Sand control oil production water injection wellhead device

Abstract

This invention provides a sand-control oil production water injection wellhead device, relating to the field of oil production water injection technology. It includes a wellhead body, with a sand-control barrel connected to the upper end of the wellhead body, and a water injection pipe connected to the upper end of the sand-control barrel. A sand-control disc is installed inside the sand-control barrel, supported at the bottom by several support components. A first rotating shaft is fixedly installed at the center of the sand-control disc. A driving mechanism is installed on the water injection pipe to drive the first rotating shaft to rotate. Sand-control holes are symmetrically arranged on the left and right sides of the sand-control disc, and sand-control mesh is installed inside each sand-control hole. The central axis of one sand-control hole is collinear with the central axis of the water injection pipe and the central axis of the wellhead body. A cleaning hole is located directly above the other sand-control hole, with a sealing cover plate outside the cleaning hole and a sealing component located directly below it. In this invention, when one sand-control mesh intercepts sand particles, the other sand-control mesh can be cleaned through the cleaning hole, achieving maintenance without shutting down the well and eliminating well downtime caused by cleaning the sand-control mesh, thus ensuring the continuity of water injection operations.

Description

Technical Field

[0001] This invention relates to the field of oil production and water injection technology, and in particular to a sand-control oil production and water injection wellhead device. Background Technology

[0002] In oil extraction, water injection wells are crucial for maintaining reservoir pressure and enhancing oil recovery. However, during long-term water injection operations, sand particles carried in the water can easily enter the wellhead equipment, causing wear and blockage of internal components, affecting the normal operation of the wellhead equipment, and reducing the water injection efficiency and service life of the well.

[0003] To address the aforementioned sand particle hazard problem, existing oilfield water injection wellhead devices typically incorporate a filter structure within the wellhead flow channel to intercept sand particles and impurities in the water. For example, Chinese Patent CN115382264B discloses a wellhead filtration device for oilfield water injection wells. Its structure includes: an injection end, a filter, a flow chamber, a base, and a balance block. The injection end is embedded in the upper part of the filter, the lower part of the filter communicates with the flow chamber, the base is fixed to the outer edge of the flow chamber, and the balance block is welded to both sides of the base. This invention further improves upon the filter by using a connecting frame and pull valve on the side of the filter screen's limiting body. After a large amount of impurities accumulate on the filter screen surface, the filter screen can be directly pulled out from below the injection end by a pulling action. This facilitates timely replacement and cleaning of the filter screen, preventing blockages caused by the inability to replace it during use. Furthermore, the ball bearing effect of the limiting body surface auxiliary device replaces the original friction pulling effect, preventing damage to the surface precision caused by continuous friction and ultimately leading to unstable assembly.

[0004] However, when replacing or cleaning the above-mentioned filter screen, in order to prevent high-pressure water from overflowing from the filter screen installation port, it is necessary to stop the water injection operation, which would affect the continuity of the water injection operation. Summary of the Invention

[0005] This invention provides a sand-control oil production water injection wellhead device to solve the technical problem that the water injection operation needs to be stopped when the filter screen of the current oil production water injection wellhead device is replaced or cleaned, which affects the continuity of the water injection operation.

[0006] To solve the above-mentioned technical problems, the present invention discloses a sand-control oil production water injection wellhead device, comprising: a wellhead body, a sand-control barrel connected to the upper end of the wellhead body, a water injection pipe connected to the upper end of the sand-control barrel, a sand-control disc inside the sand-control barrel, the bottom of the sand-control disc being supported by several support components, a first rotating shaft fixedly mounted at the center of the sand-control disc, the upper end of the first rotating shaft extending to the outside of the sand-control disc and rotatably connected to a sliding plate, the sliding plate being slidably connected to the outer wall of the water injection pipe, a driving mechanism mounted on the water injection pipe for driving the first rotating shaft to rotate, sand-control holes symmetrically arranged on the left and right sides of the sand-control disc, sand-control meshes installed inside the sand-control holes, the central axis of one sand-control hole being collinear with the central axis of the water injection pipe and the central axis of the wellhead body, a cleaning hole being positioned directly above the other sand-control hole, the cleaning hole being positioned at the upper end of the sand-control barrel, a sealing cover being positioned outside the cleaning hole, and a sealing component being positioned directly below the cleaning hole for sealing the lower end of the sand-control hole.

[0007] Preferably, the diameter of the sand-proof bucket is larger than the diameter of the water injection pipe, and the thickness of the sand-proof mesh is smaller than the thickness of the sand-proof disc.

[0008] Preferably, a number of support components are arranged in a circular array about the central axis of the sandproof disc. Each support component includes a support sleeve, the lower end of which is connected to the bottom wall of the sandproof disc. A support spring is installed inside the support sleeve, and a support column is installed at the upper end of the support spring. The upper end of the support column extends to the bottom of the sandproof disc and is rotatably positioned with a positioning ball. The bottom wall of the sandproof disc is provided with positioning holes corresponding to the positioning ball.

[0009] Preferably, sealing components are symmetrically arranged on the left and right sides of the first rotating shaft. The sealing components include a first sealing plate, the upper end of which is connected to the inner wall of the upper end of the sandproof barrel, and the front and rear ends of the first sealing plate are respectively connected to the inner walls of the front and rear sides of the sandproof barrel. A sliding cavity is provided in the first sealing plate, and a compression spring is provided in the sliding cavity. One end of the compression spring is connected to the top wall of the sliding cavity, and the other end of the compression spring is connected to a second sealing plate. The second sealing plate is slidably connected to the inner wall of the sliding cavity. The length of the second sealing plate is equal to the length of the first sealing plate. A sealing groove corresponding to the second sealing plate is provided on the upper surface of the sandproof disc, and the lower end of the second sealing plate is located in the sealing groove.

[0010] Preferably, the drive mechanism includes a drive assembly and a transmission assembly. The drive assembly includes a fixed plate, which is horizontally disposed inside the water injection pipe. One end of the fixed plate is fixedly connected to the inner wall of the water injection pipe. A second rotating shaft is rotatably disposed inside the fixed plate. Several fan blades are disposed at the upper end of the second rotating shaft, and a first bevel gear is disposed at the lower end of the second rotating shaft. A third rotating shaft is rotatably disposed on the side wall of the water injection pipe. The third rotating shaft is perpendicular to the second rotating shaft. A second bevel gear is disposed at one end of the third rotating shaft, and the second bevel gear meshes with the first bevel gear. The other end of the third rotating shaft extends to the outside of the water injection pipe and is disposed thereon. The third bevel gear drives the first rotating shaft to rotate through the transmission assembly.

[0011] Preferably, the transmission assembly includes a mounting plate, on which a fourth rotating shaft is mounted. The central axis of the fourth rotating shaft is on the same vertical line as the central axis of the first rotating shaft. A fourth bevel gear is mounted at the upper end of the fourth rotating shaft, meshing with a third bevel gear. A crossbar is mounted at the lower end of the fourth rotating shaft, perpendicular to the fourth rotating shaft. A fixed shaft is mounted at the end of the crossbar furthest from the fourth rotating shaft. A first pawl is rotatably mounted on the fixed shaft. A torsion spring is mounted on the fixed shaft, with one end connected to the fixed shaft and the other end connected to the first pawl. A rotating ring is rotatably mounted near the upper end of the first rotating shaft, and a fixed device is mounted on the outside of the rotating ring. A first ratchet is provided, and a first pawl engages with the external teeth of the first ratchet. A spring is provided on the outside of the rotating ring, with one end of the spring connected to the outer wall of the rotating ring and the other end connected to the upper surface of the sliding plate. A second ratchet is fixedly provided on the upper end of the first rotating shaft, and the second ratchet is located inside the first ratchet. The teeth of the second ratchet are opposite in direction to those of the first ratchet. A second pawl is provided on the inner wall of the first ratchet, with one end of the second pawl hinged to the inner wall of the first ratchet and the other end engaging with the external teeth of the second ratchet. The second pawl is connected to the inner wall of the first ratchet near the middle position via a spring wire.

[0012] Preferably, the transmission assembly is covered with a dust cover.

[0013] Preferably, the sealing assembly includes a sealing seat, which is frustum-shaped and located directly below the sand-proof net. An electric push rod is installed on the bottom wall of the sand-proof bucket, and a drive plate is installed at the output end of the electric push rod. A drive rod is installed on the upper surface of the drive plate, and the upper end of the drive rod passes through the bottom wall of the sand-proof bucket and is connected to the sealing seat. The drive rod and the bottom wall of the sand-proof bucket are connected in a sealed sliding connection. A drain hole is provided on the upper part of the side wall of the sand-proof bucket away from the water injection pipe. The drain hole is connected to the space above the sand-proof disc. A sealing plate is installed outside the drain hole. The sealing plate is slidably connected to the side wall of the sand-proof bucket. The lower end of the sealing plate is connected to the drive plate through a connecting rod. A connecting hole is opened in the sealing plate, and the connecting hole is located diagonally below the drain hole.

[0014] Preferably, a baffle is provided below the sealing seat, and the center of the baffle is slidably connected to the outer wall of the drive rod. A connecting spring is provided between the baffle and the sealing seat, with one end of the connecting spring connected to the upper surface of the baffle and the other end of the connecting spring connected to the lower surface of the sealing seat.

[0015] Preferably, a sealing barrel is installed between the sandproof disc and the cleaning hole. The upper end of the sealing barrel is connected to the inner wall of the upper end of the sandproof barrel. The diameter of the inner wall of the sealing barrel is larger than the diameter of the cleaning hole, and the central axis of the sealing barrel and the central axis of the cleaning hole are on the same vertical line.

[0016] The technical solution of the present invention has the following advantages: The present invention provides a sand-prevention oil production water injection wellhead device, which relates to the field of oil production water injection technology. It includes a wellhead body, a sand-prevention barrel connected to the upper end of the wellhead body, a water injection pipe connected to the upper end of the sand-prevention barrel, a sand-prevention disc inside the sand-prevention barrel, the bottom of the sand-prevention disc being supported by several support components, a first rotating shaft fixedly installed at the center of the sand-prevention disc, the upper end of the first rotating shaft extending to the outside of the sand-prevention disc and rotatably connected to a sliding plate, the sliding plate being slidably connected to the outer wall of the water injection pipe, a driving mechanism installed on the water injection pipe, the driving mechanism being used to drive the first rotating shaft to rotate, sand-prevention holes symmetrically arranged on the left and right sides of the sand-prevention disc, a sand-prevention mesh installed inside the sand-prevention holes, the central axis of one sand-prevention hole being collinear with the central axis of the water injection pipe and the central axis of the wellhead body, a cleaning hole being provided directly above the other sand-prevention hole, the cleaning hole being located at the upper end of the sand-prevention barrel, a sealing cover being provided outside the cleaning hole, and a sealing component being provided directly below the cleaning hole, the sealing component being used to seal the lower end of the sand-prevention hole. In this invention, when one sand-proof net intercepts sand particles, another sand-proof net can be cleaned through the cleaning hole, thereby achieving non-stop maintenance, eliminating the downtime of the water injection well caused by cleaning the sand-proof net, and ensuring the continuity of water injection operations.

[0017] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the means particularly pointed out in the written description and the accompanying drawings.

[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the internal structure of a sand-control and water injection wellhead device for oil production according to the present invention; Figure 2 This is a schematic diagram of the overall structure of a sand-control and water injection wellhead device for oil production according to the present invention; Figure 3 For the present invention Figure 1 Enlarged view of the structure at point A in the middle; Figure 4 This is a top view of the transmission component structure in this invention; Figure 5 For the present invention Figure 1 Enlarged view of the structure at point B in the middle; Figure 6 For the present invention Figure 1 Enlarged view of the structure at point C; Figure 7This is a top view of the sand-proof disc in this invention; Figure 8 For the present invention Figure 1 Enlarged view of the structure at point D.

[0020] In the diagram: 1. Wellhead body; 2. Sand control chamber; 3. Water injection pipe; 4. Sand control disc; 5. First rotating shaft; 6. Sliding plate; 7. Sand control hole; 8. Sand control mesh; 9. Cleaning hole; 10. Sealing cover plate; 11. Support sleeve; 12. Support spring; 13. Support column; 14. Positioning ball; 15. First sealing plate; 16. Sliding cavity; 17. Compression spring; 18. Second sealing plate; 19. Sealing groove; 20. Fixing plate; 21. Second rotating shaft; 22. Fan blade; 23. First bevel gear; 24. Third rotating shaft; 25. Second bevel gear; 26. 27. Third bevel gear; 28. Mounting plate; 29. ​​Fourth rotating shaft; 30. Fourth bevel gear; 31. Crossbar; 32. Fixed shaft; 33. First pawl; 34. Torsion spring; 35. Rotating ring; 36. First ratchet; 37. Clockwork spring; 38. Second ratchet; 39. Spring wire; 40. Dust cover; 41. Sealing seat; 42. Electric push rod; 43. Drive plate; 44. Drive rod; 45. Drain hole; 46. Sealing plate; 47. Connecting rod; 48. Connecting hole; 49. Baffle; 50. Connecting spring; 51. Sealing barrel. Detailed Implementation

[0021] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0022] Furthermore, in this invention, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions and features of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0023] Example 1: This embodiment of the invention provides a sand control and water injection wellhead device for oil production, such as... Figures 1-8As shown, it includes: a wellhead body 1, a sand-proof barrel 2 connected to the upper end of the wellhead body 1, a water injection pipe 3 connected to the upper end of the sand-proof barrel 2, a sand-proof disc 4 inside the sand-proof barrel 2, the bottom of the sand-proof disc 4 being supported by several support components, a first rotating shaft 5 fixedly installed at the center of the sand-proof disc 4, the upper end of the first rotating shaft 5 extending to the outside of the sand-proof disc 4 and rotatably connected to a sliding plate 6, the sliding plate 6 slidingly connected to the outer wall of the water injection pipe 3, a driving mechanism installed on the water injection pipe 3, the driving mechanism being used to drive the first rotating shaft 5 to rotate, sand-proof holes 7 symmetrically arranged on the left and right sides of the sand-proof disc 4, a sand-proof mesh 8 installed inside the sand-proof holes 7, the central axis of one sand-proof hole 7 being on the same straight line as the central axis of the water injection pipe 3 and the central axis of the wellhead body 1, a cleaning hole 9 being installed directly above the other sand-proof hole 7, the cleaning hole 9 being located at the upper end of the sand-proof barrel 2, a sealing cover plate 10 being installed outside the cleaning hole 9, and a sealing component being installed directly below the cleaning hole 9, the sealing component being used to seal the lower end of the sand-proof hole 7.

[0024] The working principle and beneficial effects of the above technical solution are as follows: When water is injected into the wellhead device, the sand-prevention disc 4 inside the sand-prevention tank 2 is supported by several support components, and the sand-prevention disc 4 is in a horizontal state. At this time, the central axis of the sand-prevention hole 7 on the left side of the sand-prevention disc 4 is on the same vertical line as the central axis of the water injection pipe 3 and the wellhead body 1. The high-pressure water delivered by the water injection pipe 3 can flow into the sand-prevention tank 2, and then be filtered through the sand-prevention mesh 8 in the sand-prevention hole 7 on the left side to remove sand particles and impurities from the water. The filtered clean water flows into the water injection well formation along the wellhead body 1, realizing sand prevention and water injection operation. At the same time, the sand-prevention hole 7 on the right side is directly below the cleaning hole 9, and the cleaning hole 9 is cleaned. The sealing cover 10 is used to seal the sand hole 9. The sealing cover 10 can be detachably connected to the upper surface of the sandproof bucket 2 by bolts to ensure the airtightness of the sandproof bucket 2. When the left sandproof net 8 is intercepting sand particles, the staff can clean the right sandproof net 8. Specifically, the lower end of the right sandproof hole 7 is sealed by the sealing component below the right sandproof net 8 to prevent high-pressure water in the sandproof bucket 2 from leaking through the right sandproof hole 7, ensuring the airtightness and pressure stability of the water injection process. After the sealing component is sealed, the sealing cover 10 is opened to clean the right sandproof net 8. After cleaning, the sealing cover is reinstalled. Plate 10 is sufficient. When the sand filter 8 on the left side becomes clogged due to sand accumulation (clogging means that the water injection pressure on the water injection pipe 3 side and the pressure after filtration by the sand filter 8 form a pressure difference of more than 0.3MPa), the drive mechanism on the water injection pipe 3 can drive the first rotating shaft 5 to rotate. The first rotating shaft 5 drives the sand filter disc 4 to rotate 180° inside the sand filter barrel 2, so that the positions of the sand filter 8 on the left and right sides are exchanged. The sand filter 8 that was originally on the right side and was not clogged rotates to directly below the water injection pipe 3, thereby performing sand filtration work with high-pressure water. The clogged sand filter 8 rotates from the left side to directly below the cleaning hole 9, and the clogged sand filter is blocked by the sealing component. The lower end of the sand hole 7 is sealed, and then the sealing cover plate 10 is opened so that the blocked sand screen 8 can be cleaned through the cleaning hole 9. After cleaning, the sealing cover plate 10 is closed, and the sealing component returns to its original position downwards, ending the sealing of the lower end of the sand hole 7, which is convenient for the next exchange. In this invention, when one sand screen 8 intercepts sand particles, the other sand screen 8 can be cleaned through the cleaning hole 9, thereby achieving non-stop maintenance, eliminating the well shutdown time caused by cleaning the sand screen 8, ensuring the continuity of water injection operation, and by using two sand screens 8 alternately, the blocked sand screen 8 can be cleaned in time, extending the service life of the sand screen 8.

[0025] Example 2: Based on Example 1 above, as follows Figure 1 As shown, the diameter of the sand-proof bucket 2 is larger than the diameter of the water injection pipe 3, and the thickness of the sand-proof mesh 8 is smaller than the thickness of the sand-proof disc 4.

[0026] The working principle and beneficial effects of the above technical solution are as follows: the diameter of the sand-proof bucket 2 is not less than twice the diameter of the water injection pipe 3, so that the sand-proof bucket 2 can accommodate the sand-proof disc 4 with two sand-proof holes 7. The sand-proof mesh 8 is installed in the sand-proof hole 7. The sand-proof mesh 8 is located near the upper end of the sand-proof hole 7, which facilitates the cleaning of the sand-proof mesh 8.

[0027] Example 3: Based on Example 1 or 2, such as Figure 1 , Figure 8 As shown, several support components are arranged in a circular array about the central axis of the sandproof disc 4. The support components include a support sleeve 11, the lower end of which is connected to the bottom wall of the sandproof barrel 2. A support spring 12 is installed inside the support sleeve 11, and a support column 13 is installed at the upper end of the support spring 12. The upper end of the support column 13 extends to the bottom of the sandproof disc 4 and a positioning ball 14 is rotatably installed. The bottom wall of the sandproof disc 4 is provided with positioning holes corresponding to the positioning ball 14.

[0028] The working principle and beneficial effects of the above technical solution are as follows: At least three sets of support components are provided. The lower end of the support sleeve 11 is fixedly connected to the bottom wall of the sandproof tank 2. A support spring 12 is installed inside the support sleeve 11. A support column 13 is installed at the upper end of the support spring 12. The positioning ball 14 at the upper end of the support column 13 cooperates with the positioning hole at the bottom of the sandproof disc 4. Multiple support components provide stable support for the sandproof disc 4, ensuring uniform force distribution at the bottom of the sandproof disc 4 and preventing it from tilting. When water is injected, the sandproof disc 4 slides downwards under the downward pressure of the high-pressure water flow, compressing the support spring 12 while providing sufficient elasticity. The supporting force ensures that the positioning ball 14 is positioned within the positioning hole, accurately positioning the sandproof disc 4. This, combined with the engagement of the second sealing plate 18 and the sealing groove 19 in the sealing assembly, prevents the sandproof disc 4 from shifting or rotating under the impact of water flow. When the drive mechanism drives the first rotating shaft 5 to rotate, the first rotating shaft 5 causes the sandproof disc 4 to rotate within the sandproof barrel 2. The positioning ball 14 separates from the positioning hole and rotates on the upper end of the support column 13, while simultaneously rolling on the lower surface of the sandproof disc 4. Rolling friction replaces sliding friction, reducing the rotational resistance of the sandproof disc 4, decreasing wear, and extending its service life.

[0029] Example 4: Based on any one of Examples 1-3, such as Figure 1 , Figure 6 , Figure 7As shown, sealing components are symmetrically arranged on the left and right sides of the first rotating shaft 5. The sealing components include a first sealing plate 15. The upper end of the first sealing plate 15 is connected to the inner wall of the upper end of the sandproof barrel 2. The front and rear ends of the first sealing plate 15 are respectively connected to the inner walls of the front and rear sides of the sandproof barrel 2. A sliding cavity 16 is provided in the first sealing plate 15. A compression spring 17 is provided in the sliding cavity 16. One end of the compression spring 17 is connected to the top wall of the sliding cavity 16. The other end of the compression spring 17 is connected to the second sealing plate 18. The second sealing plate 18 is slidably connected to the inner wall of the sliding cavity 16. The length of the second sealing plate 18 is equal to the length of the first sealing plate 15. A sealing groove 19 corresponding to the second sealing plate 18 is provided on the upper surface of the sandproof disc 4. The lower end of the second sealing plate 18 is located in the sealing groove 19.

[0030] The working principle and beneficial effects of the above technical solution are as follows: The first sealing plate 15 has a U-shaped frame structure. The upper end of the first sealing plate 15 is connected to the inner wall of the upper end of the sandproof barrel 2. A compression spring 17 is installed in the sliding cavity 16 of the first sealing plate 15. The compression spring 17 is in a compressed state. A second sealing plate 18 is installed at the lower end of the compression spring 17. The length of the second sealing plate 18 is the same as the length of the first sealing plate 15. Under the guidance of the inner wall of the sliding cavity 16 and the elastic force of the compression spring 17, the lower end of the second sealing plate 18 is precisely embedded in the sealing groove 19 on the upper surface of the sandproof disc 4, thereby forming a sealing structure on the left and right sides of the first rotating shaft 5. This ensures that the high-pressure water flowing in from the water injection pipe 3 can only flow to the wellhead body 1 through the sandproof hole 7 on the left side. When the sandproof mesh 8 on the left side is blocked by sand particles, the high-pressure water flow can push the sandproof mesh 8 downward. The sandproof mesh 8 drives the sandproof disc 4 to slide downward synchronously. The sandproof disc 4 drives the first rotating shaft 5. Sliding downwards, the first rotating shaft 5 drives the sliding plate 6 to slide downwards on the outer wall of the water injection pipe 3. At the same time, the compressed spring 17 drives the second sealing plate 18 to move downwards through the reset elastic force until the second sealing plate 18 separates from the sealing groove 19. At this time, under the action of the drive mechanism, the first rotating shaft 5 rotates 180°, thereby driving the sandproof disc 4 to rotate 180°, so that the unblocked sandproof mesh 8 rotates to directly below the water injection pipe 3, and the high-pressure water flow can flow downwards through the unblocked sandproof mesh 8. At this time, under the elastic force of the support spring 12, the sandproof disc 4 can return to its original position, and the second sealing plate 18 is re-clamped into the sealing groove 19. Then, the sealing component seals the lower end of the blocked sandproof mesh 8, and the sealing cover plate 10 can be opened for cleaning. During the cleaning process, the sealing of the two second sealing plates 18 and the sealing of the sealing component can prevent the high-pressure water flow from flowing out of the cleaning hole 9, reducing the leakage of high-pressure water.

[0031] Example 5: Based on Example 4, such as Figure 1 , Figure 3 , Figure 4As shown, the drive mechanism includes a drive assembly and a transmission assembly. The drive assembly includes a fixed plate 20, which is horizontally disposed inside the water injection pipe 3. One end of the fixed plate 20 is fixedly connected to the inner wall of the water injection pipe 3. A second rotating shaft 21 is rotatably disposed inside the fixed plate 20. Several fan blades 22 are disposed at the upper end of the second rotating shaft 21. A first bevel gear 23 is disposed at the lower end of the second rotating shaft 21. A third rotating shaft 24 is rotatably disposed on the side wall of the water injection pipe 3. The third rotating shaft 24 is perpendicular to the second rotating shaft 21. A second bevel gear 25 is disposed at one end of the third rotating shaft 24, which meshes with the first bevel gear 23. The other end of the third rotating shaft 24 extends to the outside of the water injection pipe 3 and is provided with a third bevel gear 26. The third bevel gear 26 drives the first rotating shaft 5 to rotate through the transmission assembly. The transmission assembly includes a mounting plate 27, on which a fourth rotating shaft 28 is mounted. The central axis of the fourth rotating shaft 28 is on the same vertical line as the central axis of the first rotating shaft 5. A fourth bevel gear 29 is mounted on the upper end of the fourth rotating shaft 28, meshing with a third bevel gear 26. A crossbar 30 is mounted on the lower end of the fourth rotating shaft 28, perpendicular to the fourth rotating shaft 28. A fixed shaft 31 is mounted on the end of the crossbar 30 away from the fourth rotating shaft 28. A first pawl 32 is rotatably mounted on the fixed shaft 31. A torsion spring 33 is mounted on the fixed shaft 31, with one end connected to the fixed shaft 31 and the other end connected to the first pawl 32. A rotating ring 34 is rotatably mounted on the first rotating shaft 5 near its upper end, and the rotating ring 34 is externally fixed. A first ratchet 35 is provided, and a first pawl 32 engages with the external teeth of the first ratchet 35. A spring-loaded spring 36 is provided on the outside of the rotating ring 34. One end of the spring-loaded spring 36 is connected to the outer wall of the rotating ring 34, and the other end is connected to the upper surface of the sliding plate 6. A second ratchet 37 is fixedly provided on the upper end of the first rotating shaft 5. The second ratchet 37 is located inside the first ratchet 35, and the teeth of the second ratchet 37 are opposite in direction to the teeth of the first ratchet 35. A second pawl 38 is provided on the inner wall of the first ratchet 35. One end of the second pawl 38 is hinged to the inner wall of the first ratchet 35, and the other end engages with the external teeth of the second ratchet 37. The second pawl 38 is connected to the inner wall of the first ratchet 35 near the middle position through a spring wire 39.

[0032] The working principle and beneficial effects of the above technical solution are as follows: During water injection, the high-pressure water flow in the water injection pipe 3 can drive the fan blade 22 to rotate. The rotation of the fan blade 22 drives the second rotating shaft 21 to rotate within the fixed plate 20, and drives the first bevel gear 23 to rotate synchronously. The rotation of the first bevel gear 23 drives the second bevel gear 25 to rotate. The rotation of the second bevel gear 25 drives the third bevel gear 26 to rotate through the third rotating shaft 24. The rotation of the third bevel gear 26 drives the first rotating shaft 5 to rotate through the transmission assembly. Specifically, the third bevel gear 26 meshes with the fourth bevel gear 29, thereby driving the fourth rotating shaft 28 to rotate on the mounting plate 27 through the fourth bevel gear 29. The rotation of the fourth rotating shaft 28 drives the crossbar 30 to rotate. The crossbar 30 drives the fixed shaft 31 to rotate. The fixed shaft 31 is parallel to the first rotating shaft 5. A first pawl 32 is provided on the fixed shaft 31. Under the action of the torsion spring 33, the first pawl 32 engages with the teeth of the first ratchet 35, thereby driving the first ratchet 35 to rotate counterclockwise. The rotation of the first ratchet 35 drives the rotating ring 34 to rotate on the first rotating shaft 5. The rotating ring 34 drives one end of the spring 36 to rotate, causing the spring 36 to wind up and compress. Since the teeth of the second ratchet 37 are opposite to the teeth of the first ratchet 35, the second ratchet 37 does not rotate when the first ratchet 35 rotates counterclockwise. When the spring 36 is compressed to its maximum extent, the fan blade 22 stops rotating. The fan blade 22 adopts a streamlined design and can be selected with 3 blades. The fan blade 22 has little impact on the water injection pressure drop, which is far lower than the allowable water injection pressure drop at the wellhead, so it will not affect the normal water injection efficiency.When the sand screen 8 on the left side becomes clogged, under the impact of the high-pressure water flow, the sand screen 8 on the left side causes the sand screen disc 4 to slide downwards inside the sand screen barrel 2. The support spring 12 is compressed, and the sand screen disc 4 causes the first rotating shaft 5 to slide downwards. The first rotating shaft 5 drives the first ratchet 35 and the spring 36 to move downwards through the rotating ring 34, causing the first pawl 32 to gradually separate from the first ratchet 35. After the first pawl 32 separates from the first ratchet 35, the sand screen disc 4 continues to slide downwards until the second sealing plate 18 separates from the sealing groove 19. At this time, under the elastic force of the spring 36, the rotating ring 34 rotates clockwise on the outer wall of the first rotating shaft 5. The rotating ring 34 drives the first ratchet 35 to rotate clockwise, and the first ratchet 35 drives the second pawl 38 to rotate clockwise. Under the elastic force of spring wire 39, 8 engages with the teeth of the second ratchet 37, thereby driving the second ratchet 37 to rotate clockwise. The second ratchet 37 drives the first rotating shaft 5 to rotate clockwise. The spring spring 36 can be selected according to the actual use scenario to ensure that under the elastic force of the spring spring 36, the first rotating shaft 5 can drive the sandproof disc 4 to rotate 180° clockwise, so that the unblocked sandproof screen 8 on the right side rotates to directly below the water injection pipe 3, and the blocked sandproof screen 8 on the left side rotates to directly below the cleaning hole 9. Then, the high-pressure water flow can smoothly pass through the unblocked sandproof screen 8. Under the elastic force of the support spring 12, the positioning ball 14 pushes the sandproof disc 4 back to its original position, and the lower end of the second sealing plate 18 is re-embedded into the corresponding sealing groove 19 to achieve the sealing function. At the same time, the sandproof disc... 4 drives the first rotating shaft 5 to slide upward. The first rotating shaft 5 drives the first ratchet 35 to move upward through the rotating ring 34, so that the first pawl 32 re-engages into the teeth of the first ratchet 35 for next use. By setting a drive mechanism, when the left sand screen 8 is blocked, the drive mechanism can drive the first rotating shaft 5 to rotate 180°, so that the sand screen 4 rotates 180° in the sand screen barrel 2, realizing the position change of the two sand screens 8. The unblocked sand screen 8 rotates to the bottom of the water injection pipe 3, ensuring that the high pressure water flows smoothly through the sand screen 8 to the wellhead body 1. At the same time, the blocked sand screen 8 rotates to the bottom of the cleaning hole 9, which is convenient for cleaning or replacement without stopping the machine. It will not affect the water injection operation on the left side of the sand screen 4, ensuring the continuity of the water injection operation. This invention increases the pressure difference between the upper and lower sides of the blocked sand-proof mesh 8, causing the sand-proof disc 4 to move downwards. Then, under the action of the spring 36, it rotates 180°. The sealing component then seals the sand-proof mesh 8 below the cleaning hole 9, thus cleaning the sand-proof mesh 8. Compared to existing technologies, this invention does not require shutting down the water injection pipeline, ensuring the continuity and stability of water injection. Furthermore, the sealing component prevents water leakage, improving project reliability. Field tests showed that this device operated continuously for 30 days in water with a sand content of 0.5%, completing 6 automatic cleanings of the sand-proof mesh, each cleaning taking less than 5 minutes. In contrast, existing devices require 6 shutdowns for cleaning under the same conditions, each shutdown taking 30 minutes, resulting in a total impact on water injection time of 180 minutes.

[0033] Example 6: Based on Example 5, such as Figure 1 , Figure 2 As shown, the transmission assembly is covered with a dust cover 40.

[0034] The working principle and beneficial effects of the above technical solution are as follows: one side of the dust cover 40 is connected to the outer wall of the water injection pipe 3, and the other side of the dust cover 40 is connected to the outer wall of the sandproof bucket 2. By setting the dust cover 40, dust can be prevented from accumulating on the outside of the transmission component, ensuring the transmission reliability of the transmission component and extending the service life of the transmission component.

[0035] Example 7: Based on any one of Examples 1-6, such as Figure 1 , Figure 2 , Figures 5-8 As shown, the sealing assembly includes a sealing seat 41, which is frustum-shaped and located directly below the sandproof mesh 8. An electric push rod 42 is installed on the bottom wall of the sandproof barrel 2. A drive plate 43 is installed at the output end of the electric push rod 42. A drive rod 44 is installed on the upper surface of the drive plate 43. The upper end of the drive rod 44 passes through the bottom wall of the sandproof barrel 2 and is connected to the sealing seat 41. The drive rod 44 and the bottom wall of the sandproof barrel 2 are connected in a sealed sliding connection. A drain hole 45 is installed on the upper side wall of the sandproof barrel 2 away from the water injection pipe 3. The drain hole 45 is connected to the space above the sandproof disc 4. A sealing plate 46 is installed outside the drain hole 45. The sealing plate 46 is connected in a sliding connection with the side wall of the sandproof barrel 2. The lower end of the sealing plate 46 is connected to the drive plate 43 through a connecting rod 47. A connecting hole 48 is opened in the sealing plate 46. The connecting hole 48 is located diagonally below the drain hole 45. A baffle 49 is provided below the sealing seat 41. The center of the baffle 49 is slidably connected to the outer wall of the drive rod 44. A connecting spring 50 is provided between the baffle 49 and the sealing seat 41. One end of the connecting spring 50 is connected to the upper surface of the baffle 49, and the other end of the connecting spring 50 is connected to the lower surface of the sealing seat 41. A sealing barrel 51 is installed between the sandproof disc 4 and the cleaning hole 9. The upper end of the sealing barrel 51 is connected to the inner wall of the upper end of the sandproof barrel 2. The inner diameter of the sealing barrel 51 is larger than the diameter of the cleaning hole 9. The central axis of the sealing barrel 51 and the central axis of the cleaning hole 9 are on the same vertical line. A distance sensor is installed on the upper surface of the sealing seat 41. The distance sensor is used to detect the distance from the upper surface of the sealing seat 41 to the lower surface of the sandproof mesh 8. A speed sensor is installed on the first rotating shaft 5. The speed sensor is used to detect the rotation speed of the first rotating shaft 5. A controller is installed outside the sandproof barrel 2. The controller is electrically connected to the distance sensor, the speed sensor and the electric push rod 42 respectively.

[0036] The working principle and beneficial effects of the above technical solution are as follows: The speed sensor is used to detect the speed of the first rotating shaft 5. When the speed sensor detects that the speed of the first rotating shaft 5 is greater than 0, it waits for a preset time. After the preset time, the controller controls the electric push rod 42 to retract. The preset time (which can be set according to the speed of the first rotating shaft 5) is not less than the time required for the first rotating shaft 5 to rotate 180°. This allows the blocked sand screen 8 to rotate to directly below the cleaning hole 9 before the electric push rod 42 retracts. The retraction of the electric push rod 42 can drive the drive plate 43 to move upward. The drive plate 43 drives the drive rod 44 to slide upward. The drive rod 44 drives the sealing seat 41 to move upward. The sealing seat 41 gradually slides to the lower end of the sand hole 7. The upper end is frustum-shaped, and the diameter of the upper end of the sealing seat 41 is smaller than the diameter of the lower end. Therefore, during the rising process of the sealing seat 41, the contact between the sealing seat 41 and the sandproof hole 7 can correct the position of the sandproof hole 7 on the right side, so that the sandproof hole 7 on the right side is aligned with the cleaning hole 9. As the sealing seat 41 enters the sandproof hole 7, the sealing seat 41 gradually seals the lower end of the sandproof hole 7. With the cooperation of the second sealing plate 18 and the sealing groove 19, the space above the sandproof hole 7 on the right side is sealed, and the high-pressure water flow on the left side cannot enter the space above the sandproof hole 7 on the right side, thus avoiding leakage of high-pressure water flow. At the same time as the drive plate 43 moves upward, the drive plate 43 can drive the sealing plate 46 to slide upward along the outer wall of the sandproof barrel 2 through the connecting rod 47. This allows the connecting hole 48 to gradually connect with the drain hole 45. Simultaneously, the sealing seat 41 slides upwards within the sand-proof hole 7, squeezing out the residual water flow within the sand-proof hole 7. This causes the water to flow upwards through the sand-proof mesh 8, impacting it and rinsing it. The flushed sand particles then flow towards the drain hole 45 and finally through the connecting hole 48 to the outside of the sand-proof bucket 2, achieving automatic cleaning of the sand-proof mesh 8. A distance sensor is installed on the sealing seat 41 to detect the distance from the upper surface of the sealing seat 41 to the lower surface of the right-side sand-proof mesh 8. As the sealing seat 41 moves upwards, the distance between the sealing seat 41 and the right-side sand-proof mesh 8 gradually decreases. When the distance to the lower surface of the net 8 is less than the preset distance, the controller controls the electric push rod 42 to extend. The electric push rod 42 drives the drive plate 43 to move downward to return to its original position. The drive plate 43 drives the sealing seat 41 and the sealing plate 46 to return to their original positions through the drive rod 44. The sealing seat 41 separates from the sandproof hole 7 and does not block the rotation of the sandproof disc 4. The connecting hole 48 and the drain hole 45 are no longer connected. The sealing plate 46 re-seals the drain hole 45 to prevent high-pressure water from flowing out of the drain hole 45, thus ending the cleaning of the sandproof net 8 and waiting for the next cleaning of the sandproof net 8. By setting the preset distance, which is greater than 0, the sealing seat 41 is prevented from directly contacting the sandproof net 8, and the sandproof net 8 will not be damaged by impact, thus extending the service life of the sandproof net 8.In addition, the electric push rod 42 can also be manually controlled. When the staff regularly inspects the right-side sandproof mesh 8, the staff first manually controls the electric push rod 42 to retract, so that the sealing seat 41 seals the lower end of the sandproof hole 7. The sealing seat 41 rises, which can drive the baffle 49 to rise synchronously through the connecting spring 50. The diameter of the baffle 49 is larger than the diameter of the sandproof hole 7. When the baffle 49 contacts the lower surface of the sandproof disc 4, the baffle 49 can seal the lower end of the sandproof hole 7, improving the sealing performance of the lower end of the right-side sandproof hole 7 and further preventing the leakage of high-pressure water. Then the sealing seat 41 can continue to move upward, squeezing out the water in the sandproof hole 7. The connecting spring 50 is gradually stretched. When the connecting spring 50 is stretched to the preset length, as the sealing seat 41 continues to move upward... The sealing seat 41 moves upward via the connecting spring 50, causing the baffle 49 to move upward. The baffle 49 then moves the sand-proof disc 4 upward, bringing its upper surface into contact with the lower end of the sealing barrel 51. At this point, the sealing cover 10 is opened, allowing inspection of the right-side sand-proof mesh 8 through the cleaning hole 9. The right-side sand-proof mesh 8 can be cleaned or replaced as needed. After inspection, the sealing cover 10 is closed, and the electric push rod 42 is manually extended and returned to its original position, separating the sealing seat 41 from the lower end of the sand-proof hole 7 for automatic cleaning next time. By setting the sealing barrel 51, the sealing effect on the sand-proof hole 7 is further improved, preventing high-pressure water from the left side of the sand-proof barrel 2 from flowing out through the cleaning hole 9, saving resources, and further ensuring the sealing performance and pressure stability during the water injection process.

[0037] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to 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 invention.

[0038] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., 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, an electrical connection, or a connection that allows communication between them; 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, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A sand-control and water injection wellhead device for oil production, characterized in that, include: The wellhead body (1) is connected to a sand-proof bucket (2) at its upper end. A water injection pipe (3) is connected to the upper end of the sand-proof bucket (2). A sand-proof disc (4) is installed inside the sand-proof bucket (2). The bottom of the sand-proof disc (4) is supported by several support components. A first rotating shaft (5) is fixedly installed at the center of the sand-proof disc (4). The upper end of the first rotating shaft (5) extends to the outside of the sand-proof disc (4) and is rotatably connected to a sliding plate (6). The sliding plate (6) is slidably connected to the outer wall of the water injection pipe (3). A driving mechanism is installed on the water injection pipe (3). The driving mechanism is used to drive... The first rotating shaft (5) rotates, and sand-proof holes (7) are symmetrically arranged on the left and right sides of the sand-proof disc (4). Sand-proof mesh (8) is installed inside the sand-proof hole (7). The central axis of one sand-proof hole (7) is on the same straight line as the central axis of the water injection pipe (3) and the central axis of the wellhead body (1). A cleaning hole (9) is set directly above the other sand-proof hole (7). The cleaning hole (9) is set at the upper end of the sand-proof barrel (2). A sealing cover plate (10) is set outside the cleaning hole (9). A sealing component is set directly below the cleaning hole (9). The sealing component is used to seal the lower end of the sand-proof hole (7).

2. The sand control and water injection wellhead device for oil production according to claim 1, characterized in that, The diameter of the sand-proof bucket (2) is greater than the diameter of the water injection pipe (3), and the thickness of the sand-proof net (8) is less than the thickness of the sand-proof disc (4).

3. The sand control and water injection wellhead device for oil production according to claim 1, characterized in that, Several support components are arranged in a ring array about the central axis of the sandproof disc (4). The support components include a support sleeve (11), the lower end of which is connected to the bottom wall of the sandproof barrel (2). A support spring (12) is provided inside the support sleeve (11), and a support column (13) is provided at the upper end of the support spring (12). The upper end of the support column (13) extends to the bottom of the sandproof disc (4) and a positioning ball (14) is rotatably provided. The bottom wall of the sandproof disc (4) is provided with positioning holes corresponding to the positioning ball (14).

4. The sand control and water injection wellhead device for oil production according to claim 1, characterized in that, The first rotating shaft (5) is symmetrically equipped with sealing components on the left and right sides. The sealing components include a first sealing plate (15). The upper end of the first sealing plate (15) is connected to the inner wall of the upper end of the sandproof barrel (2). The front and rear ends of the first sealing plate (15) are respectively connected to the inner walls of the front and rear sides of the sandproof barrel (2). A sliding cavity (16) is provided in the first sealing plate (15). A compression spring (17) is provided in the sliding cavity (16). One end of the compression spring (17) is connected to the top wall of the sliding cavity (16). The other end of the compression spring (17) is connected to the second sealing plate (18). The second sealing plate (18) is slidably connected to the inner wall of the sliding cavity (16). The length of the second sealing plate (18) is equal to the length of the first sealing plate (15). A sealing groove (19) corresponding to the second sealing plate (18) is provided on the upper surface of the sandproof disc (4). The lower end of the second sealing plate (18) is located in the sealing groove (19).

5. The sand control and water injection wellhead device for oil production according to claim 1, characterized in that, The drive mechanism includes a drive assembly and a transmission assembly. The drive assembly includes a fixed plate (20), which is horizontally set inside the water injection pipe (3). One end of the fixed plate (20) is fixedly connected to the inner wall of the water injection pipe (3). A second rotating shaft (21) is rotatably set inside the fixed plate (20). Several fan blades (22) are set at the upper end of the second rotating shaft (21). A first bevel gear (23) is set at the lower end of the second rotating shaft (21). A third rotating shaft (24) is rotatably set on the side wall of the water injection pipe (3). The third rotating shaft (24) is perpendicular to the second rotating shaft (21). A second bevel gear (25) is set at one end of the third rotating shaft (24). The second bevel gear (25) meshes with the first bevel gear (23). The other end of the third rotating shaft (24) extends to the outside of the water injection pipe (3) and is set with a third bevel gear (26). The third bevel gear (26) drives the first rotating shaft (5) to rotate through the transmission assembly.

6. The sand control and water injection wellhead device for oil production according to claim 5, characterized in that, The transmission assembly includes a mounting plate (27), on which a fourth rotating shaft (28) is mounted. The central axis of the fourth rotating shaft (28) is on the same vertical line as the central axis of the first rotating shaft (5). A fourth bevel gear (29) is mounted on the upper end of the fourth rotating shaft (28), and the fourth bevel gear (29) meshes with a third bevel gear (26). A crossbar (30) is mounted on the lower end of the fourth rotating shaft (28), and the crossbar (30) is perpendicular to the fourth rotating shaft (28). A fixed shaft (31) is mounted on the end of the crossbar (30) away from the fourth rotating shaft (28). A first pawl (32) is rotatably mounted on the fixed shaft (31). A torsion spring (33) is mounted on the fixed shaft (31), and one end of the torsion spring (33) is connected to the fixed shaft (31). The other end of the torsion spring (33) is connected to the first pawl (32). A rotating ring (34) is rotatably mounted near the upper end of the first rotating shaft (5). A first ratchet (35) is fixedly installed in the first ratchet (35), and a first pawl (32) engages with the external teeth of the first ratchet (35). A spring spring (36) is installed on the outside of the rotating ring (34). One end of the spring spring (36) is connected to the outer wall of the rotating ring (34), and the other end of the spring spring (36) is connected to the upper surface of the sliding plate (6). A second ratchet (37) is fixedly installed on the upper end of the first rotating shaft (5). The second ratchet (37) is located inside the first ratchet (35), and the teeth of the second ratchet (37) are opposite in direction to the teeth of the first ratchet (35). A second pawl (38) is installed on the inner wall of the first ratchet (35). One end of the second pawl (38) is hinged to the inner wall of the first ratchet (35), and the other end of the second pawl (38) engages with the external teeth of the second ratchet (37). The second pawl (38) is connected to the inner wall of the first ratchet (35) near the middle position through a spring wire (39).

7. The sand control and water injection wellhead device for oil production according to claim 6, characterized in that, The transmission assembly is covered with a dust cover (40).

8. The sand control and water injection wellhead device for oil production according to claim 1, characterized in that, The sealing assembly includes a sealing seat (41), which is frustum-shaped and located directly below the sandproof net (8). An electric push rod (42) is installed on the bottom wall of the sandproof bucket (2). A drive plate (43) is installed at the output end of the electric push rod (42). A drive rod (44) is installed on the upper surface of the drive plate (43). The upper end of the drive rod (44) passes through the bottom wall of the sandproof bucket (2) and is connected to the sealing seat (41). The drive rod (44) and the bottom wall of the sandproof bucket (2) are connected in a sealed sliding manner at the penetration position. Next, a drain hole (45) is set on the upper side wall of the sandproof bucket (2) away from the water injection pipe (3). The drain hole (45) is connected to the space above the sandproof disc (4). A sealing plate (46) is set outside the drain hole (45). The sealing plate (46) is slidably connected to the side wall of the sandproof bucket (2). The lower end of the sealing plate (46) is connected to the drive plate (43) through the connecting rod (47). A connecting hole (48) is opened in the sealing plate (46). The connecting hole (48) is located diagonally below the drain hole (45).

9. A sand control and water injection wellhead device for oil production according to claim 8, characterized in that, A baffle (49) is provided below the sealing seat (41). The center of the baffle (49) is slidably connected to the outer wall of the drive rod (44). A connecting spring (50) is provided between the baffle (49) and the sealing seat (41). One end of the connecting spring (50) is connected to the upper surface of the baffle (49), and the other end of the connecting spring (50) is connected to the lower surface of the sealing seat (41).

10. A sand control and water injection wellhead device for oil production according to claim 9, characterized in that, A sealing barrel (51) is set between the sandproof disc (4) and the cleaning hole (9). The upper end of the sealing barrel (51) is connected to the inner wall of the upper end of the sandproof barrel (2). The inner diameter of the sealing barrel (51) is larger than the diameter of the cleaning hole (9). The central axis of the sealing barrel (51) and the central axis of the cleaning hole (9) are on the same vertical line.

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