Device and method for intelligently and rapidly detecting hole sealing quality of gas extraction drill hole

Abstract

The invention discloses a device and a method for intelligently and quickly detecting the hole sealing quality of a gas extraction drill hole, a gas extraction pipe in a gas extraction device is used for sealing the gas extraction drill hole and performing gas extraction, and the gas extraction pipe is used for collecting gas in the drill hole and conveying the gas into a subsequent detection device; the gas detection module in the detection device can detect data of flowing gas, the hole sealing quality judgment module compares and analyzes the detection data and a threshold value according to the preset threshold value, so that the hole sealing quality of a drilled hole is rapidly judged, and a result is displayed through the display device. At the moment, workers can perform subsequent construction according to a judgment result; and the hole sealing quality judgment module records monitoring data of gas collected each time and is used for updating a threshold value, the precision of judging the hole sealing quality of the drilled hole is improved in a dynamic updating mode, the judgment process does not need manual experience, the judgment consistency is guaranteed, and in addition, the size is small, operation is convenient, and good popularization value is achieved.

Description

Technical Field

[0001] The invention relates to an intelligent rapid detection device and method for gas extraction drilling hole sealing quality, belonging to the technical field of coal mine gas extraction. Background Art

[0002] Gas problems associated with coal mining, especially coal and gas outbursts and gas explosion accidents, constitute a major hidden danger to coal mine safety production. Coal mine gas extraction technology, as one of the fundamental control measures to solve coal mine gas problems, has been widely used in many coal mines at home and abroad. In this process, sealing the gas extraction boreholes is the basis and guarantee for the efficient implementation of gas extraction, and the sealing quality of the gas extraction boreholes is the key factor to ensure the effect of gas extraction. During the gas extraction process, due to the disturbance of ground stress and the mining stress of the surrounding coal seams, the coal body around the gas extraction boreholes will be damaged and deformed, and cracks or fissures will appear, causing the quality of gas extraction borehole sealing to deteriorate, thereby affecting the gas extraction effect. Therefore, regular inspection of the sealing quality of gas extraction boreholes can timely detect changes in the sealing quality of gas extraction boreholes, and take countermeasures to ensure efficient gas extraction.

[0003] At present, the methods for detecting the sealing quality of gas extraction boreholes mostly rely on detecting the internal pressure of the borehole or the gas composition data and judging based on manual experience. This method has the limitations of single consideration indicators and lack of systematicity and intelligence. The subjectivity of manual judgment and the lack of scientificity of judgment lead to inconsistent judgment standards among different workers, which in turn restricts the popularization and promotion of the detection method in practical applications. In addition, the existing detection devices are generally large in size and complicated to operate, and cannot achieve rapid detection of the sealing quality of gas extraction boreholes and accurate detection anytime and anywhere.

[0004] Therefore, how to provide a new device and method that can quickly and accurately judge the sealing quality without manual experience, ensure the consistency of judgment, and have a small size and easy operation is the research direction required by this application. Summary of the invention

[0005] In view of the problems existing in the above-mentioned prior art, the present invention provides an intelligent rapid detection device and method for the sealing quality of gas extraction drilling holes, which can quickly and accurately judge the sealing quality without manual experience and ensure the consistency of judgment, and has a small size and is easy to operate.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an intelligent rapid detection device for gas extraction drilling hole sealing quality, including a gas extraction device and a detection device;

[0007] The gas extraction device comprises a gas extraction pipe and a gas extraction pipe, one end of the gas extraction pipe extends into the borehole, and is used to extract gas inside the borehole; one end of the gas extraction pipe passes through the gas extraction pipe and extends into the borehole, and the other end is outside the borehole, and is used to collect gas at the end of the gas extraction pipe inside the borehole; the other end of the gas extraction pipe outside the borehole is connected to the main extraction pipeline through a tee, one end of the gas extraction pipe is equipped with a filter screen, which is used to prevent coal dust from entering the gas extraction pipe and blocking the pipeline, and the other end of the gas extraction pipe extends from the tee and is provided with a valve switch, which is used to control the on and off of the gas extraction pipe;

[0008] The detection device includes a shell, a micro-extraction pump, a gas detection module, a sealing quality judgment module and an air pipe. An air inlet and an exhaust port are respectively provided on both sides of the shell. The air pipe is installed in the shell and its two ends are respectively connected to the air inlet and the exhaust port. The material of the air pipe is PVC flame-retardant pipe; the gas extraction pipe is connected to the air pipe through the air inlet from the outside, and is used to transport the collected gas into the air pipe; the micro-extraction pump is installed on the air pipe, and is used to provide extraction negative pressure inside the air pipe; a closed cavity is provided on the air pipe, and the gas detection module is installed in the closed cavity, and is used to detect gas data flowing through the air pipe; a display device is installed on the surface of the shell, and is used to display the received content; the sealing quality judgment module is connected to the display device and the gas detection module, and is used to obtain the detection data of the gas detection module, analyze and process it, and then judge the sealing quality of the borehole, and display it through the display device.

[0009] Furthermore, it also includes a control switch, which is installed on the surface of the shell; the control switch includes switch button 1, switch button 2, switch button 3 and switch button 4, switch button 1 is used to control the overall power supply of the detection device, switch button 2 is used to control the on and off of the power supply of the micro-extraction pump, switch button 3 is used to control the on and off of the power supply of the gas detection module, and switch button 4 is used to control the on and off of the power supply of the sealing quality judgment module.

[0010] Furthermore, the gas extraction pipe is formed by coaxially connecting multiple hollow pipes with a length of 1 m and a diameter of 20 mm through sealing threads, and the length of the gas extraction pipe is adjusted according to the drilling depth; the hollow pipe is made of aluminum-plastic material.

[0011] Furthermore, the gas detection module includes an oxygen concentration sensor, a gas concentration sensor, a negative pressure sensor and a flow sensor, which are respectively used to detect the oxygen concentration, gas concentration, negative pressure and flow of the gas in the trachea; the trachea is made of PVC flame-retardant tube; the measurement range of the oxygen concentration sensor is 0-25%, the measurement range of the gas concentration sensor is 0-100%, the measurement range of the negative pressure sensor is 0-200kPa, and the flow rate measurement range of the flow sensor is 0-30m / s (bidirectional flow rate).

[0012] Furthermore, the other end of the gas extraction pipe is connected to the gas inlet through a quick-connect connector, which is convenient for connection and disassembly.

[0013] Furthermore, the vacuum degree generated by the micro extraction pump is much greater than the negative pressure value in the gas extraction pipe.

[0014] The working method of the above-mentioned gas extraction drilling hole sealing quality intelligent rapid detection device comprises the following specific steps:

[0015] A. Assemble the rapid detection device: First, when sealing the gas extraction borehole, determine the length S2 of the gas extraction pipe required to be pre-installed according to the total length S1 of the gas extraction pipe used in each gas extraction borehole, place the gas extraction pipe in the corresponding gas extraction pipe, and assemble all parts;

[0016] B. Initial inspection of the sealing quality of gas extraction boreholes: After the gas extraction boreholes are sealed, the gas in the boreholes is pre-extracted through the gas extraction pipe. During pre-extraction, the gas inlet of the detection device is connected to the other end of the gas extraction pipe, and then the valve switch is opened and the detection device is started to allow the gas in the borehole to enter the air pipe through the gas extraction pipe. The gas data in the air pipe is detected by the gas detection module, and the data is fed back to the sealing quality judgment module. After the sealing quality judgment module analyzes and processes the data, it makes an initial judgment on the sealing quality of the gas extraction boreholes. If the sealing quality is qualified, If it is proved that the borehole can continue to be used for gas extraction, the detection device and valve switch are closed, and the detection device is disconnected from the gas extraction pipe; if the sealing quality is unqualified, the cause of the situation is further determined manually. If it is a drilling failure, the borehole is completely blocked and gas extraction is no longer carried out; if it is caused by the lack of sealing materials, the borehole is further blocked, and after blocking, the test is continued, and the test-blocking steps are repeated until the test is qualified. After the test is qualified, the borehole continues to be used for gas extraction, the detection device and valve switch are closed, and the detection device is disconnected from the gas extraction pipe;

[0017] C. After the initial inspection of a borehole is completed, repeat step B to inspect the next borehole until the initial inspection of the sealing quality of all gas extraction boreholes is completed;

[0018] D. Inspection of the quality of gas extraction borehole sealing during gas extraction: When the quality of gas sealing needs to be regularly inspected during gas extraction, connect the gas inlet of the detection device to the other end of the gas extraction pipe, and repeat the process of step B to determine the quality of the borehole sealing. After the inspection, turn off the detection device and the valve switch, and disconnect the detection device from the gas extraction pipe;

[0019] E. After one borehole is inspected, repeat step D to inspect the next borehole until the sealing quality of all gas extraction boreholes during the extraction process is inspected.

[0020] Furthermore, the specific steps for determining the quality of borehole sealing in step B are as follows:

[0021] The borehole sealing quality determination module receives the detection data fed back by the gas detection module, which includes the oxygen concentration, gas concentration, air pressure, and flow rate of the gas.

[0022] The oxygen concentration threshold preset in the borehole sealing quality determination module is set to Q o , and the gas concentration threshold is set to Q w . When the detected oxygen concentration is higher than Q o or the detected gas concentration is lower than Q w , it is directly determined that the gas sealing quality of the borehole is unqualified; let the oxygen concentration detected by the gas detection module be Q1 and the methane concentration be Q2. If Q1 = 0 and Q2 = 100%, the borehole sealing quality effect of the gas drainage borehole is very good; if 0 < Q1 < Q o , Q w < Q2 < 100%, continuous monitoring is carried out and the following judgment is made:

[0023] If the oxygen concentration continues to increase, the gas concentration continues to decrease, and the drainage negative pressure continues to decrease, the borehole sealing quality effect deteriorates. According to the changing concentration of the gas and the amplitude of the decrease in the drainage negative pressure, the degree of deterioration of the borehole sealing quality is judged and then divided into qualified or unqualified; if the oxygen concentration continues to increase, the gas concentration continues to decrease, and the flow rate remains basically unchanged (i.e., the flow rate fluctuation range is less than 5%), it is judged that the borehole sealing quality effect deteriorates. According to the changing amplitude of the two gas concentrations, the degree of deterioration of the borehole sealing quality is judged and then divided into qualified or unqualified.

[0024] Furthermore, the thresholds set in the borehole sealing quality determination module include the oxygen concentration threshold and the gas concentration threshold, which are set through in-depth analysis and summary of the borehole sealing quality conditions of a large number of boreholes and their corresponding oxygen concentrations and gas concentrations. Different oxygen concentrations, gas concentrations, negative pressure changes, and flow rate changes correspond to different borehole sealing quality conditions, and the parameter thresholds change dynamically as the number of boreholes collected and detected increases each time.

[0025] Compared with the prior art, the present invention adopts a combination of a gas extraction device and a detection device. The gas extraction tube in the gas extraction device is used to seal the gas extraction borehole and extract gas. The gas extraction tube is used to collect the gas in the borehole and transport it to the subsequent detection device. The gas detection module in the detection device can detect the gas data flowing through, including the oxygen concentration, gas concentration, negative pressure and flow rate of the gas, and feed the detection data back to the sealing quality judgment module. The sealing quality judgment module compares and analyzes the detection data with the threshold according to a preset threshold, so as to quickly judge the sealing quality of the borehole, and display the result through a display device. At this time, the workers can perform subsequent construction according to the judgment result; and the sealing quality judgment module records the monitoring data of each gas collection for updating the threshold, and improves the accuracy of judging the quality of drilling hole sealing by dynamic updating. The judgment process does not require manual experience, thereby ensuring the consistency of judgment. In addition, it is small in size and easy to operate, and has good promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the internal structure of the detection device in the present invention.

[0028] In the figure: 1-coal seam, 2-gas extraction pipe, 3-coal seam bottom plate, 4-sealing material, 5-gas extraction pipe, 6-shell, 7-quick plug connector, 8-tee, 9-valve switch, 10-filter, 11-air inlet, 12-exhaust port, 13-micro extraction pump, 14-gas detection module, 141-sealed cavity, 142-oxygen concentration sensor, 143-gas concentration sensor, 144-negative pressure sensor, 145-flow sensor, 15-sealing quality judgment module, 16-display device, 17-trachea, 18-control switch, 181-switch button one, 182-switch button two, 183-switch button three, 184-switch button four, 19-micro power supply. DETAILED DESCRIPTION

[0029] The present invention will be further described below.

[0030] like Figure 1 As shown, a gas extraction drilling hole sealing quality intelligent rapid detection device includes a gas extraction device and a detection device;

[0031] The gas extraction device comprises a gas extraction pipe 2 and a gas extraction pipe 5. One end of the gas extraction pipe 2 extends into the borehole to extract gas inside the borehole. One end of the gas extraction pipe 5 passes through the gas extraction pipe 2 and extends into the borehole, and the other end is outside the borehole to collect gas at the end of the gas extraction pipe 2 inside the borehole. The other end of the gas extraction pipe 2 outside the borehole is connected to the main extraction pipeline through a tee 8. A filter screen 10 is installed at one end of the gas extraction pipe 5 to prevent coal dust from entering the gas extraction pipe 5 and blocking the pipeline. The other end of the gas extraction pipe 5 extends from the tee and is provided with a valve switch 9 to control the on and off of the gas extraction pipe 5.

[0032] like Figure 2 As shown, the detection device includes a shell 6, a micro-extraction pump 13, a gas detection module 14, a sealing quality judgment module 15 and an air pipe 17. The shell 6 is provided with an air inlet 11 and an exhaust port 12 on both sides. The air pipe 17 is installed in the shell 6 and its two ends are connected to the air inlet 11 and the exhaust port 12 respectively. The material of the air pipe 17 is a PVC flame-retardant pipe; the gas extraction pipe 5 is connected to the air pipe 17 from the outside through the quick-connect connector 7 and the air inlet 11, and is used to transport the collected gas into the air pipe 17; the micro-extraction pump 13 is installed on the air pipe 17, and is used to provide an extraction negative pressure inside the air pipe 17; and the vacuum degree generated by the micro-extraction pump 13 is much greater than the negative pressure value in the gas extraction pipe 2; a closed cavity 141 is provided on the air pipe 17, and the gas detection module 14 is installed in the closed cavity 141, and is used to detect the gas data flowing through the air pipe 17; the display device 16 is installed on the surface of the shell 6, and is used to display the received content for display; the sealing quality judgment module 15 is connected to the display device 16 and the gas detection module 14, and is used to obtain the detection data of the gas detection module 14 for analysis and processing to determine the sealing quality of the borehole, and display it through the display device 16; the micro power supply 19 supplies power to the detection device; the gas detection module 14 includes an oxygen concentration sensor 142, a gas concentration sensor 143, a negative pressure sensor 144 and a flow sensor 145, which are respectively used to detect the oxygen concentration, gas concentration, negative pressure and flow of the gas in the air pipe 17; the material of the air pipe 17 is PVC flame retardant pipe; the measurement range of the oxygen concentration sensor 142 is 0-25%, the measurement range of the gas concentration sensor 143 is 0-100%, the measurement range of the negative pressure sensor 144 is 0-200kPa, and the flow rate measurement range of the flow sensor 145 is 0-30m / s (bidirectional flow rate).

[0033] As an improvement of the present invention, it also includes a control switch 18, which is installed on the surface of the shell 6; the control switch 18 includes a switch button 181, a switch button 2 182, a switch button 3 183 and a switch button 4 184, the switch button 181 is used to control the power supply of the detection device as a whole, the switch button 2 182 is used to control the on and off of the power supply of the micro extraction pump 13, the switch button 3 183 is used to control the on and off of the power supply of the gas detection module 14, and the switch button 4 184 is used to control the on and off of the power supply of the sealing quality judgment module 15.

[0034] As another improvement of the present invention, the gas extraction pipe 5 is formed by coaxially connecting multiple hollow pipes with a length of 1m and a diameter of 20mm through sealing threads, and the length of the gas extraction pipe 5 is adjusted according to the drilling depth; the hollow pipe is made of aluminum-plastic material.

[0035] The working method of the above-mentioned gas extraction drilling hole sealing quality intelligent rapid detection device comprises the following specific steps:

[0036] A. Assembling the rapid detection device: First, when sealing the gas extraction borehole, determine the length S2 of the gas extraction pipe 5 that needs to be pre-installed according to the total length S1 of the gas extraction pipe 2 used in each gas extraction borehole, prepare a hollow pipe of corresponding length, connect it and place it in the corresponding gas extraction pipe 2, and assemble all parts;

[0037] B. Initial detection of gas extraction borehole sealing quality: After the gas extraction borehole is sealed, the gas in the borehole is pre-extracted through the gas extraction pipe 2. During the pre-extraction, the gas inlet 11 of the detection device is connected to the other end of the gas extraction pipe 5, and then the valve switch 9 is opened and the detection device is started, so that the gas in the borehole passes through the gas extraction pipe 5 and enters the air pipe 17, and the gas data in the air pipe 17 is detected by the gas detection module 14, and the data is fed back to the sealing quality determination module 15. After the sealing quality determination module 15 analyzes and processes the data, it makes an initial judgment on the sealing quality of the gas extraction borehole. The specific steps are as follows:

[0038] The sealing quality determination module 15 receives the detection data fed back by the gas detection module 14, which includes the oxygen concentration, gas concentration, gas pressure and flow rate of the gas;

[0039] The preset oxygen concentration threshold is set to Q in the sealing quality judgment module. o , the gas concentration threshold is set to Q w When the detected oxygen concentration is higher than Q o Or the detected gas concentration is lower than Q wIf so, it is directly determined that the gas sealing quality of the borehole is unqualified. Let the oxygen concentration detected by the gas detection module 14 be Q1 and the methane concentration be Q2. If Q1 = 0 and Q2 = 100%, the gas drainage borehole sealing quality effect is very good. If 0 < Q1 < Q o , Q w < Q2 < 100%, continuous monitoring is carried out and the following judgments are made:

[0040] If the oxygen concentration continues to increase, the gas concentration continues to decrease, and the drainage negative pressure continues to decrease, the borehole sealing quality effect becomes worse. According to the changing concentration of the gas and the decreasing amplitude of the drainage negative pressure, the degree of deterioration of the borehole sealing quality is judged and then classified as qualified or unqualified. If the oxygen concentration continues to increase, the gas concentration continues to decrease, and the flow rate remains basically unchanged (i.e., the flow rate fluctuation range is less than 5%), it is judged that the sealing quality effect becomes worse. According to the changing amplitude of the two gas concentrations, the degree of deterioration of the borehole sealing quality is judged and then classified as qualified or unqualified.

[0041] If the detected sealing quality is qualified, it proves that the borehole can continue the gas drainage work. Then, the detection device and the valve switch 9 are closed, and the detection device is disconnected from the gas drainage pipe 5. If the detected sealing quality is unqualified, the reason for this situation is further judged manually. If the borehole fails, the borehole is completely blocked and no gas drainage is carried out. If it is due to the lack of sealing material, the borehole continues to be blocked. After blocking, the detection is continued, and the detection-blocking steps are repeated until the detection is qualified. After the detection is qualified, the borehole continues the gas drainage work. The detection device and the valve switch 9 are closed, and the detection device is disconnected from the gas drainage pipe 5.

[0042] C. After the initial detection of a borehole is completed, repeat step B to detect the next borehole until the initial detection of the sealing quality of all gas drainage boreholes is completed.

[0043] D. Detection of the sealing quality of gas drainage boreholes during the drainage process: When it is necessary to regularly detect the gas sealing quality during the gas drainage process, connect the air inlet 11 of the detection device to the other end of the gas drainage pipe 5, and repeat the process of step B to judge the borehole sealing quality. After the detection is completed, the detection device and the valve switch 9 are closed, and the detection device is disconnected from the gas drainage pipe 5.

[0044] E. After the detection of a borehole is completed, repeat step D to detect the next borehole until the sealing quality of all gas drainage boreholes during the drainage process is detected.

[0045] The above method is further improved. The thresholds set in the sealing quality judgment module 15 include oxygen concentration thresholds and gas concentration thresholds, which are set through in-depth analysis and summary of a large number of borehole sealing quality conditions and their corresponding oxygen concentrations and gas concentrations. Different oxygen concentrations, gas concentrations, negative pressure changes and flow rate changes correspond to different sealing quality conditions, and the parameter thresholds change dynamically as the number of boreholes collected and tested increases each time.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An intelligent rapid detection device for gas extraction drilling and sealing quality, characterized in that: It includes a gas extraction device and a detection device; The gas extraction device comprises a gas extraction pipe and a gas extraction pipe, one end of the gas extraction pipe extends into the borehole, and is used to extract gas inside the borehole; one end of the gas extraction pipe passes through the gas extraction pipe and extends into the borehole, and the other end is outside the borehole, and is used to collect gas at the end of the gas extraction pipe inside the borehole; the other end of the gas extraction pipe outside the borehole is connected to the main extraction pipeline through a tee, one end of the gas extraction pipe is equipped with a filter screen, which is used to prevent coal dust from entering the gas extraction pipe and blocking the pipeline, and the other end of the gas extraction pipe extends from the tee and is provided with a valve switch, which is used to control the on and off of the gas extraction pipe; The detection device includes a shell, a micro-extraction pump, a gas detection module, a sealing quality judgment module and an air pipe, wherein an air inlet and an exhaust port are respectively arranged on both sides of the shell, the air pipe is installed in the shell and its two ends are respectively connected to the air inlet and the exhaust port; the gas extraction pipe is connected to the air pipe through the air inlet from the outside, and is used to transport the collected gas into the air pipe; the micro-extraction pump is installed on the air pipe, and is used to provide extraction negative pressure to the inside of the air pipe; a closed cavity is provided on the air pipe, and the gas detection module is installed in the closed cavity, and is used to detect gas data flowing through the air pipe; a display device is installed on the surface of the shell, and is used to display the received content; the sealing quality judgment module is connected to the display device and the gas detection module, and is used to obtain the detection data of the gas detection module, analyze and process it, and then judge the sealing quality of the borehole, and display it through the display device.

2. According to claim 1, the intelligent rapid detection device for gas extraction drilling hole sealing quality is characterized in that: It also includes a control switch, which is installed on the surface of the shell; the control switch includes switch button 1, switch button 2, switch button 3 and switch button 4, switch button 1 is used to control the overall power supply of the detection device, switch button 2 is used to control the on and off of the power supply of the micro-extraction pump, switch button 3 is used to control the on and off of the power supply of the gas detection module, and switch button 4 is used to control the on and off of the power supply of the sealing quality judgment module.

3. According to claim 1, the intelligent rapid detection device for gas extraction drilling hole sealing quality is characterized in that: The gas extraction pipe is formed by coaxially connecting multiple hollow pipes with a length of 1m and a diameter of 20mm through sealing threads. The length of the gas extraction pipe is adjusted according to the drilling depth; the hollow pipe is made of aluminum-plastic material.

4. According to claim 1, the intelligent rapid detection device for gas extraction drilling hole sealing quality is characterized in that: The gas detection module includes an oxygen concentration sensor, a gas concentration sensor, a negative pressure sensor and a flow sensor, which are respectively used to detect the oxygen concentration, gas concentration, negative pressure and flow of the gas in the trachea; the trachea is made of PVC flame-retardant tube.

5. According to claim 1, the intelligent rapid detection device for gas extraction drilling hole sealing quality is characterized in that: The other end of the gas extraction pipe is connected to the gas inlet through a quick-connect connector, which is easy to connect and disassemble.

6. According to claim 1, the intelligent rapid detection device for gas extraction drilling hole sealing quality is characterized in that: The vacuum degree generated by the micro extraction pump is much greater than the negative pressure value in the gas extraction pipe.

7. A working method of the intelligent rapid detection device for gas extraction drilling hole sealing quality according to any one of claims 1 to 6, characterized in that: The specific steps are: A. Assemble the rapid detection device: First, when sealing the gas extraction borehole, determine the length S2 of the gas extraction pipe required to be pre-installed according to the total length S1 of the gas extraction pipe used in each gas extraction borehole, place the gas extraction pipe in the corresponding gas extraction pipe, and assemble all parts; B. Initial inspection of the sealing quality of gas extraction boreholes: After the gas extraction boreholes are sealed, the gas in the boreholes is pre-extracted through the gas extraction pipe. During pre-extraction, the gas inlet of the detection device is connected to the other end of the gas extraction pipe, and then the valve switch is opened and the detection device is started to allow the gas in the borehole to enter the air pipe through the gas extraction pipe. The gas data in the air pipe is detected by the gas detection module, and the data is fed back to the sealing quality judgment module. After the sealing quality judgment module analyzes and processes the data, it makes an initial judgment on the sealing quality of the gas extraction boreholes. If the sealing quality is qualified, If it is proved that the borehole can continue to be used for gas extraction, the detection device and valve switch are closed, and the detection device is disconnected from the gas extraction pipe; if the sealing quality is unqualified, the cause of the situation is further determined manually. If it is a drilling failure, the borehole is completely blocked and gas extraction is no longer carried out; if it is caused by the lack of sealing materials, the borehole is further blocked, and after blocking, the test is continued, and the test-blocking steps are repeated until the test is qualified. After the test is qualified, the borehole continues to be used for gas extraction, the detection device and valve switch are closed, and the detection device is disconnected from the gas extraction pipe; C. After the initial inspection of a borehole is completed, repeat step B to inspect the next borehole until the initial inspection of the sealing quality of all gas extraction boreholes is completed; D. Inspection of the quality of gas extraction borehole sealing during gas extraction: When the quality of gas sealing needs to be regularly inspected during gas extraction, connect the gas inlet of the detection device to the other end of the gas extraction pipe, and repeat the process of step B to determine the quality of the borehole sealing. After the inspection, turn off the detection device and the valve switch, and disconnect the detection device from the gas extraction pipe; E. After one borehole is inspected, repeat step D to inspect the next borehole until the sealing quality of all gas extraction boreholes during the extraction process is inspected.

8. The working method according to claim 7, characterized in that: The specific steps of determining the quality of drilling and sealing in step B are: The sealing quality determination module receives the detection data fed back by the gas detection module, which includes the oxygen concentration, gas concentration, gas pressure and flow rate of the gas; Preset the oxygen concentration threshold in the borehole sealing quality determination module as Q o , and preset the gas concentration threshold as Q w . When the detected oxygen concentration is higher than Q o or the detected gas concentration is lower than Q w , directly determine that the gas borehole sealing quality is unqualified; Let the oxygen concentration detected by the gas detection module be Q1 and the methane concentration be Q2. If Q1 = 0 and Q2 = 100%, the borehole sealing quality of the gas drainage borehole is very good; If 0 < Q1 < Q o , Q w < Q2 < 100%, then continuously monitor and make the following judgments: If the oxygen concentration continues to increase, the gas concentration continues to decrease, and the extraction negative pressure continues to decrease, the quality of the borehole sealing will deteriorate. The degree of deterioration of the borehole sealing quality is judged according to the change in gas concentration and the amplitude of the reduction in the extraction negative pressure, and then it is classified as qualified or unqualified; if the oxygen concentration continues to increase, the gas concentration continues to decrease, and the flow rate remains basically unchanged, it is judged that the sealing quality has deteriorated. The degree of deterioration of the borehole sealing quality is judged according to the amplitude of the change in the concentrations of the two gases, and then it is classified as qualified or unqualified.

9. The working method according to claim 8, characterized in that: The thresholds set in the sealing quality judgment module include oxygen concentration thresholds and gas concentration thresholds, both of which are set through in-depth analysis and summary of a large number of borehole sealing quality conditions and their corresponding oxygen concentrations and gas concentrations. Different oxygen concentrations, gas concentrations, negative pressure changes and flow rate changes correspond to different sealing quality conditions, and the parameter thresholds change dynamically as the number of boreholes collected and tested increases each time.

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