A sand sticking prevention device for oil well pump body

Abstract

The application provides a sand sticking prevention device for an oil well pump body, which comprises a body with an inner cavity, a pipe body arranged in the inner cavity, and a first channel for transporting matter between the pipe body and the body. A sand blocking piece is arranged on the outer wall of the pipe body, which can keep the first channel unblocked when the oil well is running and automatically block the first channel when the oil well is stopped. The sand sticking prevention device for the oil well pump body can prevent the downhole pump body from being blocked by the deposition of formation sand when the oil well is stopped, effectively prevent sand sticking accidents of the downhole pump body for a long time, and reduce the maintenance frequency of the oil well.

Description

Technical Field

[0001] This invention relates to the field of oilfield development, and more specifically to a sand-proof device for an oil well pump body. Background Technology

[0002] In oil extraction, oilfield well production primarily utilizes pumps such as screw pumps to extract oil from the wellhead. However, the formation generates a large amount of gravel during oil extraction, which can easily clog screw pumps, causing wear and sand blockage. Especially when a well is shut down and downhole fluid circulation ceases, the screw pump, often located at the bottom of the well, will accumulate gravel under gravity, making it more prone to sand blockage and severely impacting normal oil production operations.

[0003] Currently, one commonly used sand control technology involves installing a sand anchor below the screw pump. This separates sand carried in the crude oil from the oil and stores it in the downhole tubing below the pump body, thus removing formation sand before it enters the pump. However, this method is prone to saturation with sand and gravel in the downhole tubing, making it difficult to maintain its effectiveness for extended periods. Furthermore, this method is also susceptible to clogging of the screw pump by formation sand deposits above it after the well is shut down.

[0004] Another commonly used sand-blocking technology involves adding a sand-blocking device to the pump. However, this sand-blocking effect is not ideal, and sand jamming accidents can easily occur when sand discharge is severe. Furthermore, when too much sand settles above the sand-blocking device, the sand jam may become impossible to release. Therefore, this method is unlikely to provide long-term sand-blocking protection. Summary of the Invention

[0005] To address the technical problems described above, this invention aims to provide a sand-blocking device for oil well pump bodies. This sand-blocking device for oil well pump bodies can prevent formation sand from depositing and clogging the downhole pump body when the oil well is shut down, and can effectively prevent sand blockage accidents in the downhole pump body for a long period, reducing the maintenance frequency of the oil well.

[0006] According to the present invention, a sand-blocking device for an oil well pump body is provided, comprising: a body having an inner cavity, wherein a pipe is disposed within the inner cavity, and a first channel for material transport is provided between the pipe and the body.

[0007] A sand-blocking component is provided on the outer wall of the pipe body. The sand-blocking component can keep the first channel unobstructed when the oil well is running and automatically block the first channel when the oil well is shut down.

[0008] In a preferred embodiment, the sand separator is configured as a spiral blade that can rotate synchronously with the tube body, with the end of the spiral blade away from the tube body connected to the inner wall of the body.

[0009] In a preferred embodiment, at least one sand-breaking rod is further provided on the outer wall of the tube body, the sand-breaking rod being located upstream of the sand-separating member. The sand-breaking rod extends radially along the body, forming a second channel for material transport that communicates with the first channel between the sand-breaking rod and the radial direction of the body.

[0010] In a preferred embodiment, the free end of the sand-breaking rod away from the tube is constructed in a conical shape.

[0011] In a preferred embodiment, a plurality of sand-breaking rods are provided, which are uniformly arranged along the axial and / or circumferential direction of the pipe body, or the plurality of sand-breaking rods arranged circumferentially are staggered along the axial direction of the pipe body.

[0012] In a preferred embodiment, a straightening ring is provided at each end of the main body, the diameter of the straightening ring being slightly larger than the diameter of the tube body, and the two ends of the tube body extending out of the main body and passing through the straightening ring.

[0013] In a preferred embodiment, a friction ring is further fitted onto the straightening ring, the diameter of which is the same as the diameter of the body, forming a third channel for material transport between the straightening ring and the friction ring, which is connected to the second channel.

[0014] In a preferred embodiment, the friction ring and the straightening ring are connected by a plurality of connecting rods disposed on the inner wall of the friction ring.

[0015] In a preferred embodiment, a rotary bearing is further provided between the connecting rod and the straightening ring.

[0016] In a preferred embodiment, connecting threads are also provided on the outer walls at both ends of the tube. Attached Figure Description

[0017] The invention will now be described with reference to the accompanying drawings.

[0018] Figure 1 A schematic diagram of a sand-proof device for an oil well pump body according to an embodiment of the present invention is shown.

[0019] Figure 2 for Figure 1 The diagram shown is a cross-sectional view of the sand guard device for the oil well pump body along plane A-A'.

[0020] In this application, all drawings are schematic and are used only to illustrate the principles of the invention, and are not drawn to scale. Detailed Implementation

[0021] The invention will now be described with reference to the accompanying drawings. In the following text, the terms "upper end" and "upper side" refer to the end and side facing the wellhead, respectively; the terms "lower end" and "lower side" refer to the end and side away from the wellhead, respectively.

[0022] Figure 1 A sand-blocking device 100 for an oil well pump body according to an embodiment of the present invention is shown. Figure 1 As shown, the sand-blocking device 100 for oil well pump bodies includes a body 10, which may be configured as a tube or cylinder, and defines an inner cavity 20 within the body 10.

[0023] like Figure 1 As shown, a tube body 30 is provided inside the inner cavity 20. The upper end 32 and the lower end 34 of the tube body 30 extend out of the inner cavity 20, respectively. Furthermore, connecting threads 341 are respectively provided on the outer walls of the upper end 32 and the lower end 34 of the tube body 30, so that the upper end 32 and the lower end 34 of the tube body 30 are connected to the downhole pump body (not shown) and the sucker rod (not shown) respectively through the connecting threads 341, so that the body 10 is located between the downhole pump body and the sucker rod.

[0024] A gap 25 is formed radially between the pipe body 30 and the main body 10, forming a first channel 28 for downhole material transportation. Simultaneously, a sand-blocking element 35 is provided on the outer wall of the pipe body 30 near its lower end 34. The sand-blocking element 35 is in contact with the inner wall of the main body 10, allowing it to close the first channel 28 and thus block the transportation of downhole material on both sides of the sand-blocking element 35.

[0025] In this invention, the sand-blocking component 35 is constructed as a spiral blade 351 disposed on the outer wall of the pipe body 30. The spiral blade 351 can rotate synchronously with the rotation of the pipe body 10. Thus, when the pipe body 10 is stationary, the spiral blade 351 is in contact with the inner wall of the pipe body 10, thereby blocking the first channel 28; when the pipe body 10 rotates under the action of external force, it can drive the spiral blade 351 to rotate. It is easy to understand that when the spiral blade 351 starts to rotate, it can play a material transport role, thereby allowing the downhole material located on the lower side of the spiral blade 351 to reach the upper side of the spiral blade 351 through the spiral blade 351, thereby ensuring the unobstructed flow of the first channel 28.

[0026] In summary, when the oil well is in normal operation, the tubing 30 rotates along with the sucker rod downhole, causing the spiral blades 351 to rotate as well. When the spiral blades 351 rotate, they transport formation sand and other downhole impurities from below the blades, moving these impurities to the upper side of the blades and then, with the help of the downhole fluid, to the wellhead. This prevents impurities from depositing at the downhole pump and affecting its normal operation.

[0027] When the oil well stops operating for any reason, formation sand and other impurities will settle and descend under gravity, falling into the inner cavity 20 on the upper side of the spiral blade 351. Since the sucker rod stops rotating at this time, the tubing 30 and the spiral blade 351 will also stop rotating. The spiral blade 351 can close the first channel 28, causing formation sand and other impurities in the inner cavity 20 to deposit on the upper side of the spiral blade 351, thereby preventing formation sand and other impurities from clogging the downhole pump.

[0028] In addition, when an oil well stops operating for any reason, due to deposition, formation gravel will form dense sand blocks in the inner cavity 20 on the upper side of the spiral blade 351. These dense sand blocks will hinder the normal circulation of downhole fluids when the oil well restarts, and at the same time block the first channel 28, affecting normal drilling operations.

[0029] Therefore, as Figure 1 As shown, at least one sand-breaking rod 36 is also provided on the outer wall of the pipe body 30 above the spiral blade 351. The sand-breaking rod 36 extends radially along the body 10 and can rotate synchronously with the pipe body 30. Thus, when the oil well restarts operation, the sand-breaking rod 36 can cut the sand blocks formed by the formation gravel deposits by rotation, and break the sand blocks into smaller sand particles. This allows the downhole fluid to carry these smaller sand particles and ultimately transport them to the wellhead.

[0030] Meanwhile, the sand-breaking rod 36 is not in contact with the inner wall of the body 10, thus forming a second channel 38 for material transport in the radial direction between the sand-breaking rod 36 and the body 10, which communicates with the first channel 28. It is easy to understand that this arrangement facilitates the passage of downhole fluids carrying formation gravel through the sand-breaking rod 36.

[0031] In a preferred embodiment, the plurality of sand-breaking rods 36 are uniformly arranged in the axial or circumferential direction of the pipe body 30, thereby increasing the density of the sand-breaking rods 36 and breaking the deposited sand blocks into smaller sand particles, which facilitates the transportation of downhole fluids.

[0032] In this invention, the multiple sand-breaking rods 36 can be arranged simultaneously along the axial and circumferential directions of the tube body 30. Furthermore, the multiple sand-breaking rods 36 arranged circumferentially are staggered along the axial direction of the tube body 30, thereby further increasing the arrangement density of the sand-breaking rods 36 and reducing the volume of the cut sand particles.

[0033] Meanwhile, the free end 361 of the sand-breaking rod 36, away from the tube body 30, is preferably constructed in a conical shape. This configuration can improve the sand-breaking rod 36's ability to cut sand blocks.

[0034] In one embodiment not shown, the sand-breaking rod 36 can be replaced by a propeller (not shown) fitted onto the tube. When the propeller rotates with the tube, it not only cuts sand blocks but also provides a lift force towards the wellhead for the downhole fluid flowing through the second conduit 38, thus facilitating downhole fluid circulation. Such propellers are well known to those skilled in the art, and a detailed description thereof is omitted here.

[0035] like Figure 1 As shown, a centralizing ring 40 is provided at each of the axial ends of the main body 10. Both ends of the pipe body 30 extend beyond the exterior of the main body 10 and pass through the centralizing ring 40. The diameter of the centralizing ring 40 is slightly larger than the diameter of the pipe body 30, allowing the pipe body 30 to form a clearance fit with the centralizing ring 40 when passing through it. Simultaneously, the centralizing ring 40 is fixedly installed on the main body 10. Therefore, when the pipe body 30 passes through the centralizing ring 40, the centralizing ring 40 can fix the pipe body 30, preventing it from rubbing against the inner wall of the oil well due to shaking, thus affecting the insertion of the pipe body 30 into the well or normal oil production operations.

[0036] Since the diameter of the pipe body 30 is much smaller than the diameter of the main body 10, the diameter of the centralizing ring 40 will also be smaller than the diameter of the main body 10, thus forming a step 45 between the centralizing ring 40 and the main body 10. To prevent the step 45 from getting stuck on the well wall during the insertion or extraction of the main body 10, a friction ring 50 is also fitted onto the centralizing ring 40. The friction ring 50 has the same diameter as the main body 10, thereby covering the step 45 and preventing the step 45 from affecting normal insertion or extraction operations.

[0037] In a preferred embodiment, the friction ring 50 is made of a rubber material with a high coefficient of friction. This material has a certain elastic deformation, which can adapt to changes in the dimensions of the well wall to a certain extent. On the other hand, its high coefficient of friction can also prevent relative rotation between the friction ring 50 and the well wall, thus preventing disruption to normal oil production operations.

[0038] Figure 2 for Figure 1 The diagram shown is a cross-sectional view of the sand-blocking device 100 for the oil well pump body along plane A-A'. Figure 2 As shown, the friction ring 50 and the straightening ring 40 are connected by a plurality of connecting rods 55 disposed on the inner wall of the friction ring 50. The plurality of connecting rods 55 are evenly arranged along the circumference of the friction ring 50.

[0039] Meanwhile, a gap 56 is provided between any two adjacent connecting rods 55, forming a third channel 58 for material transport that communicates with the second channel 38. Thus, when downhole fluid reaches the friction ring 50 along the second channel 38, it can flow out through the third channel 58, thereby preventing the friction ring 50 from obstructing the circulation of downhole fluid.

[0040] In a preferred embodiment, a rotary bearing 60 is further provided between the connecting rod 55 and the tube body 30. The rotary bearing 60 can form a sliding friction pair, thereby reducing the friction between the connecting rod 55 and the tube body 30 when the tube body 30 and the connecting rod 55 rotate relative to each other. Such a rotary bearing 60 is well known to those skilled in the art, and its detailed description is omitted here.

[0041] The working process of the sand-proof clamping device 100 for oil well pump body according to the present invention is briefly described below.

[0042] The sand-blocking device 100 for oil well pump bodies of the present invention is installed on the upper side of the downhole pump body and is lowered into the oil well together with the downhole pump body. When the oil well is in normal production, the spiral blades 351 and the pipe body 30 rotate synchronously. At this time, the first channel 28 is in a connected state, and the formation sand on the lower side of the body 10 can be normally transported to the wellhead through the first channel 28, the second channel 38 and the third channel 58 in sequence under the drive of the downhole fluid.

[0043] When the well is shut down due to an internal malfunction, the formation sand carried in the downhole fluid will settle and descend under gravity, falling into the main body 10. At this time, since the pipe body 30 stops rotating, the spiral blades 351 will also stop rotating. As a result, the first channel 28 will be in a closed state, and the spiral blades 351 can prevent the formation sand from settling further into the downhole pump body, thereby preventing sand jamming accidents.

[0044] When the well is reopened, the tubing 30 will rotate again under the influence of the sucker rod, causing the spiral blades 351 to rotate again, thus reconnecting the first channel 28. Simultaneously, the sand-breaking rod 36 will also rotate under the influence of the tubing 30, cutting the sand column deposited by the spiral blades 351 into smaller sand particles. These smaller sand particles will then move towards the wellhead under the influence of the downhole fluid.

[0045] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A sand-blocking device (100) for an oil well pump body, the sand-blocking device being installed on the upper side of the downhole pump body, comprising: The body (10) has an inner cavity (20), in which a tube (30) is provided, and a first channel (28) for material transport is provided between the tube and the body. A sand-blocking component (35) is provided on the outer wall of the pipe body. This sand-blocking component can keep the first channel unobstructed during well operation and automatically block the first channel when the well is shut down. The sand-blocking component is constructed as a spiral blade (351) that can rotate synchronously with the pipe body; and At least one sand-breaking rod (36) is provided on the outer wall of the tube body. The sand-breaking rod is provided on the upper side of the spiral blade. The sand-breaking rod extends radially along the body body. A second channel (38) for material transport is formed between the sand-breaking rod and the body body and is connected to the first channel. The free end (361) of the sand-breaking rod away from the tube body is constructed in a conical shape. When the well is shut down, the spiral blades are designed to prevent formation sand from sinking into the downhole pump body. During well operation, the spiral blades are configured to move downhole fluid from the first channel to the second channel, and the sand-breaking rods are configured to cut the sand columns deposited on the spiral blades into smaller sand particles.

2. The sand-blocking device (100) for an oil well pump body according to claim 1, characterized in that, The end of the spiral blade furthest from the tube body is connected to the inner wall of the main body.

3. The sand-blocking device (100) for an oil well pump body according to claim 1 or 2, characterized in that, Multiple sand-breaking rods are provided, and the multiple sand-breaking rods are evenly arranged along the axial and / or circumferential direction of the pipe body, or Multiple sand-breaking rods arranged circumferentially are staggered along the axial direction of the pipe body.

4. The sand-blocking device (100) for an oil well pump body according to claim 1 or 2, characterized in that, A straightening ring (40) is provided at each end of the main body, and the diameter of the straightening ring is set to be slightly larger than the diameter of the tube body. Both ends of the tube extend out of the body and pass through the straightening ring.

5. The sand-blocking device (100) for an oil well pump body according to claim 4, characterized in that, A friction ring (50) is also fitted onto the straightening ring, and the diameter of the friction ring is set to be the same as the diameter of the body. A third channel (58) for material transport is formed between the straightening ring and the friction ring and is connected to the second channel.

6. The sand-blocking device (100) for an oil well pump body according to claim 5, characterized in that, The friction ring and the straightening ring are connected by a plurality of connecting rods (55) provided on the inner wall of the friction ring.

7. The sand-proof clamping device for an oil well pump body according to claim 6, characterized in that, A rotary bearing (60) is also provided between the connecting rod and the straightening ring.

8. The sand-blocking device for an oil well pump body according to claim 1 or 2, characterized in that, Connecting threads (341) are also provided on the outer walls at both ends of the tube.

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