CN216241220U

CN216241220U - Short plunger oil-well pump

Info

Publication number: CN216241220U
Application number: CN202122790191.4U
Authority: CN
Inventors: 宋志亮; 王安亚; 万文金
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-11-15
Filing date: 2021-11-15
Publication date: 2022-04-08
Anticipated expiration: 2031-11-15

Abstract

The utility model discloses a short plunger oil pump, wherein an oil pipe is in threaded connection with a pump barrel through an oil pipe coupling and a transition connecting sleeve, the lower end of the pump barrel is connected with a suction inlet pump sleeve, a sucker rod in the pump barrel is connected with a plunger assembly through a sucker rod coupling and a connecting mechanism, an oil drainage hole is arranged on the transition connecting sleeve, a sliding sleeve matched with the oil drainage hole is arranged in the transition connecting sleeve, the sliding sleeve is positioned through a steel ball positioning device, the connecting mechanism consists of a grabbing spring, a guide rod and a reducing connecting pipe which are mutually matched and connected, a shifting sleeve arranged on a grabbing spring connecting rod is matched with the sliding sleeve, a locking spring and a locking nut are arranged on the guide rod with a guide connector at the upper end, and a grabbing claw of the grabbing spring is matched with the guide connector of the guide rod. The utility model has reasonable structure, safe and reliable performance, short length of the plunger of the oil well pump, good energy-saving effect, good sealing performance of the oil well pump and improved pump efficiency, and greatly reduces the friction resistance between the plunger and the inner wall of the pump barrel, eliminates the defect of pump clamping.

Description

Short plunger oil-well pump

Technical Field

The utility model relates to the field of oil exploitation equipment, belongs to the improvement of an oil well pump structure for pumping an underground oil reservoir, and particularly relates to a short-plug oil well pump.

Background

At present, the oil extraction process generally adopts the traditional long plunger tube type or rod type oil well pump, and the traditional oil well pump has a plurality of problems in structural design and processing and manufacturing. The long plunger tube type or rod type oil well pump of the prior art adopts the long plunger design to reduce leakage in the process of rapid movement in order to prolong the service life of the oil well pump, and brings many faults to equipment due to the heterogeneity of oil deposit and the problems of structural design and processing and manufacturing in the operation process of the oil well pump, thus causing the working efficiency of the oil well pump to be very low.

For the convenience of observation and analysis, taking a phi 57 tubular pump as an example, in the machining process of the inner diameter of a pump cylinder, many machining and production enterprises are caused to clamp the pump of a long plunger in the movement process due to the fact that machining precision of machining equipment is not high, the straight line and the concentricity of the inner diameter of the machining pump cylinder are difficult to guarantee, particularly in thick oil production, the pump clamping phenomenon of fine sand is more serious and almost accounts for 50-60% of the workload of pump detection, and wax clamps are mainly shown in thin oil production. The long plunger is convenient to install in the design structure, the upper end and the lower end of the long plunger are provided with the guide tips, the fluid is non-homogeneous, fine sand and paraffin cannot be avoided in the fluid, and the fine sand and the paraffin are accumulated and deposited between the guide tips and the inner diameter of the oil pumping cylinder for a long time, so that the pump blockage is easily caused. The longer the plunger, the greater the frictional resistance generated, and the greater the power loss. If the viscosity of crude oil changes, the mechanical transmission oil pumping unit can be generated, the descending speed of the plunger cannot be synchronous with the mechanical speed, stroke loss can be caused, the sucker rod deforms in an oil pipe, and the phenomenon that the sucker rod is broken or the oil pipe is worn through for a long time can be caused.

In addition, the pumping efficiency of the oil well pump is different, gas and water are accompanied in the oil reservoir, and the viscosity of crude oil changes along with the change of temperature, so that the fluid of the oil reservoir has great heterogeneity. Under the same condition, the leakage amount of several fluids with different viscosities is greatly different through the gap between the inner diameter of the oil well pump and the plunger, the smaller the viscosity is, the larger the leakage amount is, the larger the negative pressure loss of the suction inlet of the oil well pump is, the lower the pump efficiency is, and the pump efficiency of the underground oil well pump is only 20% -30%, which is the current situation of the current oil extraction production.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a short-plunger oil well pump which is reasonable in structure, safe and reliable in performance, short in plunger length, good in energy-saving effect, capable of greatly reducing the friction resistance between the plunger and the inner wall of a pump cylinder, capable of eliminating the defect of pump clamping, good in sealing performance, capable of improving the pump efficiency and capable of meeting the exploitation operation of oil plants with various properties.

The purpose of the utility model is realized as follows: a short plug oil pump, the oil pipe is connected with the pump barrel through the oil pipe coupling and the transition connecting sleeve thread, the lower end of the pump barrel is connected with the suction inlet pump sleeve, the oil pumping rod in the pump barrel is connected with the plunger assembly through the oil pumping rod coupling and the connecting mechanism, the transition connecting sleeve is provided with the oil drainage hole, the transition connecting sleeve is provided with the sliding sleeve matched with the oil drainage hole, the sliding sleeve is positioned through the steel ball positioning device, the connecting mechanism is composed of a grab spring, a guide rod and a reducing connecting pipe which are mutually matched and connected, wherein a shifting sleeve arranged on the grab spring connecting rod is matched with the sliding sleeve, a locking spring and a locking nut are arranged on the guide rod with a guide connecting head at the upper end, a grab claw of the grab spring is matched with the guide connecting head of the guide rod and locks the guide rod through the locking sleeve, the lower end of the guide rod is connected with the reducing connecting pipe with the oil outlet through the thread, and a thread pipe at the lower end is connected with the plunger assembly through the thread, the plunger assembly has piston ring and sealing ring installed outside the plunger, plunger check valve unit installed on the fluid passage inside the plunger, steel ball check valve unit installed in the lower port of the fluid passage, and sucking port check valve unit installed inside the sucking port pump sleeve.

The external part of the utility model is composed of an oil pipe, an oil pipe coupling, a transition connecting sleeve, a pump cylinder and a suction inlet pump sleeve which are connected by screw threads. The oil pumping rod, the oil pumping rod coupling and the grabbing spring are connected in a threaded manner, the grabbing spring connecting rod is connected in series with the poking sleeve, the poking sleeve is made of soft wear-resistant and high-temperature-resistant materials, the poking sleeve and the locking nut are tightly matched for preventing the oil pumping rod coupling and the grabbing spring from loosening and falling off, the sliding sleeve of the poking sleeve which is connected in series on the grabbing spring is poked downwards to seal an oil drainage hole in the transitional connecting sleeve, and for preventing the sliding sleeve from moving up and down in working, the transitional connecting sleeve is provided with the positioning steel ball, the positioning steel ball spring and the screw plug for positioning the sliding sleeve up and down. The grabbing spring is butted with the guide rod, the plunger assembly is pushed into a flow guide disc of a suction inlet at the bottom of the oil well pump, the locking sleeve is compressed by the grabbing spring under the action of gravity, when the guide rod enters the grabbing spring, the grabbing spring is quickly contracted by elasticity, and the grabbing spring and the guide rod are locked by pushing the locking sleeve by the locking spring. The guide rod is connected with the reducing connecting pipe through threads, and in order to prevent the guide rod from loosening and falling off from the reducing connecting pipe, a locking nut is installed on the guide rod and is tightly connected with the reducing connecting pipe. The reducing connecting pipe is in threaded connection with the plunger, the piston ring is installed to the plunger external diameter, and in order to improve piston ring life, wear-resistant material U type sealing ring is installed back to back in the upper and lower end of plunger, prevents oil sand or other foreign matters entering when the plunger moves from top to bottom, protection piston ring. The plunger check valve is installed on the plunger fluid channel and is designed in a conical mode, a check spring is installed on a guide rod on the plunger check valve, the guide rod of the plunger check valve is guided and positioned through a guide disc, and the plunger check valve and a plunger check valve seat are designed to be sealed in a linear mode. The plunger check steel ball is installed on the lower portion of the plunger, when the plunger assembly moves upwards, the S surface of the plunger check valve is closed rapidly under the gravity of fluid in the oil pipe, the plunger check steel ball is installed on the plunger check valve, the pumping efficiency of the oil well pump is guaranteed, and the plunger check steel ball and the plunger steel column check valve seat are in line sealing. The locking sleeve is connected with the plunger through threads, and the inner snap spring clamps the plunger steel column check valve seat. The suction inlet of the oil well pump is designed by adopting a suction inlet check valve seat, the structure principle is the same as that of a plunger check valve, only the overflow area of the suction inlet is larger than that of the plunger check valve, when the plunger assembly descends, fluid sucked into a pump barrel instantly overcomes the gravity of a plunger check steel ball and the plunger check valve, the fluid generates internal pressure, the internal pressure exerts pressure on the S surface of the suction inlet check valve and forms resultant force with a check spring at the same time, so that the suction inlet check valve seat is closed rapidly, and the suction inlet check valve seat are designed to be in line sealing. During well repair, the sucker rod is lifted, the sliding sleeve is lifted to the upper limit by the shifting sleeve and the locking sleeve on the plunger assembly, the locking sleeve is limited by the sliding sleeve, the locking spring is compressed, the grabbing spring is separated from the guide rod, the plunger assembly is left in the pump barrel, the oil drainage port is opened on the sliding sleeve, and fluid in the oil pipe can be left in the shaft through the oil drainage port. According to the working condition, if the heavy oil production huff and puff well, the short-plug oil pump can perform steam injection operation. The oil pipe, the oil pipe coupling transition connecting sleeve, the pump barrel and the suction inlet pump sleeve are connected through threads. The sucker rod, the sucker rod coupling and the grabbing spring are connected through threads, the grabbing spring connecting rod is connected with the poking sleeve in series, and the poking sleeve is made of soft wear-resistant and high-temperature-resistant materials and is poked with the locking nut. The shifting sleeve sliding sleeve connected in series with the grab spring moves downwards to seal an oil drainage hole in the transition connecting sleeve, and a positioning steel ball, a positioning steel ball spring and a screwed plug are assembled on the transition connecting sleeve to position the sliding sleeve up and down in order to prevent the sliding sleeve from moving up and down during working. The grabbing spring is in butt joint with the plunger guide rod, the grabbing spring enables the locking spring to be compressed under the action of gravity of the lock sleeve, when the guide rod enters the grabbing spring, the grabbing spring contracts rapidly by elasticity, and the locking spring pushes the lock sleeve to lock the grabbing spring and the guide rod. The guide rod is connected with the reducing connecting pipe through threads, and in order to prevent the guide rod from loosening and falling off from the reducing connecting pipe, a locking nut is installed on the guide rod and is tightly connected with the reducing connecting pipe. The reducing connecting pipe is in threaded connection with the plunger, the piston ring is installed to the plunger external diameter, and in order to improve piston ring life, wear-resistant material U type sealing ring is installed back to back in the upper and lower end of plunger. Install the plunger check valve in the plunger, the plunger check valve adopts the design of tapered type, installs the non return spring on the plunger check valve guide bar, and plunger check valve guide bar passes through guiding disc guiding orientation, and plunger check valve and plunger non return disk seat design are sealed for the line. The lower part of the plunger is provided with a plunger non-return steel ball, the locking sleeve is in threaded connection with the plunger, and the inner snap spring clamps the plunger steel column non-return valve seat. The suction inlet consists of a suction inlet check valve seat, a flow guide disc, a check spring and a suction inlet check valve seat, the guide rod of the suction inlet check valve seat is guided and positioned by the flow guide disc, and the suction inlet check valve seat are designed to be in line sealing.

The short plunger oil pump is composed of tubing coupling, transition connecting sleeve, pump barrel and suction inlet pump sleeve. The pump barrel is internally connected with a guide rod through a sucker rod coupling and a disconnecting device claw spring, the claw spring is connected with the guide rod and then locked by a lock sleeve under the action of a locking spring, the guide rod is in threaded connection with a plunger connecting piece, the plunger connecting piece is in threaded connection with a plunger, a piston ring is arranged outside the plunger, in order to prolong the service life of a piston, wear-resistant material U-shaped rings are arranged back to back at the upper end and the lower end of the plunger, when the plunger moves up and down, the U-shaped rings can push away oil sand or other foreign matters, so that the oil sand or other foreign matters are prevented from entering a gap between the plunger and the pump barrel, the pump and the plunger are prevented from being damaged, and the piston ring is protected. Install the plunger check valve in the plunger, the plunger check valve adopts the design of tapered type, installs the non return spring on the guide bar on the plunger check valve, and guide bar on the plunger check valve passes through guiding disc guiding orientation, and the plunger check valve is sealed for the line with plunger non return disk seat design. The plunger non-return steel ball is arranged at the lower part of the plunger, so that the non-return valve and the plunger non-return steel ball are ensured to be closed in time when the plunger moves upwards, the leakage is reduced, the pumping efficiency of the oil well pump is ensured, and the plunger non-return steel ball seat are designed to be in line sealing. The suction inlet of the oil well pump also adopts a suction inlet check valve, the structure principle is the same as that of a plunger check valve, only the overflow area of the suction inlet is larger than that of the plunger check valve, when the plunger descends, fluid sucked into a pump barrel instantly overcomes the gravity of a plunger check steel ball and the plunger check valve, the fluid generates internal pressure, the internal pressure exerts pressure on the S surface of the suction inlet check valve and forms resultant force with a check spring to rapidly close the suction inlet check valve, and the suction inlet check valve and a suction inlet check valve seat are designed to be in line sealing.

The short plunger piston oil well pump is characterized in that the short plunger piston is arranged in a pump cylinder by a professional tool in a factory, when the short plunger piston is in a site, the short plunger piston, the pump cylinder and an oil pipe are arranged in a preset position of an oil well, a claw spring is connected with a sucker rod through a sucker rod coupling and arranged in the oil well, a shifting sleeve is arranged on the claw spring and is made of soft wear-resistant high-temperature-resistant materials, the shifting sleeve has the function of shifting a sliding sleeve to move up and down, when the claw spring is arranged in the pump cylinder, the shifting sleeve firstly moves down to ensure that an oil drainage port is closed, when the claw spring meets a guide rod on the short plunger piston, the claw spring presses down a lock sleeve and a locking spring by using the weight of the sucker rod until the claw spring is matched with the guide rod, the locking spring locks the lock sleeve and the claw spring, the pump plunger piston works in a normal limit position, and the claw spring cannot fall off the guide rod. If need workover, lift the sucker rod, the lock sleeve on the plunger is lifted the sliding sleeve to the upper limit, and the sliding sleeve restriction lock sleeve, locking spring compression, claw spring and guide bar separation, short column stopper have been stayed in the pump barrel, and the sliding sleeve shifts up the draining opening and opens this moment, and fluid in the oil pipe can stay in the pit shaft through the draining opening. According to the working condition, if the heavy oil production well is stimulated, the short-plug oil well pump can perform steam injection operation.

The utility model has reliable performance and convenient operation, can meet the exploitation operation of oil reservoirs with various properties, has good energy-saving effect and reduces the indirect cost of well repair. In view of the current situation of oil well pump cylinder production, the short-plunger oil well pump plunger sealing length is shortened by 6 times compared with the traditional oil well pump plunger length, the friction resistance between the plunger and the inner diameter of the pump cylinder is greatly reduced, under the same condition, the energy-saving effect of saving electricity by 2-3 kw.h every day is good, and the probability of pump blockage is very little. In order to control the leakage between the plunger and the inner diameter of the pump barrel, the plunger between the plunger and the inner diameter of the pump barrel is made of wear-resistant elastic materials and piston rings, and the gap between the plunger and the inner diameter of the pump barrel is eliminated. The experimental operation on the production site proves that the pump efficiency is over 85 percent, and the performance is safe and reliable.

The oil well pump has the advantages of reasonable structure, safe and reliable performance, short length of the plunger of the oil well pump, great reduction of the friction resistance between the plunger and the inner wall of the pump cylinder, good energy-saving effect, elimination of the defect of pump clamping, good sealing performance of the oil well pump, improvement of the pump efficiency and capability of meeting the exploitation operation of oil plants with various properties.

Drawings

The present invention will be further described with reference to the accompanying drawings, wherein fig. 1 is a front view schematically illustrating a downhole installation of the present invention, fig. 2 is an enlarged upper view schematically illustrating fig. 1, fig. 3 is an enlarged middle view schematically illustrating fig. 1, and fig. 4 is an enlarged lower view schematically illustrating fig. 1.

Detailed Description

A short plug oil pump, as shown in figure 1, the oil pipe 1 is connected with the pump barrel 16 through the oil pipe coupling 3 and the transition connecting sleeve 5, the lower end of the pump barrel 16 is connected with the suction inlet pump sleeve 29, the oil pumping rod 2 in the pump barrel 16 is connected with the plunger assembly through the oil pumping rod coupling 4 and the connecting mechanism, the transition connecting sleeve 5 is provided with the oil drainage hole 8, the transition connecting sleeve 5 is provided with the sliding sleeve 9 matched with the oil drainage hole 8, the sliding sleeve 9 is positioned through the steel ball positioning device, the connecting mechanism is composed of the grabbing spring 12, the guide rod 13 and the reducing connecting pipe 17 which are mutually matched and connected, wherein the poking sleeve 11 arranged on the grabbing spring connecting rod is matched with the sliding sleeve 9, the guide rod 13 with the guide connector at the upper end provided with the guide connector is provided with the lock sleeve 14, the lock spring 15 and the lock nut 10, the grabbing claw of the grabbing spring 12 is matched with the guide connector of the guide rod 13, and the guide rod 13 is locked through the lock sleeve 14, the lower end of the guide rod 13 is screwed to a variable diameter joint pipe 17 having an oil outlet 32, the lower end of the threaded pipe is screwed to a plunger assembly, a piston ring 20 and a seal ring 18 are mounted on the outside of a plunger 19 of the plunger assembly, a plunger check valve device is fittingly mounted to a fluid passage in the plunger 19, a steel ball check valve device is fitted to a lower port of the fluid passage, and a suction check valve device is fittingly mounted to a suction pump casing 29. The structure of the grab spring 12 is that the lower end of the connecting rod is provided with evenly distributed grabs, the lower end of the grabs is provided with a clamping platform matched with a frustum at the rear end of a guide rod guide connector, the connecting rod is provided with a locking nut 10 and a shifting sleeve 11 in a matching way, the locking nut 10 compresses a sucker rod coupling 4, the transition connecting sleeve 5 is provided with a steel ball positioning device, a steel ball 6 controlled by a spring 7 of the steel ball positioning device is matched with a positioning concave ring arranged on the outer wall of a sliding sleeve 9 to position the sliding sleeve 9, the shifting sleeve 11 is arranged in the sliding sleeve 9 in a matching way, and the shifting sleeve 11 rubs and drives the sliding sleeve 9. The shifting sleeve 11 is made of flexible wear-resistant and high-temperature-resistant materials. The upper end of the guide rod 13 is provided with a guide connector with a conical tip, the lower end of the guide rod 13 is provided with a screw rod, the guide rod 13 is sequentially provided with a lock sleeve 14, a locking spring 15, a locking nut and a reducing connecting pipe 17, the reducing connecting pipe 17 is locked through the locking nut, the locking spring 15 pushes up the lock sleeve 14, and a clamping jaw of the clamping spring 12 is locked with the guide connector of the guide rod 13. Piston ring grooves are uniformly distributed on the outer diameter cylindrical surface of the plunger 19, piston rings 20 are installed in the piston ring grooves in a matching mode, and sealing rings 18 are installed at the upper end and the lower end of the plunger 19 in a matching mode. The sealing ring 18 is a U-shaped sealing ring mounted back-to-back. The lower port of the fluid channel of the plunger 19 is connected with a locking sleeve 27 through threads, the inner wall of the tightening sleeve 27 is provided with a steel ball check valve seat 26 of a steel ball check valve device through an inner clamp spring 28 arranged in a clamp spring groove, a check steel ball 25 is matched with the steel ball check valve seat 26 and is higher than the locking sleeve of the upper part of the steel ball check valve seat 26, the upper end of the locking sleeve is matched with a plunger check valve seat 24 of the plunger check valve device, the upper part of the locking sleeve is a cone frustum, the lower part of the locking sleeve is a combination body with a cone tip to form a valve core 23, the cone tip cone surface of the locking sleeve is linearly sealed with the plunger check valve seat 24, the upper end of the cone frustum of the valve core is provided with a guide rod, a flow guide disc 21 arranged at the upper part of the fluid channel of the plunger through a reducing connecting pipe 17, the central guide hole of the flow guide disc is matched with the upper end of the guide rod provided with a check spring 22, and flow guide holes are uniformly distributed on the flow guide disc 21. The seal ring 18 is fitted in a seal ring groove formed by the upper end surface of the plunger 19 and the stopper of the reducing connecting pipe 17, and the seal ring 18 is fitted in a seal ring groove formed by the lower end surface of the plunger 19 and the stopper of the lock sleeve 27. A suction inlet check valve seat 31 of a suction inlet check valve device is arranged in a suction inlet pump sleeve 29 through a baffle table, a flow guide disc is arranged at the upper part of the suction inlet check valve seat 31 through a set spacing sleeve 30, the conical tip conical surface of a valve core 23 is linearly sealed with the suction inlet check valve seat 31, a guide rod provided with a check spring is arranged at the upper end of the valve core 23, and the upper end of the guide rod is matched with a central guide hole of the flow guide disc. The sealing length of the plunger 19 is 200 mm.

Claims

1. A short column stopper oil-well pump, characterized by: an oil pipe (1) is in threaded connection with a pump barrel (16) through an oil pipe coupling (3) and a transition connecting sleeve (5), the lower end of the pump barrel (16) is connected with a suction inlet pump sleeve (29), a sucker rod (2) in the pump barrel (16) is connected with a plunger assembly through a sucker rod coupling (4) and a connecting mechanism, an oil drainage hole (8) is arranged on the transition connecting sleeve (5), a sliding sleeve (9) matched with the oil drainage hole (8) is arranged in the transition connecting sleeve (5), the sliding sleeve (9) is positioned through a steel ball positioning device, the connecting mechanism consists of a grabbing spring (12), a guide rod (13) and a reducing connecting pipe (17) which are mutually matched and connected, wherein a poking sleeve (11) arranged on the grabbing spring connecting rod is matched with the sliding sleeve (9), a locking sleeve (14), a locking spring (15) and a locking nut (10) are arranged on the guide rod (13) with a guide connector at the upper end, the gripper of the gripper spring (12) is matched with a guide connector of a guide rod (13), the guide rod (13) is locked through a lock sleeve (14), the lower end of the guide rod (13) is connected with a reducing connecting pipe (17) with an oil outlet (32) through threads, a threaded pipe at the lower end of the guide rod is connected with a plunger assembly through threads, a piston ring (20) and a sealing ring (18) are installed outside a plunger (19) of the plunger assembly, a plunger check valve device is installed on a fluid channel in the plunger (19) in a matched mode, a steel ball check valve device is installed on the lower port of the fluid channel, and a suction inlet check valve device is installed in a suction inlet pump sleeve (29) in a matched mode.

2. The short plunger oil well pump of claim 1, wherein: the structure of grabbing spring (12) is setting up the grabhook of equipartition for the lower extreme at the connecting rod, the lower extreme of grabhook is setting up the frustum matched with card platform with the guide bar guiding connection head rear end, lock nut (10) and dial cover (11) are being installed in the cooperation on the connecting rod, lock nut (10) compress tightly sucker rod coupling (4), set up steel ball positioner on transitional coupling cover (5), steel ball (6) of its spring (7) control cooperate with the location concave ring that sets up on sliding sleeve (9) outer wall, fix a position sliding sleeve (9), dial cover (11) are being installed in sliding sleeve (9) fit, dial cover (11) friction drive sliding sleeve (9).

3. The short plug pump of claim 1 or 2, wherein: the shifting sleeve (11) is made of flexible wear-resistant and high-temperature-resistant materials.

4. The short plunger oil well pump of claim 1, wherein: the upper end of a guide rod (13) is provided with a guide connector with a conical tip, the lower end of the guide rod (13) is provided with a screw rod, a lock sleeve (14), a locking spring (15), a locking nut and a reducing connecting pipe (17) are sequentially arranged and installed on the guide rod (13), the reducing connecting pipe (17) is locked through the locking nut, the locking spring (15) pushes up the lock sleeve (14), and a clamping jaw of a grabbing spring (12) is locked with the guide connector of the guide rod (13).

5. The short plunger oil well pump of claim 1, wherein: piston ring grooves are uniformly distributed on the outer diameter cylindrical surface of the plunger (19), piston rings (20) are installed in the piston ring grooves in a matching mode, and sealing rings (18) are installed at the upper end and the lower end of the plunger (19) in a matching mode respectively.

6. The short plunger oil well pump of claim 5, wherein: the sealing ring (18) is a U-shaped sealing ring mounted back-to-back.

7. The short plunger oil well pump of claim 1, wherein: a locking sleeve (27) is connected in the lower port of a fluid channel of a plunger (19) through threads, a steel ball check valve seat (26) of a steel ball check valve device is arranged on the inner wall of the locking sleeve (27) through an inner clamp spring (28) arranged in a clamp spring groove, a check steel ball (25) is matched with the steel ball check valve seat (26), the locking sleeve is higher than the locking sleeve on the upper part of the steel ball check valve seat (26), the upper end of the locking sleeve is matched with a plunger check valve seat (24) of the plunger check valve device, the upper part of the locking sleeve is a cone frustum, the lower part of the locking sleeve is a combination body of the cone frustum to form a valve core (23), the cone frustum of the locking sleeve is linearly sealed with the plunger check valve seat (24), a guide rod is arranged on the upper end of the valve core cone frustum, a guide disc (21) is arranged on the upper part of the fluid channel of the plunger through a reducing connecting pipe (17), and the central guide hole of the guide rod is matched with the upper end of the guide rod provided with the check spring (22), the diversion disks (21) are uniformly provided with diversion holes.

8. The short plug pump of claim 5 or 7, wherein: a sealing ring (18) is arranged in a sealing ring groove formed by the upper end surface of the plunger (19) and the baffle table of the reducing connecting pipe (17) in a matching way, and the sealing ring (18) is arranged in a sealing ring groove formed by the lower end surface of the plunger (19) and the baffle table of the locking sleeve (27) in a matching way.

9. The short plunger oil well pump of claim 1, wherein: a suction inlet check valve seat (31) of a suction inlet check valve device is arranged in a suction inlet pump sleeve (29) through a baffle table, a flow guide disc is arranged at the upper part of the suction inlet check valve seat (31) through a set spacing sleeve (30), a conical pointed conical surface of a valve core (23) is linearly sealed with the suction inlet check valve seat (31), a guide rod provided with a check spring is arranged at the upper end of the valve core (23), and the upper end of the guide rod is matched with a central guide hole of the flow guide disc.

10. The short plunger oil well pump of claim 1, wherein: the sealing length of the plunger (19) is 200 mm.