US2699154A - Oil well pumping apparatus - Google Patents

Description

Jan- 11, 1955 s. v. SMITH OIL WELL PUMPING APPARATUS Filed my 12, 1952 SAMUEL 63M/ TH 1N V EN TOR.

United States Patent O M' OIL WELL PUIVIPING APPARATUS Samuel V. Smith, Long Beach, Calif.

Application July 12, 1952, Serial No. 298,586

Claims. (Cl. 121-164) This invention relates to improved well pump actuating units or jack devices, to be located at the surface of the earth and vertically reciprocate a pump actuating sucker rod, connected to a pump at a location deep within a well.

The pump jack of the present invention is of a type in which forces exerted by two dilferent pressure fluids act against the pump rod, and are so related as to produce a composite actuating force not attainable by a single uid. Specifically, one of the fluids is a compressed gas such as air, which exerts an upward force acting to approximately balance the weight of the pump rods and half the iluid and frictional loads on the jack, while the second fluid, preferably a liquid, exerts a reversing force acting to reciprocate the rod.

A major object of the invention is to provide a jack device of the above character in which the pressure uids are so controlled as to exert a considerably greater actuating force against the sucker rod during the initial stages of its upstroke than during the rest of its upstroke or its downstroke. As will be appreciated, such an increased actuating force is desirable at the beginning of the upstroke in order to rapidly accelerate the rod and pump piston on the pumping stroke, and thus attain an overall pumping cycle of maximum effectiveness.

The desired increase in actuating force as the upstroke begins is attained by providing for an automatic variation in the rod supporting force of the compressed gas. That is, this gas force is varied in accordance with the rod movements, and in a manner such that the upward force exerted by the gas increases at the bottom of the pump and rod stroke.

structurally, the apparatus includes a power piston which is reciprocated within a power Jcylinder by the main actuating huid, and a gas chamber which is received about the power cylinder and is connected to its piston for reciprocation therewith. As the gas chamber moves with the piston, it acts to automatically vary the gas pressure, in a manner producing a progressive increase in rod supporting force as the rod is moved downwardly. More specifically, the chamber movement varies the volume of gas displaced by the main cylinder structure within the gas chamber, to thus effect the desired Variation in gas pressure. Preferably, the gas chamber is guided for its movement by a sliding engagement with the outer surface of the main cylinder structure. Particularly contemplated is an arrangement in which this main cylinder structure includes a tubular sleeve extending about the cylinder proper and spaced from it to form therewith a space through which the power fluid is directed to one end of the cylinder. This outer sleeve may then be the portion of the cylinder structure which is slidably engaged by the gas chamber.

Certain particular features of the invention have to do with the provision of a tubular hood about the cylinder and gas chamber structure, to which may be mounted means for actuating a valve for controlling the de livery of pressure fluid to the power cylinder. These valve actuating means may comprise elements engaged and operated by a cam or other element carried by and movable with the gas chamber.

Preferably, the entire jack unit is so constructed as to be connectable directly to and supported by a conventional well head structure.

The above and other features and objects of the present invention will be better understood from the follow- 2,699,154 Patented Jan. 11, 1955 ing detailed description of the typical embodiments illustrated 1n the accompanying drawing, in which:

Fig. 1 is a vertical section through a well pump jack unit embodying the invention;

Fig. 2 is a horizontal section through the valve actuating mechanism taken on line 2 2 of Fig. l; and

Flg. 3 is a vertical section through the valve actuating mechanism taken on line 3 3 of Fig. l.

Referring first to Fig. l, the illustrated well pump jack unit 10 includes a vertically extending power cylinder structure 11, within which is positioned a vertically reciprocable power piston 12. Cylinder structure 11 projects upwardly into a vertically elongated outer chamber 13, which contains compressed air or other gas, and is connected by rod 14 with power piston 12 for vertical reciprocation therewith. A vertically extending and upwardly opening hood 15 extends about the cylinder structure and air chamber 13, and carries mechanism 16 for actuating the usual pressure fluid controlling pilot and main valves 17 and 18. The cylinder structure 11 and hood 15 are mounted on a base member 19, which is connectable by a bottom four-way tting 20 to a conventional well head structure 21 of an oil well. Fitting 20 is threadedly connectable at its upper and lower ends 22 and 23 to base member 19 and well head structure 21 respectively. At its opposite sides 24 and 25, t ting 20 is threadedly connectable to lines 26 and 27, through which oil is taken from the well during production, or treating uids are injected into the well.

Piston 12 is connected by a rod 28, extending vertically through base member 19 and litting 20, to the usual sucker rod (not shown), which vertically reciprocates a well pump located deep within the well. Packing is provided about rod 28 at 29 and 30 to prevent fluid escape downwardly about rod 28 from cylinder structure 11, or upwardly about the rod from fitting 20. To facilitate the insertion of such packing, base member 19 may contain a transverse opening 31, for receiving the packing and its glands or retaining elements 32 and 33.

The power cylinder structure 11 includes an inner elongated vertically extending open-ended cylinder proper 34, which is threadedly connected at its lower end 35 into base member 19. Piston 12 directly engages and is vertically reciprocable within this cylinder proper 34. The actuating pressure fluid, preferably a liquid such as oil, is alternately admitted to and discharged from the lower end of cylinder 34 through a passage 36 in base 19 leading from a fluid line 37. For similarly introducing iiuid to and discharging it from the upper end of cylinder 34, cylinder structure 11 includes an outer cylindrical vertically extending fiuid supply pipe 38, which is mounted concentric with and radially spaced from cylinder 34, to form between the cylinder and pipe 38 an annular vertically extending uid supply passage 39. Fluid flows into and out of the lower end of this passage through a passage 40 in base member 19, which communicates with a line 41 leading from control valve 18. At its upper end, passage 39 communicates with the open upper end 42 of cylinder 34. The outer fluid supply pipe may be mounted at its lower end in any suitable manner to base 19, as for instance by an annular mounting ring 43, which forms an annular iluid tight seal between the lower end of pipe 38 and the base. At its upper end, outer pipe 38 of the cylinder structure carries an upper head unit 44 through which rod 14 from the piston projects upwardly, and containing packing 45 and 46 acting to prevent fluid leakage in either direction along rod 14.

Air chamber 13 is preferably cylindrical and vertically elongated and mounted concentrically with cylinder 34 and pipe 38. The air chamber is radially spaced from pipe 38 to form about the pipe a space 47 within which the compressed air or other gas is contained. At its upper end, chamber 13 is closed by an upper wall 48, which is centrally attached to rod 14, to interconnect the air chamber and piston 12 for vertical reciprocation and unison. At its upper side, top wall 48 of the air chamber may carry on eye 49 for connecting the chamber and piston to external actuating mechanism when desired.

At its lower end, air chamber 13 carries a transverse annular inwardly projecting bottom wall or ring 5t), which in turn carries a bushing or bearing member 51 acting to slidably engage pipe 38 and guide the air chamber for its vertical reciprocation with the piston. Bushing member 51 may be attached to bottom wall 50 of the air chamber in any suitable manner, as for instance by a number of circularly spaced screws 52. The bushing member is of a configuration to have a pair of vertically spaced upper and lower annular portions 53 and 54 slidably engaging pipe 38, and to form between these portions a recess 55 at which the bushing is spaced from the pipe. A body of oil 56 is contained within the lower portion of the air chamber, and is accessible to recess 55 through openings 57 in the bushing body, to lubricate the engagement between the bushing and pipe 38. The upper pipe engaging portion 53 of the bushing may carry a pair of replaceable or other bushing ends 58, while the lower pipe engaging portion 54 of the bushing may carry a pair of liuid seal rings 59 (typically rubber O-rings). The oil 56 in the bottom of the air chamber. in addition to acting as a lubricant, serves to increase the elfectiveness of the ud seal formed by rings 59, to positively prevent the leakage of any air from the air chamber.

Outer hood may be cylindrical and concentric with cylinder 34, pipe 3S, and air chamber 13, and is rigidly mounted at its lower end 60 to base 19. At one of its sides, hood 15 carries a pair of vertically spaced outwardly projecting housings 61 and 62, which carry the valve actuating mechanism 16. Contained within these housings are a pair of arms 63 and 64, which are mounted for vertical swinging movement and which pivotally carry at their inner ends terminal elements 65 and 66. These terminal elements project into hood 15 through openings 67 in the side thereof, and are engageable and deliectible, upon vertical movement of air chamber 13, by an annular cam element 68 carried at the bottom of the air chamber. As will be understood, the upper arm 63 is deliectible upwardly by cam 68 as the piston and air cylinder approach the upper limit of their travel, while the lower arm 64 is deectible downwardly as the piston and air chamber approach the lower limit of their travel. The terminal elements 65 and 66 carried by arms 63 and 64 are of a conventional construction to each be deflectible relative to the corresponding arm by cam movement in one direction, while cam movement in the reverse direction acts to deflect the terminal element and corresponding arm as a unit, so that arm 63 is deilectible only by upward movement of the cam, while arm 64 is deectible only by downward movement of the cam.

Each of the arms 63 and 64 is carried and mounted for its swinging movement by a shaft 69, which is rotatably journalled within ball bearing 70. Each of the shafts 69 carries a bevel gear 71, which engages and rotatably oscillates in accordance with swinging movement of the arm, a bevel gear 72 contained within a cylindrical housing 73 at the side of one of the housings 61 or 62. The two bevel gears 72 associated with the two swinging arms 63 and 64 are connected to and actuate a common vertically extending shaft 74. As will be understood, arms 63 and 64 through their gear drives 71, 72 act to rotatably oscillate shaft 74 in accordance with vertical reciprocation of piston 12 and air cylinder 13. This rotary oscillation of shaft 74 is translated into axial reciprocation of valve element 174 of pilot valve 17, to control the delivery of pressure lluid to power cylinder 34. For effecting this translation of energy, rod 74 carries at its lower end a laterally projecting arm 75, which swings in accordance with rotary movement of rod 74, and is pivotally connected to pilot valve element 174.

Oil or other actuating fluid under pressure is supplied to pilot valve 17 and main valve 18 through central supply lines 76 and 77 respectively. The actuating uid is returned from the two valves to the usual accumulator tank through lines 78, 79, 80 and 81 near the opposite ends of the valves. Actuating fluid is delivered between the pilot valve and the opposite ends of main valve 18 through lines 82 and 83.

Valve element 174 of pilot valve 17 is of conventional construction to alternately admit actuating fluid from line 76 to the opposite end of main valve 18 through the lines S2 and 83 respectively. When the Huid is being passed by pilot valve 17 to one end of the main valve, the opposite end of the main valve is placed in communication with one of the fluid discharge lines 78 and 79, so that inner element 84 of the main valve is caused t0 reciprocate between its illustrated full-line and brokenline positions in accordance with reciprocation of the pilot valve. In the full-line position of the main valve element, pressure liuid is supplied to the lower end of cylinder 34 through line 37, and is discharged from its upper end through lines 41 and St). The piston is thus actuated upwardly, until cam 68 actuates arm 63 upwardly, to move pilot valve element 174 to the left, effecting corresponding leftward movement of main valve element 84, so that pressure tluid is admitted to the upper end of cylinder 34 and discharged from its lower end to actuate the piston downwardly.

The air or other gas within chamber 13 is maintained at such a pressure as to continuously exert a substantial upward force against the air chamber and the connected piston 12 and well pump. This air pressure preferably is suicient to approximately balance the weight of the well pump piston, sucker rods, half the uid load in the piston, and half the frictional loads on the piston and rods. As the piston and air chamber 13 move downwardly together, the pressure within chamber 13 progressively increases, since cylinder structure 11 occupies an increasing volume within the air chamber. This increased air pressure causes a maximum upward force to be exerted against the air chamber and piston at the beginning of their upward stroke, to rapidly accelerate them and increase the overall effectiveness of the pumping section.

I claim:

l. A well pump jack comprising a power cylinder, a fluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder and reciprocable relative thereto with the piston, and a connection interconnecting said piston and chamber for said reciprocation together.

2. A well pump jack comprising a power cylinder, a uid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, means for introducing pressure luid to a first end of said cylinder, a tubular member extending about said power cylinder in spaced relation thereto and forming therewith a passage through which pressure fluid is delivered to a second end of the cylinder, a compressed gas containing pressure tight chamber extending about said cylinder and said tubular member and reciprocable relative thereto with the piston, and a connection interconnecting said piston and chamber for said reciprocation together.

3. A well pump jack comprising a power cylinder structure, a lluid pressure actuated piston reciprocable in said cylinder structure and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder structure and reciprocable relative thereto with the piston, a connection interconnecting said piston and chamber for said reciprocation together, and interengaging bearing means on said charnber and said cylinder structure guiding the chamber for said relative reciprocation.

4. A well pump jack comprising a generally vertically positioned power cylinder, a lluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, a compressed gas containing pressure tight charnber extending about said cylinder and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, and a connection interconnecting said piston and chamber for said reciprocation together.

5. A well pump jack comprising a generally vertically positioned power cylinder structure, a fluid pressure actuated piston reciprocable in said cylinder structure and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder structure and reciprocable generally vertically relative thereto with the piston, said cylinder structure projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, and bearing means carried by said chamber slidably engaging said cylinder structure and guiding the chamber for'said relative reciprocation.

6. A well pump jack comprising a generally vertically positioned power cylinder, a fluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, and a tubular vertically extending hood disposed about said chamber and into and out of which a portion of said chamber is movable upon said reciprocation.

7. A well pump jack comprising a generally vertically positioned power cylinder, a fluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, a tubular vertically extending hood disposed about said chamber and into and out of which a portion of said chamber is movable upon said reciprocation, valve means for alternately admitting pressure iiuid to opposite sides of said piston, movable means mounted on said hood for actuating said valve means, and means movable with said piston and chamber positioned to engage and operate said valve actuating means.

8. A well pump jack comprising a generally vertically positioned power cylinder structure, a fluid pressure actuated piston reciprocable in said cylinder structure and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder structure and reciprocable generally vertically relative thereto with the piston, said cylinder structure projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, bearing means carried by said chamber slidably engaging said cylinder structure and guiding the chamber for said relative reciprocation, valve means for alternately admitting pressure fluid to opposite sides of said piston, means mounted alongside said chamber for actuating said valve means, and means carried by said chamber operable to engage and operate said last mentioned means in accordance with the chamber movements.

9. A well pump jack comprising a generally vertically positioned power cylinder structure, a fluid pressure actuated piston reciprocable in said cylinder structure and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder structure and reciprocable generally vertically relative thereto with the piston, said cylinder structure projecting upwardly into said chamber through a bottom opening therein and terminating in the chamber so that the cylinder structure acts upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, means forming an annular Huid tight seal between said chamber and cylinder structure at said bottom opening in the chamber, and a connection interconnecting said piston and chamber for said reciprocation together.

10. A well pump jack comprising a generally vertically positioned power cylinder, a iluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, and a rod projecting upwardly from said piston through an upper end of said cylinder and connecting with an upper portion of said chamber to interconnect the piston and chamber for said reciprocation together.

ll. A Well pump jack comprising a generally vertically positioned power cylinder, a fluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, a compressed gas containing pressure tight chamber extending about said cylinder and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and charnber for said reciprocation together, and a threaded mounting fitting carried by and beneath said cylinder structure and threadedly connectable to a well head structure.

12. A well pump jack comprising a generally vertically positioned power cylinder, a fluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, means forming a irst passage for introducing pressure fluid to a lower portion of said cylinder, a tubular member extending vertically about and in spaced relation to said cylinder and forming therewith a second passage through which iluid is delivered upwardly to an upper portion of the cylinder, a compressed gas containing pressure tight chamber extending about said cylinder and said tubular member and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, and a connection interconnecting said piston and chamber for said reciprocation together.

13. A well pump jack comprising a generally vertically positioned power cylinder, a uid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, means forming a first passage for introducing pressure fluid to a lower portion of said cylinder, a tubular member extending vertically about and in spaced relation to said cylinder and forming therewith a second passage through which fluid is delivered upwardly to an upper portion of the cylinder, a compressed gas containing pressure tight chamber extending about said cylinder and said tubular member and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, and a bushing carried by a lower portion of said chamber slidably engaging said tubular member and guiding the chamber for said relative reciprocation.

14. A well pump jack comprising a generally vertically positioned power cylinder, a fluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, means forming a rst passage for introducing pressure fluid to a lower portion of said cylinder, a tubular member extending vertically about and in spaced relation to said cylinder and forming therewith a second passage through which iluid is delivered upwardly to an upper portion of the cylinder, a compressed gas containing pressure tight chamber extending about said cylinder and said tubular member and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, a bushing carried by a lower portion of said chamber slidably engaging said tubular member and guiding the chamber for said relative reciprocation, and annular seal means carried by said chamber about said bottom opening and slidably engaging said tubular member.

l5. A well pump jack comprising a generally vertically positioned power cylinder, a iluid pressure actuated piston reciprocable in said cylinder and connectable to a pump rod, means forming a first passage for introducing pressure Huid to a lower portion of said cylinder, a tubular member extending vertically about and in spaced relation to said cylinder and forming therewith a second passage through which fluid is delivered upwardly to an upper portion of the cylinder, a compressed gas containing pressure tight chamber extending about said cylinder and said tubular member and reciprocable generally vertically relative thereto with the piston, said cylinder projecting upwardly into said chamber through a bottom opening therein and acting upon downward chamber movement to occupy an increasing volume in the chamber and thereby progressively increase the chamber gas pressure, a connection interconnecting said piston and chamber for said reciprocation together, a bushing carried by a lower portion of said chamber slidably engaging said tubular member and guiding the chamber for said relative reciprocation, and annular seal means carried by said chamber about said bottom opening and slidably engaging said tubular member.

References Cited in the le of this patent UNITED STATES PATENTS 2,313,404 Vickers Mar. 9, 1943 2,347,301 Twyman et al Apr. 25, 1944 2,347,302 Twyman et al Apr. 25, 1944 2,363,142 Reed 2,366,777 Farley et al. 2,504,218 Noll et al. Apr. 18, 2,612,142 Smith Sept. 30, 1952

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