A self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells

Abstract

This invention relates to the field of coalbed methane extraction equipment technology, and particularly to a self-repairing tubular oil pump for preventing clogging in coalbed methane wells. The pump includes: an upper coupling; a pump barrel with an exposed upper screen near the bottom, a limit ring on the inner wall of the barrel, and a primary and secondary locking assembly; a plunger inside the barrel; a downstream moving valve assembly, the top of which connects to the bottom of the plunger; and a feeding assembly including a sliding sleeve pusher, a secondary screen, a sliding sleeve, and a lower exposed screen. The top of the sliding sleeve pusher connects to the bottom of the downstream moving valve assembly, and the bottom of the sliding sleeve pusher has a primary locking claw that connects to the primary locking assembly. A scraping ring is provided on the side of the sliding sleeve and connects to the secondary locking assembly. A fixed valve assembly is located at the bottom of the lower exposed screen. This invention reduces the frequency of cleaning the tubular oil pump and lowers maintenance costs.

Description

Technical Field

[0001] This invention relates to the field of coalbed methane extraction equipment technology, and in particular to a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells. Background Technology

[0002] Coalbed methane (CBM), an important unconventional natural gas resource, is currently primarily extracted using a dewatering and depressurization process. This involves using pumps to remove water from the coal seam, reducing reservoir pressure and promoting CBM desorption and production. However, during deep CBM well extraction, the complex and brittle structure of the coal seam easily generates large amounts of coal dust and rock cuttings. The complex composition of the downhole fluid, with its high solid particle content, makes the fixed valve at the lower end of the pump highly susceptible to blockage or jamming due to the accumulation of fine particles, leading to a sharp drop in pump efficiency or even production stoppage.

[0003] Currently, the main methods for dealing with fixed valve blockage are well washing or well workover operations. Well washing requires additional equipment and the injection of large amounts of fluid, which is not only costly but may also cause secondary damage to the reservoir, and its effectiveness is limited, especially for severe blockages. Well workover operations, on the other hand, require the complete removal of the entire tubing string, which is expensive to repair and results in long downtime, seriously affecting production efficiency and economic benefits.

[0004] Therefore, there is a need for a pumping unit that can quickly and cost-effectively resolve the problem of fixed valve blockage without well workover operations. This would enable online valve replacement and channel reconstruction via surface operations after fixed valve failure, which has significant practical and engineering application value for improving the operational reliability of coalbed methane wells, reducing maintenance costs, and extending pump inspection cycles. Summary of the Invention

[0005] This invention aims to at least solve one of the technical problems existing in related technologies. To this end, this invention provides a self-repairing tubular oil pump for coalbed methane wells, which solves the technical problem that existing oil pumps require cleaning after the fixed valve becomes clogged before they can be used, thus reducing the number of cleaning operations and lowering maintenance costs.

[0006] This invention provides a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells, comprising: The upper coupling is used to connect the pumping unit, and the sucker rod of the pumping unit is located inside the upper coupling; The pump cylinder has its top end connected to the bottom end of the upper coupling. An upper exposed screen tube is formed near the bottom of the pump cylinder. A limit ring is provided on the inner wall of the pump cylinder, which is located below the upper exposed screen tube. A primary locking assembly and a secondary locking assembly are provided at intervals along the height direction on the inner wall of the pump cylinder, which are located above the upper exposed screen tube. A plunger is disposed inside the pump barrel, the top end of the plunger is connected to the sucker rod, and multiple floating valves are spaced apart inside the plunger; A downstream moving valve assembly is disposed inside the pump barrel, and the top of the downstream moving valve assembly can be connected to the bottom of the plunger; The feeding assembly includes a sliding sleeve pusher seat, a secondary screen tube, a sliding sleeve, and a lower exposed screen tube connected sequentially along the height direction. The top of the sliding sleeve pusher seat can be connected to the bottom of the downstream moving valve assembly. The primary locking assembly and the secondary locking assembly are located between the sliding sleeve pusher seat and the lower exposed screen tube. The bottom of the sliding sleeve pusher seat is provided with a primary locking claw, which can be connected to the primary locking assembly. The side of the sliding sleeve is provided with a scraping ring, which can be connected to the secondary locking assembly. The bottom of the lower exposed screen tube is provided with a fixed valve assembly.

[0007] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, is that the plunger is provided with a plurality of claw assemblies on the side wall near the bottom. The claw assembly includes a first claw with one end connected to the side wall of the plunger and a first spring connected between the first claw and the side wall of the plunger. The top inner wall of the downstream dynamic valve assembly is provided with a first slot, and the first claw is engaged in the first slot to connect the plunger and the downstream dynamic valve assembly.

[0008] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells, is that a locking buckle is provided at the bottom of the downstream dynamic valve assembly. The top of the sliding sleeve push seat is provided with an L-shaped second slot. The inner wall of the second slot is provided with a second spring. The second spring is connected to a first locking slider. The locking buckle can pass through the second slot and be locked to the first locking slider.

[0009] A further improvement of the present invention on a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well is that the sliding sleeve push seat includes a head section and a tail section, the inner diameters of the head section and the tail section are the same, the outer diameter of the head section is larger than the outer diameter of the tail section, the outer side wall of the head section is slidably disposed on the inner side wall of the pump barrel, the second slot is opened in the head section, and the first-stage locking claw is disposed at the bottom of the head section.

[0010] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells, is that the primary locking assembly includes: A first valve seat is connected to the inner wall of the pump cylinder, a third spring is connected to the first valve seat, and a second locking slider is connected to the third spring. The first-stage locking claw is engaged with the second locking slider.

[0011] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells, is that the first valve seat is provided with a jet nozzle, and the jet nozzle is arranged vertically.

[0012] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, is that the secondary locking assembly includes a second valve seat connected to the inner wall of the pump barrel, a fourth spring connected to the second valve seat, and a third locking slider connected to the fourth spring. The sliding sleeve includes an arc-shaped neck and a cylindrical body. A scraping ring is provided at the connection between the neck and the body. The scraping ring can be locked and connected to the third locking slider.

[0013] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells, is that the outer wall of the scraping ring is formed sequentially along the height direction with an arc-shaped ring portion, a third groove and a rectangular ring portion, and the third groove can be locked and connected to the third locking slider.

[0014] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, is that the bottom outer wall of the sliding sleeve protrudes outward to form a protrusion, the protrusion being located below the limiting ring, and the protrusion pressing against the limiting ring to restrict the upward movement of the sliding sleeve.

[0015] A further improvement of the present invention, a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, is that a plug-in portion is formed on the bottom inner wall of the pump barrel, and a plug-in section is formed on the side wall of the fixed valve assembly, the plug-in section being connected to the plug-in portion.

[0016] The self-repairing tubular oil pump for coalbed methane wells of this invention can replace the valve and rebuild the channel without well repair operations when the fixed valve becomes clogged or the seal is not tight. This is achieved simply by controlling the plunger stroke from the ground, significantly reducing maintenance costs and downtime. It also employs a multi-stage floating valve series design, coupled with a spring-locking mechanism in the first and second stage locking components, ensuring the stability and sealing of the valve after repair. Furthermore, the reversible operation of the self-repair function through the repeatable first and second stage locking components effectively improves the reusability of the oil pump, making it suitable for complex working conditions such as deep coalbed methane wells where coal dust is easily produced and blockages are common.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the segmented connection of a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention, in the first state.

[0020] Figure 2 This is a schematic diagram of the segmented connection of a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention, in the second state.

[0021] Figure 3 This is a schematic diagram of the segmented connection of a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention, in the third state.

[0022] Figure 4 This is a schematic diagram of the segmented connection of a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention, in the fourth state.

[0023] Figure 5 This is a partial schematic diagram of the downstream dynamic valve assembly of a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention.

[0024] Figure 6 This is a partial schematic diagram of the sliding sleeve push seat in a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention.

[0025] Figure 7 This is a partial schematic diagram of the downstream dynamic valve assembly of a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention, connected to the sliding sleeve push seat.

[0026] Figure 8 This is a schematic diagram of the plunger in a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention.

[0027] Figure 9 This is a schematic diagram of the sliding sleeve push seat, secondary screen pipe, lower exposed screen pipe and fixed valve assembly in a self-repairing tubular oil pump for preventing burial and blockage in a coalbed methane well, provided by the present invention.

[0028] Figure label: 1. Upper coupling; 2. Pump barrel; 3. Plunger; 4. First floating valve; 5. Second floating valve; 6. Claw assembly; 7. Downward floating valve assembly; 8. First locking slider; 9. Second spring; 10. Sliding sleeve pusher seat; 11. Secondary screen tube; 12. First valve seat; 13. Third spring; 14. Second locking slider; 15. Secondary locking assembly; 16. Upper exposed screen tube; 17. Sliding sleeve; 18. Lower exposed screen tube; 19. Fixed valve assembly; 20. Locking buckle; 21. Jet nozzle; 22. Scraper ring; 23. Sucker rod; 24. Limiting ring. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The following embodiments are used to illustrate this invention but should not be used to limit the scope of this invention.

[0030] The following is combined with Figures 1 to 9 The present invention describes a self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells, comprising: Upper coupling 1 is used to connect the oil pumping unit, and the sucker rod 23 of the oil pumping unit is located inside the upper coupling 1; Pump cylinder 2, the top end of which is connected to the bottom end of the upper coupling 1, an upper exposed screen tube 16 is formed near the bottom of the pump cylinder 2, a limiting ring 24 is provided on the inner wall of the pump cylinder 2, the limiting ring 24 is located below the upper exposed screen tube 16, and a primary locking assembly and a secondary locking assembly 15 are provided at intervals along the height direction on the inner wall of the pump cylinder 2, the primary locking assembly and the secondary locking assembly 15 are located above the upper exposed screen tube 16; A plunger 3 is disposed inside the pump barrel 2, the top end of the plunger 3 is connected to the sucker rod 23, and multiple floating valves are spaced apart inside the plunger 3; Downstream moving valve assembly 7, which is disposed inside the pump cylinder 2, wherein the top of the downstream moving valve assembly 7 can be connected to the bottom of the plunger 3; The feeding assembly includes a sliding sleeve push seat 10, a secondary screen tube 11, a sliding sleeve 17, and a lower exposed screen tube 18 connected sequentially along the height direction. The top of the sliding sleeve push seat 10 can be connected to the bottom of the downstream moving valve assembly 7. The primary locking assembly and the secondary locking assembly 15 are located between the sliding sleeve push seat 10 and the lower exposed screen tube 18. The bottom of the sliding sleeve push seat 10 is provided with a primary locking claw, which can be connected to the primary locking assembly. The side of the sliding sleeve 17 is provided with a scraping ring 22, which can be connected to the secondary locking assembly 15. The bottom of the lower exposed screen tube 18 is provided with a fixed valve assembly 19.

[0031] Furthermore, the plunger 3 is provided with a plurality of claw assemblies 6 on its side wall near the bottom. Each claw assembly 6 includes a first claw with one end connected to the side wall of the plunger 3 and a first spring connected between the first claw and the side wall of the plunger 3. The top inner side wall of the downstream moving valve assembly 7 is provided with a first slot, and the first claw is engaged in the first slot to connect the plunger 3 and the downstream moving valve assembly 7.

[0032] Preferably, the plunger 3 has a first step and a second step formed on the side wall near the bottom along the height direction, the top of the first pawl is connected to the side wall of the first step of the plunger 3 through a pivot, and the first spring is connected to the second step.

[0033] Furthermore, the bottom of the downstream moving valve assembly 7 is provided with a locking buckle 20; the top of the sliding sleeve push seat 10 is provided with an L-shaped second slot, the inner wall of the second slot is provided with a second spring 9, the second spring 9 is connected to a first locking slider 8, and the locking buckle 20 can pass through the second slot and be locked and connected to the first locking slider 8.

[0034] Preferably, the second spring 9 and the first locking slider 8 are arranged horizontally.

[0035] Specifically, the sliding sleeve push seat 10 includes a head section and a tail section. The inner diameters of the head section and the tail section are the same, and the outer diameter of the head section is larger than the outer diameter of the tail section. The outer side wall of the head section is slidably disposed on the inner side wall of the pump cylinder 2. The second slot is opened in the head section, and the first-stage locking claw is disposed at the bottom of the head section.

[0036] Furthermore, the primary locking assembly includes a first valve seat 12 connected to the inner wall of the pump cylinder 2, a third spring 13 connected to the first valve seat 12, and a second locking slider 14 connected to the third spring 13, wherein the primary locking claw engages with the second locking slider 14.

[0037] Specifically, the top of the first valve seat 12 is provided with an L-shaped fourth slot, and the third spring 13 and the second locking slider 14 are horizontally disposed in the fourth slot.

[0038] Specifically, the first valve seat 12 is provided with a jet nozzle 21, which is arranged vertically.

[0039] Preferably, an annular cavity is formed between the secondary screen tube 11 and the inner wall of the pump barrel 2 or the upper exposed screen tube 16. When the feeding assembly moves along the height direction, the liquid in the annular cavity can be pressurized and sprayed through the jet nozzle 21, thereby facilitating the cleaning of blockages in the annular cavity and ensuring that the secondary screen tube 11 can move stably in the pump barrel.

[0040] Specifically, the secondary locking assembly 15 includes a second valve seat connected to the inner wall of the pump cylinder 2, a fourth spring connected to the second valve seat, and a third locking slider connected to the fourth spring; the sliding sleeve 17 includes an arc-shaped neck and a cylindrical body, and a scraping ring 22 is provided at the connection position between the neck and the body, and the scraping ring 22 can be locked and connected to the third locking slider.

[0041] Preferably, the fourth spring and the third locking slider are arranged horizontally.

[0042] Specifically, the outer wall of the scraping ring 22 is formed with an arc-shaped ring, a third slot and a rectangular ring in sequence along the height direction, and the third slot can be locked and connected to the third locking slider.

[0043] Specifically, the bottom outer wall of the sliding sleeve 17 protrudes outward to form a protrusion, which is located below the limiting ring 24. The protrusion presses against the limiting ring 24 to restrict the upward movement of the sliding sleeve 17.

[0044] Specifically, the bottom inner wall of the pump cylinder 2 has a plug-in portion, and the side wall of the fixed valve assembly 19 has a plug-in section, which is connected to the plug-in portion.

[0045] Preferably, a first floating valve 4 and a second floating valve 5 are provided inside the plunger 3 along the height direction.

[0046] The initial state is normal production state, such as Figure 1 As shown, the plunger 3 reciprocates under the drive of the sucker rod 23, which drives the first moving valve 4, the second moving valve 5 and the downstream moving valve assembly 7 to move synchronously. The fluid enters the pump barrel 2 through the fixed valve assembly 19 and is discharged through the first moving valve 4, the second moving valve 5 and the downstream moving valve assembly, thus realizing drainage and gas extraction.

[0047] When the fixed valve assembly 19 becomes blocked or jammed due to coal seam accumulation, fluid cannot enter the pump cylinder 2, and the pump efficiency is significantly reduced. At this time, by adjusting the pumping unit parameters, the plunger 3 and the downstream moving valve assembly 7 continue to descend beyond the normal operating bottom dead center until the locking buckle 20 at the lower end of the downstream moving valve assembly 7 is locked by the second spring 9 and the first locking slider 8, so that the downstream moving valve assembly 7 is connected to the sliding sleeve push seat 10 as one unit; subsequently, as Figure 3 As shown, the downward thrust of the plunger 3 causes the third locking slider of the resettable secondary locking assembly 15 to retract, unlocking the sliding sleeve 17; the downward thrust of the downstream moving valve assembly 7 pushes the sliding sleeve pusher seat 10 and the sliding sleeve 17 downward, and the previously obscured upper exposed screen pipe 16 and lower exposed screen pipe 18 gradually connect with the formation. Since the installation position of the upper exposed screen pipe 16 and lower exposed screen pipe 18 is higher than that of the fixed valve assembly 19, they are located above the coal seam plugging layer, forming a new clean liquid inlet channel, facilitating the continued drainage and gas production; as Figure 4 As shown, the plunger 3 moves downward, pushing the downstream moving valve assembly 7 downward until the first-stage locking pawl of the sliding sleeve push seat 10 enters the first valve seat 12 and locks with the third spring 13 and the second locking slider 14, preventing the downstream moving valve assembly from resetting; subsequently, as... Figure 2 As shown, the plunger 3 is slowly moved upward by the operation of the sucker rod 23. Since the downstream moving valve assembly 7 is locked, the upward pulling force releases the chuck assembly 6, and the downstream moving valve assembly 7 disengages from the plunger 3. At this time, the downstream moving valve assembly 7 and the feed assembly form a new fixed valve structure to restore normal production. After the normal production state is restored, the sucker rod 23 drives the plunger 3 to reciprocate, which drives the first moving valve 4 and the second moving valve 5 to move synchronously. The fluid no longer enters from the fixed valve assembly 19 which is buried at the bottom, but enters the pump barrel 2 through the newly exposed upper exposed screen pipe 16, lower exposed screen pipe 18 and secondary screen pipe 11 via the downstream moving valve assembly 7, and is discharged through the first moving valve 4 and the second moving valve 5 to achieve drainage and gas production. The whole process does not require pulling out the tubing or performing well workover operations.

[0048] When the downstream moving valve assembly 7 becomes clogged again or the unit needs to be restored to its initial state, the stroke of the pumping unit is adjusted so that the plunger 3 descends beyond the self-repair position to the contact position. The claw assembly 6 then re-engages the downstream moving valve assembly 7, restoring the initial connection between the plunger 3 and the downstream moving valve assembly 7. Subsequently, the plunger 3 is lifted, causing the sliding sleeve push seat 10 and the sliding sleeve 17 to move upward, triggering the second locking slider 14 of the second valve seat and the first-stage locking claw to unlock. The second locking slider 14 retracts, releasing the sliding sleeve push seat 10. The plunger 3 is then lifted further. Until the secondary locking assembly 15 is reset, the sliding sleeve 17 moves upward back to its initial position, and the upper exposed screen pipe 16 and the lower exposed screen pipe 18 are covered again; the plunger 3 continues to move upward, and the locking buckle 20 triggers the first locking slider 8 of the sliding sleeve push seat 10 and the locking buckle 20 to unlock, causing the first locking slider 8 to retract, thereby releasing the downstream moving valve assembly 7 and restoring it to its initial state; at this time, the fixed valve assembly 19 becomes the fluid inlet channel again, and the surrounding accumulation can be cleaned by short-term well flushing or large-stroke operation, the device returns to its initial state, and normal production can continue.

[0049] The self-repairing tubular oil pump for coalbed methane wells of this invention can replace the valve and rebuild the channel without well repair operations when the fixed valve becomes blocked or the seal is not tight. This is achieved simply by controlling the plunger stroke 3 from the ground, significantly reducing maintenance costs and downtime. It also employs a multi-stage floating valve series design, coupled with a spring locking mechanism of the first-stage and second-stage locking components 15, ensuring the stability and sealing of the valve after repair. Furthermore, the reversible operation of the self-repair function is achieved through the repeatable first-stage and second-stage locking components 15, effectively improving the reusability of the oil pump. This makes it suitable for complex working conditions such as deep coalbed methane wells where coal dust is easily produced and blockages are common.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-repairing pipe type oil well pump for preventing burying and blocking of a coal bed gas well, characterized in that, include: The upper coupling is used to connect the pumping unit, and the sucker rod of the pumping unit is located inside the upper coupling; The pump cylinder has its top end connected to the bottom end of the upper coupling. An upper exposed screen tube is formed near the bottom of the pump cylinder. A limit ring is provided on the inner wall of the pump cylinder, which is located below the upper exposed screen tube. A primary locking assembly and a secondary locking assembly are provided at intervals along the height direction on the inner wall of the pump cylinder, which are located above the upper exposed screen tube. A plunger is disposed inside the pump barrel, the top end of the plunger is connected to the sucker rod, and multiple floating valves are spaced apart inside the plunger; A downstream moving valve assembly is disposed inside the pump barrel, and the top of the downstream moving valve assembly can be connected to the bottom of the plunger; The feeding assembly includes a sliding sleeve pusher seat, a secondary screen tube, a sliding sleeve, and a lower exposed screen tube connected sequentially along the height direction. The top of the sliding sleeve pusher seat can be connected to the bottom of the downstream moving valve assembly. The primary locking assembly and the secondary locking assembly are located between the sliding sleeve pusher seat and the lower exposed screen tube. The bottom of the sliding sleeve pusher seat is provided with a primary locking claw, which can be connected to the primary locking assembly. The side of the sliding sleeve is provided with a scraping ring, which can be connected to the secondary locking assembly. The bottom of the lower exposed screen tube is provided with a fixed valve assembly.

2. The self-repairing pipe type oil well pump for preventing burying and plugging of coal bed gas well according to claim 1, characterized in that, The plunger has a plurality of claw assemblies on its side wall near the bottom. Each claw assembly includes a first claw with one end connected to the side wall of the plunger and a first spring connected between the first claw and the side wall of the plunger. The top inner wall of the downstream dynamic valve assembly is provided with a first slot, and the first claw is engaged in the first slot to connect the plunger and the downstream dynamic valve assembly.

3. The self-repairing pipe pump for coal bed gas well according to claim 1, characterized in that, The bottom of the downstream valve assembly is provided with a locking buckle; The top of the sliding sleeve push seat is provided with an L-shaped second slot. The inner wall of the second slot is provided with a second spring. The second spring is connected to a first locking slider. The locking buckle can pass through the second slot and be locked to the first locking slider.

4. The self-repairing pipe type oil well pump for preventing burying and plugging of coal bed gas well according to claim 3, characterized in that, The sliding sleeve push seat includes a head section and a tail section. The head section and the tail section have the same inner diameter. The outer diameter of the head section is larger than the outer diameter of the tail section. The outer side wall of the head section is slidably disposed on the inner side wall of the pump cylinder. The second slot is opened in the head section. The first-stage locking claw is disposed at the bottom of the head section.

5. The self-repairing pipe pump for coal bed gas well according to claim 1, characterized in that, The primary locking assembly includes: A first valve seat is connected to the inner wall of the pump cylinder, a third spring is connected to the first valve seat, and a second locking slider is connected to the third spring. The first-stage locking claw is engaged with the second locking slider.

6. The self-repairing pipe pump for coal bed gas well according to claim 5, characterized in that, The first valve seat is provided with a jet nozzle, which is arranged vertically.

7. A self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells according to claim 1, characterized in that, The secondary locking assembly includes a second valve seat connected to the inner wall of the pump cylinder, a fourth spring connected to the second valve seat, and a third locking slider connected to the fourth spring; The sliding sleeve includes an arc-shaped neck and a cylindrical body. A scraping ring is provided at the connection between the neck and the body. The scraping ring can be locked and connected to the third locking slider.

8. A self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells according to claim 7, characterized in that, The outer wall of the scraping ring is formed sequentially along the height direction by an arc-shaped ring portion, a third slot, and a rectangular ring portion. The third slot can be engaged with the third locking slider.

9. A self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells according to claim 1, characterized in that, The bottom outer wall of the sliding sleeve protrudes outward to form a protrusion. The protrusion is located below the limiting ring and presses against the limiting ring to restrict the upward movement of the sliding sleeve.

10. A self-repairing tubular oil pump for preventing burial and blockage in coalbed methane wells according to claim 1, characterized in that, The bottom inner wall of the pump cylinder has a plug-in portion, and the side wall of the fixed valve assembly has a plug-in section, which is connected to the plug-in portion.

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