An eccentric suction device for a horizontal well

Abstract

The application provides an eccentric suction device for a horizontal well and relates to the technical field of oil extraction. The existing liquid inlet hole opening mode cannot simultaneously meet the maximum oil inlet amount and the reduced air inlet amount. The eccentric suction device comprises an outer pipe, a liquid inlet is arranged on the outer pipe, an eccentric pipe is fixedly connected to the outer pipe, an eccentric part is arranged on one side of the eccentric pipe close to the liquid inlet of the outer pipe, the axis of the eccentric part of the eccentric pipe is located below the axis of the outer pipe, the outer pipe is provided with an air outlet hole located above the eccentric pipe, the lower side of the eccentric part of the eccentric pipe is provided with liquid inlet holes with equal intervals and different heights, and the eccentric pipe is slidably connected with symmetrically distributed arc-shaped baffles. According to the liquid level change in the horizontal well, the amount of the liquid inlet holes blocked by the arc-shaped baffles is synchronously changed, the oil pumping amount is maximized, the amount of the gas entering the eccentric pipe is reduced, and the oil pumping efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of oil production technology, and more particularly to an eccentric suction device for horizontal wells. Background Technology

[0002] During horizontal well production, due to the unique structure of the wellbore, the fluids (crude oil, gas, water, etc.) are distributed differently within the wellbore. Crude oil, with its higher density, typically accumulates in the lower half of the wellbore, while less dense gas occupies the upper half. While this separation is beneficial for gas production, it poses a challenge to the effective lifting of crude oil and can easily lead to gas being sucked into the pump, causing gas lock and other problems. Current methods generally address this issue using an eccentric suction device. Its core design involves an eccentric tube whose axis is not aligned with the wellbore axis, creating a crescent-shaped space between the outer wall of this eccentric tube and the inner wall of the wellbore that gradually increases in size from top to bottom. During operation, due to gravity, crude oil in the wellbore naturally settles and collects at the bottom of this crescent-shaped space. Existing eccentric suction devices typically have an inlet port at the very bottom of the eccentric section of this eccentric tube. Using a suction device, negative pressure is generated within the eccentric tube, drawing the crude oil collected at the bottom of the crescent-shaped space through the lowest inlet port into the tube and lifting it to the surface. Since the density of gas is much lower than that of crude oil, it will rise above the crude oil. Therefore, this method of placing the port only at the lowest point can theoretically achieve the effect of "prioritizing crude oil intake and effectively isolating gas." However, this existing inlet port design has significant technical flaws, specifically in the following two aspects:

[0003] Question 1: If the inlet hole is opened only at the lowest point of the eccentric part of the eccentric tube (the theoretical lowest point) in order to strictly prevent gas intrusion, the number of inlet holes available will be small and the total flow area will be small due to the extremely limited hole layout. This will severely restrict the crude oil intake per unit time, resulting in low oil pumping efficiency and failing to meet the production needs of high-yield horizontal wells.

[0004] Question 2: If additional inlet holes are added in the upper region of the lowest side of the eccentric part in order to improve pumping efficiency and increase production, although the pumping area and flow rate are increased, when the gas content (gas-oil ratio) of the crude oil in the wellbore is high or the production pressure fluctuates, the oil level will drop. Once the level drops to the height of these additional inlet holes, the free gas in the upper part of the wellbore will be directly sucked into the eccentric tube, affecting oil extraction. Summary of the Invention

[0005] This invention provides a self-adjusting eccentric intake device for horizontal wells, thereby solving the technical problem that existing methods of opening inlet holes cannot simultaneously meet the requirements of maximum oil intake and reduced air intake.

[0006] The technical solution of the present invention is: an eccentric suction device for horizontal wells, comprising an outer tube, an inlet provided on the outer tube, an eccentric tube fixedly connected to the outer tube, an eccentric portion provided on the side of the eccentric tube near the inlet of the outer tube, the axis of the eccentric portion of the eccentric tube being located below the axis of the outer tube, an exhaust port provided on the outer tube above the eccentric tube, inlet ports equally spaced and at different heights provided on the lower side of the eccentric portion of the eccentric tube, and symmetrically distributed arc-shaped baffles slidably connected inside the eccentric tube, the symmetrically distributed arc-shaped baffles all serving to block the inlet ports.

[0007] Furthermore, the eccentric tube is fixed with symmetrically distributed limiting semi-rings that together serve to limit the symmetrically distributed arc-shaped baffles.

[0008] Furthermore, the eccentric tube is slidably connected to a sliding frame, the sliding frame is fixedly connected to symmetrically distributed floats located outside the eccentric tube, the sliding frame is fixedly connected to an I-shaped frame located inside the eccentric tube, and the I-shaped frame is slidably connected to symmetrically distributed sliding plates that are respectively hinged to adjacent arc-shaped baffles.

[0009] Furthermore, the float is higher than the lowest point of the arc-shaped baffle.

[0010] Furthermore, the inlet hole is equipped with an interception net for intercepting sand in the oil.

[0011] Furthermore, the eccentric tube is fixedly connected to a sleeve, the sleeve is slidably connected to a first sliding tube, the first sliding tube is fixedly connected to a sealing ring that is slidably connected to the inside of the sleeve, a first tension spring is fixedly connected between the sealing ring and the sleeve, the sleeve is provided with a through hole, the first sliding tube is fixedly connected to a first U-shaped plate, the first U-shaped plate is provided with symmetrically distributed sliding members, the symmetrically distributed sliding members are jointly fixedly connected to a scraper, the scraper is provided with an inner arc-shaped surface coaxial with the eccentric part of the eccentric tube, and the scraper is used to scrape off sand on the outside of the liquid inlet hole.

[0012] Furthermore, the first slide tube is slidably connected to a second slide tube that is slidably connected to the sealing ring. The second slide tube is fixedly connected to a second U-shaped plate. A spring is fixedly connected between the first U-shaped plate and the scraper. The sliding member is provided with an inclined portion. The second U-shaped plate is used to compress the inclined portions of the symmetrically distributed sliding members. The symmetrically distributed sliding members are all slidably connected to the first U-shaped plate. The second slide tube is fixedly connected to a piston that is slidably connected to the sleeve. A second tension spring is fixedly connected between the piston and the sealing ring. The second slide tube communicates with the cavity between the sealing ring and the piston in the sleeve.

[0013] Furthermore, the inner diameter of the second slide tube is larger than the diameter of the through hole.

[0014] Furthermore, the scraper is provided with an outer arc-shaped surface coaxial with the outer tube.

[0015] Furthermore, the longitudinal length of the middle part of the scraper is less than the distance between the lowest side of the eccentric part of the eccentric tube and the lowest side of the inner wall of the liquid inlet of the outer tube.

[0016] The beneficial effects are as follows: This invention adjusts the amount of inlet hole blocked by the arc-shaped baffle according to the change in fluid level in the horizontal well. While maximizing the oil extraction rate, it also reduces the amount of gas entering the eccentric tube, thus improving the oil extraction efficiency. When the oil level in the horizontal well rises, the float rises with the fluid level, causing the arc-shaped baffle to release the blockage of part of the inlet hole, thereby increasing the oil extraction rate. When the fluid level drops, the arc-shaped baffle blocks the additional inlet hole, reducing the amount of gas entering the eccentric tube. During the upward stroke, the characteristic that the orifice size affects the fluid flow velocity is utilized. The sliding component drives the scraper to move upward, causing the scraper to scrape off the sand outside the inlet hole. During the downward stroke, the scraper adheres tightly to the lower side of the inner wall of the outer tube and pushes the sand below the inlet hole out of the outer tube, reducing sand accumulation. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0018] Figure 2 This is a three-dimensional structural cross-sectional view of the present invention;

[0019] Figure 3 This is a three-dimensional structural diagram of the first U-shaped plate and the second U-shaped plate of the present invention;

[0020] Figure 4 This is a three-dimensional structural diagram of the sliding component and scraper of the present invention;

[0021] Figure 5 This is a three-dimensional cross-sectional view of the eccentric tube and sleeve of the present invention;

[0022] Figure 6 This is a three-dimensional structural diagram of the liquid inlet and the arc-shaped baffle of the present invention;

[0023] Figure 7 This is a three-dimensional cross-sectional view of the sealing ring and piston of the present invention.

[0024] The component names and serial numbers in the diagram are as follows: 1-Outer tube, 2-Eccentric tube, 201-Inlet hole, 3-Arc-shaped baffle, 4-Limiting half-ring, 5-Sliding frame, 6-Float, 7-I-shaped frame, 8-Sliding plate, 9-Sleeve, 901-Through hole, 10-First slide tube, 11-Sealing ring, 12-First tension spring, 13-First U-shaped plate, 14-Sliding component, 15-Scraper, 16-Second slide tube, 17-Second U-shaped plate, 18-Piston, 19-Second tension spring. Detailed Implementation

[0025] The preferred technical solution of the present invention will be described in detail below with reference to the accompanying drawings. Example 1

[0026] Existing eccentric suction devices typically have an inlet port located below the eccentric section of the eccentric tube. This allows oil from below the horizontal well to be extracted through the inlet port. Since the density of gas is less than that of oil, the gas will only be above the oil and will not enter the eccentric tube with it. However, the current placement of the inlet port has the following problems: Problem 1: If the inlet port is only located at the bottom of the eccentric section of the eccentric tube, the number of inlet ports is limited, resulting in low oil extraction. Problem 2: If an additional inlet port is located above the bottom of the eccentric section of the eccentric tube, although this increases the oil extraction rate, if the oil contains too much gas, the oil level will be lower than the additional inlet port, causing the gas to be drawn into the eccentric tube along with the oil, thus affecting the oil extraction process.

[0027] An eccentric suction device for horizontal wells, such as Figures 1-6As shown, the device includes an outer tube 1 with a liquid inlet on its right side. An eccentric tube 2 is fixedly connected to the outer tube 1, and an eccentric portion is located on the right side of the eccentric tube 2. The axis of the eccentric portion of the eccentric tube 2 is below the axis of the outer tube 1. The outer tube 1 has an exhaust port located above the eccentric tube 2. The left side of the eccentric tube 2 is connected to an oil extraction device via a first pipe. Oil in the eccentric tube 2 is pumped to the ground by the oil extraction device. Simultaneously, a second pipe is sleeved outside the first pipe on the left side of the eccentric tube 2. Gas in the outer tube 1 enters the space between the first and second pipes through the exhaust port on the second pipe and is discharged to the ground. Liquid inlets 201 with equal spacing and different heights are provided on the lower side of the eccentric portion of the eccentric tube 2. The following example illustrates one distribution of the liquid inlets 201 to help those skilled in the art understand the working process of this eccentric inhaler. The distribution of the liquid inlets 201 is as follows: a lower row of liquid inlets 201, two rows of liquid inlets 201 at medium height, and two rows of liquid inlets 201 at higher height (the medium and higher heights are only used for...). Compared with the one below (not limited to the position of the inlet hole 201 corresponding to the eccentric tube 2), two arc-shaped baffles 3 are slidably connected inside the eccentric tube 2, and both arc-shaped baffles 3 are used to block the inlet holes 201. In the initial state, the two arc-shaped baffles 3 block the two rows of inlet holes 201 at the higher height. Two limiting semi-rings 4 are fixed inside the eccentric tube 2, which are symmetrically distributed and jointly used to limit the two arc-shaped baffles 3. A sliding frame 5 is slidably connected to the upper side of the eccentric tube 2. The sliding frame 5 is composed of... The sliding frame 5 consists of a vertical rod and an arc-shaped rod. The two ends of the arc-shaped rod of the sliding frame 5 are respectively fixed with floats 6 located on the front and rear sides of the eccentric tube 2. The lower end of the vertical rod of the sliding frame 5 is fixed with an I-shaped frame 7 located inside the eccentric tube 2. The I-shaped frame 7 is provided with two rectangular through slots distributed on the left and right. Sliding plates 8 are symmetrically distributed on the front and back and hinged to the adjacent arc-shaped baffles 3 in the rectangular through slots of the I-shaped frame 7. The floats 6 are higher than the lowest side of the arc-shaped baffles 3, ensuring that the lowest side of the arc-shaped baffles 3 is always below the oil liquid surface.

[0028] This eccentric suction device synchronously changes the number of connected inlet holes 201 based on changes in the liquid level within the horizontal well. This not only maximizes the oil extraction rate but also reduces the amount of gas entering the eccentric tube 2. The specific operation is as follows: Figure 5 The illustrated state represents a horizontal well with a moderate oil content. At this point, the two rows of inlet holes 201 at higher elevations are blocked by two arc-shaped baffles 3. Oil can only enter the eccentric tube 2 through the lower row of inlet holes 201 and the two rows of inlet holes 201 at medium elevations. When the oil level in the horizontal well rises (gas content decreases), the two floats 6 rise with the oil level. The two floats 6, through the sliding frame 5, drive the I-beam frame 7 upwards. The I-beam frame 7 then drives the four sliding plates 8 upwards, and the four sliding plates 8 drive the two arc-shaped baffles upwards. At this point... Figure 5Described from the front view, the left arc-shaped baffle 3 rotates clockwise around its axis under the guidance of the two limiting semi-rings 4, while the right arc-shaped baffle 3 rotates counterclockwise around its axis. The right arc-shaped baffle 3 drives the right sliding plate 8 to move to the left, and the two sliding plates 8 move closer to each other. Finally, the two arc-shaped baffles 3 no longer block the two rows of inlet holes 201 at the higher height. Oil in the horizontal well enters the eccentric tube 2 through the two rows of inlet holes 201 at the higher height, increasing the oil intake. When the oil level drops (due to higher gas content), the two floats 6 descend with the liquid level, and the two arc-shaped baffles 3 block the two rows of inlet holes 201 at the middle height. At this time, only the lower row of inlet holes 201 allows oil to enter, thereby reducing the amount of gas entering the eccentric tube 2. During the change of oil level, the floats 6 are always higher than the bottom of the arc-shaped baffle 3, ensuring that the bottom of the arc-shaped baffle 3 is always below the liquid level, thereby reducing the amount of gas entering the eccentric tube 2. Example 2

[0029] Based on Example 1, an eccentric suction device for horizontal wells, such as... Figures 1-7 As shown, an intercepting net for intercepting sand in oil is provided inside the inlet hole 201. A sleeve 9 is fixedly connected to the right side of the eccentric tube 2. A first sliding tube 10 is slidably connected to the right side of the sleeve 9. A sealing ring 11 is fixedly connected to the first sliding tube 10 and slidably connected to the inside of the sleeve 9. A first tension spring 12 is fixedly connected between the sealing ring 11 and the sleeve 9. A through hole 901 is provided on the upper part of the right side of the sleeve 9. A first U-shaped plate 13 is fixedly connected to the right side of the first sliding tube 10. Two sliding members 14 are symmetrically distributed on the left side of the first U-shaped plate 13 (in this embodiment, the connection between the two sliding members 14 and the first U-shaped plate 13 is considered as fixed). A scraper 15 is fixedly connected to the lower end of the two sliding members 14. An inner arc-shaped surface coaxial with the eccentric part of the eccentric tube 2 is provided on the upper side of the scraper 15. In this embodiment, the inner arc-shaped surface of the scraper 15 is in contact with the outer side of the eccentric tube 2. The scraper 15 is used to scrape off the sand outside the inlet hole 201.

[0030] The oil pumping process is divided into an upstroke and a downstroke. During the upstroke, oil enters the eccentric tube 2 through the inlet hole 201. During the downstroke, oil stops entering the eccentric tube 2. During the process of oil entering the eccentric tube 2 through the inlet hole 201, sand carried in the oil is intercepted by the filter screen of the inlet hole 201. However, some sand is adsorbed on the outside of the inlet hole 201. Therefore, it is necessary to remove the adsorbed sand from the outside of the inlet hole 201. The specific operation is as follows: Initially, the inner arc-shaped surface of the scraper 15 contacts the lower side of the eccentric part of the eccentric tube 2. During the upstroke, the pressure inside the eccentric tube 2 decreases, causing the sealing ring 11 to move to the left. The first tension spring 12 is stretched, and the pressure on the right side of the sealing ring 11 decreases, allowing oil or gas in the horizontal well to enter the sleeve 9 through the through hole 901 and then into the sealing ring 11. On the right side, the sealing ring 11 drives the scraper 15 to move to the left through the first slide tube 10, the first U-shaped plate 13 and the two sliding parts 14. The scraper 15 moves to the left close to the outside of the eccentric part of the eccentric tube 2. The scraper 15 scrapes away the sand adsorbed on the outside of the inlet hole 201, thereby increasing the oil intake of the inlet hole 201 and improving the oil pumping efficiency. During the downstroke, the pressure inside the eccentric tube 2 decreases, and the tension of the first tension spring 12 is released, which drives the sealing ring 11 to move to the right. The gas or oil on the right side of the sealing ring 11 inside the sleeve 9 is discharged into the horizontal well through the through hole 901. At the same time, the scraper 15 moves to the right again to scrape away the sand adsorbed on the outside of the inlet hole 201. When the tension of the first tension spring 12 is restored, the scraper 15 is located on the right side of the inlet hole 201. The above steps are repeated as the oil pumping process continues. Example 3

[0031] Based on Example 2, an eccentric suction device for horizontal wells, such as... Figures 1-7As shown, the first slide tube 10 is slidably connected to a second slide tube 16, which is slidably connected to a sealing ring 11. A second U-shaped plate 17 is fixedly connected to the right side of the second slide tube 16. The second U-shaped plate 17 is located above the first U-shaped plate 13. Two springs symmetrically distributed front and rear are fixedly connected between the first U-shaped plate 13 and the scraper 15. An inclined portion is provided on the upper side of the sliding member 14. The second U-shaped plate 17 is used to press the inclined portions of the symmetrically distributed sliding members 14. The second U-shaped plate 17 moves to the left to press the inclined portions of the two sliding members 14, causing the two sliding members 14 to move upward. Both sliding members 14 are slidably connected to the first U-shaped plate 13. A sleeve 9 is fixedly connected to the left side of the second slide tube 16. The piston 18 is connected to the inner sealing sliding connection. The piston 18 is located to the left of the sealing ring 11. A second tension spring 19 is fixed between the piston 18 and the sealing ring 11. The second slide tube 16 is connected to the cavity between the inner sealing ring 11 and the piston 18 of the sleeve 9. The inner diameter of the second slide tube 16 is larger than the diameter of the through hole 901. The scraper 15 has an outer arc-shaped surface coaxial with the outer tube 1 on its lower side. In the initial state, the outer arc-shaped surface of the scraper 15 is in contact with the lower side of the inner wall of the outer tube 1. The longitudinal length of the middle part of the scraper 15 is less than the distance between the lowest side of the eccentric part of the eccentric tube 2 and the lowest side of the inner wall of the liquid inlet of the outer tube 1. In the initial state, the inner arc-shaped surface of the scraper 15 is not in contact with the outer side of the eccentric part of the eccentric tube 2.

[0032] Due to the special structural design of the eccentric suction device, the space between the eccentric part of the eccentric tube 2 and the lower side of the inner wall of the inlet of the outer tube 1 is small. As the oil extraction process proceeds, sand continuously enters this space and accumulates below the inlet hole 201. With the accumulation of sand, the inlet hole 201 will be blocked from bottom to top, thereby significantly reducing the amount of oil extracted and affecting the oil extraction efficiency. In this embodiment, the sand below the eccentric part of the eccentric tube 2 is pushed to the outside of the outer tube 1, thereby reducing the accumulation of sand below the eccentric part of the eccentric tube 2 and facilitating oil extraction. The specific operation is as follows:

[0033] In the initial state, such as Figure 3As shown, the lower side of the scraper 15 contacts the lower side of the inner wall of the inlet of the outer tube 1. During the upstroke, the pressure inside the eccentric tube 2 decreases, and the pressure on the left side of the piston 18 inside the sleeve 9 decreases, causing the piston 18 to move to the left. The second tension spring 19 is stretched, and the piston 18 moves to the left, drawing oil or gas from the horizontal well into the space between the sealing ring 11 and the piston 18 through the second slide tube 16. The piston 18 drives the second slide tube 16 to move to the left. During the leftward movement of the piston 18, the piston 18 drives the sealing ring 11 to move to the left through the second tension spring 19. The first tension spring 12 is stretched, and the sealing ring 11 drives the first slide tube 10 to move to the left. Oil or gas in the well enters the right side of the inner sealing ring 11 of the sleeve 9 through the through hole 901. Since the inner diameter of the second slide tube 16 is larger than the diameter of the through hole 901, the speed at which oil and gas flow through the second slide tube 16 in the horizontal well is greater than the speed at which they flow through the through hole 901. The speed at which the piston 18 moves to the left is greater than the speed at which the sealing ring 11 moves to the left. The piston 18 moves to the left relative to the sealing ring 11. The movement of the second slide tube 16 to the left compresses the inclined portions of the two sliding members 14 through the second U-shaped plate 17, causing the two sliding members 14 to move upward. The two sliding members 14 drive the scraper 15 to move upward, and the spring on the scraper 15 is compressed.

[0034] When the inner arc surface of scraper 15 contacts the eccentric tube 2, scraper 15 no longer moves upward, and piston 18 no longer moves to the left relative to sealing ring 11. Instead, piston 18 and sealing ring 11 move to the left synchronously. Sealing ring 11 drives scraper 15 to move to the left through first slide tube 10, first U-shaped plate 13 and two sliding parts 14. The outer arc surface of scraper 15 does not contact the lower side of the inner wall of the liquid inlet of outer tube 1. Therefore, scraper 15 will not push the sand below the eccentric part of eccentric tube 2 to the left. During the process of scraper 15 moving to the left, scraper 15 scrapes off the sand outside of liquid inlet 201. The scraped sand accumulates below liquid inlet 201. When scraper 15 is on the left side of liquid inlet 201, piston 18 is on the left side inside sleeve 9 and no longer moves to the left (the diameter of the left side inside sleeve 9 is smaller than the diameter of the middle part, which limits piston 18).

[0035] During the downstroke, the pressure inside the eccentric tube 2 decreases. At this time, the tension of the first tension spring 12 and the second tension spring 19 is released simultaneously. Since the inner diameter of the second slide tube 16 is larger than the diameter of the through hole 901, the piston 18 moves to the right at a speed greater than the sealing ring 11 moves to the right. The piston 18 moves to the right relative to the sealing ring 11. The piston 18 drives the second U-shaped plate 17 to move to the right through the second slide tube 16. The second U-shaped plate 17 no longer presses against the inclined parts of the two sliding members 14. The elastic force of the two springs on the scraper 15 is released, causing the scraper to move to the right. Plate 15 and two sliding members 14 move downwards. When the tension of the second tension spring 19 is restored, the outer arc surface of scraper 15 fits against the lower side of the inner wall of the liquid inlet of outer tube 1. Subsequently, sealing ring 11 and piston 18 move to the right in sync. Scraper 15 moves to the right and pushes the sand below the eccentric part of eccentric tube 2 to the right. When the first tension spring 12 is reset, scraper 15 pushes the sand below the eccentric part of eccentric tube 2 out of the liquid inlet of outer tube 1, thereby reducing the amount of sand below liquid inlet hole 201 and improving oil extraction efficiency. The above steps are repeated as the oil extraction process proceeds.

[0036] The present application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present application. Therefore, the content of this specification should not be construed as a limitation of the present application.

Claims

1. An eccentric suction device for a horizontal well, comprising an outer tube (1) having a liquid inlet, an eccentric tube (2) fixedly connected to the outer tube (1), an eccentric portion being provided on the side of the eccentric tube (2) near the liquid inlet of the outer tube (1), the axis of the eccentric portion of the eccentric tube (2) being located below the axis of the outer tube (1), an exhaust port being provided on the outer tube (1) above the eccentric tube (2), and liquid inlets (201) being provided at equal intervals and at different heights on the lower side of the eccentric portion of the eccentric tube (2), characterized in that, The eccentric tube (2) is slidably connected with symmetrically distributed arc-shaped baffles (3), and the symmetrically distributed arc-shaped baffles (3) are all used to block the liquid inlet hole (201). The eccentric tube (2) is fixed with symmetrically distributed limiting semi-rings (4) that are used to limit the symmetrically distributed arc-shaped baffles (3). The eccentric tube (2) is slidably connected to a sliding frame (5), the sliding frame (5) is fixedly connected to symmetrically distributed floats (6) located outside the eccentric tube (2), the sliding frame (5) is fixedly connected to an I-shaped frame (7) located inside the eccentric tube (2), and the I-shaped frame (7) is slidably connected to symmetrically distributed sliding plates (8) that are respectively hinged to the adjacent arc-shaped baffles (3).

2. An eccentric suction device for horizontal wells according to claim 1, characterized in that, The float (6) is higher than the lowest part of the arc-shaped baffle (3).

3. An eccentric suction device for horizontal wells according to claim 1, characterized in that, The inlet hole (201) is equipped with an interception net for intercepting sand in oil.

4. An eccentric suction device for a horizontal well according to claim 3, characterized in that, The eccentric tube (2) is fixedly connected to a sleeve (9), and the sleeve (9) is slidably connected to a first slide tube (10). The first slide tube (10) is fixedly connected to a sealing ring (11) that is slidably connected to the inside of the sleeve (9). A first tension spring (12) is fixedly connected between the sealing ring (11) and the sleeve (9). The sleeve (9) is provided with a through hole (901). The first slide tube (10) is fixedly connected to a first U-shaped plate (13). The first U-shaped plate (13) is provided with symmetrically distributed sliding parts (14). The symmetrically distributed sliding parts (14) are all fixedly connected to a scraper (15). The scraper (15) is provided with an inner arc-shaped surface coaxial with the eccentric part of the eccentric tube (2). The scraper (15) is used to scrape off the sand outside the liquid inlet (201).

5. An eccentric suction device for a horizontal well according to claim 4, characterized in that, The first slide tube (10) is sealed and slidably connected to the second slide tube (16) which is sealed and slidably connected to the sealing ring (11). The second slide tube (16) is fixedly connected to the second U-shaped plate (17). The first U-shaped plate (13) is fixedly connected to the scraper (15) with a spring. The sliding member (14) is provided with an inclined portion. The second U-shaped plate (17) is used to squeeze the inclined portion of the symmetrically distributed sliding member (14). The symmetrically distributed sliding members (14) are all slidably connected to the first U-shaped plate (13). The second slide tube (16) is fixedly connected to the piston (18) which is sealed and slidably connected to the sleeve (9). The piston (18) is fixedly connected to the sealing ring (11) with a second tension spring (19). The second slide tube (16) communicates with the cavity between the sealing ring (11) and the piston (18) in the sleeve (9).

6. An eccentric suction device for a horizontal well according to claim 5, characterized in that, The inner diameter of the second slide tube (16) is larger than the diameter of the through hole (901).

7. An eccentric suction device for a horizontal well according to claim 5, characterized in that, The scraper (15) is provided with an outer arc-shaped surface coaxial with the outer tube (1).

8. An eccentric suction device for a horizontal well according to claim 7, characterized in that, The longitudinal length of the middle part of the scraper (15) is less than the distance between the lowest side of the eccentric part of the eccentric tube (2) and the lowest side of the inner wall of the inlet of the outer tube (1).

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