slidingly positioned in the working barrel and having at least one longitudinal fluid bypass groove in the outer periphery thereof extending from one end of the head to the other end thereof with the depth of the groove being less adjacent the upper end of the head than at the lower end of the head; a first tubular sleeve slidingly fitted in the working barrel above the cylindrically shaped head and having a wall thickness greater than the depth of the groove at the upper end of the head, the adjacent ends of said head and said first tubular sleeve being complementary in shape to form a seal when the head and sleeve contact each other at their adjacent ends; a second tubular sleeve slidingly fitted in the barrel above said first tubular sleeve and sealingly engaging at its outer periphery the internal wall of said barrel; a valve cage secured to the upper end of said second tubular sleeve and having apertures therethrough to place the bore of said second 7 tubular sleeve in communication with the bore of the said working barrel above the second tubular sleeve, the valve cage being adapted for connection to the lower end of the sucker rod string of the pump; a valve seat in the valve cage below the apertures through the valve cage; a valve member above said valve seat in said valve cage and movable in the cage into and out of seating engagement with the valve seat therein; and rod means of longer length than the said first sleeve extending through the bore of the first sleeve and interconnecting the cylindrically shaped head and the second sleeve, said rod means having a hollow, radially apertured upper end portion connected to the lower end of said second sleeve for passing fluid from the bore of the second sleeve to the bore of the first sleeve.
The cylindrically shaped head which is slidingly positioned in the working barrel of the pump is provided with an axial bore which is threaded at each of its ends. The head is thus adapted to be connected both to the rod means connecting it to the uppermost or second sleeve in the manner described, and also is adapted to be connected through suitable connecting rods to additional head members positioned lower in the Working barrel. By virtue of this arrangement, the pump may be easily and economically adapted for use in wells of greatly differing depths. The latter concept is fully disclosed and described in the Crowl et al. patent and the teachings of that patent are incorporated herein by reference.
The provision of the ball valve in a valve cage carried at the upper end of the uppermost sleeve of the pump assembly of the present invention permits a positive seal to be established by the downward biasing of the ball valve onto its seat during the upstroke of the pump. This allowsthe traveling valve or valves formed by the lowermost sleeves and cooperating heads to be relieved of a substantial portion of their fluid load during the upstroke of the pump and thus avoids leakage and bypassing of oil past this traveling valve as the pump becomes advanced in its operating life.
From the foregoing description of the invention, it will have become apparent that it is an important object of the present invention to provide a sucker rod pump for use in oil wells and the like which is characterized by a longer and more trouble free operating life than has been characteristic of pumps generally similar to the type of pump here under consideration which have previously been used.
A further object of the present invention is to provide a sucker rod pump having an improved traveling valve assembly therein which permits less fiuid bypass of the valve during the upstroke of the pump.
An additional object of the present invention is to provide a sucker rod pump which may be easily and economically adapted for use in wells of varying depths.
A further object of the invention is to provide a sucker rod pump structure wherein the operating depth of the pump may be easily increased by adding a minimum number of Working parts to the pump.
Other objects and advantages of the invention will become apparent as the following detailed disclosure of the invention is read in conjunction with a perusal of the accompanying drawings which illustrate my invention.
In the drawings:
FIGURES 1 and 1A considered conjunctively are vertical sectional views through the upper and lower ends of a pump constructed in accordance with this invention. FIGURE 1 illustrates the portion of the pump located above the standing valve of the pump and FIGURE 1A is the lower portion of the pump containing the standing valve and a suitable anchor or shoe for seating the pump in the lower end of the well tubing in a conventional manner.
FIGURE 2 is an exploded view of the traveling valve assembly of a pump constructed in accordance with the present invention.
FIGURE 3 is a view in section as taken along line 33 of FIGURE 1.
Referring now to the drawings in detail, and particularly, to FIGURE 1, reference character designates an elongated tubular Working barrel of the type conventionally employed in sucker rod type oil well pumps. The pump may be of any suitable type, but is preferably of the type which is inserted in the lower portion of an oil well tubing and which may be removed separately from the tubing. The working barrel 10 is of substantial length and has a suitable guide structure (not shown) in its upper end to slidingly receive the lower end portion of a string of sucker rods extending from thesurface of the well. The lower end of the sucker rod string (not seen) is connected into the upper connecting rod 12 of the pump for operating the pump, as will be more fully hereinafter set forth.
The lower end of the working barrel 10 is internally threaded for connection with a tubular valve cage 14 having the usual spider 16 in the upper portion thereof to limit the upward movement of a ball type standing valve 18. Apertures 26 extend through the spider 16 in the usual manner. The lower end of the valve cage 14is internally threaded to receive the upper end of a suitably constructed anchor or shoe 22;. A seat 24 for the valve 13 may be secured between opposed shoulders in the cage 14 and the anchor 22. The anchor 22 is utilized to seat the pump in a complementary shaped shoe secured on the lower end of the Well tubing in a conventional manner, whereby the pump will be anchored in the lower end of the tubing by friction, yet the pump may be pulled upwardly through the tubing when a substantial force is imposed on the sucker rod string.
The piston and traveling valve assembly is positioned in the working barrel Iii above the standing valve 18 and is slidably disposed in the working barrel to lift oil entering the working barrel through the anchor 22, valve seat 24 and'valve cage 14. Generally speaking, the pisremaining element of the basic assembly is a tubular sleeve 38 which is slidingly positioned in the working barrel 10 around the connecting rod 35?, and which is of lesser length than the connecting rod 30 so that the sleeve 33 cannot be contacted by the connecting means 32 and the head 28 simultaneously.
Before proceeding to a more detailed and specific description of the elements thus broadly described, it will be noted. that the cylindrical head 28 is internally threaded or otherwise suitably adapted for connection to another of the connecting rods 3% so that a series of heads 28 may be interconnected to each other with their pull rods each passing through a tubular sleeve identical to the sleeve 33, and in each case having a length which is less than the distance between each pair of interconnected heads 28 whereby the heads 28 will be moved in the working barrel it) relative to the sleeve 38 when the direction of movement of the heads is reversed. The appearance of the pump when a plurality of the heads 28 are interconnected by a plurality of connecting rods 3% passing through a plurality of tubular sleeves 3% is fully illus trated and described in the Crowl et al. patent to which reference has heretofore been made.
Referring next to the specific construction of the several elements of the piston and traveling valve assembly of the present invention, the head 28 is generally cylindrical in configuration and is characterized by an outside diameter which conforms substantially to the inside diameter of the working barrel it to provide a sliding fit of the head in the working barrel. A series of circumferentially spaced grooves 46 are cut longitudinally in the periphery of the head 28 to permit oil to flow around the head during the downstroke of the pump in the manner hereinafter described in greater detail. Each of the grooves 40 is of varying depth in a radial sense with the depth of the groove being greaterat the lower end of the head 2% than at the upper end thereof. The varying depths of the grooves 40 is most clearly illustrated in FIGURE 1 of the drawings. This construction results in the oil flowing upwardly through the grooves 40 being deflected outwardly against the internal wall of the working barrel It? to provide a Washing action against the working barrel 1% at the upper end of the head 28 during downward movement of the piston and traveling valve assembly.
An axial bore 42 is provided through the head 28 and the bore is threaded at its lower end to receive the upper end of a connecting rod 30 when it is desired to connect a plurality of heads and connecting rods in tandem or series in the working barrel 1%. The lower end of each of the connecting rods 30 is passed into the upper end of the bore 42 through the head 28 and is secured in the head by a suitable pin 44 which is passed through a radial aperture in the head and engages a mating aperture formed in the lower end of the connecting rod. The pin 44 serves to prevent longitudinal movement of the head 28 on the connecting rod 36.
At its upper end, the head 28 is provided with a tapered seating surface 46 which is constructed of hardened metal and is configured to mate with the oppositely tapered lower end 48 of the sleeve It will be understood that upward longitudinal movement of the connecting rod 30 and its associated head 2% relative to the sleeve 38 will bring the seating surface as at the upper end of the head into contact with the mating sunface on the lower end 4 3 of the sleeve. A seal will thus be etiected preventing the downward flow of oil in the working barrel past the head 23 as the pump moves in its updeeper at their ends adjacent the upper end of the connecting member 32 than at their lower ends. The depth of the grooves 52 at their lower ends is greater than the thickness of the lower sleeve 33 so that when the connecting member 32 is seated upon the upper end of the lower sleeve 38, fluid may pass from the grooves 52 into the bore of the lower sleeve. A series of radial apertures 54 corresponding in number of the number of the longitudinal grooves 52 is provided for the purpose of placing the longitudinal grooves 52 in communication with the axial bore 53 through the connecting member 32. Thus, when the connecting member 32 abuts the lower sleeve 38, fluid may pass from the bore of the upper sleeve 34 through the bore 56 in the connecting member 32,
through the radial apertures 54, through the longitudinal grooves 52 and into the axial bore through the lower sleeve. It will be apparent that, when the sleeve 34 is reciprocated in the working barrel 10, the connecting member 32 is alternately moved into and out of contact with the upper end of the lower sleeve 33. The lower end 56 of the connecting member 32 is preferably tapered to mate with the complementary tapered upper end 58 of the lower sleeve 38.
At its upper end, the upper sleeve 34 is connected through a suitable coupling or fitting 6t to the ball type standing valve 36. The ball type standing valve 36 comprises a valve cage 62 which is most clearly illustrated in FIGURE 2 of the drawings. The valve cage 62 has an axial bore 64 extending upwardly thereinto from its lower end and is also provided with a second axial bore which extends into the valve cage from the upper end thereof.
At its external peripheral surface, the valve cage 62 is longitudinally grooved with a plurality of circumferentially spaced grooves 65 which extend from the upper end of the cage over a major portion of the longitudinal length thereof. The external periphery of the lower portion of the cage 62 is not, however, grooved and provides a sliding, sealing fit of the valve cage with the internal wall of the working barrel 10.
A suitable annular valve seat 7@ is press fitted or otherwise suitably secured in the axial bore 64 at the lower end of the valve cage 62 and is retained therein by the fitting 60. A spherical valve member 72 is positioned in the bore 64 above the annular valve seat 70 and is dimensioned to permit free floating or reciprocating movement in the axial bore 64 of the valve cage 62 as oil passes through the cage. It will be understood, of course, that on the downstroke of the pump, the column of oil retained above the standing valve 18 in the lower end of the working barrel 1%) will be forced upwardly through the sleeves 38 and 34, and the spherical valve member 72 will be lifted from the seat 70 to permit the oil to pass through the radial aperture 68 into the longtudinal grooves 65 and out into the surrounding working barrel It). On the upstroke of the pump, the column of oil above the ball type standing valve 36 forces the spherical valve member 72 onto the annular seat 70 so that retrograde flow of oil downwardly past the ball type standing valve 36 is precluded.
Operation After the pump has been installed in the lower end of a string of well tubing, and the upper connecting rod 12 has been connected to the usual sucker rod string, the upper sleeve 34 connecting rod 3% and head 28 will be reeiprocated as the sucker rod string is reciprocated. Of course, in the event additional connecting rods 39 and heads 28 are connected in tandem below the single connecting rod 30 and head 28 illustrated in the accompanying drawings, all of the interconnected heads and rods will also be reciprocated. Upon upward reciprocation of the pump, the sleeve 38 slidably mounted in the working barrel will be seated upon the seating surface 46 at the upper end of the head 28. The column of Oil standing m me working barrel 10 above the head 28 will thus be prevented from bypassing the head 28 and will be lifted upwardly as the upward reciprocation of the pump continues. Upward reciprocation of the pump also has the effect of seating the spherical valve member 72 upon the annular seat 70 so that passage of oil through the valve cage 62 and into the axial bore of the sleeve 34 is prevented. The weight of the column of oil standing in the working barrel above the ball type standing valve 36 will be carried by the closure of this valve and only the weight of the column of fluid contained in the lower sleeve 38, upper sleeve 34 and working barrel 10 between the head 28 and the upper standing valve 36 will be imposed upon the seal formed between the head 28 and the lower end 48 of the lower sleeve 38. It will be apparent that, as the upstroke of the pump continues, closure of the ball type standing valve 36 and the valve formed by the sleeve 38 and the head 28 will produce a suction in the lower end of the working barrel 10 to cause oil to flow upwardly through the standing valve in the lower end of the working barrel.
When the stroke of the pump is reversed and downward movement of the plunger and standing valve assembly is commenced the lower sleeve 38 will tend to remain stationary in the working barrel 10 due to the friction fit of the sleeve in the working barrel. At stroke turnaround, the ball type standing valve 36 is opened by movement of the spherical valve member 72 ofl the annular seat 70 and the sleeve 34 and valve cage 62 commence to move downwardly through the column of oil standing above the standing valve 18 in the lower end of the working barrel 10. During the initial portion of the downward stroke, the head 28, connecting rod 30 and upper sleeve 34 will move downward relative to the lower sleeve 38 to unseat the head 28 from the tapered lower end portion 48 of the lower sleeve. The downward movement of the upper sleeve 34 relative to the lower sleeve 38 continues until the connecting member 32 rests upon the upper end 53 of the lower sleeve. At this time, fluid flows upwardly through the connecting member 32 and upper sleeve 34 by virtue of the greater depth of the grooves 52 in the connecting member than the thickness of the wall of the lower sleeve 38.
It will be understood that the standing valve 18 will seat upon the seat 24 when the downstroke of the pump is begun due to the increased pressure in the lower end portion of the working barrel 10 relative to the pressure of the fluid standing in the well and in the anchor 22. The downward stroke of the pump provides, in effect, a displacement of oil from the lower portion to the upper portion of the working barrel it above the piston and traveling valve assembly. At the completion of the downstroke, the direction of movement of the head 24, connecting rod 30 and sleeve 34 is reversed. The floating lower sleeve 38 will, however, tend to remain stationary in the working barrel 1%.
During the irr'tial portion of the upstroke, the spherical valve member 72 of the ball type standing valve 35 will immediately seat upon its annular seat 70 and prevent oil from flowing downwardly through the upper sleeve 34 and connecting member 32 into the floating lower sleeve 38. The oil which is contained in the sleeves 34 and 38 below the ball type standing valve 36 will, however, flow downwardly past the head 28 and no pumping action will take place. However, after the head 28 has been moved upwardly a relatively short distance, the head will contact the lower end 48 of the lower sleeve 38 and the lower sleeve will be seated upon the seat 46 of the head to again provide a pumping action in the manner previously described. The seal which is established between the seating surface 46 on the head 28 and the lower end 48 of the floating sleeve 38 will be subjected to less hydrostatic head than it has previously supported as a result of the preliminary closing of the standing valve 36 to isolate'the floating sleeve 38 and head 28 from the column of oil above the upper standing valve.
When it is desired to lift a longer and heavier column of fluid with the pump of the invention, the plunger and traveling valve assembly illustrated in FIGURES l and 1A of the drawings may be duplicated by the connection of additional connecting rods 30 and heads 28 in series or tandem to the connecting rod and had shown in the drawings. It is also within the scope of the invention to include additional connecting rods, floating sleeves, heads and ball type standing valve assemblies which are connected above the upper standing valve 36 shown in the drawings. In other words, the arrangement illustrated in the drawings of the present application may be substantially duplicated by the addition of one or more of each of the elements there shown or, under some circumstances, it may be desirable merely to incorporate in the assembly additional connecting rods 39 and heads 28 which are connected below the single connecting rod and head shown in the drawings of this application and which function to extend the operating depth of the pump over that which is obtainable with the arrangement illustrated.
From the foregoing description of the invention, it will be apparent that the present invention is a useful improvement over head and connecting rod type sucker rod pumps such as those illustrated and described in the Crowl et al. patent to which reference has hereinbefore been made. Versatility of the pump i not decreased by the alterations in the structure herein proposed, but the effective service life of the pump is extended by virtue of the relief of the standing valve formed bet-ween the head and the floating sleeve with which it cooperates from a substantial portion of the hydrostatic load to which it is otherwise subjected. The desirable washing action which is characteristic of the heads 23 by virtue of their grooved outer peripheral surfaces is retained and, in iiact, is enhanced by the use of a connecting member of similar construction for connecting the head to the upper sleeve which carries the ball type standing valve. The use of the elongated upper sleeve for supporting the cage which houses the ball type standing valve and for connecting the ball .type standing valve assembly through the connecting member to the connecting rod which is secured to the upper end of the head provides a substantial increase in the integrity of the seal which is afforded between the standing valve members and the internal wall of the working barrel. In other words, the sliding fit of the elongated upper sleeve which carries the ball type standing valve cage assures that there can be little or no leakage around the plunger and traveling valve assembly during the upstroke of the pump. This sleeve thus functions to complement the sealing action afiiorded .by the lower floating sleeve provided in the Crowl pump, and further improves the chiciency of the Crowl pump and its eflective service life.
Although a number of modifications and innovations in the described structure and arrangement of parts of the present invention will occur to those skilled in the art, it is intended that insofar as such changes and alterations do not depart from reliance upon the basic concept of the present invention, these changes shall be encompassed within the spirit and scope of the present invention except as the same is necessarily limited by the appended claims or reasonable equivalents thereof.
I claim:
1. An oil well pump comprising:
(a) a tubular barrel;
(b) a standing valve in the lower end of the barrel to prevent downward flow of oil from the barrel;
(c) at least one tubular sleeve slidingly mounted in said tubular barrel and sealingly engaging at its outer periphery-the internal wall of said barrel;
(d) a head positioned in said barrel below said tubular sleeve and adapted to seal the lower end of said tubular sleeve, said head having fluid deflecting grooves therein dimensioned and configured to deflect oil moving upwardly past said head radially outwardly against said barrel;
(e) a valve cage slidingly positioned in said barrel above said tubular sleeve and sealingly engaging at its outer periphery the internal walls of said barrel;
(i) a valve seat in said valve cage;
(g) a valve member above said valve seat in said valve cage and movable in said cage into and out of seating engagement with said valve seat;
(h) a rod of longer axial length than said sleeve interconnecting said valve cage and said head for unitary reciprocating movement in said barrel; and
(i) means connected to said valve cage and cooperating with said head to reciprocate said sleeve in said barrel in a shorter reciprocating stroke than the reciprocating stroke of said valve cage and head during operation of the pump, said means connected to said valve cage including fluid passageway means for permitting fluid flowing upwardly from said tubular sleeve to pass through said valve seat during the upward movement of said rod, valve cage and head.
2. An oil well pump comprising:
(a) -a tubular barrel;
(b) a standing valve in the lower end of the barrel to prevent downward flow of oil from the barrel;
(c) a first tubular sleeve slidingly mounted in said tubular barrel and sealingly engaging at its outer periphery .the internal wall of said barrel;
((1) a valve cage secured to the upper end of said first tubular sleeve and having apertures therethrough to place the bore of said first tubular sleeve in communication with the bore of said tubular barrel;
(e) a valve seat in said valve cage below said apertures;
(f) a valve member above said valve seat in said valve cage and movable in said cage into and out of seating engagement with said valve seat;
(5;) a string of sucker rods in said tubular barrel above said valve cage and connected to said valve cage; (h) a second tubular sleeve having an outer diameter dimensioned to provide a sliding fit in the bore of said tubular barrel and positioned below, and spaced from, said first tubular sleeve;
(i) a generally cylindrically shaped head below aid second sleeve in said barrel and dimensioned to slidingly fit in said barrel, said head having at least one longitudinal groove in the outer periphery extending from end to end thereof, with the depth of said groove being less at the upper end of the head than at the lower end of the head; and
(j) a rod of longer axial length than said second tubular sleeve extending through said second tubular ileege and connected to said cylindrically shaped (k) means connecting said rod to said first tubular sleeve and having a fluid passageway therethrough communicating with the interior of said first tubular sleeve whereby fluid can flow from said second tubular sleeve upwardly in said barrel and into said first tubular sleeve.
3. In a reciprocating oil well sucker rod pump having a standing valve in the lower end of a working barrel, the
improvement which comprises:
(a) a cylindrically shaped head slidingly positioned in. said barrel and having at least one longitudinal groove in the outer periphery thereof extending from end to end thereof, with the depth of the groove being less at the upper end of the head than at the lower end of the head;
(b) a first tubular sleeve slidingly fitted in said barrel above the cylindrically shaped head and having a wall thickness greater than the depth of said groove at the upper end of said head, the adjacent ends of said head and first sleeve being complementary in shape to form a seal when said head and sleeve contact each other at their adjacent ends;
(c) a second tubular sleeve slidingly fitted in said barrel above said first tubular sleeve and sealingly engaging at its outer periphery the internal Walls of said barrel;
((1) a valve cage secured to the upper end of said second tubular sleeve and having apertures therethrough to place the bore of said second tubular sleeve in communication with the bore of said working barrel above said second tubular sleeve, said valve cage being adapted for connection to the lower end of the sucker rod string of the pump;
(e) a valve seat in said valve cage below said apertures;
(f) a valve member above said valve seat in said valve cage and movable in said cage into and out of seating engagement with said valve seat; and
(g) rod means of longer length than said first sleeve extending through the bore of said first sleeve and interconnecting the cylindrically shaped head and said second sleeve, said rod means having a hollow, radially apertured upper end portion connected to the lower end of said second sleeve for passing fluid from the bore of said second sleeve into the bore of said first sleeve.
4. A pump as claimed in claim 3 and further characterized in that the outer portion of the upper end of said head is tapered downwardly and outwardly and the lower end of said first tubular sleeve is tapered upwardly and inwardly to sealingly mate with the tapered outer portion of the upper end of said head.
5. A pump as claimed in claim 3 wherein said head is provided with an axial bore extending therethrough and threaded at its lower end for connection to a downwardly extending rod.
6. A pump as claimed in claim 3 wherein the hollow, radially apertured upper end portion of said rod means comprises an axially bored, generally cylindrical member connected to said second sleeve with its bore communicating with the bore of said second sleeve and having at least one longitudinal groove in the outer periphery thereof extending from end to end thereof, with the depth of the groove being less adjacent the upper end of the head than at the lower end of the head, and said cylindrical member further having a radial aperture placing the axial bore of said cylindrical member in communication with each longitudinal groove.
References Cited by the Examiner UNITED STATES PATENTS 1,545,722 7/25 Zublin 103-225 1,500,963 8/25 Jackson 103--l79 2,933,050 4/60 Crowl et a1 103179 3,109,384 11/63 Adams 103-179 LAURENCE V. EFNER, Primary Examiner.
WARREN E. COLEMAN, Examiner.

Claims (1)

1. AN OIL WELL PUMP COMPRISING: (A) A TUBULAR BARREL; (B) A STANDING VALVE IN THE LOWER END OF THE BARREL TO PREVENT DOWNWARD FLOW OF OIL FROM THE BARREL; (C) AT LEAST ONE TUBULAR SLEEVE SLIDINGLY MOUNTED IN SAID TUBULAR BARREL AND SEALINGLY ENGAGING AT ITS OUTER PERIPHERY THE INTERNAL WALL OF SAID BARREL; (D) A HEAD POSITIONED IN SAID BARREL BELOW SAID TUBULAR SLEEVE AND ADAPTED TO SEAL THE LOWER END OF SAID TUBULAR SLEEVE, SAID HEAT HAVING FLUID DEFLECTING GROOVES THEREIN DIMENSIONED AND CONFIGURED TO DEFLECT OIL MOVING UPWARDLY PAST SAID HEAD RADIALLY OUTWARDLY AGAINST SAID BARREL; (E) A VALVE CAGE SLIDINGLY POSITIONED IN SAID BARREL ABOVE SAID TUBULAR SLEEVE AND SEALINGLY ENGAGING AT ITS OUTER PERIPHERY THE INTERNAL WALLS OF SAID BARREL; (F) A VALVE SEAT IN SAID VALVE CAGE; (G) A VALVE MEMBER ABOVE SAID VALVE SEAT IN SAID VALVE CAGE AND MOVABLE IN SAID CAGE INTO AND OUT OF SEATING ENGAGEMENT WITH SAID VALVE SEAT; (H) A ROD OF LONGER AXIAL LENGTH THAN SAID SLEEVE INTERCONNECTING SAID VALVE CAGE AND SAID HEAD FOR UNITARY RECIPROCATING MOVEMENT IN SAID BARREL; AND (I) MEANS CONNECTED TO SAID VALVE CAGE AND COOPERATING WITH SAID HEAD TO RECIPROCATE SAID SLEEVE IN SAID BARREL IN A SHORTER RECIPROCATING STROKE THAN THE RECIPROCATING STROKE OF SAID VALVE CAGE AND HEAD DURING OPERATION OF THE PUMP, SAID MEANS CONNECTED TO SAID VALVE CAGE INCLUDING FLUID PASSAGEWAY MEANS FOR PERMITTING FLUID FLOWING UPWARDLY FROM SAID TUBULAR SLEEVE TO PASS THROUGH SAID VALVE SEAT DURING THE UPWARD MOVEMENT OF SAID ROD, VALVE CAGE AND HEAD.
US266634A 1963-03-20 1963-03-20 Oil well pump Expired - Lifetime US3186354A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4332533A (en) * 1979-09-13 1982-06-01 Watson International Resources, Ltd. Fluid pump
EP0129018A2 (en) * 1983-04-21 1984-12-27 Harry L. Spears Fluid pump
US4599054A (en) * 1984-08-23 1986-07-08 Spears Harry L Travelling valve assembly for a fluid pump
US4708597A (en) * 1982-09-29 1987-11-24 Intevep, S.A. Plunger with simple retention valve

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1500963A (en) * 1922-06-06 1924-07-08 Walter E Wilson Combined drill and grinding machine
US1545722A (en) * 1923-12-11 1925-07-14 John A Zublin Pump
US2933050A (en) * 1957-05-23 1960-04-19 Reynolds Oil Well Pumps Inc Oil well pump
US3109384A (en) * 1961-01-13 1963-11-05 Reynolds Oil Well Pumps Inc Fluid pump construction

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1500963A (en) * 1922-06-06 1924-07-08 Walter E Wilson Combined drill and grinding machine
US1545722A (en) * 1923-12-11 1925-07-14 John A Zublin Pump
US2933050A (en) * 1957-05-23 1960-04-19 Reynolds Oil Well Pumps Inc Oil well pump
US3109384A (en) * 1961-01-13 1963-11-05 Reynolds Oil Well Pumps Inc Fluid pump construction

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4332533A (en) * 1979-09-13 1982-06-01 Watson International Resources, Ltd. Fluid pump
US4708597A (en) * 1982-09-29 1987-11-24 Intevep, S.A. Plunger with simple retention valve
EP0129018A2 (en) * 1983-04-21 1984-12-27 Harry L. Spears Fluid pump
EP0129018A3 (en) * 1983-04-21 1985-01-30 Harry L. Spears Fluid pump
US4599054A (en) * 1984-08-23 1986-07-08 Spears Harry L Travelling valve assembly for a fluid pump

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