An experimental bench for detecting a downhole drainage gas production pump

Abstract

This invention discloses a test bench for simulating a downhole drainage and gas production pump, comprising a wellbore, a drainage and gas production pump, a water delivery device, and a gas delivery device. The wellbore contains a support ring and a sealing sleeve. A first sealing device and a second sealing device are respectively installed at both ends of the wellbore. The drainage and gas production pump is annularly positioned within the wellbore through the support ring, and the annulus is divided into a low-pressure annulus and a high-pressure annulus by the sealing sleeve. A heating device for heating the high-pressure annulus is installed on the wellbore. One pump inlet of the drainage and gas production pump is located in the high-pressure annulus, and the other pump inlet extends through the first sealing device to the outside of the low-pressure annulus end in the wellbore, and is connected to the inlet of the water delivery device via a pipeline. The outlets of both the water delivery device and the gas delivery device are connected to the high-pressure annulus via pipelines. A detection device is installed on the wellbore. This invention uses a detection device on the wellbore to monitor the gas pressure and fluid inside the high-pressure annulus in real time, providing accurate and effective data support for improving the drainage and gas production process.

Description

Technical Field

[0001] This invention relates to the field of natural gas drainage and gas production technology, specifically to a test bench for simulating downhole drainage and gas production pump testing. Background Technology

[0002] As natural gas wells are extracted during production, the amount of water accumulated downhole increases, forming liquid at the bottom of the well. This reduces the well's liquid-carrying capacity, increases bottomhole pressure loss, and severely reduces gas production. It may even lead to water flooding and production shutdown. In this situation, a mature and complete drainage and gas extraction process is necessary to continue production. Therefore, it is necessary to gradually improve the technology and process through a large number of field tests.

[0003] In the prior art, utility model patent with patent number CN201120502847.1 discloses a wellbore simulation experimental device, which includes: a base, which serves as a support platform for the entire device; a support frame mounted on the base; a hollow cylinder placed on and supported by the support frame, the interior of which can accommodate logging instruments; an upper sealing plug and a lower sealing plug are respectively connected to the two ends of the cylinder, the upper sealing plug having a through-wall sealing structure that can provide online measurement for logging instruments, and the lower sealing plug being connected to a pressure pump, the cylinder together with the interiors of the upper and lower sealing plugs forming a sealed cavity.

[0004] The aforementioned patent provides a device for conducting simulated drainage gas production experiments. This simulation device, through the design of a through-wall sealing structure with an upper sealing plug, enables the online testing function of logging instruments under high temperature and high pressure. However, during the experiment, this device cannot monitor the internal pressure, flow rate, and temperature changes in real time, and therefore cannot provide detailed data for improving the drainage gas production process. Summary of the Invention

[0005] The purpose of this invention is to provide a test bench for simulating downhole drainage and gas production pump testing, which aims to improve the problem that existing devices for simulating drainage and gas production experiments cannot monitor the internal pressure, flow rate, and temperature changes in real time during drainage and gas production experiments, resulting in a lack of detailed data support when improving drainage and gas production processes.

[0006] This invention is implemented as follows: A test bench simulating a downhole drainage and gas production pump includes a wellbore, a drainage and gas production pump, a water delivery device, and a gas delivery device. The wellbore contains a support ring and a sealing sleeve. A first sealing device and a second sealing device are respectively installed at both ends of the wellbore. The drainage and gas production pump is annularly positioned within the wellbore through the support ring, and the annular portion is divided into a low-pressure annulus and a high-pressure annulus by the sealing sleeve. A heating device for heating the high-pressure annulus is installed on the wellbore. One pump outlet of the drainage and gas production pump is located in the high-pressure annulus, and the other pump outlet extends through the first sealing device to the outside of the low-pressure annulus end in the wellbore, and is connected to the inlet of the water delivery device via a pipeline. The outlets of both the water delivery device and the gas delivery device are connected to the high-pressure annulus via pipelines. A testing device is installed on the wellbore.

[0007] Preferably, it also includes a support device, which includes an angle control frame, a hydraulic lifting rod, and a fixed support frame; one end of the fixed support frame is provided with a rotating joint, and the other end is provided with a hydraulic lifting rod; the angle control frame is rotatably positioned above the fixed support frame via the hydraulic lifting rod and the rotating joint; the well shaft is positioned on the angle control frame.

[0008] Preferably, the first sealing device includes a flange, an upper sealing end cap, and a set of bolts. The flange is installed at the end of the well shaft located in the low-pressure annulus by the set of bolts. The upper sealing end cap seals the port through the flange. A gasket is provided between the flange and the upper sealing end cap.

[0009] Preferably, it also includes a gas flow meter, and the upper sealing end cap is provided with a vent hole, on which the gas flow meter is installed.

[0010] Preferably, the drainage air pump includes an exhaust port, a low-pressure water inlet, a water outlet, and a high-pressure water inlet. The drainage air pump is provided with an exhaust port and a low-pressure water inlet in the low-pressure annulus, and the drainage air pump is provided with a water outlet and a high-pressure water inlet in the high-pressure annulus.

[0011] Preferably, the second sealing device includes a lower sealing end cap, a blind flange, and a set of No. 2 bolts. The blind flange is installed at the port of the well shaft located in the high-pressure annulus via the set of No. 2 bolts. The lower sealing end cap is sealed at the port position via the blind flange. A gasket is provided between the lower sealing end cap and the blind flange. The lower sealing end cap is provided with a water injection hole and an air injection hole. The water injection hole is connected to a water supply device, and the air injection hole is connected to an air supply device.

[0012] Preferably, the water conveying device includes a water conveying pipe, a water tank, and a water pump; the inlet of the water pump is connected to the water tank, and the outlet is connected to the water injection hole through the water conveying pipe; a first one-way valve and a second flow meter are provided on the water conveying pipe.

[0013] Preferably, the outlet of the drainage gas pump extending to the wellbore is connected to a drainage pipe, the drainage pipe is connected to a water tank, and the drainage pipe is equipped with a first pressure gauge, a first flow meter, and an overflow valve.

[0014] Preferably, the gas delivery device includes a first one-way valve, a pressure control valve, a high-pressure gas delivery pipe, a high-pressure air compressor, and a gas storage tank; the air inlet of the high-pressure air compressor is connected to the gas storage tank, and the air outlet is connected to the air injection port through the high-pressure gas delivery pipe; a pressure control valve is provided on the high-pressure gas delivery pipe.

[0015] Preferably, the detection device includes a water level gauge, a thermometer, and a second pressure gauge, all of which are mounted on the outer annular surface of the wellbore, with the detection end extending into the high-pressure annulus.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] 1. This invention provides accurate and effective data support for improving the drainage and gas extraction process by installing a detection device on the wellbore to monitor the gas pressure and fluid inside the high-pressure annulus in real time.

[0018] 2. By setting up a support device, the wellbore can be angled by an angle control frame, allowing the wellbore to simulate inclined wells at different angles for experiments. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the assembly structure of the device of the present invention;

[0020] Figure 2 This is a schematic diagram of the support ring structure of the present invention;

[0021] Figure 3 This is a schematic diagram of the internal cross-sectional structure of the flange of the present invention.

[0022] In the diagram: 1. Angle control frame; 2. Hydraulic lifting rod; 3. Fixed support frame; 301. Rotating pair; 4. Air compressor; 5. High-pressure air transmission pipe; 6. Air storage tank; 7. Vent hole; 8. First pressure gauge; 9. First flow meter; 10. Overflow valve; 11. Air flow meter; 12. Flange; 13. Upper sealing end cover; 14. No. 1 bolt group; 15. Drainage and air pump; 1501. Exhaust port; 1502. Low-pressure water inlet; 1503. Water outlet; 1504. High-pressure water inlet and air inlet; 16. 17. Sealing sleeve; 17. Well shaft; 1701. Low-pressure annulus; 1702. High-pressure annulus; 18. Water level gauge; 19. Support ring; 20. Thermometer; 21. Second pressure gauge; 22. Heating device; 23. Lower sealing end cap; 24. Blind flange; 25. No. 2 bolt group; 26. First check valve; 27. Second flow meter; 28. Water supply pipe; 29. ​​Water pump; 30. Drain pipe; 31. Water injection hole; 32. Air injection hole; 33. Second check valve; 34. Pressure control valve; 35. Water tank. Detailed Implementation

[0023] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] The following description, in conjunction with the accompanying drawings and specific embodiments, provides further details:

[0025] Example 1

[0026] like Figure 1 , Figure 2 and Figure 3As shown, a test bench for simulating a downhole drainage and gas production pump includes a wellbore 17, a drainage and gas production pump 15, a water delivery device, and a gas delivery device. It also includes a support device, which comprises an angle control frame 1, a hydraulic lifting rod 2, and a fixed support frame 3. One end of the fixed support frame 3 is equipped with a rotating joint 301, and the other end is equipped with the hydraulic lifting rod 2. The angle control frame 1 is rotatable above the fixed support frame 3 via the hydraulic lifting rod 2 and the rotating joint 301. The wellbore 17 is mounted on the angle control frame 1, and the angle of the wellbore 17 is changed by the raising and lowering of the hydraulic lifting rod 2 and the rotation of the rotating joint 301. The wellbore 17 contains a support ring 19 and a sealing sleeve 1. 6. The well shaft 17 is sealed at both ends with a first sealing device and a second sealing device. The first sealing device includes a flange 12, an upper sealing end cover 13, and a set of bolts 14. The flange 12 is set at one end of the well shaft 17 located in the low-pressure annulus 1701 through the set of bolts 14. The set of bolts 14 is evenly distributed in a ring and there are eight sets in total. The upper sealing end cover 13 seals the port through the flange 12. A gasket is provided between the flange 12 and the upper sealing end cover 13. In addition, a gas flow meter 11 is also included. The upper sealing end cover 13 is provided with a vent hole 7. A gas flow meter 11 is provided on the vent hole 7 to detect the amount of gas discharged by the drainage gas pump 15.

[0027] like Figure 1 and Figure 3As shown, the drainage and gas extraction pump 15 is annularly installed in the wellbore 17 via a support ring 19. The annular portion is divided into a low-pressure annulus 1701 and a high-pressure annulus 1702 by a sealing sleeve 16. A heating device 22 is installed on the wellbore 17 for heating the inside of the high-pressure annulus 1702, converting electrical energy into heat energy to heat the fluid inside the wellbore 17, simulating the high-temperature environment at the bottom of the well. The drainage and gas extraction pump 15 includes an exhaust port 1501, a low-pressure water inlet 1502, a water outlet 1503, and a high-pressure water inlet 1504. The drainage and gas extraction pump 15 has an exhaust port 1501 and a low-pressure water inlet 1502 located in the low-pressure annulus 1701, and a water outlet 1503 and a high-pressure water inlet 1504 located in the high-pressure annulus 1702. One end of the pump 15 is located in the high-pressure annulus 1702, and the other end extends through the first sealing device to the outside of the low-pressure annulus 1701 in the well shaft 17, and is connected to the inlet of the water conveying device through a pipeline. The second sealing device includes a lower sealing end cap 23, a blind flange 24, and a set of two bolts 25. The blind flange 24 is located at the port of the well shaft located in the high-pressure annulus 1702 through the set of two bolts 25. The set of two bolts 25 is evenly distributed in a ring and has eight sets. The lower sealing end cap 23 is sealed at the port position through the blind flange 24. A gasket is provided between the lower sealing end cap 23 and the blind flange 24 to ensure a tight seal. The lower sealing end cap 23 is provided with a water injection hole 31 and an air injection hole 32. The water injection hole 31 is connected to the water conveying device, and the air injection hole 32 is connected to the air conveying device.

[0028] like Figure 1As shown, the outlets of both the water delivery device and the gas delivery device are connected to the high-pressure annulus 1702 via pipelines. The water delivery device pumps water into the high-pressure annulus 1702 inside the wellbore 17 to simulate the water-bearing environment downhole. The gas delivery device introduces high-pressure gas into the high-pressure annulus 1702 to increase the gas pressure within the high-pressure annulus 1702, simulating the high-pressure environment at the bottom of the oil well. The water delivery device includes a water delivery pipe 28, a water tank 35, and a water pump 29. The inlet of the water pump 29 is connected to the water tank 35, and the outlet is connected to the water injection hole 31 via the water delivery pipe 28. A first one-way valve 26 and a second flow meter 27 are installed on the water delivery pipe 28. The outlet of the drainage and gas extraction pump 15, which extends to one end of the wellbore 17, is connected to a drainage pipe 30. The drainage pipe 30 is connected to the water tank 35 to achieve water recycling. The drainage pipe 30 is equipped with a first pressure gauge 8, a first flow meter 9, and an overflow valve 10. 10 is used to control the outlet pressure of the drainage and gas extraction pump 15. The first pressure gauge 8 and the first flow meter 9 are used to detect the water flow and pressure of the drainage and gas extraction pump 15. The gas transmission device includes a second one-way valve 33, a pressure control valve 34, a high-pressure gas transmission pipe 5, a high-pressure air compressor 4, and a gas storage tank 6. The air inlet of the high-pressure air compressor 4 is connected to the gas storage tank 6, and the air outlet is connected to the air injection hole 32 through the high-pressure gas transmission pipe 5. The high-pressure gas transmission pipe 5 is equipped with a pressure control valve 34, which is used to control the pressure input into the well barrel 17. A detection device is installed on the well barrel 17. The detection device includes a water level gauge 18, a thermometer 20, and a second pressure gauge 21. The water level gauge 18, the thermometer 20, and the second pressure gauge 21 are all installed on the outer ring surface of the well barrel 17, and the detection end extends into the high-pressure annulus 1702, which is used to measure the internal fluid data of the high-pressure annulus 1702.

[0029] Example 2

[0030] like Figure 1 , Figure 2 and Figure 3As shown, a test bench for simulating a downhole drainage and gas production pump includes a wellbore 17, a drainage and gas production pump 15, a water delivery device, and a gas delivery device. It also includes a support device, which comprises an angle control frame 1, a hydraulic lifting rod 2, and a fixed support frame 3. One end of the fixed support frame 3 is equipped with a rotating joint 301, and the other end is equipped with the hydraulic lifting rod 2. The angle control frame 1 is rotatable above the fixed support frame 3 via the hydraulic lifting rod 2 and the rotating joint 301. The wellbore 17 is mounted on the angle control frame 1, and the wellbore 17 contains a support ring 19 and a sealing rubber sleeve. 16. The well shaft 17 is sealed at both ends with a first sealing device and a second sealing device respectively. The first sealing device includes a flange 12, an upper sealing end cover 13, and a set of bolts 14. The flange 12 is set at one end of the well shaft 17 located in the low-pressure annulus 1701 through the set of bolts 14. The upper sealing end cover 13 seals the port through the flange 12. A gasket is provided between the flange 12 and the upper sealing end cover 13. In addition, it also includes a gas flow meter 11. The upper sealing end cover 13 is provided with a vent hole 7, and the gas flow meter 11 is installed on the vent hole 7.

[0031] like Figure 1 and Figure 3 As shown, the drainage and air-gathering pump 15 is annularly mounted in the wellbore 17 via a support ring 19, and the annular portion is divided into a low-pressure annulus 1701 and a high-pressure annulus 1702 by a sealing sleeve 16. A heating device 22 for heating the interior of the high-pressure annulus 1702 is provided on the wellbore 17. The drainage and air-gathering pump 15 includes an exhaust port 1501, a low-pressure suction port 1502, a water outlet 1503, and a high-pressure suction air inlet 1504. The exhaust port 1501 and the low-pressure suction port 1502 are located at the low-pressure annulus 1701, and the water outlet 1503 and the high-pressure suction air inlet 1504 are located at the high-pressure annulus 1702. One pump port is located in the high-pressure annulus 1702, and the other pump port extends through the first sealing device to the outside of the low-pressure annulus 1701 in the well shaft 17, and is connected to the inlet of the water supply device through a pipeline; the second sealing device includes a lower sealing end cap 23, a blind flange 24, and a set of No. 2 bolts 25. The blind flange 24 is located at the port of the well shaft located in the high-pressure annulus 1702 through the set of No. 2 bolts 25, and the lower sealing end cap 23 is sealed at the port position through the blind flange 24; a gasket is provided between the lower sealing end cap 23 and the blind flange 24, and the lower sealing end cap 23 is provided with a water injection hole 31 and an air injection hole 32. The water injection hole 31 is connected to the water supply device, and the air injection hole 32 is connected to the air supply device.

[0032] like Figure 1As shown, the outlets of both the water supply device and the gas supply device are connected to the high-pressure annulus 1702 via pipelines. The water supply device includes a water supply pipe 28, a water tank 35, and a water pump 29. The inlet of the water pump 29 is connected to the water tank 35, and the outlet is connected to the water injection hole 31 via the water supply pipe 28. A first check valve 26 and a second flow meter 27 are installed on the water supply pipe 28. The outlet of the drainage gas pump 15 extending to the well shaft 17 is connected to a drainage pipe 30, which is connected to the water tank 35. A first pressure gauge 8, a first flow meter 9, and an overflow valve 10 are installed on the drainage pipe 30. The gas supply device... It includes a second one-way valve 33, a pressure control valve 34, a high-pressure gas transmission pipe 5, a high-pressure air compressor 4, and a gas storage tank 6; the air inlet of the high-pressure air compressor 4 is connected to the gas storage tank 6, and the air outlet is connected to the air injection port 32 through the high-pressure gas transmission pipe 5. A pressure control valve 34 is installed on the high-pressure gas transmission pipe 5; a detection device is installed on the well shaft 17, which includes a water level gauge 18, a thermometer 20, and a second pressure gauge 21. The water level gauge 18, the thermometer 20, and the second pressure gauge 21 are all installed on the outer ring surface of the well shaft 17, and the detection end extends into the high-pressure annulus 1702.

[0033] The working principle of this invention is as follows: The well shaft 17 is tilted to a suitable position using the angle control frame 1. The water pump 29 draws water from the water tank into the well shaft 17 through the water injection hole 31. The water level gauge 18 is used to observe whether the water level is sufficient, and the second flow meter 27 is used to record the total water pumped. The water in the well shaft 17 is heated by the heating device 22, and the temperature is maintained by the thermometer 20 when the water reaches a suitable temperature. High-pressure air is generated by the air compressor 4 and drawn into the well shaft 17 through the air injection hole 32. The drainage and air extraction pump 15 starts working, drawing water through the high-pressure water intake port 1504. Water in well 17 is discharged through drain pipe 30, and the pressure of the discharged water is controlled by overflow valve 10. First pressure gauge 8 and first flow meter 9 record the pressure and flow rate of the discharged water. Low pressure suction port 1502 is used to suck up water that may exist in low pressure annulus 1701, and discharges it to high pressure annulus 1702 through outlet 1503, and then it is carried to drain pipe 30. The extracted air is discharged through exhaust port 1501, and the volume of discharged air is recorded by air flow meter 11, thereby detecting the flow rate of water that the drainage air pump can suck in and discharge within a specified time, as well as the pressure of discharged water and discharged air.

[0034] In summary, this invention provides accurate and effective data support for improving the drainage and gas production process by setting a detection device on the wellbore 17 to monitor the gas pressure and fluid inside the high-pressure annulus 1702 in real time. By setting a support device, the wellbore 17 can be angled by the angle control frame 1, allowing the wellbore 17 to simulate inclined wells at different angles for experiments.

[0035] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A test bench for simulating a downhole drainage and gas extraction pump, comprising a wellbore (17), a drainage and gas extraction pump (15), a water delivery device, and a gas delivery device, characterized in that, The well shaft (17) has an internal support ring (19) and a sealing sleeve (16). The two ends of the well shaft (17) are respectively sealed with a first sealing device and a second sealing device. The drainage and gas extraction pump (15) is annularly arranged in the well shaft (17) through the support ring (19), and the annular part is divided into a low-pressure annulus (1701) and a high-pressure annulus (1702) through the sealing sleeve (16). The well shaft (17) is provided with a heating device (22) for heating the inside of the high-pressure annulus (1702). One end of the drainage and gas extraction pump (15) is located in the high-pressure annulus (1702), and the other end of the pump extends through the first sealing device to the outside of the low-pressure annulus (1701) in the well shaft (17), and is connected to the inlet of the water conveying device through a pipeline. The outlets of the water conveying device and the gas conveying device are both connected to the high-pressure annulus (1702) through pipelines. The well shaft (17) is provided with a detection device.

2. The simulated downhole drainage and gas production pump testing test bench according to claim 1, characterized in that, It also includes a support device, which includes an angle control frame (1), a hydraulic lifting rod (2), and a fixed support frame (3); one end of the fixed support frame (3) is provided with a rotating joint (301), and the other end is provided with a hydraulic lifting rod (2); the angle control frame (1) is rotatable above the fixed support frame (3) through the hydraulic lifting rod (2) and the rotating joint (301); the well shaft (17) is set on the angle control frame (1).

3. The simulated downhole drainage and gas extraction pump testing test bench according to claim 1, characterized in that, The first sealing device includes a flange (12), an upper sealing end cap (13), and a set of bolts (14). The flange (12) is set at one end of the well shaft (17) located in the low-pressure annulus (1701) by the set of bolts (14). The upper sealing end cap (13) seals the port by means of the flange (12). A gasket is provided between the flange (12) and the upper sealing end cap (13).

4. The simulated downhole drainage and gas extraction pump testing test bench according to claim 3, characterized in that, It also includes a gas flow meter (11), and the upper sealing end cap (13) is provided with a vent hole (7), and the vent hole (7) is provided with a gas flow meter (11).

5. The test bench for simulating downhole drainage and gas production pumps according to claim 1, characterized in that, The drainage and air extraction pump (15) includes an exhaust port (1501), a low-pressure water inlet (1502), a water outlet (1503), and a high-pressure water inlet (1504). The drainage and air extraction pump (15) is provided with an exhaust port (1501) and a low-pressure water inlet (1502) at the position of the low-pressure annulus (1701), and is provided with a water outlet (1503) and a high-pressure water inlet (1504) at the position of the high-pressure annulus (1702).

6. The test bench for simulating downhole drainage and gas production pumps according to claim 1, characterized in that, The second sealing device includes a lower sealing end cap (23), a blind flange (24), and a set of No. 2 bolts (25). The blind flange (24) is installed at the port of the well shaft located in the high-pressure annulus (1702) through the set of No. 2 bolts (25). The lower sealing end cap (23) is sealed at the port position through the blind flange (24). A gasket is provided between the lower sealing end cap (23) and the blind flange (24). The lower sealing end cap (23) is provided with a water injection hole (31) and an air injection hole (32). The water injection hole (31) is connected to the water supply device, and the air injection hole (32) is connected to the air supply device.

7. The test bench for simulating downhole drainage and gas extraction pumps according to claim 6, characterized in that, The water conveying device includes a water conveying pipe (28), a water tank (35), and a water pump (29); the inlet of the water pump (29) is connected to the water tank (35), and the outlet is connected to the water injection hole (31) through the water conveying pipe (28); a first one-way valve (26) and a second flow meter (27) are provided on the water conveying pipe (28).

8. The test bench for simulating downhole drainage and gas extraction pumps according to claim 7, characterized in that, The outlet of the drainage gas pump (15) extending to the wellbore (17) is connected to a drainage pipe (30), the drainage pipe (30) is connected to a water tank (35), and the drainage pipe (30) is equipped with a first pressure gauge (8), a first flow meter (9), and an overflow valve (10).

9. The test bench for simulating downhole drainage and gas extraction pumps according to claim 6, characterized in that, The gas delivery device includes a first one-way valve (33), a pressure control valve (34), a high-pressure gas delivery pipe (5), a high-pressure air compressor (4), and a gas storage tank (6); the air inlet of the high-pressure air compressor (4) is connected to the gas storage tank (6), and the air outlet is connected to the air injection hole (32) through the high-pressure gas delivery pipe (5). The high-pressure gas delivery pipe (5) is equipped with a pressure control valve (34).

10. The test bench for simulating downhole drainage and gas production pumps according to claim 1, characterized in that, The detection device includes a water level gauge (18), a thermometer (20), and a second pressure gauge (21). The water level gauge (18), the thermometer (20), and the second pressure gauge (21) are all installed on the outer ring surface of the well barrel (17), and the detection end extends into the high-pressure annulus (1702).

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