Device and method for adjusting throttler through underground robot

Abstract

The invention discloses a device for adjusting a throttler through an underground robot. The device comprises a well mouth control unit, the underground robot and the adjustable throttler. The well mouth control unit is in communication connection with the underground robot, the well mouth control unit can control the underground robot to move up and down in a shaft, and the adjustable throttling device is connected with the underground robot to adjust the size of the air tap. The invention further discloses a method for adjusting the throttler through the underground robot. Gravity and upward thrust of airflow during gas well production are fully utilized, and ascending and descending of the underground robot in an oil pipe are achieved through expansion and contraction of the rubber sleeve. When the diameter of the current air tap cannot meet the production requirement along with the reduction of the production pressure of the gas well, the underground robot descends to be combined with the adjustable throttling device to complete the adjustment of the size of the air tap, so that the construction period is effectively shortened, and the operation efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of natural gas extraction equipment, relates to a device for adjusting a choke by using a downhole robot, and also relates to a method for adjusting a choke by using a downhole robot. Background Art

[0002] In order to reduce pressure, throttle, limit production and adjust production in natural gas extraction, downhole chokes are often installed in the wellbore of the gas well. Downhole chokes are divided into slip chokes and preset chokes according to different seating methods. The slip choke is placed through the well test wire operation, and the seat is anchored at any position in the production string to throttle production; when the gas well is adjusted or no throttling is required, the choke is salvaged by connecting the salvage tool through the well test wire operation. The preset choke is placed through the well test wire operation, and the seat is anchored in the preset working cylinder (the preset working cylinder is connected to the production string and lowered into the well with the production string); when the gas well is adjusted or no throttling is required, the GS salvage tool is connected through the well test wire operation to salvage the choke core. The success rates of salvaging the slip-type choke and the preset choke are 67% and 75% respectively, which are not high. In addition, when the salvage of these two types of chokes fails, it affects the production adjustment of gas wells, the smooth implementation of the mid-term drainage and gas production process, and the later production needs such as lifting the pipe under pressure.

[0003] Existing data research shows that the only intelligent downhole chokes currently available (such as the Chinese patent "An adjustable intelligent downhole throttle valve for gas wells", publication number CN213016307U; the Chinese patent "An intelligent downhole throttle valve for emergency shutdown of gas wells", publication number CN206338053U; the Chinese patent "An intelligent downhole throttle device", publication number CN209398399U; the Chinese patent "An intelligent throttle for natural gas wells", publication number CN108343404B; the Chinese patent "An intelligent downhole throttle suitable for oil and gas field production", publication number C N215332773U) have integrated mechatronics into the downhole throttle, but downhole batteries, downhole storage batteries, electronic components, etc. have poor stability and high cost in the downhole, which affect the downhole adjustment of the downhole throttle; at the same time, the throttle nozzle in these designs is automatically adjusted according to the bottom hole pressure fluctuation, which is easily affected by temporary pressure fluctuations in the well, or the pressure changes caused by sudden conditions in some gas wells, which may cause the throttle nozzle to operate frequently or operate incorrectly; it is also possible that the pressure wave command signal is distorted when it is transmitted to the downhole, affecting the receiving efficiency, thereby affecting the adjustment of the nozzle. Summary of the invention

[0004] The purpose of the present invention is to provide a device for adjusting a choke by using a downhole robot, wherein the downhole robot can reciprocate up and down in the well to complete the choke adjustment.

[0005] Another object of the present invention is to provide a method for adjusting a choke using a downhole robot.

[0006] The technical solution adopted by the present invention is to use a device for adjusting the throttle by a downhole robot, including a wellhead control unit, a downhole robot and an adjustable throttle; the wellhead control unit and the downhole robot are communicatively connected, and the wellhead control unit can control the downhole robot to move up and down in the wellbore, and the adjustable throttle is connected to the downhole robot to complete the adjustment of the air nozzle size.

[0007] The present invention is also characterized in that:

[0008] The downhole robot includes a first salvage neck, in which a T-shaped pressure-taking channel is arranged; a straightening ring is welded on the outer periphery of the first salvage neck; a pressure sensor is also arranged inside the first salvage neck; a second pressure sensor is located at the lower part of the pressure-taking channel; the second pressure sensor is connected to the upper end of the communication and control module, and the lower end of the communication and control module is electrically connected to the upper end of the reduction motor; it also includes an adjusting core rod, and the lower end of the reduction motor is inserted into the square hole connected to the upper end of the adjusting core rod; the cross shaft at the upper end of the adjusting core rod is provided with plane bearings at both axial ends; a fixing piece is sleeved on the outer wall of the adjusting core rod, the upper end of the fixing piece compacts the lower end of the plane bearing, and the lower end is threadedly connected to the docking hexagonal piece; a rubber tube is sleeved on the outer wall of the fixing piece, and the upper end of the rubber tube is threadedly connected to the lower end of the first salvage neck; the lower end of the adjusting core rod is threadedly connected to the external adjusting hexagonal piece.

[0009] A sealing ring is also arranged between the plane bearing and the axial ends of the cross shaft of the adjusting core rod.

[0010] The adjustable flow device comprises a second salvage neck, a docking inner hexagonal piece, an adjusting inner hexagonal piece, a fixing clamp ring, a spring sheet, a clamp block, a rubber tube support block, a sealing rubber tube, an inner adjusting piece, an adjusting thread, an inner ceramic ring, an outer slotted throttling ring, and a sand cover. The second salvage neck is provided with a concave step matching the docking hexagonal piece and the adjusting hexagonal piece. An outer tube is sleeved on the middle part of the outer wall of the second salvage neck, a clamp block is symmetrically arranged in the through hole at the lower end of the outer tube, and the fixing clamp ring is placed in a ring formed by the threaded section of the outer wall of the second salvage neck and the groove of the inner wall of the outer tube. A rubber tube support block is sleeved on the outer wall of the upper end of the inner adjusting piece, the rubber tube support block is threadedly connected to the inner adjusting piece, the upper end of the rubber tube support block is threadedly connected to the lower end of the second salvage neck, and the inner ceramic ring is glued to the lower end of the outer wall of the inner adjusting piece. The sealing rubber tube is sleeved on the outer wall of the upper end of the rubber tube support block.

[0011] The sand-proof cover is threadedly connected with the rubber tube support block, and the outer wall of the sand-proof cover is provided with a plurality of radial slits.

[0012] An outer slotted throttling ring is sleeved on the outer wall of the inner ceramic ring, and the middle and lower part of the rubber cylinder supporting block is sleeved on the inner ceramic ring and the outer wall of the outer slotted throttling ring.

[0013] Another technical solution adopted by the present invention is a method for adjusting a choke by using an underground robot, specifically:

[0014] S1: In the working state, the adjustable throttle is installed under the wellbore of the gas well and fixed by the clamp block, the rubber tube expands to separate the wellbore, and the high-pressure gas produced by the gas well flows into the wellbore and passes through the throttle formed by the inner adjustment part and the inner ceramic ring of the adjustable throttle. Due to the throttling effect, the wellbore pressure above the adjustable throttle drops to medium and low pressure. At this time, the gas flow rate increases, and the high-speed airflow carries the droplets up to the wellhead and then outputs them to the downstream unit, completing the normal throttling and pressure reduction production;

[0015] S2: During the production of a gas well, when the size of the throttle formed by the inner adjusting piece and the inner ceramic ring of the adjustable throttle cannot meet the production needs of the gas well, the second fishing neck connected to the hexagonal piece is adjusted, and the reduction motor rotates. The reduction motor drives the adjusting core rod and the adjusting hexagonal piece to rotate in turn, thereby driving the inner adjusting piece of the adjustable throttle to rotate, changing the size of the throttle formed by the inner adjusting piece and the inner ceramic ring to achieve the required gas well production.

[0016] The beneficial effects of the present invention are:

[0017] The present invention makes full use of gravity and the upward thrust of the airflow during gas well production, and realizes the up and down movement of the downhole robot in the oil pipe through the expansion and contraction of the rubber cylinder. As the production pressure of the gas well decreases, when the current nozzle diameter cannot meet the production demand, the downhole robot is combined with the adjustable flow device to complete the adjustment of the nozzle size, effectively shortening the construction period, improving the operation efficiency, and reducing the cost. It not only saves manpower, material resources, time and other costs, but also protects the ecological environment, which is in line with the concept of "reducing costs and increasing efficiency". BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of a device for adjusting a choke by using a downhole robot in the present invention;

[0019] Figure 2 It is a structural diagram of a wellhead control unit in a device for adjusting a choke by using a downhole robot according to the present invention;

[0020] Figure 3 It is a structural diagram of the downhole robot in the device for adjusting the choke by using the downhole robot of the present invention;

[0021] Figure 4 It is a structural diagram of an adjustable choke in a device for adjusting a choke by using a downhole robot according to the present invention;

[0022] Figure 5 The present invention utilizes a remote control working state diagram of a device for adjusting a throttle by a downhole robot.

[0023] In the figure, 1. wellhead control unit, 2. downhole robot, 3. adjustable flow device, 4. blowout preventer, 5. communication and charging device, 6. electric capture device, 7. regulating valve, 8. flow meter, 9. first pressure sensor, 10. first fishing neck, 11. pressure sampling channel, 12. second pressure sensor, 13. straightening ring, 14. communication and control module, 15. high temperature battery, 16. control circuit board, 17. temperature sensor, 18. reduction motor, 19. flat Surface bearing, 20. Sealing ring, 21. Adjusting core rod, 22. Rubber cylinder, 23. External fixing part, 24. Docking hexagonal piece, 25. Adjusting hexagonal piece, 26. Second salvage neck, 27. Docking inner hexagonal piece, 28. Adjusting inner hexagonal piece, 29. Fixing clamp ring, 30. Spring sheet, 31. Clamp block, 32. Rubber cylinder support block, 33. Sealing rubber cylinder, 34. Internal adjusting part, 35. Adjusting thread, 36. Internal ceramic ring, 37. External slit throttling ring, 38. Sand cover. DETAILED DESCRIPTION

[0024] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1

[0026] The present invention utilizes a device for adjusting a choke by a downhole robot, such as Figure 1 As shown, it includes a wellhead control unit 1, a downhole robot 2 and an adjustable flow device 3;

[0027] The wellhead control unit 1 is connected to the downhole robot 2 for communication, and can send instructions and charge the downhole robot 2. At the same time, it can read the operating pressure, temperature, gravity acceleration and other data of the downhole robot 2 and send them to the remote end. The downhole robot 2 can move up and down in the wellbore, and can be used in combination with the wellhead control unit 1, or it can be used alone to complete the adjustment of the adjustable flow device 3. The adjustable flow device 3 is designed with a nozzle adjustment mechanism inside, which only has mechanical parts, ensuring the reliability of the device. The downhole robot 2 can go down to the adjustable flow device 3, dock with it, complete the nozzle adjustment, and realize the production of gas wells with different gas production rates.

[0028] Example 2

[0029] like Figure 2As shown, the wellhead control unit 1 includes a lubricating preventer 4, a communication and charging device 5, an electric capture device 6, a regulating valve 7, a flow meter 8 and a first pressure sensor 9. The communication and charging device 5, the electric capture device 6, the regulating valve 7, the flow meter 8 and the first pressure sensor 9 are connected by cables, and the lubricating preventer 4 is connected to the wellhead to buffer the impact force of the downhole robot reaching the wellhead. When the downhole robot 2 needs to be charged, the electric capture device 6 moves, and the downhole robot 2 remains at the wellhead, and communicates and charges through the communication and charging device 5. The second pressure sensor 12 and the temperature sensor 17 in the downhole robot 2 can be linked with the regulating valve 7, the flow meter 8 and the first pressure sensor 9 through intelligent control to control the up and down speeds of the downhole robot 2.

[0030] like Figure 3 As shown, the downhole robot 2 includes a first salvage neck 10, in which a T-shaped pressure channel 11 is arranged; a straightening ring 13 is welded on the outer periphery of the first salvage neck 10; a pressure sensor 12 is also arranged inside the first salvage neck 10; the second pressure sensor 12 is located at the lower part of the pressure channel 11; the second pressure sensor 12 is connected to the upper end of the communication and control module 14 by a convenient connector, and the lower end of the communication and control module 14 is electrically connected to the upper end of the reduction motor 18 by a convenient connector; the communication and control module 14 includes an electrically connected high-temperature battery 15, a control circuit board 16, and a temperature sensor 17;

[0031] It also includes an adjusting core rod 21, the lower end of the reduction motor 18 is inserted into the square hole connected to the upper end of the adjusting core rod 21; both axial ends of the cross shaft at the upper end of the adjusting core rod 21 are provided with plane bearings 19; a sealing ring 20 is also provided between the plane bearing 19 and the axial ends of the cross shaft of the adjusting core rod 21; a fixing piece 23 is sleeved on the outer wall of the adjusting core rod 21, the upper end of the fixing piece 23 presses the lower end of the plane bearing 19, and the lower end is threadedly connected to the docking hexagonal piece 24; a rubber sleeve 22 is sleeved on the outer wall of the fixing piece 23, and the upper end of the rubber sleeve 22 is threadedly connected to the lower end of the first salvage neck 10; the lower end of the adjusting core rod 21 is threadedly connected to the outer adjusting hexagonal piece 25;

[0032] The rubber sleeve 22 is used to seal the pipe wall to enable the downhole robot 2 to move up or down in the wellbore. The external fixing piece 23, the docking hexagonal piece 24, and the adjusting hexagonal piece 25 are used to achieve docking with the adjustable flow device 3.

[0033] like Figure 4As shown, the adjustable flow device 3 includes a second fishing neck 26, a docking hexagonal piece 27, an adjusting hexagonal piece 28, a fixing clamp 29, a spring sheet 30, a clamp block 31, a rubber tube support block 32, a sealing rubber tube 33, an inner adjusting piece 34, an adjusting thread 35, an inner ceramic ring 36, an outer slit throttling ring 37, and a sand control cover 38. The second salvage neck 26 has a concave step inside that matches the docking hexagonal piece 24 and the adjusting hexagonal piece 25; the outer tube 28 is sleeved in the middle of the outer wall of the second salvage neck 26 and locked by a pin; a clamp block 31 is symmetrically arranged in the through hole at the lower end of the outer tube 28, and the clamp block 31 is embedded in the outer tube 28 by a spring sheet 30; the fixed clamp ring 29 is placed in the ring formed by the threaded section of the outer wall of the salvage neck 26 and the groove of the inner wall of the outer tube 28; an inner ceramic ring 36 is glued to the lower end of the outer wall of the inner adjusting piece 34, and a boss adjusting thread is provided in the middle and lower part of the outer wall of the inner adjusting piece 34; an outer slit throttling ring 37 is sleeved on the outer wall of the inner ceramic ring 36, and the lower end is inserted into the groove of the lock cover;

[0034] A rubber cylinder support block 32 is sleeved on the outer wall of the upper end of the inner adjusting member 34, and the rubber cylinder support block 32 is threadedly connected to the inner adjusting member 34. The upper end of the rubber cylinder support block 32 is threadedly connected to the lower end of the second salvage neck 26. The lower and middle part of the rubber cylinder support block 32 is sleeved on the outer wall of the inner ceramic ring 36 and the outer slit throttle ring 37, and is threadedly connected to the lock cover; the sealing rubber cylinder 33 is sleeved on the outer wall of the upper end of the rubber cylinder support block 32; the sand cover 38 is threadedly connected to the rubber cylinder support block 32, and the outer wall of the sand cover 38 has a plurality of radial slits.

[0035] The docking hexagonal piece 24 and the adjusting hexagonal piece 25 in the downhole robot 2 are matched and connected with the second fishing neck 26 in the adjustable flow device 3 .

[0036] Example 3

[0037] The method for adjusting the choke by using the downhole robot of the present invention is specifically as follows:

[0038] S1: In the working state, the adjustable throttle 3 is installed at a certain position (depth>1000m) under the wellbore of the gas well and is fixed by the clamp block 31, and the rubber tube 32 expands to separate the wellbore. After the high-pressure gas (≥20MPa) produced by the gas well flows into the wellbore and passes through the throttle formed by the inner adjustment part 34 and the inner ceramic ring 36 of the adjustable throttle 3, the wellbore pressure above the adjustable throttle 3 drops to a medium-low pressure (<6.4MPa) due to the throttling effect. At this time, the gas flow rate increases, and the high-speed airflow carries the droplets up to the wellhead and then transports them to the downstream unit to complete the normal throttling and pressure reduction production.

[0039] S2: During the gas well production process, when the size of the throttle formed by the inner adjusting piece 34 and the inner ceramic ring 36 of the adjustable throttle 3 cannot meet the production needs of the gas well, the fishing neck 26 connected to the docking hexagonal piece 24 is adjusted, and the reduction motor 18 rotates. The reduction motor 18 drives the adjusting core rod 21 and the adjusting hexagonal piece 25 to rotate in turn. The adjusting hexagonal piece 25 rotates with the help of the reduction motor 18 to drive the inner adjusting piece 34 of the adjustable throttle 3 to rotate, change the size of the throttle formed by the inner adjusting piece 34 and the inner ceramic ring 36, and complete the required gas well production.

[0040] The downhole adjustable throttle of the present invention only retains the mechanical structure, and the adjustment is achieved through the downhole robot, which avoids the long-term instability of electronic components in the well; the downhole robot can be combined with the throttle, and the communication and adjustment are controlled through the wellhead. If there is no electricity, the downhole robot goes up to the wellhead to charge; at the same time, the uphole and downhole can communicate through pressure waves. The present invention makes full use of gravity and the upward thrust of the airflow during gas well production, and combines the closed pipeline of the downhole robot to realize the up and down movement of the downhole robot; the present invention can establish communication with the remote end through the wellhead control device, and can realize remote downhole throttle adjustment.

[0041] Example 4

[0042] like Figure 5 As shown, it is a schematic diagram of the remote control working state of the present invention. Under normal working conditions, the downhole robot 2 is always located underground, and can communicate with the wellhead through pressure wave changes. The wellhead generates pressure fluctuations through the regulating valve 7, thereby achieving the purpose of remotely regulating the gas well production. When the power of the downhole robot 2 is low, according to the built-in program of the control circuit board 16, the downhole robot 2 pushes the regulating core rod 21 through the reduction motor 18 to make the rubber cylinder 22 seal the pipe wall, and the downhole robot 2 goes up to the wellhead. At the wellhead, by prompting the electric capture device 6 to operate, the downhole robot 2 is at the wellhead position, and is charged through the communication and charging device 5.

[0043] The present invention can place the downhole robot 2 on the downhole adjustable flow device 3 for a long time, so as to achieve the purpose of remote control in time. The downhole robot 2 can also be placed in the wellhead state at ordinary times, and only when adjustment is needed, the wellhead communication sends a command, and the downhole robot 2 goes down to complete the adjustment, and then goes up to wait at the wellhead after the adjustment.

Claims

1. A device for adjusting a choke using an underground robot, characterized in that: The invention comprises a wellhead control unit (1), a downhole robot (2) and an adjustable flow device (3); the wellhead control unit (1) and the downhole robot (2) are communicatively connected, and the wellhead control unit (1) can control the downhole robot (2) to move up and down in the wellbore; the adjustable flow device (3) is connected to the downhole robot (2) to complete the adjustment of the size of the gas nozzle.

2. The device for adjusting a choke using a downhole robot according to claim 1, characterized in that: The downhole robot (2) comprises a first fishing neck (10), wherein a T-shaped pressure channel (11) is arranged inside the first fishing neck (10); a straightening ring (13) is welded on the outer periphery of the first fishing neck (10); a pressure sensor (12) is also arranged inside the first fishing neck (10); the second pressure sensor (12) is located at the lower part of the pressure channel (11); the second pressure sensor (12) is connected to the upper end of the communication and control module (14), and the lower end of the communication and control module (14) is electrically connected to the upper end of the reduction motor (18); and the robot also comprises an adjusting core rod (21), the reduction The lower end of the speed motor (18) is inserted into the square hole at the upper end of the connecting and adjusting core rod (21); the cross shaft at the upper end of the adjusting core rod (21) is provided with plane bearings (19) at both ends of the axial direction; the outer wall of the adjusting core rod (21) is sleeved with a fixing piece (23), the upper end of the fixing piece (23) presses the lower end of the plane bearing (19), and the lower end is threadedly connected to the docking hexagonal piece (24); the outer wall of the fixing piece (23) is sleeved with a rubber sleeve (22), the upper end of the rubber sleeve (22) is threadedly connected to the lower end of the first fishing neck (10); the lower end of the adjusting core rod (21) is threadedly connected to the outer adjusting hexagonal piece (25).

3. The device for adjusting a choke using a downhole robot according to claim 2, characterized in that: A sealing ring (20) is also provided between the plane bearing (19) and the axial ends of the cross shaft of the adjusting core rod (21).

4. The device for adjusting a choke using a downhole robot according to claim 2, characterized in that: The adjustable flow device (3) comprises a second fishing neck (26), a docking inner hexagonal piece (27), an adjusting inner hexagonal piece (28), a fixing clamp (29), a spring sheet (30), a clamp block (31), a rubber tube support block (32), a sealing rubber tube (33), an inner adjusting piece (34), an adjusting thread (35), an inner ceramic ring (36), an outer slotted throttling ring (37), and a sand cover (38). The second fishing neck (26) has a concave step inside that matches the docking inner hexagonal piece (24) and the adjusting inner hexagonal piece (25). The outer wall of the second fishing neck (26) is sleeved with an outer tube (28) in the middle. A clamp block (31) is symmetrically arranged in the through hole at the lower end of the outer cylinder (28); the fixed clamp ring (29) is placed in a ring formed by the threaded section of the outer wall of the second fishing neck (26) and the groove of the inner wall of the outer cylinder (28); the outer wall of the upper end of the inner adjustment member (34) is sleeved with a rubber tube support block (32); the rubber tube support block (32) is threadedly connected to the inner adjustment member (34); the upper end of the rubber tube support block (32) is threadedly connected to the lower end of the second fishing neck (26); the lower end of the outer wall of the inner adjustment member (34) is glued with an inner ceramic ring (36); the sealing rubber tube (33) is sleeved on the outer wall of the upper end of the rubber tube support block (32).

5. The device for adjusting a choke using a downhole robot according to claim 4, characterized in that: The sand-proof cover (38) is threadedly connected to the rubber cylinder support block (32), and the outer wall of the sand-proof cover (38) is provided with a plurality of radial slits.

6. The device for adjusting a choke using a downhole robot according to claim 5, characterized in that: An outer slotted throttling ring (37) is sleeved on the outer wall of the inner ceramic ring (36), and the lower middle part of the rubber cylinder support block (32) is sleeved on the outer walls of the inner ceramic ring (36) and the outer slotted throttling ring (37).

7. A method for adjusting a choke using a downhole robot, using the device of claim 6, characterized in that: Specifically: S1: In the working state, the adjustable throttle (3) is installed under the wellbore of the gas well, the rubber tube (32) expands to separate the wellbore, and the high-pressure gas produced by the gas well flows into the wellbore and passes through the throttling nozzle formed by the inner adjustment member (34) and the inner ceramic ring (36). The gas flow rate increases, and the high-speed gas flow carries the liquid droplets up to the wellhead and then is transported to the downstream unit, completing normal throttling and pressure reduction production; S2: During the production process of the gas well, the second fishing neck (26) connected to the butt hexagonal piece (24) is adjusted, the reduction motor (18) rotates, and the reduction motor (18) drives the adjustment core rod (21) and the adjustment hexagonal piece (25) to rotate in turn, thereby driving the internal adjustment piece (34) to rotate, changing the size of the throttle formed by the internal adjustment piece (34) and the internal ceramic ring (36) to achieve the required gas well production.

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