Oil field underground water control screen pipe

Abstract

The invention relates to the technical field of water control screen pipes, and discloses an oil field underground water control screen pipe which comprises a center pipe, the top end of the center pipe is communicated with an upper pipe, the bottom end of the center pipe is communicated with a lower pipe, a first filter plate is arranged in the center pipe, and a second filter plate is arranged at the bottom of the first filter plate. A first filter hole and a second filter hole are formed in the surface of the first filter plate and the surface of the second filter plate respectively, a plurality of cleaning rods are fixedly connected to the bottom surface of the first filter plate, a cleaning assembly is inserted into the first filter plate, a fixing ring is fixedly mounted in the upper pipe, and a water control device is fixedly mounted on the inner side of the fixing ring. By arranging the cleaning assembly, fluid impurities such as sludge can be prevented from penetrating through the filtering holes to enter the center pipe when the pipeline is in a standing state, meanwhile, a cleaning rod can be inserted into the second filtering holes to clean the second filtering holes, and the filtering effect of the second filtering holes is improved while the fluid circulation rate is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of water control screen pipes, and particularly to an oilfield downhole water control screen pipe. Background Art

[0002] An oilfield downhole water control screen pipe is a key tool for controlling water production during the oil extraction process. It is usually made of high-strength corrosion-resistant metal or composite materials and has a specially designed screen structure. Its core function is to allow crude oil to pass through smoothly while effectively blocking solid particles such as formation sand to prevent them from entering the oil production pipeline and causing blockage or equipment wear. More importantly, through a unique water control mechanism, it can accurately control the water output according to the distribution of oil layers and water layers and the production dynamics, reduce unnecessary water production, improve the efficiency and quality of crude oil extraction, and is widely used in the extraction operations of various water-producing reservoirs, greatly optimizing the overall development efficiency of the oilfield.

[0003] In the existing water control screen pipes, although a screen is provided inside to filter impurities, when the pipeline is not in use, fluid impurities such as silt in the wellbore may enter the inside of the pipeline through the filter holes on the screen plate and cause blockage of the filter holes, affecting the use. Moreover, the traditional pipeline does not have the function of automatically cleaning the filter plate, reducing the use effect. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the present invention provides an oilfield downhole water control screen pipe, which solves the problems that in the static state, fluid impurities such as silt often enter the inside of the pipeline, block the filter plate, and it is not convenient to clean the filter plate.

[0005] To achieve the above objectives, the present invention is realized through the following technical solutions: An oilfield downhole water control screen pipe includes a central pipe. The top end of the central pipe is connected to an upper pipe, and the bottom end of the central pipe is connected to a lower pipe. A first filter plate is provided inside the central pipe, and a second filter plate is provided at the bottom of the first filter plate. First filter holes and second filter holes are respectively formed on the surfaces of the first filter plate and the second filter plate. A plurality of cleaning rods are fixedly connected to the bottom surface of the first filter plate, and a cleaning assembly is inserted into the first filter plate. A fixing ring is fixedly installed inside the upper pipe, and a water control device is fixedly installed inside the fixing ring.

[0006] Through the above technical solutions, the first filter plate and the second filter plate are attached to each other in the static state, thereby preventing fluid impurities such as silt from entering the inside of the central pipe. And when the first filter plate is attached to the second filter plate, the cleaning rods can be inserted into the second filter holes, thereby cleaning the impurities stuck in the second filter holes, ensuring the rate of fluid flowing through the second filter holes while also ensuring the normal discharge of the entire pipeline.

[0007] Preferably, the cleaning component includes a sliding rod, a connecting plate, a telescopic spring and an impact plate. The two sliding rods are fixedly inserted into the first filter plate. The two connecting plates are respectively fixedly installed at the tops of the two sliding rods. The two telescopic springs are respectively fixedly installed on the top surfaces of the two connecting plates. The impact plate is fixedly installed between the two sliding rods.

[0008] Preferably, the inner wall of the central pipe is symmetrically provided with movable grooves, and the two telescopic springs are respectively arranged inside the movable grooves.

[0009] Preferably, the surface of the second filter plate is symmetrically provided with movable holes, the sliding rod is arranged inside the movable holes, and the sliding rod is slidably connected with the inner wall of the movable holes.

[0010] Preferably, a fixing rod is fixedly installed inside the central pipe. The bottom surface of the fixing rod is fixedly connected with a detection device. The bottom surface of the detection device is rotatably installed with a rotating shaft. A plurality of fan blades are fixedly connected to the outer surface of the rotating shaft.

[0011] Preferably, a vibrator is fixedly installed on the top surface of the first filter plate. One side of the vibrator is connected with a wire, and one end of the wire is connected with the detection device.

[0012] Preferably, a fine sieve plate is arranged inside the upper pipe, and the fine sieve plate is arranged at the bottom of the fixing ring. Two first fixing blocks are fixedly installed on the inner wall of the upper pipe, and the fine sieve plate is fixedly installed on the top of the first fixing block through a first screw.

[0013] Preferably, two second fixing blocks are fixedly installed on the inner wall of the upper pipe, and the fixing ring is fixedly installed on the top of the second fixing block through a second screw.

[0014] Preferably, the positions of the first filter holes and the second filter holes are staggered from each other, and the cleaning rod is arranged opposite to the position of the second filter holes.

[0015] Working principle: When using this device, the upper pipe and the lower pipe can be installed at both ends of the central pipe, and the upper pipe is connected to an external pipe. When the oil-water mixed fluid enters the inside of the central pipe through the lower pipe, the fluid can impact the impact plate. The impact plate will push the first filter plate upward through the sliding rod when being impacted, and then the first filter plate and the second filter plate can be separated. At this time, the fluid can enter the inside of the central pipe through the second filter holes and the first filter holes respectively, and at the same time, the second filter holes and the first filter holes can filter the impurities in the fluid.

[0016] When the fluid enters the interior of the central pipe, the fan blades are impacted by the fluid and rotate. The fan blades drive the rotating shaft to rotate. The detection device can detect the rotation speed of the rotating shaft, and thus can detect the flow rate of the fluid. When the flow rate is small, it indicates that the first filter holes on the surface of the first filter plate may be blocked by impurities. The detection device sends a signal to the vibrator through a wire, and the vibrator can vibrate the first filter plate to clean the impurities stuck in the first filter holes, ensuring the normal flow rate of the fluid. When the pipeline is in a static state as a whole, the telescopic spring can push the connecting plate downward through the reverse force. The connecting plate pushes the sliding rod downward, and the sliding rod can drive the first filter plate downward, making the first filter plate fit with the second filter plate, and making the cleaning rod insert into the interior of the second filter holes, thereby cleaning the impurities in the second filter holes and preventing the second filter holes from being blocked and affecting the flow rate of the fluid.

[0017] The present invention provides an oilfield downhole water control screen pipe, which has the following beneficial effects: 1. By setting up a cleaning component in the present invention, when the pipeline is in a static state, the telescopic spring can push the connecting plate downward. The connecting plate can further push the sliding rod downward, and the sliding rod drives the first filter plate to fit with the second filter plate. Moreover, the first filter holes and the second filter holes are arranged staggeredly, thereby preventing fluid impurities such as silt from passing through the filter holes and entering the interior of the central pipe when the pipeline is in a static state. And when the first filter plate fits with the second filter plate, the cleaning rod can be inserted into the interior of the second filter holes, thereby cleaning the impurities stuck in the second filter holes, ensuring the fluid flow rate while also increasing the filtering effect of the second filter holes.

[0018] 2. When in use in the present invention, when the fluid continuously moves upward, the flow of the fluid impacts the fan blades. The fan blades rotate when impacted, and the fan blades drive the rotating shaft to rotate. At this time, the detection device can detect the rotation speed of the rotating shaft, and thus can detect the flow rate of the fluid. When the fluid flow rate is low, the detection device can send a signal to the vibrator through a wire, and the vibrator can vibrate the first filter plate. The vibration of the first filter plate can shake off the impurities stuck in the first filter holes, thereby preventing the impurities from getting stuck in the first filter holes and affecting the overall discharge of the pipeline.

[0019] 3. When in use in the present invention, the second screw and the first screw can be removed in sequence. When the second screw is removed, the fixing state of the fixing ring can be released. At this time, the water control device can be removed from the upper pipe for easy maintenance and repair. When the first screw is removed, the fixing state of the fine sieve plate can be released, and thus it is convenient to clean and replace the fine sieve plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a three-dimensional view of the present invention; Figure 2 is an internal schematic diagram of the present invention; Figure 3 Schematic diagram of the first filter plate of the present invention; Figure 4 Schematic diagram of the impact plate of the present invention; Figure 5 Schematic diagram of the movable hole of the present invention; Figure 6 Schematic diagram of the detection device of the present invention; Figure 7 Schematic diagram of the fixing ring of the present invention.

[0021] Among them, 1, central pipe; 2, upper pipe; 3, lower pipe; 4, fixing ring; 5, water control device; 6, fine sieve plate; 7, first filter plate; 8, fixing rod; 9, second filter plate; 10, sliding rod; 11, impact plate; 12, movable groove; 13, connecting plate; 14, telescopic spring; 15, first filter hole; 16, cleaning rod; 17, movable hole; 18, second filter hole; 19, detection device; 20, rotating shaft; 21, fan blade; 22, wire; 23, vibrator; 24, first fixing block; 25, first screw; 26, second fixing block; 27, second screw. Detailed implementation manners

[0022] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] Please refer to the attached Figure 1 - attached Figure 5 , an oilfield downhole water control screen pipe provided by an embodiment of the present invention includes a central pipe 1. The top end of the central pipe 1 is connected to an upper pipe 2, the bottom end of the central pipe 1 is connected to a lower pipe 3. A first filter plate 7 is provided inside the central pipe 1. A second filter plate 9 is provided at the bottom of the first filter plate 7. First filter holes 15 and second filter holes 18 are respectively formed on the surfaces of the first filter plate 7 and the second filter plate 9. A plurality of cleaning rods 16 are fixedly connected to the bottom surface of the first filter plate 7. A cleaning assembly is inserted into the first filter plate 7. A fixing ring 4 is fixedly installed inside the upper pipe 2, and a water control device 5 is fixedly installed inside the fixing ring 4.

[0024] Specifically, the first filter plate 7 and the second filter plate 9 are arranged one above the other. The fluid in the well enters the interior of the central pipe 1 through the lower pipe 3. When the first filter plate 7 is separated from the second filter plate 9, the fluid can flow through the second filter holes 18 and the first filter holes 15 respectively, thereby filtering the fluid in the well. The aperture of the second filter holes 18 is 0.2 mm - 0.5 mm, and the aperture of the first filter holes 15 is 0.1 mm - 0.2 mm. The second filter holes 18 can filter medium coarse sand, and the first filter holes 15 can filter fine sand, thus fully ensuring the quality of fluid filtration and effectively preventing sand grains in the formation from entering the wellbore along with the fluid. The upper and lower ends of the central pipe 1 are provided with external threads, and the top end of the lower pipe 3 and the inner wall of the upper pipe 2 are provided with internal threads, so that the upper pipe 2 and the lower pipe 3 can be hermetically installed at both ends of the central pipe 1 by threads, and then the pipeline can be integrally assembled. In actual use, the upper pipe 2 can be connected to an external discharge pipeline. The second filter plate 9 is fixedly installed inside the central pipe 1, and the first filter plate 7 is movably arranged inside the central pipe 1.

[0025] Please refer to the attached Figure 2 - attached Figure 4 , the cleaning assembly includes a slide bar 10, a connecting plate 13, a telescopic spring 14 and an impact plate 11. Two slide bars 10 are fixedly inserted into the first filter plate 7. Two connecting plates 13 are respectively fixedly installed at the tops of the two slide bars 10. Two telescopic springs 14 are respectively fixedly installed on the top surfaces of the two connecting plates 13. The impact plate 11 is fixedly installed between the two slide bars 10.

[0026] Specifically, when the water-oil mixed fluid enters the interior of the central pipe 1 through the lower pipe 3, the impact plate 11 will be impacted by the fluid. When the impact plate 11 is impacted, it will push the slide bar 10 upward. Since the slide bar 10 is fixedly connected to the first filter plate 7, the first filter plate 7 can be driven to move upward. When the first filter plate 7 moves upward, the first filter plate 7 and the second filter plate 9 can be separated, and then the first filter holes 15 and the second filter holes 18 can be separated, so as to facilitate the fluid to pass through the second filter holes 18 and the first filter holes 15 for filtration. And when the whole pipeline is in a static state, the impact force on the impact plate 11 disappears. At this time, the telescopic spring 14 can push the connecting plate 13 downward through the reverse acting force. The downward movement of the connecting plate 13 can drive the first filter plate 7 to move downward, and the cleaning rod 16 can move downward and insert into the second filter holes 18, thereby cleaning the impurities stuck in the second filter holes 18, ensuring the subsequent filtration effect of the second filter plate 9 and enhancing the practicability of the device.

[0027] Please refer to the attached Figure 2 - attached Figure 3 , the inner wall of the central pipe 1 is symmetrically provided with movable grooves 12, and the two telescopic springs 14 are respectively arranged inside the movable grooves 12.

[0028] Specifically, the two connecting plates 13 respectively extend into the interior of the movable slot 12, and the extension plates are slidably connected to the inner wall of the movable slot 12. Thus, when the spring expands and contracts, the connecting plates 13 can slide inside the movable slot 12, thereby increasing the directivity and stability of the movement of the connecting plates 13. At the same time, the directivity of the up-and-down movement of the first filter plate 7 is also enhanced.

[0029] Please refer to the appendix Figure 5 , the surface of the second filter plate 9 is symmetrically provided with movable holes 17, and the sliding rods 10 are arranged inside the movable holes 17, and the sliding rods 10 are slidably connected to the inner wall of the movable holes 17.

[0030] Specifically, when the impact plate 11 moves upward under the impact of the fluid, it can drive the sliding rods 10 to slide inside the movable holes 17, thereby increasing the directivity and stability of the up-and-down movement of the impact plate 11. At the same time, the stability and directivity of the first filter plate 7 during lifting are also enhanced.

[0031] Please refer to the appendix Figure 2 and the appendix Figure 6 , a fixing rod 8 is fixedly installed inside the central tube 1, the bottom surface of the fixing rod 8 is fixedly connected with a detection device 19, the bottom surface of the detection device 19 is rotatably installed with a rotating shaft 20, and a plurality of fan blades 21 are fixedly connected to the outer surface of the rotating shaft 20.

[0032] Specifically, the detection device 19 of this device is a device for detecting the rotation speed of the rotating shaft 20. In fact, it is a common photoelectric encoder. When the rod rotates, the code disk will rotate accordingly. The photoelectric sensor will generate a series of pulse signals according to the patterns or codes on the code disk. By counting the pulse signals and measuring the time, the rotation speed of the rod can be calculated. The device for detecting the rotation speed of the rod is very common and is widely used in various fields. Therefore, the specific structure and principle will not be elaborated here. When the filtered fluid enters the interior of the central tube 1, it will impact the fan blades 21. When the flow rate of the fluid is large, the rotation speed of the fan blades 21 will also increase, and thus the rotation speed of the rotating shaft 20 will also increase. At this time, the detection device 19 can detect that the flow rate of the fluid is in a normal state, indicating that the first filter holes 15 and the second filter holes 18 on the surfaces of the first filter plate 7 and the second filter plate 9 are in a normal state. When the flow rate in the central tube 1 becomes small, the rotation speed of the fan blades 21 will also become small, and thus the rotation speed of the rotating shaft 20 will also become small. At this time, the detection device 19 will detect that the flow rate of the fluid has become small, which means that impurities may be stuck in the first filter holes 15 on the surface of the first filter plate 7.

[0033] Please refer to the appendix Figure 6 , a vibrator 23 is fixedly installed on the top surface of the first filter plate 7, one side of the vibrator 23 is connected with a wire 22, and one end of the wire 22 is connected to the detection device 19.

[0034] Specifically, when the detection device 19 detects that the fluid flow rate in the central pipe 1 decreases, the detection device 19 can send a signal to the vibrator 23 through the wire 22. The vibrator 23 can vibrate the first filter plate 7. The vibrating first filter plate 7 can shake off the impurities stuck in the first filter holes 15, thereby ensuring the smoothness of the first filter holes 15, ensuring the normal fluid flow rate, and ensuring the discharge of the pipeline. The wire 22 of this device is made of a soft material, so it will not hinder the movement of the first filter plate 7.

[0035] Please refer to the appendix Figure 2 and the appendix Figure 7 , a fine sieve plate 6 is provided inside the upper pipe 2, and the fine sieve plate 6 is arranged at the bottom of the fixing ring 4. Two first fixing blocks 24 are fixedly installed on the inner wall of the upper pipe 2, and the fine sieve plate 6 is fixedly installed on the top of the first fixing blocks 24 through the first screw 25.

[0036] Specifically, the aperture of the fine sieve plate 6 is 0.25 mm - 0.15 mm. The fine sieve plate 6 can filter the impurities with smaller particle sizes in the fluid, further ensuring the quality of the discharged fluid. By removing the first screw 25, the fixing state of the fine sieve plate 6 on the first fixing blocks 24 can be released. At this time, the fine sieve plate 6 can be removed, which is convenient for removing, cleaning, and replacing the fine sieve plate 6.

[0037] Please refer to the appendix Figure 7 , two second fixing blocks 26 are fixedly installed on the inner wall of the upper pipe 2, and the fixing ring 4 is fixedly installed on the top of the second fixing blocks 26 through the second screw 27.

[0038] Specifically, by removing the second screw rod 27, the fixed state of the fixed ring 4 on the second fixed block 26 can be released. At this time, the fixed ring 4 can be removed, which is convenient for maintaining the water control device 5. The water control device 5 of this device is an AICD water control valve, and its principle is as follows: Based on the law of conservation of fluid mechanical energy in Bernoulli's equation, that is, kinetic energy + gravitational potential energy + pressure potential energy equals a constant. The floating plate type AICD water control valve automatically adjusts the up and down movement of the floating plate according to the relationship between fluid viscosity and velocity. For fluids with high viscosity, the flow velocity is slow, the kinetic energy of the fluid above the floating plate is small, and the potential energy is large, which pushes the floating plate downward to increase the fluid flow channel; for fluids with low viscosity (such as water and gas), the flow velocity is fast, the kinetic energy of the fluid above the floating plate is large, and the potential energy is small, so the floating plate moves upward to reduce the flow channel. The fluid impacts the impeller bearing to drive the fluid selector to rotate, and the float moves inside the channel depending on the centripetal force and different fluid densities to control the opening and closing of the production valve. The density of the floating ball is between that of oil and water. It moves towards the direction close to the central axis in fluids with a density lower than its own, and moves towards the direction away from the central axis in fluids with a density higher than its own. When the fluid is oil, the floating ball moves towards the central axis, closing the floating ball channel, generating a pressure difference between the upper and lower ends of the production valve, causing the valve to open, and the fluid to flow into the collection channel; when the fluid is water, the floating ball moves towards the direction away from the central axis, the floating ball channel opens, the pressure difference between the upper and lower ends of the production valve is small, the valve remains closed, and a small amount of fluid flows into the collection channel, thereby controlling the discharge ratio of water and oil.

[0039] Please refer to the attached Figure 3 - attached Figure 5 The positions of the first filter hole 15 and the second filter hole 18 are staggered from each other, and the cleaning rod 16 is arranged opposite to the position of the second filter hole 18.

[0040] Specifically, since the first filter hole 15 and the second filter hole 18 are staggered, when the first filter plate 7 and the second filter plate 9 are in contact, the inner space of the second filter plate 9 is no longer connected to the central tube 1. When the pipeline is in a static state, it can prevent fluids such as silt from entering the interior of the central tube 1. The cleaning rod 16 is arranged opposite to the second filter hole 18. When the first filter plate 7 and the second filter plate 9 are in contact, it can ensure that the cleaning rod 16 is inserted into the second filter hole 18 to clean the impurities stuck inside the second filter hole 18.

[0041] For the usage method of an oilfield downhole water control screen pipe of this application, it includes the following steps: S1. Assemble and install the upper pipe 2 and the lower pipe 3 at the top and bottom of the central tube 1 respectively, so as to integrate the pipeline into a whole pipeline. Install the combined pipeline inside the wellbore and seal it in the designated wellbore to install the whole pipeline. S2. When the pipeline is in use, the oil-water mixture together with impurities will enter the interior of the center through the lower pipe 3. Subsequently, the fluid will impact the impact plate 11. When the impact plate 11 is impacted, it will push the slide rod 10 to move upward. The slide rod 10 drives the first filter plate 7 to move upward, so that the first filter plate 7 and the second filter plate 9 are separated. At this time, the first filter holes 15 and the second filter holes 18 can filter the impurities in the fluid. S3. The filtered fluid will continue to flow upward. The flowing fluid will impact the fan blades 21 inside the central pipe 1. When the fan blades 21 are impacted, they will rotate. The fan blades 21 drive the rotating shaft 20 to rotate. The detection device 19 can detect the rotation speed of the rotating shaft 20. When the rotation speed of the rotating shaft 20 is too small, the detection device 19 sends an electrical signal to the wire 22, and then controls the vibrator 23 to vibrate. The vibrator 23 drives the first filter plate 7 to vibrate, and the vibration of the first filter plate 7 can make the impurities stuck in the first filter holes 15 fall off. S4. The fluid continues to flow upward and enters the interior of the upper pipe 2. Through the fine sieve plate 6 in the upper pipe 2, the fluid can be filtered again. The water control device 5 is opened to control the flow rates of water and oil, and thus adjust the ratio of water and oil output.

[0042] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An oilfield downhole water control screen pipe, comprising a central pipe (1), characterized in that: The top end of the central pipe (1) is communicated with an upper pipe (2), the bottom end of the central pipe (1) is communicated with a lower pipe (3), a first filter plate (7) is arranged inside the central pipe (1), a second filter plate (9) is arranged at the bottom of the first filter plate (7), first filter holes (15) and second filter holes (18) are respectively formed on the surfaces of the first filter plate (7) and the second filter plate (9), a plurality of cleaning rods (16) are fixedly connected to the bottom surface of the first filter plate (7), a cleaning assembly is inserted into the first filter plate (7), a fixing ring (4) is fixedly installed inside the upper pipe (2), and a water control device (5) is fixedly installed on the inner side of the fixing ring (4).

2. The oilfield downhole water control screen pipe according to claim 1, wherein: The cleaning assembly includes sliding rods (10), connecting plates (13), telescopic springs (14) and impact plates (11). The two sliding rods (10) are fixedly inserted into the first filter plate (7). The two connecting plates (13) are respectively fixedly installed at the tops of the two sliding rods (10). The two telescopic springs (14) are respectively fixedly installed on the top surfaces of the two connecting plates (13). The impact plate (11) is fixedly installed between the two sliding rods (10).

3. The oilfield downhole water control screen pipe according to claim 2, characterized in that: Moving grooves (12) are symmetrically formed in the inner wall of the central pipe (1), and the two telescopic springs (14) are respectively arranged inside the moving grooves (12).

4. The oilfield downhole water control screen pipe according to claim 2, characterized in that: Moving holes (17) are symmetrically formed in the surface of the second filter plate (9), the sliding rods (10) are arranged inside the moving holes (17), and the sliding rods (10) are slidably connected to the inner walls of the moving holes (17).

5. The oilfield downhole water control screen pipe according to claim 1, characterized in that: A fixing rod (8) is fixedly installed inside the central pipe (1), a detection device (19) is fixedly connected to the bottom surface of the fixing rod (8), a rotating shaft (20) is rotatably installed on the bottom surface of the detection device (19), and a plurality of fan blades (21) are fixedly connected to the outer surface of the rotating shaft (20).

6. The oilfield downhole water control screen pipe according to claim 5, characterized in that: A vibrator (23) is fixedly installed on the top surface of the first filter plate (7), a wire (22) is connected to one side of the vibrator (23), and one end of the wire (22) is connected to the detection device (19).

7. The water control screen pipe for downhole in oil field according to claim 1, wherein: A fine sieve plate (6) is arranged inside the upper pipe (2), and the fine sieve plate (6) is arranged at the bottom of the fixing ring (4). Two first fixing blocks (24) are fixedly installed on the inner wall of the upper pipe (2), and the fine sieve plate (6) is fixedly installed on the top of the first fixing blocks (24) through a first screw rod (25).

8. The downhole water control screen pipe for oil fields according to claim 1, characterized in that: Two second fixing blocks (26) are fixedly installed on the inner wall of the upper pipe (2), and the fixing ring (4) is fixedly installed on the top of the second fixing blocks (26) through a second screw rod (27).

9. The downhole water control screen pipe for oil field according to claim 1, wherein: The positions of the first filter holes (15) and the second filter holes (18) are staggered from each other, and the cleaning rods (16) are arranged opposite to the positions of the second filter holes (18).

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