Horizontal well linear motor pump

Abstract

The present invention discloses a horizontal well linear motor pump, which belongs to the field of oil extraction equipment. The horizontal well linear motor pump comprises a bridge pipe, the top of the bridge pipe is fixedly connected to an oil pipe interface, the inner wall of the bridge pipe is provided with an upper pump barrel, the inner cavity of the upper pump barrel is provided with an upper plunger, the top of the upper pump barrel is provided with a fixed valve, the inner cavity of the bridge pipe is provided with a lower pump barrel near the lower side, the inner cavity of the lower pump barrel is provided with a lower plunger, the inner cavity of the lower plunger and the top of the upper plunger are respectively provided with a swimming valve, an annular cavity is reserved between the lower pump barrel and the lower plunger, the side wall of the annular cavity is provided with an annular cavity oil outlet, the side wall of the lower plunger is provided with a pump body oil inlet near the bottom end, and the bottom end of the lower plunger is provided with a plunger rotator, which can realize the use of a large and small pump series structure, and discharge oil into the oil pipe cavity during the up and down strokes, thereby realizing the function of a double-acting pump. Compared with an ordinary series pump that only discharges oil from the annular cavity in a single stroke, the displacement of this pump is larger.

Description

Technical Field

[0001] The present invention relates to the field of oil extraction equipment, and more particularly to a horizontal well linear motor pump. Background Art

[0002] Linear motor pumping systems offer greater efficiency and energy savings than traditional beam pumping systems, and have garnered increasing attention and attention in oilfields in recent years. This system primarily involves connecting a linear motor to a well pump, which is installed at a designated location downhole. The motor's power propels the pump's piston, completing the pumping operation. Compared to the traditional surface beam pumping system, which drives the downhole pump, this system eliminates the need for rods, enabling rodless oil production. As a key component of this system, linear motor pumps have emerged in various configurations, and their technology continues to evolve and improve.

[0003] Due to the influence of various geological environments, many oil wells in oil fields are not completely vertical, but have large well inclinations, and even reach horizontal states. Conventional linear motor oil pumps in horizontal wells are affected by gravity, resulting in problems such as the valve ball and valve seat being unable to be aligned, delayed closing, and side leakage. In addition, due to the action of gravity, the movement trajectory of the plunger in the pump barrel is fixed, and the plunger pump barrel often suffers from eccentric wear and pump jamming. The above situations will lead to low pump efficiency or even no pump efficiency, and frequent well repair operations have to be carried out during construction, which not only increases the labor intensity of construction personnel, but also further affects the economic benefits of oil production companies. For this reason, a new type of pump that can be used in horizontal wells in conjunction with linear motors is needed to meet production needs. Summary of the Invention

[0004] 1. Technical problems to be solved

[0005] In response to the problems existing in the prior art, the purpose of the present invention is to provide a horizontal well linear motor pump, which can be realized by installing a plunger rotation device on the plunger so that the plunger can be pushed by the motor for linear motion while being able to rotate axially in a regular manner. In this way, in the horizontal state, the outer cylindrical surface of the plunger will not press the pump barrel in a fixed position, thereby avoiding eccentric wear between the pump barrel and the plunger and extending the service life of the pump.

[0006] 2. Technical solution

[0007] To solve the above problems, the present invention adopts the following technical solutions.

[0008] A horizontal well linear motor pump includes a bridge pipe, the top of the bridge pipe is fixedly connected to an oil pipe interface, an upper pump barrel is provided on the inner wall of the bridge pipe, an upper plunger is installed in the inner cavity of the upper pump barrel, a fixed valve is provided on the top of the upper pump barrel, a lower pump barrel is installed near the lower side of the inner cavity of the bridge pipe, a lower plunger is installed in the inner cavity of the lower pump barrel, a floating valve is provided in the inner cavity of the lower plunger and the top of the upper plunger respectively, an annular cavity is reserved between the lower pump barrel and the lower plunger, an annular cavity oil outlet is provided on the side wall of the annular cavity, a pump body oil inlet is provided on the side wall of the lower plunger near the bottom end, and a plunger rotator is provided at the bottom end of the lower plunger.

[0009] Furthermore, the fixed valve includes a valve seat, which is fixedly connected to the top of the upper pump barrel, and a valve cover is fixedly connected to the side wall of the valve seat. The top of the valve seat is movably connected to a guide rod, and the bottom end of the guide rod extends to the inner cavity of the valve cover and is fixedly connected to a valve ball. The side wall of the guide rod is located in the inner cavity of the valve cover and is provided with a first spring.

[0010] Furthermore, the floating valve includes a connecting seat, which is fixedly connected to the top of the upper piston and the inner wall of the lower piston respectively. The top of the upper connecting seat is movably connected to a vertical rod, and the bottom end of the vertical rod passes through the lower connecting seat and is fixedly connected to a sealing ball. The side wall of the vertical rod is located between the connecting seats on both sides and is sleeved with a second spring.

[0011] Furthermore, the plunger rotator includes a connecting shaft, which is installed at the bottom end of the lower plunger. The side wall of the connecting shaft is movably connected to a sleeve, and the side wall of the sleeve is symmetrically movably connected to two pins. The side wall of the connecting shaft is provided with a corrugated track, which is arranged in a ring shape. The pin is inserted into the corrugated track, and a connecting component is provided at the bottom end of the sleeve.

[0012] Furthermore, the connecting assembly includes a motor connector, and two clamping blocks are symmetrically fixedly connected to the side wall of the motor connector near the top. Two clamping grooves are provided on the bottom end surface of the sleeve, and the clamping blocks and the clamping grooves match each other.

[0013] Furthermore, the upper pump barrel, the lower plunger and the side wall of the sleeve are all fixedly connected with a centering positioning block, and the centering positioning blocks are all against the inner wall of the bridge pipe.

[0014] Furthermore, a plurality of sieve holes are provided on the side wall of the bridge pipe near the bottom end, and the sieve holes are located on the sleeve.

[0015] Furthermore, the sealing ball abuts against the end surface of the connecting seat.

[0016] 3. Beneficial effects

[0017] Compared with the prior art, the advantages of the present invention are:

[0018] (1) This technical solution adopts a series structure of large and small pumps. During the up and down strokes, oil is discharged into the oil pipe cavity, realizing the function of a double-acting pump. Compared with the ordinary series pump that only discharges oil from the annular cavity in a single stroke, the displacement of this pump is larger.

[0019] (2) In ordinary linear motor pumps, the valve ball moves in the valve housing, relying on its own gravity and liquid pressure to open and close. Therefore, ordinary linear motor pumps can only be used in vertical wells, and the ball valve can work properly. The ball valve in this solution has a guide rod and spring to control the movement trajectory of the valve ball. Therefore, even if the pump body is in a horizontal position, the ball valve can open and close normally. Therefore, this type of linear motor pump can work in horizontal wells.

[0020] (3) Ordinary linear motor pumps are used in vertical wells. The plunger reciprocates in the pump barrel. The clearance between the plunger and the pump barrel is reasonable and the force is evenly distributed. If used in horizontal wells, the plunger will press the pump barrel due to its own weight, causing severe local flat wear during reciprocating motion. In this solution, a plunger rotation device is installed on the plunger, so that the plunger can rotate axially in a regular manner while being pushed by the motor to move linearly. In this way, the outer cylindrical surface of the plunger will not press the pump barrel at a fixed position in the horizontal state, thus avoiding uneven wear between the pump barrel and the plunger and extending the service life of the pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of the present invention;

[0022] Figure 2 It is a structural schematic diagram of the fixed valve in the present invention;

[0023] Figure 3 Schematic diagram of the structure of the plunger rotator in the present invention;

[0024] Figure 4 For the present invention Figure 1 A magnified view of point A in the figure;

[0025] Figure 5 It is a schematic diagram of the front structure of the corrugated track in the present invention.

[0026] Description of the numbers in the figure:

[0027] 1. Bridge pipe; 2. Oil pipe interface; 3. Upper pump barrel; 4. Upper plunger; 5. Fixed valve; 6. Valve seat; 7. Valve cover; 8. Guide rod; 9. Valve ball; 10. First spring; 11. Connecting seat; 12. Vertical rod; 13. Second spring; 14. Sealing ball; 15. Oil outlet of annular cavity; 16. Lower pump barrel; 17. Lower plunger; 18. Annular cavity; 19. Oil inlet of pump body; 20. Coupling shaft; 21. Sleeve; 22. Pin; 23. Corrugated track; 24. Slot; 25. Motor connector; 26. Block; 27. Sieve hole; 28. Straightening and positioning block. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] Example 1:

[0030] See also Figure 1-5 , a horizontal well linear motor pump includes a bridge pipe 1, the top of the bridge pipe 1 is fixedly connected to an oil pipe interface 2, an upper pump barrel 3 is provided on the inner wall of the bridge pipe 1, an upper plunger 4 is installed in the inner cavity of the upper pump barrel 3, a fixed valve 5 is provided on the top of the upper pump barrel 3, a lower pump barrel 16 is installed near the lower side of the inner cavity of the bridge pipe 1, a lower plunger 17 is installed in the inner cavity of the lower pump barrel 16, a swimming valve is provided in the inner cavity of the lower plunger 17 and the top of the upper plunger 4 are respectively provided with a ring valve, an annular cavity 18 is reserved between the lower pump barrel 16 and the lower plunger 17, an annular cavity oil outlet 15 is provided on the side wall of the annular cavity 18, a pump body oil inlet 19 is provided on the side wall of the lower plunger 17 near the bottom end, and a plunger rotator is provided at the bottom end of the lower plunger 17. A large and small pump series structure is adopted. Oil is discharged to the oil pipe cavity during the up and down strokes to realize the function of a double-acting pump. Compared with the ordinary series pump which only discharges oil from the single-stroke annular cavity 18, the displacement of this pump is larger.

[0031] See Figure 2 The fixed valve 5 includes a valve seat 6, which is fixedly connected to the top of the upper pump cylinder 3. A valve cover 7 is fixedly connected to the side wall of the valve seat 6. A guide rod 8 is movably connected to the top of the valve seat 6. The bottom end of the guide rod 8 extends to the inner cavity of the valve cover 7 and is fixedly connected to a valve ball 9. The side wall of the guide rod 8 is located in the inner cavity of the valve cover 7 and is sleeved with a first spring 10.

[0032] In an ordinary linear motor pump, the valve ball 9 swims in the valve cover 7, and is opened and closed by its own gravity and liquid pressure; therefore, an ordinary linear motor pump can only be used in a vertical well for the valve ball 9 to work properly; in this solution, the valve ball 9 has a guide rod 8 and a first spring 10 to control the movement trajectory of the valve ball 9, so even if the pump body is in a horizontal position, the valve ball 9 can be opened and closed normally, so this type of linear motor pump can work in a horizontal well.

[0033] See Figure 4 The floating valve includes a connecting seat 11, which is fixedly connected to the top of the upper plunger 4 and the inner wall of the lower plunger 17 respectively. The top of the upper connecting seat 11 is movably connected to a vertical rod 12. The bottom end of the vertical rod 12 passes through the lower connecting seat 11 and is fixedly connected to a sealing ball 14. The sealing ball 14 is against the end face of the connecting seat 11. The side wall of the vertical rod 12 is located between the connecting seats 11 on both sides and is sleeved with a second spring 13.

[0034] Among them, the structure of the floating valve is similar to that of the fixed valve 5. The connecting seat 11 belongs to the internal structure of the valve cover 7, and the vertical rod 12, sealing ball 14 and second spring 13 are all installed inside the valve cover 7. The floating valve is installed as a whole between the upper plunger 4 and the lower plunger 17.

[0035] The fixed valve 5 and the floating valve have similar structures and the same working principles; a guide device consisting of a guide rod 8, a first spring 10 and a second spring 13 is installed inside the valve cover 7; the guide rod 8 controls the opening and closing movement direction of the valve ball 9, and the compression force of the first spring 10 and the second spring 13 helps the valve ball 9 to close quickly. Under the dual action of the guide rod 8 and the first spring 10 or the second spring 13, the valve ball 9 and the valve seat 6 are centered and sealed well, opening and closing are faster, reducing the adverse effect of gravity on the opening and closing of the valve ball 9 in the horizontal state, ensuring the normal operation of the pump valve.

[0036] See Figure 3 The plunger rotator includes a coupling 20, which is installed at the bottom end of the lower plunger 17. The side wall of the coupling 20 is movably connected to a sleeve 21. The side wall of the sleeve 21 is symmetrically movably connected to two pins 22. A corrugated track 23 is provided on the side wall of the coupling 20. The corrugated track 23 is arranged in a ring shape. The pin 22 is inserted into the corrugated track 23. A connecting component is provided at the bottom end of the sleeve 21. A plurality of sieve holes 27 are provided near the bottom end of the side wall of the bridge pipe 1. The sieve holes 27 are located at the sleeve 21.

[0037] Among them, the plunger rotator is connected by a connecting shaft 20 and a sleeve 21 hanging sleeve. The outer surface of the connecting shaft 20 is designed with a circumferential corrugated track 23. A pin 22 is fixed on the sleeve 21, and the pin 22 is embedded in the corrugated track 23 on the connecting shaft 20. When the motor pushes the plunger assembly to move axially, the pin 22 will move along the corrugated track 23. Every time the pin 22 moves from the peak of the wave line trajectory to the bottom of the valley, the plunger assembly will be forced to rotate 45°. In this way, the plunger assembly can rotate regularly in a horizontal state, avoiding the upper plunger 4 and the lower plunger 17 from being pressed by the fixed position of the outer cylindrical surface due to gravity on the inner hole surface of the upper pump barrel 3 and the lower pump barrel 16 to form eccentric wear.

[0038] Ordinary linear motor pumps are used in vertical wells. The plunger reciprocates in the pump barrel. The gap between the plunger and the pump barrel is reasonable and the force is evenly distributed. If used in horizontal wells, the plunger will press the pump barrel due to its own weight, causing serious local flat wear during reciprocating motion. In this solution, a plunger rotation device is installed on the plunger, so that the plunger can rotate axially in a regular manner while being pushed by the motor for linear motion. In this way, in a horizontal state, the outer cylindrical surface of the plunger will not press the pump barrel in a fixed position, thereby avoiding uneven wear between the pump barrel and the plunger and extending the service life of the pump.

[0039] See Figure 3The connecting component includes a motor connector 25. Two blocks 26 are symmetrically fixedly connected to the side wall of the motor connector 25 near the top. Two slots 24 are provided on the bottom end face of the sleeve 21. The blocks 26 match the slots 24. The lower part of the sleeve 21 in the plunger rotator is designed with a slot 24. When installing the motor, you only need to directly hang the corresponding motor connector 25, which is convenient for removal. After the motor connector 25 is hung in the slot 24, the circular rotation is not restricted. Therefore, when the plunger rotator drives the plunger assembly to rotate, it will not reversely affect the rotation of the motor.

[0040] See Figure 1 The upper pump barrel 3, the lower plunger 17 and the side walls of the sleeve 21 are fixedly connected with the straightening and positioning blocks 28, and the straightening and positioning blocks 28 are all against the inner wall of the bridge pipe 1. The straightening and positioning blocks 28 are designed on the connecting parts at different positions of the pump body to help the inner and outer pipes to be horizontally installed without local collapse, ensuring the concentricity between the upper pump barrel 3, the lower pump barrel 16, the bridge pipe 1 and the sieve hole 27.

[0041] In use: During the downstroke, the linear motor drags the entire plunger downward, the chamber space between the plunger and the fixed valve 5 increases, forming a low-pressure chamber, the fixed valve 5 closes, the floating valve opens, and crude oil enters the pump barrel through the oil inlet 19 of the pump body, while the annular chamber 18 discharges oil outward;

[0042] During the upward stroke, the chamber space between the plunger and the fixed valve 5 decreases, forming a high-pressure chamber. The fixed valve 5 opens, the floating valve closes, and the oil in the pump barrel rises to the oil pipe above the fixed valve 5 and is gradually lifted to the ground, completing the oil production process.

[0043] When the linear motor pump is working, it is in a nearly horizontal state. Therefore, a guide rod 8 and a first spring 10 are installed on each set of valve balls 9. Each opening and closing of the valve ball 9 can only follow the restraining direction of the guide rod 8, ensuring that the valve ball 9 and the valve seat 6 are well aligned. The first spring 10 uses the compression force to enable the valve ball 9 to close quickly. Under the dual action of the guide rod 8 and the first spring 10, it can ensure that the valve ball 9 is well sealed and works normally.

[0044] In addition, the coupling 20 of the plunger rotator is connected to the sleeve 21, and the outer surface of the coupling 20 is designed with a circumferential wave track 23. The pin 22 on the sleeve 21 is embedded in the wave track 23. When the motor pushes the plunger to move axially, the pin 22 will move along the wave track 23. Every time the pin 22 moves from the peak of the wave track to the bottom of the valley, the plunger will be forced to rotate 45°. In this way, the plunger can be kept in a horizontal state, avoiding the fixed position of the outer cylindrical surface of the plunger due to gravity pressing on the inner hole surface of the pump barrel to cause eccentric wear.

[0045] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto. Any person skilled in the art who, within the technical scope disclosed by the present invention, makes equivalent substitutions or modifications based on the technical solutions and improved concepts of the present invention shall be covered by the scope of protection of the present invention.

Claims

1. A horizontal well linear motor pump, comprising a bridge pipe (1), characterized in that: The top of the bridge pipe (1) is fixedly connected to an oil pipe interface (2), an upper pump barrel (3) is provided on the inner wall of the bridge pipe (1), an upper plunger (4) is installed in the inner cavity of the upper pump barrel (3), a fixed valve (5) is provided on the top of the upper pump barrel (3), a lower pump barrel (16) is installed near the lower side of the inner cavity of the bridge pipe (1), a lower plunger (17) is installed in the inner cavity of the lower pump barrel (16), a floating valve is provided in the inner cavity of the lower plunger (17) and the top of the upper plunger (4), an annular cavity (18) is reserved between the lower pump barrel (16) and the lower plunger (17), an annular cavity (18) is provided on the side wall of the annular cavity (18), a pump body oil inlet (19) is provided on the side wall of the lower plunger (17) near the bottom end, and a plunger rotator is provided at the bottom end of the lower plunger (17); The fixed valve (5) includes a valve seat (6), the valve seat (6) is fixedly connected to the top of the upper pump barrel (3), the side wall of the valve seat (6) is fixedly connected to a valve cover (7), the top of the valve seat (6) is movably connected to a guide rod (8), the bottom end of the guide rod (8) extends to the inner cavity of the valve cover (7) and is fixedly connected to a valve ball (9), and the side wall of the guide rod (8) is located in the inner cavity of the valve cover (7) and is provided with a first spring (10); The floating valve arranged in the inner cavity of the lower plunger (17) includes a connecting seat (11), the connecting seat (11) is fixedly connected to the inner wall of the lower plunger (17), the top end of the upper connecting seat (11) is movably connected to a vertical rod (12), the bottom end of the vertical rod (12) passes through the lower connecting seat (11) and is fixedly connected to a sealing ball (14), and the side wall of the vertical rod (12) is located between the connecting seats (11) on both sides and is sleeved with a second spring (13).

2. The horizontal well linear motor pump according to claim 1, characterized in that: The plunger rotator comprises a connecting shaft (20), the connecting shaft (20) being mounted on the bottom end of the lower plunger (17), the side wall of the connecting shaft (20) being movably connected to a sleeve (21), the side wall of the sleeve (21) being symmetrically movably connected to two pins (22), the side wall of the connecting shaft (20) being provided with a corrugated track (23), the corrugated track (23) being arranged in an annular shape, the pins (22) being inserted into the corrugated track (23), and the bottom end of the sleeve (21) being provided with a connecting assembly.

3. The horizontal well linear motor pump according to claim 2, characterized in that: The connecting assembly comprises a motor connector (25), two clamping blocks (26) are symmetrically fixedly connected to the side wall of the motor connector (25) near the top, and two clamping grooves (24) are provided on the bottom end surface of the sleeve (21), and the clamping blocks (26) and the clamping grooves (24) match each other.

4. The horizontal well linear motor pump according to claim 3, characterized in that: The upper pump barrel (3), the lower plunger (17) and the side walls of the sleeve (21) are all fixedly connected with a centering positioning block (28), and the centering positioning block (28) is in contact with the inner wall of the bridge pipe (1).

5. The horizontal well linear motor pump according to claim 4, characterized in that: A plurality of sieve holes (27) are provided on the side wall of the bridge pipe (1) near the bottom end, and the sieve holes (27) are located on the sleeve (21).

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