Self-cleaning anti-jamming oil pump

Abstract

This utility model belongs to the field of oil pump technology and discloses a self-cleaning anti-jamming oil pump, including a pump barrel and a plunger. The plunger and pump barrel are clearance-fitted. A spiral groove is formed on the inner wall of the pump barrel. The spiral groove is located within the stroke range of the plunger's reciprocating motion, and the axial length of the plunger is greater than the axial length of the spiral groove. This allows the spiral groove to not only accommodate solid particles, but also, under the conditions of coalbed methane well drainage with high coal powder content, certain viscosity of well fluid, and severe scaling, the flow field and direction of the well fluid located in the spiral groove are changed when the plunger reciprocates through it. This causes the well fluid in the spiral groove to flow, thereby flushing and cleaning the solid particles adhering to the spiral groove, preventing the accumulation of solid particles in the spiral groove, thus reducing the probability of pump jamming, extending the service life of the oil pump, reducing the frequency of well workover and pump inspection operations, and minimizing the impact on production.

Description

Technical Field

[0001] This utility model relates to the field of oil pump technology, and in particular to a self-cleaning anti-jamming oil pump. Background Technology

[0002] Coalbed methane extraction is carried out through drainage and pressure reduction. The downhole drainage equipment mainly uses reciprocating oil pumps, which are widely used in conventional oilfields during oil production, to pump water. This process is called coalbed methane well drainage.

[0003] During coalbed methane well drainage, the presence of large amounts of coal dust, sand, or soil particles in the drainage water often causes the plunger to become stuck in the pump barrel, resulting in well shutdown. This problem arises because, to allow for relative movement between the plunger and the pump barrel, they are typically assembled with a clearance fit. During operation, a pressure difference exists between the upper and lower ends of the plunger within the pump barrel, causing drainage water to flow into the gap between the pump barrel and the plunger. The coal dust, sand, or soil particles in the drainage water also enter this gap. Due to reduced flow velocity, small gap space, scaling, and other deposits, coal dust and sand particles accumulate and aggregate. When the resistance from these accumulated foreign objects exceeds the pump's lifting force, the plunger cannot continue upward, or it cannot descend due to obstruction, leading to pump jamming during drainage. This necessitates well repair and pump inspection, impacting production.

[0004] Currently, two common methods are used to solve this problem. One method is to install a sand-collecting groove on the plunger, so that when solid particles enter the gap between the plunger and the pump barrel, the sand-collecting groove can contain the solid particles, thus preventing solid particles from clogging the gap between the plunger and the pump barrel. However, since the sand-collecting groove is located on the plunger, it moves with the plunger, making it impossible for solid particles accumulated in the groove to be discharged. As the usage time increases, when the sand-collecting groove is full of accumulated solid particles, the pump jamming problem will still occur. The other method is to create an annular sand-collecting groove on the inner wall of the pump barrel. In this case, when solid particles enter the gap between the plunger and the pump barrel... When there is a gap, a sand-collecting trough can be used to hold solid particles, thereby preventing solid particles from clogging the gap between the plunger and the pump barrel. Since the annular sand-collecting trough is opened on the pump barrel, whenever the annular sand-collecting trough is exposed, the solid particles in the sand-collecting trough can be cleaned by the water flow. However, when encountering well fluid with a certain viscosity, such as in mines with a coal powder content greater than 3%, solid particles will stick to the annular sand-collecting trough, making it impossible to clean the solid particles stuck in the sand-collecting trough without external force. As the usage time increases, when the solid particles accumulated in the sand-collecting trough fill the sand-collecting trough, pump jamming problems will still occur. Utility Model Content

[0005] The purpose of this invention is to provide a self-cleaning anti-sticking oil pump, which reduces the probability of pump sticking, extends the service life of the oil pump, reduces the frequency of well repair and pump inspection operations, and minimizes the impact on production.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] This utility model provides a self-cleaning anti-jamming oil pump, which includes a pump barrel and a plunger. The plunger is axially reciprocatingly disposed inside the pump barrel, and the plunger and the pump barrel are clearance-fitted. A helical groove is formed on the inner wall of the pump barrel, and the helical groove is located within the stroke range of the plunger's reciprocating motion. The length of the plunger along the axial direction is L1, and the length of the helical groove along the axial direction is L, and L1 > L.

[0008] Optionally, the length L of the spiral groove along the axial direction and the length L1 of the plunger along the axial direction satisfy 0.04L1≤L≤0.1L1.

[0009] Optionally, the gap between the plunger and the pump barrel is T, and the depth of the spiral groove is H, satisfying 7.25T≤H≤20T.

[0010] Optionally, the clearance dimension T between the plunger and the pump barrel satisfies 0.05mm≤T≤0.138mm.

[0011] Optionally, the groove width of the spiral groove is W, and satisfies 2mm≤W≤3mm.

[0012] Optionally, the pitch of the spiral groove is P, and satisfies 50mm≤P≤100mm.

[0013] Optionally, the spiral groove has n turns, and satisfies 1≤n<L1 / P.

[0014] Optionally, the spiral groove includes an upper end and a lower end located on both sides of the axial direction, and the upper end is provided with an annular groove;

[0015] And / or, the lower end is provided with the annular groove.

[0016] Optionally, the cross-sectional shape of the spiral groove is triangular or trapezoidal.

[0017] Optionally, the spiral groove is a single-thread structure or a double-thread cross structure.

[0018] The beneficial effects of this utility model are:

[0019] This invention provides a self-cleaning anti-sticking oil pump, which includes a pump barrel and a plunger. A spiral groove with an axial length less than that of the plunger is formed on the inner wall of the pump barrel, and the spiral groove is positioned within the stroke range of the plunger's reciprocating motion. This allows the spiral groove to not only accommodate solid particles entering the gap between the plunger and the pump barrel, but also, in coalbed methane well drainage conditions with high coal powder content, certain viscosity of the well fluid, and severe scaling, to change the flow field and direction of the well fluid within the spiral groove as the plunger reciprocates. This causes the well fluid within the spiral groove to flow, flushing and cleaning the solid particles adhering to it, preventing their accumulation. Furthermore, the pressure change caused by the flow field alters the size of the solid particles, breaking and tearing them, thus reducing their volume. This reduces the probability of pump sticking, extends the pump's service life, reduces the frequency of well workover and pump inspection operations, and minimizes the impact on production. Attached Figure Description

[0020] Figure 1 This is a schematic diagram showing the position of the self-cleaning anti-jamming oil pump that does not reach the spiral groove during the upstroke.

[0021] Figure 2 This utility model provides a schematic diagram showing the position of the upper end of the plunger reaching the lower end of the spiral groove during the upstroke of a self-cleaning anti-jamming oil pump.

[0022] Figure 3 This utility model provides a schematic diagram showing the position of the plunger covering the entire spiral groove during the upstroke of a self-cleaning anti-jamming oil pump.

[0023] Figure 4 This is a schematic diagram showing the position of the lower end of the plunger away from the lower end of the spiral groove during the upstroke of the self-cleaning anti-jamming oil pump provided by this utility model.

[0024] In the picture:

[0025] 1. Pump cylinder;

[0026] 2. Plunger;

[0027] 3. Spiral groove;

[0028] 4. Solid particulate matter. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0030] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0033] Coalbed methane extraction is carried out through drainage and pressure reduction. The downhole drainage equipment mainly uses reciprocating oil pumps, which are widely used in conventional oilfields during oil production, to pump water. This process is called coalbed methane well drainage.

[0034] During coalbed methane well drainage, the presence of large amounts of coal dust, sand, or soil particles in the drainage water often causes the plunger to become stuck in the pump barrel, resulting in well shutdown. This problem arises because, to allow for relative movement between the plunger and the pump barrel, they are typically assembled with a clearance fit. During operation, a pressure difference exists between the upper and lower ends of the plunger within the pump barrel, causing drainage water to flow into the gap between the pump barrel and the plunger. The coal dust, sand, or soil particles in the drainage water also enter this gap. Due to reduced flow velocity, small gap space, scaling, and other deposits, coal dust and sand particles accumulate and aggregate. When the resistance from these accumulated foreign objects exceeds the pump's lifting force, the plunger cannot continue upward, or it cannot descend due to obstruction, leading to pump jamming during drainage. This necessitates well repair and pump inspection, impacting production.

[0035] Currently, two common methods are used to solve this problem. One method is to install a sand-collecting groove on the plunger, so that when solid particles enter the gap between the plunger and the pump barrel, the sand-collecting groove can contain the solid particles, thus preventing solid particles from clogging the gap between the plunger and the pump barrel. However, since the sand-collecting groove is located on the plunger, it moves with the plunger, making it impossible for solid particles accumulated in the groove to be discharged. As the usage time increases, when the sand-collecting groove is full of accumulated solid particles, the pump jamming problem will still occur. The other method is to create an annular sand-collecting groove on the inner wall of the pump barrel. In this case, when solid particles enter the gap between the plunger and the pump barrel... When there is a gap, a sand-collecting trough can be used to hold solid particles, thereby preventing solid particles from clogging the gap between the plunger and the pump barrel. Since the annular sand-collecting trough is opened on the pump barrel, whenever the annular sand-collecting trough is exposed, the solid particles in the sand-collecting trough can be cleaned by the water flow. However, when encountering well fluid with a certain viscosity, such as in mines with a coal powder content greater than 3%, solid particles will stick to the annular sand-collecting trough, making it impossible to clean the solid particles stuck in the sand-collecting trough without external force. As the usage time increases, when the solid particles accumulated in the sand-collecting trough fill the sand-collecting trough, pump jamming problems will still occur.

[0036] Therefore, in order to reduce the probability of pump jamming, extend the service life of the oil pump, reduce the frequency of well workover and pump inspection operations, and minimize the impact on production, this embodiment provides a self-cleaning anti-jamming oil pump.

[0037] like Figures 1 to 4As shown, the self-cleaning anti-jamming oil pump includes a pump barrel 1 and a plunger 2. The plunger 2 is axially reciprocatingly disposed inside the pump barrel 1. The plunger 2 and the pump barrel 1 are clearance-fitted. A spiral groove 3 is provided on the inner wall of the pump barrel 1. The spiral groove 3 is located within the stroke range of the plunger 2's reciprocating motion. The axial length of the plunger 2 is L1, and the axial length of the spiral groove 3 is L, satisfying L1 > L.

[0038] This self-cleaning anti-jamming oil pump includes a pump barrel 1 and a plunger 2. A spiral groove 3, with an axial length less than that of the plunger 2, is formed on the inner wall of the pump barrel 1. This spiral groove 3 is positioned within the stroke range of the plunger 2's reciprocating motion. This allows the spiral groove 3 to accommodate solid particles 4 that enter the gap between the plunger 2 and the pump barrel 1. Furthermore, in coalbed methane well drainage conditions with high coal powder content, high well fluid viscosity, and severe scaling, the spiral groove 3 alters the flow field and direction of the well fluid within it. This causes the well fluid within the spiral groove 3 to flow, flushing and cleaning the solid particles 4 adhering to it, preventing their accumulation. Simultaneously, the pressure change caused by the flow field alters the size of the solid particles 4, breaking and tearing them, thus reducing their volume. This reduces the probability of pump jamming, extends the pump's service life, decreases the frequency of well repair and pump maintenance, and minimizes the impact on production.

[0039] The structure of the spiral groove 3 can be freely configured according to requirements, such as a single-thread structure or a double-thread cross structure. In this embodiment, the spiral groove 3 is a single-thread structure.

[0040] In this embodiment, when the self-cleaning anti-sticking oil pump is used for operation, during the upstroke motion, as the plunger 2 moves upward, a small amount of well fluid will enter the gap between the pump barrel 1 and the plunger 2 due to the pressure difference between the two ends of the plunger 2 along its axial direction. This becomes the leakage flow rate, which is the amount of liquid leakage caused by the gaps between the moving parts inside the pump during operation. This leakage will reduce the actual output flow rate of the pump, affecting the efficiency and performance of the pump. The actual output flow rate is the theoretical input flow rate minus the leakage flow rate. The leakage flow rate will seal the gap between the pump barrel 1 and the plunger 2. Some solid particles 4 will enter the gap between the plunger 2 and the pump barrel 1 along with the well fluid as the leakage flow rate. A small amount of large solid particles 4 will remain in the gap due to the space limitation of the gap and will move upward with the plunger 2.

[0041] Because there is a pressure difference between the two ends of the plunger 2 along the axis, the well fluid, which is the discharge flow rate, will form a pressure difference gradient distribution along the axis of the plunger 2 when flowing in the gap. Under ideal conditions, the pressure difference gradient, the length of the plunger 2 and the pump head are linearly related. That is, for a specific pump and well, the pressure at the upper end of the plunger 2 drops uniformly along the axis to the pressure at the lower end. The pressure drop formed by the gap between the plunger 2 and the pump barrel 1 with the same spacing is equal. The flow field of the well fluid (along with the solid particles 4 carried by it), which is the flow field, refers to the motion state of the fluid in space. It is also uniformly distributed in the gap.

[0042] like Figure 2 As shown, during the upward movement of the plunger 2, when the upper end of the plunger 2 enters the cross section where the spiral groove 3 is located, the lower end of the spiral groove 3 is located in the cylindrical surface of the gap formed between the plunger 2 and the pump barrel 1. At this time, the pressure gradient that was previously stable due to the discharge flow will change. Compared to the gap, the spiral groove 3 with a certain depth and width has less resistance to the fluid, so the pressure difference between the two ends of the spiral groove 3 can be ignored. The upper end of the spiral groove 3 is exposed to the well fluid above the plunger 2. The hydraulic pressure at the upper end of the plunger 2 will be directly transmitted to the gap through the spiral groove 3. The pressure in the spiral groove 3 is greater than the pressure of the well fluid in the gap it contacts. A small amount of well fluid will enter the gap between the pump barrel 1 and the plunger 2 through the spiral groove 3, causing a sudden change in the pressure gradient in the very small local gap between the plunger 2 and the pump barrel 1. This significantly changes the flow field of the well fluid that was originally used as the discharge flow rate. The flow direction of the well fluid in the gap also undergoes a local sudden change, causing some of the solid particles 4 attached to the surface of the plunger 2 to move, break and tear under the action of the well fluid, thereby reducing the volume of the solid particles 4.

[0043] like Figure 3 As shown, as the plunger 2 continues to move upward, when the spiral groove 3 completely enters the cylindrical surface formed by the gap between the plunger 2 and the pump barrel 1, because the space formed by the spiral groove 3 is much larger than the gap space, a certain pressure gradient change is formed in the cylindrical surface formed by the gap, causing the solid particles 4 in the gap to move, causing the impurities distributed along the axial direction to change their direction of movement. When the larger solid particles 4 pass through the cross section of the spiral groove 3, they will enter the interior of the spiral groove 3 and no longer move upward with the plunger 2.

[0044] like Figure 4As shown, when the plunger 2 continues to move upward, exposing the lower end of the spiral groove 3 to the well fluid below the plunger 2, the pressure in the spiral groove 3 is less than the pressure in the gap. At this point, a sudden change in the local pressure gradient occurs in the spiral groove 3, and the flow direction of the well fluid, which serves as the discharge flow rate in the gap, also changes. Some of the solid particles 4 adhering to the surface of the plunger 2 move, break, and tear under the action of the well fluid. A small amount of well fluid, which serves as the discharge flow rate, flows from the gap into the spiral groove 3 and flows out through the spiral groove 3 into the pump barrel 1 below the plunger 2. At the same time, it flushes away the solid particles 4 adhering to the spiral groove 3, realizing automatic cleaning of the spiral groove 3 and preventing impurities from accumulating in the internal space of the spiral groove 3 for a long time, which could lead to pump jamming.

[0045] The principle of automatic cleaning when the plunger 2 is in the downstroke is the same as that when the plunger 2 is in the upstroke. Both utilize the large pressure gradient between the pump barrel 1 and the plunger 2 to provide the power for the spiral groove 3 to change the flow direction of the well fluid as the discharge flow rate and to clean the spiral groove 3. The process is just reversed in the upstroke.

[0046] Therefore, the self-cleaning anti-sticking oil pump provided in this embodiment can still automatically flush the spiral groove 3 even when the coal powder concentration is very high, the scaling is severe, and the well fluid has a certain viscosity, thus avoiding the long-term accumulation of solid particles 4 and the occurrence of pump sticking failure.

[0047] Furthermore, in actual use of oil pumps, the proportion of discharge flow is relatively small. Therefore, even in coalbed methane wells or oil wells with high coal powder concentration, considerable viscosity of well fluid, and severe scaling, the content of solid particles 4 carried in a single stroke is very small. Thus, the self-cleaning anti-jamming oil pump provided in this embodiment can achieve a flushing process during each stroke, automatically and forcibly cleaning the gap between the plunger 2 and the pump barrel 1, thereby greatly avoiding the occurrence of pump jamming problems.

[0048] Optionally, the axial length L of the spiral groove 3 and the axial length L1 of the plunger 2 satisfy 0.04L1≤L≤0.1L1. By limiting the axial length L of the spiral groove 3 and the axial length L1 of the plunger 2 to satisfy 0.04L1≤L≤0.1L1, it avoids both the length of the spiral groove 3 exceeding the length of the plunger 2 and the length of the spiral groove 3 being too short, resulting in limited space for accommodating solid particles 4. For example, when the length L1 of the plunger 2 is 1200mm, the axial length L of the spiral groove 3 is in the range of 48mm≤L≤120mm.

[0049] Optionally, the clearance dimension between the plunger 2 and the pump barrel 1 is T, and the depth dimension of the spiral groove 3 is H, satisfying 7.25T≤H≤20T. By limiting the clearance dimension T between the plunger 2 and the pump barrel 1 and the depth dimension H of the spiral groove 3, both satisfying 7.25T≤H≤20T, it avoids the spiral groove 3 being too shallow, which would prevent large solid particles 4 from being contained within the spiral groove 3, and also avoids the spiral groove 3 being too deep, which would result in insufficient remaining wall thickness of the pump barrel 1 and reduce the structural strength of the pump body.

[0050] Optionally, the clearance T between the plunger 2 and the pump barrel 1 satisfies 0.05mm≤T≤0.138mm. By limiting the clearance T between the plunger 2 and the pump barrel 1 to satisfy 0.05mm≤T≤0.138mm, it avoids two problems: firstly, the clearance between the pump barrel 1 and the plunger 2 is too small, which would cause the plunger 2 to jam and move poorly during reciprocating motion; secondly, it avoids the clearance between the pump barrel 1 and the plunger 2 being too large, which would allow a large amount of solid particles 4 to enter.

[0051] The gap dimension T between the plunger 2 and the pump barrel 1 can be any value between 0.05mm and 0.138mm or any two values, such as 0.05mm, 0.072mm, 0.094mm, 0.116mm, 0.138mm, etc.

[0052] Optionally, the width of the spiral groove 3 is W, and satisfies 2mm≤W≤3mm. By limiting the width W of the spiral groove 3 to satisfy 2mm≤W≤3mm, the width of the spiral groove 3 is prevented from being too small, which would prevent some larger solid particles 4 from entering the spiral groove 3.

[0053] Optionally, the pitch of the spiral groove 3 is P, and satisfies 50mm≤P≤100mm. By limiting the pitch P of the spiral groove 3 to satisfy 50mm≤P≤100mm, it avoids the situation where the pitch is too small, resulting in too small a wall thickness between the turns of the spiral groove 3 and weak structural strength.

[0054] The pitch P of the spiral groove 3 can be any value between 50mm and 100mm or any range between two values, such as 50mm, 60mm, 70mm, 80mm, 90mm, and 100mm.

[0055] Specifically, the spiral groove 3 has n turns, and satisfies 1≤n<L1 / P. By limiting the number of turns n of the spiral groove 3 to satisfy 1≤n<L1 / P, we can avoid having too few turns, which would reduce the total amount of solid particles 4 that the spiral groove 3 can hold. On the other hand, we can also avoid having too many turns when the pitch is constant, which would cause the length of the spiral groove 3 to exceed the length of the plunger 2.

[0056] Optionally, the spiral groove 3 includes an upper end and a lower end located on both sides of the axial direction, with an annular groove at the upper end. By providing an annular groove at the upper end of the spiral groove 3, the total amount of solid particles 4 that can be contained is increased.

[0057] Optionally, the spiral groove 3 includes an upper end and a lower end located on both sides of the axial direction, with a circular groove at the lower end. By providing a circular groove at the lower end of the spiral groove 3, the total amount of solid particles 4 that can be contained is increased.

[0058] Optionally, the cross-sectional shape of the spiral groove 3 is triangular or trapezoidal. By making the cross-sectional shape of the spiral groove 3 triangular or trapezoidal, the lower side of the spiral groove 3 is inclined downward, which is beneficial for the well fluid to clean solid particles.

[0059] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A self-cleaning, anti-jamming oil pump, characterized in that, The self-cleaning anti-jamming oil pump includes a pump barrel (1) and a plunger (2). The plunger (2) is axially movable within the pump barrel (1). The plunger (2) is clearance-fitted with the pump barrel (1). A spiral groove (3) is provided on the inner wall of the pump barrel (1). The spiral groove (3) is located within the stroke range of the plunger (2) during reciprocating motion. The length of the plunger (2) along the axial direction is L1, and the length of the spiral groove (3) along the axial direction is L, satisfying L1 > L.

2. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The length L of the spiral groove (3) along the axial direction and the length L1 of the plunger (2) along the axial direction satisfy 0.04L1≤L≤0.1L1.

3. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The gap between the plunger (2) and the pump barrel (1) is T, and the depth of the spiral groove (3) is H, satisfying 7.25T≤H≤20T.

4. The self-cleaning anti-jamming oil pump according to claim 3, characterized in that, The gap dimension T between the plunger (2) and the pump barrel (1) satisfies 0.05mm≤T≤0.138mm.

5. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The groove width of the spiral groove (3) is W, and satisfies 2mm≤W≤3mm.

6. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The pitch of the spiral groove (3) is P, and satisfies 50mm≤P≤100mm.

7. The self-cleaning anti-jamming oil pump according to claim 6, characterized in that, The spiral groove (3) has n turns, and satisfies 1≤n<L1 / P.

8. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The spiral groove (3) includes an upper end and a lower end located on both sides of the axial direction, and the upper end is provided with an annular groove; And / or, the lower end is provided with the annular groove.

9. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The cross-sectional shape of the spiral groove (3) is triangular or trapezoidal.

10. The self-cleaning anti-jamming oil pump according to claim 1, characterized in that, The spiral groove (3) is a single thread structure or a double thread cross structure.

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