Downhole directional long borehole bottom-hole space gas pressure measurement device and method while drilling

Abstract

The present invention belongs to the technical field of coal mining and coal mine safety, and discloses a device for measuring the gas pressure at the bottom of an underground directional long borehole while drilling, which includes a gas pressure detection mechanism, a plugging mechanism and a waterway closing mechanism connected in sequence. The waterway closing mechanism cuts off the waterway and drives the plugging mechanism to plug the bottom space of the borehole and drives the gas pressure detection mechanism to communicate with the bottom space of the borehole to complete the pressure measurement. The measuring device of the present invention has the advantages of ingenious design and simple structure. It can not only detect the gas pressure in the bottom space of the directional long borehole while drilling, but also realize multi-point detection of the gas pressure in the bottom space of the directional long borehole while drilling.

Description

Technical Field

[0001] The invention belongs to the technical fields of coal mining and coal mine safety, and particularly relates to a device and method for measuring the gas pressure in the bottom hole space of an underground directional long borehole while drilling. Background Technique

[0002] Detecting and mastering the gas content distribution of the coal seam exposed by the directional borehole is the basis for optimizing the design of gas drainage boreholes, and supporting fixed-point permeability enhancement such as directional fracturing and hydraulic slotting of long boreholes, improving the gas prevention and control effect in large areas, and realizing precise and efficient gas extraction. For the mature directional long borehole forming processes such as hard coal directional drilling and comb-shaped boreholes in the roof (floor) of soft and broken coal seams, the drilling length is generally greater than 300m. At present, the sampling desorption method is used to measure the gas content of the coal seam in the directional long borehole. Due to reasons such as shallow sampling depth, long sampling time, low sampling success rate, and single sampling point, the existing fixed-point sampling process cannot support the measurement of the gas content of the coal seam in the directional long borehole, seriously restricting the development of the large-area gas control technology for directional long boreholes.

[0003] However, by quickly plugging the small bottom hole space, detecting the characteristic parameters of the gas pressure recovery in the bottom hole space, and converting the characteristic parameters of the pressure recovery into the gas content of the coal seam at the detection point is one of the effective ways to obtain the gas content distribution of the coal seam exposed by the directional borehole while drilling.

[0004] Therefore, in order to quickly plug the small bottom hole space and detect the gas pressure in the bottom hole space, it is necessary to propose a device for measuring the gas pressure in the bottom hole space of an underground directional long borehole while drilling, so as to indirectly obtain the gas content parameters of the coal seam to guide the implementation of large-area gas control measures, which is of great significance for improving the large-area gas control effect and realizing precise and efficient gas extraction. Summary of the Invention

[0005] In view of this, aiming at the deficiencies of the existing technology for measuring the gas content of the coal seam in the directional long borehole, the purpose of the invention is to provide a device and method for measuring the gas pressure in the bottom hole space of an underground directional long borehole with reasonable structural design and strong practicability, which can not only quickly plug the small bottom hole space to detect the gas pressure in the bottom hole space, so as to indirectly obtain the gas content of the coal seam; but also realize the multi-point detection of the gas pressure in the bottom hole space of the directional long borehole while drilling, that is, it can obtain the gas content at multiple points.

[0006] To achieve the above purpose, the invention provides the following technical solutions:

[0007] The invention provides a device for measuring the gas pressure in the bottom hole space of an underground directional long borehole while drilling, including a gas pressure detection mechanism, a plugging mechanism and a waterway closing mechanism connected in sequence. The waterway closing mechanism cuts off the waterway and drives the plugging mechanism to plug the bottom hole space and drives the gas pressure detection mechanism to communicate with the bottom hole space to complete the pressure measurement.

[0008] Furthermore, the air pressure detection mechanism includes a first outer tube, an inner tube, an air path closing slider, and a return spring. A fixing position for installing the inner tube and the return spring is provided on the inner wall of the first outer tube, and an air path closing slider acting with the return spring is arranged between the inner tube and the first outer tube; an outer side air guide hole is provided on the first outer tube, a middle air guide hole is provided on the air path closing slider, and an inner side air guide hole corresponding to the outer side air guide hole up and down is provided on the inner tube. The middle air guide hole communicates with the outer side air guide hole when the return spring is compressed, and is misaligned otherwise; a pressure measurement air chamber and a detection hardware chamber are arranged in the inner tube, and the inner side air guide hole communicates with the pressure measurement air chamber.

[0009] Furthermore, a single-chip microcomputer and a battery are electrically connected in the detection hardware chamber, and a pressure sensor and a temperature sensor electrically connected to the single-chip microcomputer are arranged in the pressure measurement air chamber.

[0010] Furthermore, the plugging mechanism includes a second outer tube, a plugging rubber ring, a plugging transmission rod, and a retaining ring. The second outer tube is sequentially connected to the first outer tube. The plugging rubber ring is sleeved on the second outer tube, and one end of the plugging rubber ring is fixed to the second outer tube, and the other end is connected with a retaining ring slidably matched with the second outer tube. The plugging transmission rod is arranged on the central axis of the second outer tube and can act on the air path closing slider arranged on the air pressure detection mechanism, and the retaining ring is fixed on the plugging transmission rod.

[0011] Furthermore, a slideway for the retaining ring to slide is provided on the second outer tube.

[0012] Furthermore, the water path closing mechanism includes a third outer tube, a stop valve, a power transmission rod, a power spring, and a sliding block. The third outer tube is sequentially connected to the second outer tube. The third outer tube is provided with a stop valve and a sliding block which are respectively slidably matched with it. The power transmission rod is arranged on the sliding block and acts on the plugging transmission rod at the end away from the sliding block. A power spring is sleeved on the power transmission rod, and a fixing member for installing the power spring is provided on the third outer tube. The stop valve is arranged on the opposite side of the sliding block with respect to the power transmission rod.

[0013] Furthermore, sliding teeth are provided on the corresponding sides of the stop valve and the sliding block facing each other.

[0014] Furthermore, the power transmission rod and the plugging transmission rod are of an integral structure.

[0015] Furthermore, a slide rail for the sliding block to slide and a limiting block for limiting the stop valve are provided on the inner wall of the third outer tube, and a limiting groove for limiting the sliding block is provided on the slide rail.

[0016] The present invention also provides a measurement method based on the above-mentioned in-well directional long borehole bottom space gas pressure measurement device while drilling, including the following steps:

[0017] S1. Installation preparation: Assemble the air pressure detection mechanism, the plugging mechanism, and the waterway closing mechanism in sequence, and install them between the downhole motor and the non-magnetic drill pipe below, with the air pressure detection mechanism installed close to the downhole motor;

[0018] S2. Directional drilling: Normally construct according to the directional drilling construction process to the designed detection position;

[0019] S3. Measurement while drilling: Stop drilling and continue to inject liquid to discharge the cuttings until the cuttings at the bottom of the hole are completely discharged. Then increase the pump pressure to raise the pressure inside the drill pipe and close the stop valve to cut off the waterway. Wait for the water pressure inside the drill pipe to continue to rise and push the stop valve to advance the power transmission rod and the sliding block. When the sliding block slides out of the slide rail, the sliding between the sliding block and the stop valve is generated by the sliding teeth to axially rotate the power transmission rod. After the sliding block slides into the limit groove, remove the water pressure. At the same time, the power transmission rod advances the plugging transmission rod to make the retaining ring squeeze the plugging rubber ring to form a closed space at the bottom of the hole. The plugging transmission rod advances the air passage closing slider to connect the outer air guide hole, the middle air guide hole, and the inner air guide hole, and thus connect the closed space at the bottom of the hole with the pressure measurement air chamber. Then, the pressure sensor and the temperature sensor measure the gas pressure and gas temperature data in the closed space at the bottom of the hole, and store the collected data in the single-chip microcomputer;

[0020] S4. Continue drilling: After the measurement of the gas pressure at the bottom of the hole at one measuring point is completed, increase the pump pressure to raise the pressure inside the drill pipe and push the stop valve, so that the sliding between the stop valve and the sliding block is generated again to axially rotate the power transmission rod. After the sliding block slides into the slide rail, remove the water pressure. Under the action of the power spring, the power transmission rod advances the sliding block to drive the stop valve to reset, and the power transmission rod drives the plugging transmission rod to stretch the plugging rubber ring to reset. At the same time, the reset spring pushes the air passage closing slider to move to stagger the middle air guide hole to block the pressure measurement air chamber, and continue the drilling construction according to the directional drilling construction process;

[0021] S5. Multi-point measurement: When the drilling is constructed again to the designed detection position, repeat S3 and S4 to achieve continuous multi-point fixed-point detection of the gas pressure at the bottom of the hole;

[0022] S6. After the entire drilling construction is completed, withdraw the drill tool and disassemble the measuring device, and read the measurement data from the single-chip microcomputer to complete the measurement work.

[0023] The beneficial effects of the present invention are as follows: The device for measuring the gas pressure in the bottom hole space of the underground directional long borehole during drilling mentioned in the present invention seals the bottom hole space through the compression deformation of the plugging rubber ring in the plugging mechanism, which can not only realize the measurement of the gas pressure at the bottom of the hole during drilling, that is, it has the function of detecting the gas pressure in the bottom hole space of the directional long borehole during drilling; but also can realize the continuous multi-point fixed-point detection of the gas pressure at the bottom of the hole in the directional long borehole, making up for the technical blank of the gas parameter detection during drilling in the directional long borehole, and has the characteristics of ingenious design, simple structure, and strong practicability.

[0024] Other advantages, objects and features of the present invention will be set forth to some extent in the following description, and to some extent, will be apparent to those skilled in the art based on the study of the following text, or can be learned from the practice of the present invention. The objects and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0026] Figure 1 is a schematic structural diagram of the device for measuring the gas pressure at the bottom of the downhole directional long borehole in the present invention;

[0027] Description of reference numerals: The air pressure detection mechanism 1, the plugging mechanism 2, the waterway closing mechanism 3, the first outer tube 4, the inner tube 5, the air path closing slider 6, the return spring 7, the outer side air guide hole 8, the middle air guide hole 9, the inner side air guide hole 10, the pressure measuring air chamber 11, the detection hardware chamber 12, the single-chip microcomputer 13, the battery 14, the pressure sensor 15, the temperature sensor 16, the second outer tube 17, the plugging rubber ring 18, the plugging transmission rod 19, the slideway 20, the retaining ring 21, the third outer tube 22, the stop valve 23, the power transmission rod 24, the power spring 25, the sliding block 26, the sliding teeth 27, the slide rail 28, the limiting block 29, the limiting groove 30. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present invention will be further described below in conjunction with the specific embodiments. Among them, the accompanying drawings are only for illustrative purposes, showing only schematic diagrams, not physical diagrams, and should not be construed as a limitation of this patent; in order to better illustrate the embodiments of the present invention, some components in the drawings will be omitted, enlarged or reduced, and do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0029] As Figure 1 shown, the device for measuring the gas pressure at the bottom of the downhole directional long borehole mentioned in this embodiment includes an air pressure detection mechanism 1, a plugging mechanism 2 and a waterway closing mechanism 3 connected in sequence. The waterway is cut off by the waterway closing mechanism, and the plugging mechanism is driven to plug the bottom hole space and the air pressure detection mechanism is driven to communicate with the bottom hole space to complete the measurement work.

[0030] Specifically, the air pressure detection mechanism 1 includes a first outer tube 4, an inner tube 5, an air path closing slider 6, and a return spring 7. A fixing position (not marked) for installing the inner tube 5 and the return spring 7 is provided on the inner wall of the first outer tube 4, and an air path closing slider 6 acting with the return spring 7 is arranged between the inner tube 5 and the first outer tube 4. An outer side air guide hole 8 is provided on the first outer tube 4, an intermediate air guide hole 9 is provided on the air path closing slider 6, and an inner side air guide hole 10 corresponding to the outer side air guide hole 8 in the up and down direction is provided on the inner tube 5. When the return spring 7 is compressed, the intermediate air guide hole 9 enables the outer side air guide hole 8 and the inner side air guide hole 10 to communicate. On the contrary, when the return spring 7 is in the natural state, the inner side air guide hole 10 is misaligned to separate the outer side air guide hole 8 and the inner side air guide hole 10. A pressure measurement air chamber 11 and a detection hardware chamber 12 are arranged in the inner tube 5. The inner side air guide hole 10 is communicated with the pressure measurement air chamber 11. A single-chip microcomputer 13 and a battery 14 which are electrically connected are arranged in the detection hardware chamber 12. A pressure sensor 15 and a temperature sensor 16 which are electrically connected to the single-chip microcomputer 13 are arranged on the dividing surface between the pressure measurement air chamber 11 and the detection hardware chamber 12.

[0031] The plugging mechanism 2 includes a second outer tube 17, a plugging rubber ring 18, a plugging transmission rod 19, and a retaining ring 21. The second outer tube 17 is sequentially connected to the first outer tube 4. The plugging rubber ring 18 is sleeved on the second outer tube 17, and one end of the plugging rubber ring 18 is fixed to the second outer tube 17, and the other end is connected with a retaining ring 21 which is slidably matched with the second outer tube 17. The plugging transmission rod 19 is arranged on the central axis of the second outer tube 17 and can act on the air path closing slider 6 arranged on the air pressure detection mechanism 1. The retaining ring 21 is fixed on the plugging transmission rod 19 and can move axially along with the plugging transmission rod. A slideway 20 for the directional sliding of the retaining ring 21 is provided on the second outer tube 17.

[0032] The water path closing mechanism 3 includes a third outer tube 22, a stop valve 23, a power transmission rod 24, a power spring 25, and a sliding block 26. The third outer tube 22 is sequentially connected to the second outer tube 17. A stop valve 23 and a sliding block 26 which are respectively slidably matched with the third outer tube 22 are arranged on the third outer tube 22. The power transmission rod 24 is arranged on the sliding block 26 and acts on the plugging transmission rod 19 at the end away from the sliding block 26. The power spring 25 is sleeved on the power transmission rod 24. A fixing member (not marked) for installing the power spring 25 is provided on the third outer tube 22. The stop valve 23 is arranged on the side opposite to the power transmission rod 24 with respect to the sliding block 26. Sliding teeth 27 are arranged on the corresponding sides of the stop valve 23 and the sliding block 26 facing each other, and the stop valve and the sliding block can be rotated relative to each other by using the sliding teeth. A slide rail 28 for the sliding of the sliding block 26 and the stop valve 23 and a limit block 29 for limiting the stop valve 23 are arranged on the inner wall of the third outer tube 22. A limit groove 30 for limiting the sliding block 26 is arranged on the slide rail 28, and the stop valve 23 is located between the sliding block 26 and the limit block 29.

[0033] In this embodiment, the first outer tube 4, the second outer tube 17 and the third outer tube 22 mentioned above are communicated with each other, and the inner tube 5, the gas path closing slider 6, the sliding block 26, the fixing positions or fixing parts of the installation return spring 7, the plugging transmission rod 19, the power transmission rod 24 and the power spring 25 will not affect the liquid injection work.

[0034] In another embodiment, the power transmission rod 24 and the plugging transmission rod 19 are of an integral structure, but at this time, the plugging transmission rod 19 should be rotationally connected to the retaining ring 21 in the radial direction.

[0035] The following elaborates in detail the method for measuring the gas pressure in the bottom hole space of the downhole directional long borehole with the drill. The steps are as follows:

[0036] Step1. Device installation: Assemble the air pressure detection mechanism 1, the plugging mechanism 2 and the water path closing mechanism 3 in the downhole directional long borehole bottom hole space gas pressure measurement device with the drill in sequence, and install the downhole directional long borehole bottom hole space gas pressure measurement device with the drill between the bottom hole motor (not shown) of the directional drill tool and the lower non-magnetic drill pipe (not shown), and install the air pressure detection mechanism 1 near the bottom hole motor;

[0037] Step2. Normal construction of the directional borehole: Normally construct to the designed detection position according to the directional borehole construction process;

[0038] Step 3. Measurement of gas pressure at the bottom of the hole during drilling: When the construction reaches the designed detection position, stop drilling, continue to inject liquid to discharge slag. After the drill cuttings at the bottom of the hole are discharged completely, increase the pressure of the pump of the directional drilling rig (not shown), so that the pressure inside the drill pipe (not shown) rises. When the water pressure inside the drill pipe reaches a certain value, the stop valve 23 in the waterway closing mechanism 3 closes, cutting off the waterway. The water pressure inside the drill pipe continues to rise, and the water pushes the stop valve 23 to move towards the plugging mechanism 2. During the movement of the stop valve 23, the jacking power transmission rod 24 and the sliding block 26 move along the slide rail 28. When the sliding block 26 slides out of the slide rail 28, sliding occurs between the sliding teeth 27 between the sliding block 26 and the stop valve 23, causing the power transmission rod 24 to rotate axially. After the sliding block 26 slides into the limit groove 30 of the slide rail 28, remove the water pressure. At the same time, during the process of being jacked in, the power transmission rod 24 jacks in the plugging transmission rod 19, so that the retaining ring 21 on the plugging transmission rod 19 squeezes the plugging rubber ring 18, causing the plugging rubber ring 18 to be compressed and deformed, realizing the sealing of the annular space between the second outer pipe 17 of the plugging mechanism 2 and the borehole wall to form a closed space at the bottom of the hole. When the plugging transmission rod 19 is jacked in, the plugging transmission rod 19 jacks in the air path closing slider 6 in the air pressure detection mechanism 1, realizing the sequential connection of the outer side air guide hole 8 of the first outer pipe 4 of the air pressure detection mechanism 1, the middle air guide hole 9 of the air path closing slider 6, and the inner side air guide hole 10 on the inner pipe 5 of the air pressure detection mechanism 1, so as to connect the pressure measurement air chamber 11 in the inner pipe 5 of the air pressure detection mechanism 1 with the closed space at the bottom of the hole. Then, the gas pressure and gas temperature data in the closed space at the bottom of the hole are measured by the pressure sensor 15 and the temperature sensor 16 respectively, and the collected data is stored in the single-chip microcomputer 13;

[0039] Step 4. Continue drilling construction: After the measurement of the gas pressure at the bottom of the hole of one measurement point is completed, increase the pressure of the pump of the directional drilling rig to raise the pressure inside the drill pipe, push the stop valve 23, and the sliding teeth 27 between the stop valve 23 and the sliding block 26 slide again, causing the power transmission rod 24 to rotate axially. After the sliding block 26 slides into the slide rail 28, remove the water pressure. Under the action of the power spring 25, the power transmission rod 24 jacks in the stop valve 23 to make it return to the position of the limit block 29, realizing the reset of the stop valve 23; at the same time, the power transmission rod 24 drives the plugging transmission rod 19 to stretch the plugging rubber ring 18, realizing the reset of the plugging transmission rod 19 and the plugging rubber ring 18; at the same time, the reset spring 7 pushes the air path closing slider 6 to move, realizing the re-sealing of the pressure measurement air chamber 11, and then each mechanism of the device for measuring the gas pressure at the bottom of the long borehole during drilling is reset. And continue the drilling construction according to the directional drilling construction technology again;

[0040] Step 5. Multi-point measurement: When the drilling is constructed again to the designed detection position, repeating Step 3 and Step 4 can realize multi-point continuous measurement;

[0041] Step 6. After the entire drilling construction is completed, withdraw the drill tool, disassemble the device for measuring the gas pressure in the bottom hole space of the downhole directional long borehole while drilling, read the measurement data from the single-chip microcomputer 13, and complete the measurement work.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the present technical solution, and they should all be covered by the scope of the claims of the present invention.

Claims

1. Downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling, characterized in that, It includes a pressure detection mechanism (1), a plugging mechanism (2), and a waterway closing mechanism (3) connected in sequence. The waterway closing mechanism cuts off the waterway and drives the plugging mechanism to plug the bottom hole space and drives the pressure detection mechanism to communicate with the bottom hole space to complete the pressure measurement; The pressure detection mechanism includes a first outer tube (4), an inner tube (5), a gas path closing slider (6), and a return spring (7). Fixed positions for installing the inner tube and the return spring are provided on the inner wall of the first outer tube, and a gas path closing slider acting with the return spring is arranged between the inner tube and the first outer tube. An outer side air guide hole (8) is provided on the first outer tube, an intermediate air guide hole (9) is provided on the gas path closing slider, and an inner side air guide hole (10) corresponding to the outer side air guide hole up and down is provided on the inner tube. The intermediate air guide hole communicates with the outer side air guide hole when the return spring is compressed, and is misaligned otherwise. A pressure measurement gas chamber (11) and a detection hardware chamber (12) are arranged in the inner tube, and the inner side air guide hole communicates with the pressure measurement gas chamber; The plugging mechanism includes a second outer tube (17), a plugging rubber ring (18), a plugging transmission rod (19), and a retaining ring (21). The second outer tube is connected to the first outer tube in sequence. The plugging rubber ring is sleeved on the second outer tube, and one end of the plugging rubber ring is fixed to the second outer tube, and the other end is connected with a retaining ring slidably matched with the second outer tube. The plugging transmission rod is arranged on the central axis of the second outer tube and can act on the gas path closing slider arranged on the pressure detection mechanism, and the retaining ring is fixed on the plugging transmission rod; The waterway closing mechanism includes a third outer tube (22), a stop valve (23), a power transmission rod (24), a power spring (25), and a sliding block (26). The third outer tube is connected to the second outer tube in sequence. The third outer tube is provided with a stop valve and a sliding block that are respectively slidably matched with it. The power transmission rod is arranged on the sliding block and acts on the plugging transmission rod at the end away from the sliding block. A power spring is sleeved on the power transmission rod, and the third outer tube is provided with a fixing part for installing the power spring. The stop valve is arranged on the side opposite to the power transmission rod with respect to the sliding block.

2. The downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling according to claim 1, characterized in that, A single-chip microcomputer (13) and a battery (14) are electrically connected in the detection hardware chamber, and a pressure sensor (15) and a temperature sensor (16) electrically connected to the single-chip microcomputer are arranged in the pressure measurement gas chamber.

3. The downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling according to claim 1, characterized in that, A slideway (20) for the retaining ring to slide is provided on the second outer tube.

4. The downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling according to claim 1, characterized in that, Sliding teeth (27) are provided on the corresponding sides of the stop valve and the sliding block facing each other.

5. The downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling according to claim 1, characterized in that, The power transmission rod and the plugging transmission rod are of an integral structure.

6. The downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling according to claim 1, characterized in that, On the inner wall of the third outer tube, a slide rail (28) for the sliding block to slide and a limiting block (29) for limiting the stop valve are provided, and a limiting groove (30) for limiting the sliding block is provided on the slide rail.

7. A measurement method based on the downhole directional long - borehole bottom - hole space gas pressure measurement device while drilling according to any one of claims 1 - 6, characterized in that, It includes the following steps: S1. Installation preparation: Assemble the pressure detection mechanism, the plugging mechanism, and the waterway closing mechanism in sequence, and install them between the downhole motor and the non-magnetic drill pipe below, and install the pressure detection mechanism close to the downhole motor; S2. Directional drilling: Normally construct according to the directional drilling construction process to the designed detection position; S3. Measurement while drilling: Stop drilling and continue to inject liquid to remove slag until the drill cuttings at the bottom of the hole are completely removed. Then increase the pump pressure to raise the internal pressure of the drill pipe and close the stop valve to cut off the waterway. Wait for the water pressure in the drill pipe to continue to rise and push the stop valve to advance the power transmission rod and the sliding block. When the sliding block slides out of the slide rail, the sliding between the sliding block and the stop valve is generated by the sliding teeth to axially rotate the power transmission rod. After the sliding block slides into the limit groove, remove the water pressure. At the same time, the power transmission rod advances the plugging transmission rod so that the retaining ring squeezes the plugging rubber ring to form a closed space at the bottom of the hole. The plugging transmission rod advances the air path closing slider so that the outer air guide hole, the middle air guide hole, and the inner air guide hole are connected, and thus the closed space at the bottom of the hole is connected to the pressure measuring air chamber. Then, the pressure sensor and the temperature sensor measure the gas pressure and gas temperature data in the closed space at the bottom of the hole, and store the collected data in the single-chip microcomputer; S4. Continue drilling: After the measurement of the gas pressure at the bottom of the hole at one measuring point is completed, increase the pump pressure to raise the internal pressure of the drill pipe and push the stop valve, so that the sliding between the stop valve and the sliding block is generated again to axially rotate the power transmission rod. After the sliding block slides into the slide rail, remove the water pressure. Under the action of the power spring, the power transmission rod advances the sliding block to drive the stop valve to reset, and the power transmission rod drives the plugging transmission rod to stretch the plugging rubber ring to reset. At the same time, the return spring pushes the air path closing slider to move to stagger the middle air guide hole to block the pressure measuring air chamber, and continue the drilling construction according to the directional drilling construction technology; S5. Multi-point measurement: When the drilling is constructed again to the designed detection position, repeat S3 and S4 to achieve multi-point continuous measurement; S6. After the entire drilling construction is completed, withdraw the drill tool and disassemble the measuring device, and read the measurement data from the single-chip microcomputer to complete the measurement work.

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