A pressure-controlled gas volume testing system and testing method

Abstract

This invention belongs to the field of petroleum exploration technology and discloses a pressure-controlled gas volume testing system and method. The pressure-controlled gas volume testing system includes an inner cylinder, a pressure replenishing component, a gas volume testing component, a pressure gauge, a pressure control valve, and a control component. The pressure replenishing component is connected to the inner cylinder via a pipeline; the gas volume testing component is connected to the pressure replenishing component via a pipeline; the pressure gauge is used to test the pressure of the inner cylinder and the pressure replenishing component; the pressure control valve includes a first pressure control valve and a second pressure control valve, the first pressure control valve being located between the inner cylinder and the pressure replenishing component, and the second pressure control valve being located between the pressure replenishing component and the gas volume testing component; the control component is configured to control the opening of the first and second pressure control valves when the pressure difference between the first and second pressure gauges reaches a set threshold. The pressure-controlled gas volume testing system provided by this invention can accurately measure the gas volume in the pipeline at each pressure range, improving the accuracy of the measurement.

Description

Technical Field

[0001] This invention relates to the field of petroleum exploration technology, and in particular to a pressure-controlled gas volume testing system and testing method. Background Technology

[0002] The conventional method for analyzing core gas volume involves placing the core obtained using conventional coring techniques into an analysis tank, where the gas volume is analyzed. Because conventional cores are unpressurized, significant gas loss occurs during tripping, and this loss can only be calculated using formulas. In contrast, pressure-maintaining coring technology obtains pressurized cores, allowing for the collection of gas lost during tripping using conventional cores. The gas volume is directly measured, resulting in high reliability and accuracy.

[0003] Current shale gas core collection and metering methods employ rapid depressurization. This method utilizes the principle of drainage gas extraction, where the core pressure is rapidly released, and the shale gas in the core cylinder enters the drainage gas extraction tank in a gas-liquid mixed state. The amount of gas lost from the core under this pressure condition is calculated by calculating the drainage volume. However, this technology relies on manual control of the pressure release rate during collection, leading to significant arbitrariness. Due to the large gas volume, the extraction equipment requires multiple repeated drainage cycles before calculations can be performed, resulting in substantial human error. Furthermore, releasing the pressure to a normal state all at once makes it impossible to accurately study the pressure-gas volume relationship. Summary of the Invention

[0004] The purpose of this invention is to provide a controlled-pressure gas volume testing system and method to solve the problems of inaccurate gas volume measurement and insufficient gas collection in the prior art.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] A pressure-controlled gas volume testing system, comprising:

[0007] Inner cylinder, the inner cylinder being used to hold pressurized rock cores;

[0008] A pressure-reducing assembly is connected to the inner cylinder via a pipe, and the pressure-reducing assembly is used to pressurize the pipe;

[0009] A gas volume testing component is connected to the pressure replenishment component via a pipeline. The gas volume testing component is used to measure the gas volume of the pressurized core.

[0010] The pressure gauge includes a first pressure gauge and a second pressure gauge, wherein the first pressure gauge is used to test the pressure of the inner cylinder and the second pressure gauge is used to measure the pressure of the pressure compensation assembly.

[0011] The pressure control valve includes a first pressure control valve and a second pressure control valve. The first pressure control valve is located between the inner cylinder and the pressure replenishing assembly, and the second pressure control valve is located between the pressure replenishing assembly and the gas volume testing assembly.

[0012] A control unit is electrically connected to the first pressure gauge, the second pressure gauge, the first pressure control valve, and the second pressure control valve. The control unit is configured to control the opening of the first pressure control valve and the second pressure control valve when the pressure difference between the first pressure gauge and the second pressure gauge reaches a set threshold.

[0013] Optionally, the pressure compensation assembly includes a fluid buffer and a pressure-compensating variable pump interconnected by pipes. One end of the fluid buffer is connected to the first pressure control valve via a pipe, and the other end of the fluid buffer is connected to the second pressure control valve via a pipe. The pressure-compensating variable pump is electrically connected to the control unit, and the fluid buffer is connected to a second pressure gauge via a pipe.

[0014] Optionally, the gas volume testing component includes an automatic gas-liquid separator, a gas flow meter, and a liquid flow meter, wherein the gas flow meter and the liquid flow meter are both connected to the automatic gas-liquid separator via pipelines.

[0015] Optionally, the gas volume testing assembly further includes a gas collector, which is connected to the gas flow meter via a pipeline.

[0016] Optionally, the gas volume testing assembly further includes a gas dryer, which is located between the automatic gas-liquid separator and the gas flow meter, and is connected to the gas collector and the gas flow meter via a pipeline.

[0017] Optionally, the gas flow meter includes an instantaneous gas flow meter and a gas cumulative meter connected by a pipeline. The instantaneous gas flow meter is connected to the gas dryer, and the gas cumulative meter is connected to the gas collector.

[0018] Optionally, one end of the gas cumulative meter is provided with a gas sample collection interface, and the gas collector is connected to the gas sample collection interface.

[0019] Optionally, the pressure control gas volume testing system further includes an isolation screen, which is disposed between the inner cylinder and the pressure compensation component, and is used to isolate solid particles.

[0020] Optionally, the first pressure control valve is a one-way control valve.

[0021] A method for testing controlled-pressure gas volume, employing the controlled-pressure gas volume testing system described in any of the above schemes, is characterized by comprising the following steps:

[0022] S1. Perform pressure testing on the inner cylinder, the pressure replenishment assembly, the gas volume testing assembly, the pressure gauge, and the pressure control valve;

[0023] S2. The pressure of the inner cylinder is measured by the first pressure gauge, the pressure of the pressure compensation component is measured by the second pressure gauge, and a threshold value for the pressure difference between the first pressure gauge and the second pressure gauge is set.

[0024] S3. The control component controls the pressure replenishment assembly to pressurize the pipeline. When the pressure difference reaches a threshold, the control component controls the first pressure control valve and the second pressure control valve to open.

[0025] S4. The pressurized rock core inside the inner cylinder enters the gas volume testing component via the first pressure control valve and the second pressure control valve, and the gas volume testing component measures the gas volume of the pressurized rock core.

[0026] The beneficial effects of this invention are as follows: The pressure-controlled gas volume testing system provided by this invention, by setting up a pressure replenishment component, a gas volume testing component, and pressure gauges, including a first pressure gauge and a second pressure gauge, the first pressure gauge is used to test the pressure of the inner cylinder, and the second pressure gauge is used to measure the pressure of the pressure replenishment component. The first and second pressure gauges can record the pressure magnitude of the inner cylinder and the pressure replenishment component in real time, and the pressure gauge measurements are accurate. By setting up a pressure control valve and a control component, the pressure control valve includes a first pressure control valve and a second pressure control valve. The control component is configured to control the opening of the first and second pressure control valves when the pressure difference between the first and second pressure gauges reaches a set threshold. The gas volume testing component measures the gas volume of the pressurized core. By analyzing the relationship between the pressure of the inner cylinder and the gas volume, the reserve calculation equation can be optimized, and the measurement accuracy can be improved.

[0027] The pressure-controlled gas volume testing method provided by this invention can measure the gas volume of pressurized rock cores at different pressure ranges, thereby improving the accuracy and reliability of the measurement. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the pressure-controlled gas volume testing system provided by the present invention.

[0029] In the picture:

[0030] 1. Inner cylinder; 2. Pressure compensation assembly; 21. Fluid buffer; 22. Pressure-compensated variable pump; 31. Automatic gas-liquid separator; 32. Gas flow meter; 321. Instantaneous gas flow meter; 322. Gas cumulative meter; 3221. Gas sample collection interface; 33. Liquid flow meter; 34. Gas collector; 35. Gas dryer; 41. First pressure gauge; 42. Second pressure gauge; 51. First pressure control valve; 52. Second pressure control valve; 6. Control components; 7. Isolation screen. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0032] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" 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 based on the specific circumstances.

[0033] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0034] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0035] This embodiment provides a pressure-controlled gas volume testing system, such as Figure 1As shown, the pressure-controlled gas volume testing system includes an inner cylinder 1, a pressure replenishing component 2, a gas volume testing component, a pressure gauge, a pressure control valve, and a control element 6. The inner cylinder 1 is used to hold the pressurized rock core. The pressure replenishing component 2 is connected to the inner cylinder 1 via a pipeline and is used to pressurize the pipeline. The gas volume testing component is connected to the pressure replenishing component 2 via a pipeline and is used to measure the gas volume of the pressurized rock core. The pressure gauge includes a first pressure gauge 41 and a second pressure gauge 42. The first pressure gauge 41 is used to test the pressure of the inner cylinder 1, and the second pressure gauge 42 is used to measure the pressure of the pressure replenishing component 2. Pressure; the pressure control valve includes a first pressure control valve 51 and a second pressure control valve 52. The first pressure control valve 51 is located between the inner cylinder 1 and the pressure replenishing component 2, and the second pressure control valve 52 is located between the pressure replenishing component 2 and the gas volume testing component. The control element 6 is electrically connected to the first pressure gauge 41, the second pressure gauge 42, the first pressure control valve 51, and the second pressure control valve 52. The control element 6 is configured to control the opening of the first pressure control valve 51 and the second pressure control valve 52 when the pressure difference between the first pressure gauge 41 and the second pressure gauge 42 reaches a set threshold.

[0036] The pressure-controlled gas volume testing system provided by this invention includes a pressure replenishment component 2, a gas volume testing component, and pressure gauges. The pressure gauges include a first pressure gauge 41 and a second pressure gauge 42. The first pressure gauge 41 is used to test the pressure of the inner cylinder 1, and the second pressure gauge 42 is used to measure the pressure of the pressure replenishment component 2. The first pressure gauge 41 and the second pressure gauge 42 can record the pressure magnitude of the inner cylinder 1 and the pressure replenishment component 2 in real time, and the pressure gauge measurements are accurate. By setting a pressure control valve and a control component 6, the pressure control valve includes a first pressure control valve 51 and a second pressure control valve 52. The control component 6 is configured to control the opening of the first pressure control valve 51 and the second pressure control valve 52 when the pressure difference between the first pressure gauge 41 and the second pressure gauge 42 reaches a set threshold. The gas volume testing component can measure the gas volume of the pressurized core. By analyzing the relationship between the pressure of the inner cylinder 1 and the gas volume, the reserve calculation equation can be optimized, and the measurement accuracy can be improved.

[0037] Optionally, the pressure compensation assembly 2 includes a fluid buffer 21 and a pressure-compensating variable pump 22 interconnected by pipes. One end of the fluid buffer 21 is connected to the first pressure control valve 51 via a pipe, and the other end of the fluid buffer 21 is connected to the second pressure control valve 52 via a pipe. The pressure-compensating variable pump 22 is electrically connected to the control component 6, and the fluid buffer 21 is connected to the second pressure gauge 42 via a pipe. By setting up the pressure compensation assembly 2, which includes the fluid buffer 21 and the pressure-compensating variable pump 22 interconnected by pipes, the pressure-compensating variable pump 22 can supplement the pressure of the fluid buffer 21 to provide pressure buffering, preventing large fluctuations in the pressure difference across the first pressure control valve 51, and improving the stability and accuracy of the test.

[0038] Preferably, the fluid buffer 21 is a large-capacity closed liquid container. This configuration can improve the uniformity and stability of pressure changes within the fluid buffer 21.

[0039] Preferably, the pressure-compensating variable pump 22 is a hydraulic pump. This configuration facilitates the replenishment of liquid to the fluid buffer 21 to adjust the pressure changes within the fluid buffer 21. Simultaneously, the hydraulic pump accurately records the amount of liquid used during the pressure compensation process, facilitating subsequent measurement of the liquid volume within the inner cylinder 1.

[0040] See also Figure 1 The gas volume testing component includes an automatic gas-liquid separator 31, a gas flow meter 32, and a liquid flow meter 33. Both the gas flow meter 32 and the liquid flow meter 33 are connected to the automatic gas-liquid separator 31 via pipes. By installing the automatic gas-liquid separator 31, it can separate the substance passing through the second pressure control valve 52 into gas and liquid. The gas flow meter 32 measures the amount of gas separated, and the liquid flow meter 33 measures the amount of liquid separated, thus improving the accuracy of the measurement.

[0041] Furthermore, the gas volume testing component also includes a gas collector 34, which is connected to the gas flow meter 32 via a pipe. By setting up the gas collector 34, the gas collector 34 can collect the gas discharged from the inner cylinder 1, so as to facilitate subsequent gas analysis and testing.

[0042] Optionally, the gas volume testing assembly also includes a gas dryer 35, which is located between the automatic gas-liquid separator 31 and the gas flow meter 32. The gas dryer 35 is connected to the gas collector 34 and the gas flow meter 32 via a pipe. By setting up the gas dryer 35, the gas still contains moisture after passing through the automatic gas-liquid separator 31. The gas dryer 35 dries the gas before the gas flow meter 32 measures the gas volume, thereby improving the accuracy of the gas flow meter 32 in measuring the gas volume.

[0043] Preferably, the gas flow meter 32 includes an instantaneous gas flow meter 321 and a gas cumulative meter 322 connected by a pipeline. The instantaneous gas flow meter 321 is connected to the gas dryer 35, and the gas cumulative meter 322 is connected to the gas collector 34. By setting the instantaneous gas flow meter 321 and the gas cumulative meter 322, the instantaneous gas flow meter 321 can measure the instantaneous gas volume within a certain pressure range, and the gas cumulative meter 322 can measure the cumulative gas volume throughout the entire test process, thereby improving the accuracy and real-time performance of gas measurement.

[0044] To improve the reliability of the connection between the gas collector 34 and the gas accumulator 322, a gas sample collection interface 3221 is provided at one end of the gas accumulator 322, and the gas collector 34 is connected to the gas sample collection interface 3221. By setting the gas sample collection interface 3221, the installation stability between the gas collector 34 and the gas accumulator 322 is effectively improved, thereby improving the adequacy of gas collection.

[0045] Optionally, the pressure-controlled gas volume testing system also includes an isolation screen 7, which is located between the inner cylinder 1 and the pressure-replenishing component 2. The isolation screen 7 is used to isolate solid particles. When measuring the gas in the core of the pressure-holding inner cylinder 1, the space between the core and the pipe wall is filled with drilling fluid. The drilling fluid contains rock cuttings of different sizes. When the first pressure control valve 51 is opened, the rock cuttings are carried into the pipeline by the drilling fluid. To prevent the rock cuttings from clogging the pipeline, the isolation screen 7 is located between the inner cylinder 1 and the pressure-replenishing component 2 to isolate the rock cuttings. Specifically, the isolation screen 7 may include multiple layers of screen mesh. Based on actual needs, the screen mesh number can be increased from low to high, with the lowest mesh number near the inner cylinder 1 and the highest mesh number near the first pressure control valve 51, to achieve gradient isolation, reduce clogging, and improve the isolation effect of the isolation screen 7.

[0046] Preferably, the first pressure control valve 51 is a one-way control valve. This configuration prevents liquid in the fluid buffer 21 from flowing into the inner cylinder 1 when the pressure-compensated variable pump 22 replenishes pressure to the fluid buffer 21, thus avoiding affecting the accuracy of the measurement.

[0047] This embodiment also provides a method for testing controlled-pressure gas volume, including the following steps:

[0048] S1. Perform pressure testing on the inner cylinder 1, pressure replenishment assembly 2, air volume testing assembly, pressure gauge and pressure control valve;

[0049] Through pressure testing, the pressure resistance of the inner cylinder 1, pressure replenishment component 2, gas volume testing component, pressure gauge, and pressure control valve is ensured to be higher than the pressure of the formation to be tested, thereby improving system reliability.

[0050] S2. The pressure of the inner cylinder 1 is measured by the first pressure gauge 41, the pressure of the pressure compensation component 2 is measured by the second pressure gauge 42, and the threshold value of the pressure difference between the first pressure gauge 41 and the second pressure gauge 42 is set.

[0051] In the actual measurement process, by measuring the pressure of the inner cylinder 1 and the pressure compensation component 2, the threshold value of the pressure difference between the first pressure gauge 41 and the second pressure gauge 42 is set according to the magnitude of the pressure of the two and the actual measurement needs.

[0052] S3. The control unit 6 controls the pressure replenishment component 2 to pressurize the pipeline. When the pressure difference reaches the threshold, the control unit 6 controls the first pressure control valve 51 and the second pressure control valve 52 to open.

[0053] In actual measurement, the initial pressure of the pressure replenishing component 2 is generally less than the pressure in the inner cylinder 1. The control component 6 pre-controls the pressure replenishing component 2 to pressurize the pipeline so that the pressure difference between the first pressure gauge 41 and the second pressure gauge 42 reaches the set threshold.

[0054] Specifically, the control unit 6 can control the pressure compensation variable pump 22 to turn on, and the compensation variable pump 22 compensates the pressure of the fluid buffer 21 so that the pressure difference between the inner cylinder 1 and the fluid buffer 21 reaches a set threshold. When the pressure difference between the inner cylinder 1 and the fluid buffer 21 reaches the set threshold, the control unit 6 controls the pressure compensation variable pump 22 to turn off. At the same time, the control unit 6 controls the second pressure control valve 52 to turn on, the pressure of the fluid buffer 21 changes, the pressure difference between the inner cylinder 1 and the pressure compensation assembly 2 changes, and the control unit 6 controls the first pressure control valve 51 and the pressure compensation variable pump 22 to turn on, so that the pressure difference between the inner cylinder 1 and the fluid buffer 21 is always equal to the threshold, so as to achieve the stability and uniformity of pressure relief.

[0055] S4. The pressurized rock core in the inner cylinder 1 enters the gas volume testing component via the first pressure control valve 51 and the second pressure control valve 52. The gas volume testing component measures the gas volume of the pressurized rock core.

[0056] During the measurement process, the gas-liquid mixture of the pressurized core enters the automatic gas-liquid separator 31 via the first pressure control valve 51 and the second pressure control valve 52. The automatic gas-liquid separator 31 separates the gas and liquid. The liquid enters the liquid flow meter 33, which measures the liquid. The gas passes through the gas dryer 35, the instantaneous gas flow meter 321, and the gas cumulative meter 322 in sequence, and finally enters the gas sample collector 34.

[0057] In this embodiment, the pressure difference between the inner cylinder 1 and the pressure compensation component 2 can be set to the pressure of one inner cylinder 1. When the pressure difference is zero, the pressure control gas volume system is in a measurement stop state; when the pressure difference is equal to the pressure of the inner cylinder 1, the pressure control gas volume system is in a pressure relief state; when the pressure difference is greater than zero and less than the pressure of one inner cylinder 1, the pressure control gas volume system is in a pressure control measurement state. The smaller the pressure difference, the more accurate the gas measurement and the better for qualitative analysis. In other embodiments, those skilled in the art can set the pressure difference threshold according to actual needs.

[0058] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for controlled pressure gas volume testing, implemented using a controlled pressure gas volume testing system, characterized by, The system comprises: an inner cylinder (1) for accommodating a pressurized core; a pressure supplement assembly (2) connected with the inner cylinder (1) through a pipeline, the pressure supplement assembly (2) being used for pressurizing the pipeline; a gas volume testing assembly connected with the pressure supplement assembly (2) through a pipeline, the gas volume testing assembly being used for measuring the gas volume of the pressurized core; pressure gauges including a first pressure gauge (41) and a second pressure gauge (42), the first pressure gauge (41) being used for measuring the pressure of the inner cylinder (1), and the second pressure gauge (42) being used for measuring the pressure of the pressure supplement assembly (2); pressure control valves including a first pressure control valve (51) and a second pressure control valve (52), the first pressure control valve (51) being arranged between the inner cylinder (1) and the pressure supplement assembly (2), and the second pressure control valve (52) being arranged between the pressure supplement assembly (2) and the gas volume testing assembly; a control member (6) electrically connected with the first pressure gauge (41), the second pressure gauge (42), the first pressure control valve (51), the second pressure control valve (52) and the pressure supplement assembly (2), the control member (6) being configured to control the opening of the first pressure control valve (51) and the second pressure control valve (52) when the pressure difference between the first pressure gauge (41) and the second pressure gauge (42) reaches a set threshold value; The pressure control gas volume testing method comprises the following steps: S1, pressure testing is performed on the inner cylinder (1), the pressure supplement assembly (2), the gas volume testing assembly, the pressure gauges and the pressure control valves; S2, the pressure of the inner cylinder (1) is measured by the first pressure gauge (41), the pressure of the pressure supplement assembly (2) is measured by the second pressure gauge (42), and the threshold value of the pressure difference between the first pressure gauge (41) and the second pressure gauge (42) is set; S3, the control member (6) controls the pressure supplement assembly (2) to pressurize the pipeline, when the pressure difference reaches the threshold value, the control member (6) controls the first pressure control valve (51) and the second pressure control valve (52) to open, when the pressure difference changes, the control member (6) controls the first pressure control valve (51) and the pressure supplement assembly (2) to open, so that the pressure difference is always equal to the threshold value, to realize the stability and uniformity of pressure relief; S4, the gas of the pressurized core in the inner cylinder (1) enters the gas volume testing assembly through the first pressure control valve (51) and the second pressure control valve (52), and the gas volume of the pressurized core is measured by the gas volume testing assembly.

2. The method of claim 1, wherein, The pressure compensation assembly (2) comprises a fluid buffer (21) and a pressure compensation variable pump (22) connected with each other through pipelines, one end of the fluid buffer (21) is connected with the first pressure control valve (51) through a pipeline, the other end of the fluid buffer (21) is connected with the second pressure control valve (52) through a pipeline, the pressure compensation variable pump (22) is electrically connected with the control member (6), the fluid buffer (21) is connected with a second pressure gauge (42) through a pipeline, the fluid buffer (21) is a closed liquid container, and the pressure compensation variable pump (22) is a hydraulic pump.

3. The method of claim 1, wherein, The gas volume test assembly comprises an automatic gas-liquid separator (31), a gas flow meter (32) and a liquid flow meter (33), and the gas flow meter (32) and the liquid flow meter (33) are connected with the automatic gas-liquid separator (31) through pipelines.

4. The method of claim 3, wherein, The gas volume test assembly further comprises a gas collector (34), and the gas collector (34) is connected with the gas flow meter (32) through a pipeline.

5. The method of claim 4, wherein, The gas volume test assembly further comprises a gas dryer (35), and the gas dryer (35) is arranged between the automatic gas-liquid separator (31) and the gas flow meter (32), and the gas dryer (35) is connected with the gas collector (34) and the gas flow meter (32) through pipelines.

6. The method of claim 5, wherein, The gas flow meter (32) comprises a gas instantaneous flow meter (321) and a gas cumulative meter (322) connected through pipelines, the gas instantaneous flow meter (321) is connected with the gas dryer (35), and the gas cumulative meter (322) is connected with the gas collector (34).

7. The method of claim 6, wherein, One end of the gas cumulative meter (322) is provided with a gas sample collection interface (3221), and the gas collector (34) is in communication with the gas sample collection interface (3221).

8. The method of claim 1-7, wherein, The pressure-controlled gas volume test system further comprises an isolation screen (7), and the isolation screen (7) is arranged between the inner cylinder (1) and the pressure compensation assembly (2), and is used for isolating solid particles.

9. The method of claim 1-7, wherein, The first pressure control valve (51) is a one-way control valve.

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