One-hole multi-purpose monitoring device and use method

Abstract

The invention relates to the field of gas extraction, in particular to a one-hole multi-purpose monitoring device and a using method. According to the one-hole multi-purpose monitoring device and the using method, the change conditions of coal seam stress and gas pressure are monitored at the same time through the effect detection hole near the hydraulic coal flushing hole, the inspection of the hydraulic coal flushing pressure relief and permeability increasing effect under the stress-seepage coupling effect is achieved, and meanwhile the consistency of stress and gas pressure data in space is guaranteed. A one-hole multi-purpose monitoring device comprises a drill hole stress monitoring device, a gas pressure monitoring device and a hole sealing assembly. By calculating the position of the fracture line of the key block B and judging the critical minimum value of the width of the reserved coal pillar, when the fracture position is located above the coal pillar and the key block B sinks stably, a small part of the load above the key block B is borne by the coal pillar, a large part of the load is borne by goaf gangue, and at the moment, the influence on the gob-side roadway is minimum; the integrity of the coal pillar close to one side of the roadway is well maintained, and roadway supporting is better facilitated.

Description

Technical Field

[0001] The present invention relates to the field of gas extraction, and in particular to a one-hole multi-purpose monitoring device and a use method thereof. Background Art

[0002] In order to eliminate the danger of coal and gas outburst disasters, it is necessary to extract gas from the outburst coal seams. However, due to the common characteristics of high ground stress, high gas pressure and low permeability in my country's coal seams, the extraction effect is not ideal, making the prevention and control of coal and gas outbursts more severe. In recent years, hydraulic coal flushing pressure relief and permeability enhancement technology has been continuously developed. Practice has shown that hydraulic coal flushing is a highly targeted and effective permeability enhancement and extraction technology, and has also been widely promoted and applied in mining areas. Hydraulic coal flushing technology is a comprehensive hydraulic measure of hydraulic drilling, hydraulic coal flushing and hydraulic wetting to reduce coal seam ground stress, increase coal seam permeability and accelerate gas extraction.

[0003] At present, the main method for testing the effect of hydraulic coal flushing is to monitor the change of gas pressure. However, the main permeability enhancement mechanism of hydraulic coal flushing technology is pressure relief. Therefore, it is very important to investigate the pressure relief and permeability enhancement effect of hydraulic coal flushing drilling under stress-seepage coupling and analyze the changes in coal body stress around the coal flushing hole to test the effect of coal flushing. Summary of the invention

[0004] In order to overcome the problems of the prior art, the present invention provides a one-hole multi-purpose monitoring device and a method of use, which simultaneously monitors the changes in coal seam stress and gas pressure in an effective inspection hole near the hydraulic coal flushing hole, thereby realizing the inspection of the pressure relief and permeability enhancement effect of hydraulic coal flushing under the stress-seepage coupling effect, and at the same time ensuring the consistency of stress and gas pressure data in space.

[0005] The technical solution of the present invention is: a one-hole multi-purpose monitoring device, comprising a drilling stress monitoring device, a gas pressure monitoring device and a hole sealing component.

[0006] The drilling stress monitoring device comprises a drilling dynamometer, an oil pipe, a push rod, a three-way valve, a hydraulic pump, a pressure sensor, a data collector and a data receiver; the drilling dynamometer is connected to the hydraulic pump through the oil pipe and the three-way valve, and the oil bag of the drilling dynamometer is expanded and fixed in the borehole by injecting oil through the hydraulic pump. The drilling dynamometer is composed of two upper and lower clamping plates, and the strain measurement technology is used in the middle to measure the vertical load stress of the coal body. The coal body or rock body around the borehole is damaged and deformed by the stress, and the stress is transmitted to the strain body to generate lateral deformation. The sensor converts the deformation into a current signal, which is converted into a digital signal output through a transmitter circuit and uploaded to a data receiving platform through a data collector and a data receiver.

[0007] The gas pressure monitoring device comprises a gas pressure gauge, a four-way iron pipe, a pressure transmitter and a three-way valve.

[0008] The sealing component comprises a grouting pipeline, a grouting pipeline, a bladder bag, and a quick-setting expansion sealing agent slurry.

[0009] A method for using a one-hole multi-purpose monitoring device includes the following steps: Step A: drilling to form an inspection hole, placing a drilling dynamometer into the inspection hole, inserting a first push rod cross fork into the cross fork at the rear of the drilling dynamometer, and slowly pushing the drilling dynamometer inward without rotating the direction, keeping the drilling dynamometer vertically upward, and gradually straightening the oil pipe (pull the oil pipe slightly to push the oil pipe and the push rod synchronously and smoothly into the hole);

[0010] After the first push rod is sent to the bottom, connect the second push rod, fix it with M5 bolts, and keep the drilling dynamometer vertically upward; all push rods are installed according to the above connection method until the drilling dynamometer is installed to the predetermined position; connect the refueling interface, oil pipe plug and sensor connector;

[0011] Connect the refueling interface to the manual pump, loosen the ejector pin 2 turns, start pressurizing until the stress sensor displays an initial pressure of 5Mpa, continue pressurizing to 5Mpa after the pressure drops, repeat 3 times, and finally fix the initial pressure displayed by the sensor at 5Mpa; quickly tighten the ejector pin, disconnect the refueling interface, put on the sealing sleeve, and pull out the push rod; finally, use the data collector to clear the data stored in the sensor;

[0012] Step B: After the stress monitoring device is installed, the length of the four-part iron pipe and the hole sealer to be sent into the hole is determined according to the drilling depth, and the sending length is 2m from the coal point; the hole is sealed by a two-blocking and one-injection sealing process, and the hole sealer is connected in multiple sections according to the drilling depth; the hole sealer and the four-part iron pipe are tied with steel wire and sent into the efficiency inspection hole, wherein the front end of the four-part iron pipe is connected to the four-part flower pipe, and the flower pipe is wrapped with anti-blocking gauze on all sides; after the above-mentioned hole sealing device is sent into the water-injected borehole, the hole mouth is sealed with quick-drying cement, and normal slurry is prepared and injected into the borehole under pressure through the hole sealer; after the hole sealing is completed, the outer end of the four-part iron pipe is connected to a pressure test gauge, and control valves are provided at both ends of the test gauge.

[0013] Beneficial effects: 1. The outer side of the drilling dynamometer is an expandable oil bag. After the drilling dynamometer is sent into the coal seam, oil can be injected into it through an oil pipe connected to an oil pressure pump to make it expand, so that the drilling dynamometer is fixed on the hole wall. The inner side of the drilling dynamometer is composed of two upper and lower clamps. Strain measurement technology is used in the middle of the clamp to measure the vertical load stress of the coal body. The coal body or rock body around the borehole is damaged and deformed by stress, and the stress is transferred to the strain body to produce lateral deformation. The sensor converts the deformation into a current signal, which is converted into a digital signal output through a transmitter circuit and uploaded to the data receiving platform through a data collector and a data receiver.

[0014] 2. Borehole stress sensors are mainly used to measure changes in coal seam stress fields caused by hydraulic coal flushing. The borehole stress sensor automatically records and stores borehole stress every 5 minutes, and can store stress data for up to 10 days, which can complete real-time monitoring of changes in underground coal seam stress fields. Data acquisition and clearing can be achieved by matching the corresponding stress sensor with a data collector. Data acquisition uses wireless communication, which greatly simplifies the data acquisition process.

[0015] 3. The use of a multi-purpose monitoring device for hydraulic flushing stress and gas pressure in high-gas coal seams can simultaneously monitor the changing patterns of stress and gas pressure in the same inspection hole. This not only avoids the problem of repeated drilling and sealing in traditional detection methods, but also ensures the spatial consistency of stress and gas pressure data. It is of great significance to analyze the influence of coal seam stress on gas permeability and further explore the mechanism of coal seam pressure relief and permeability enhancement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention;

[0017] The markings in the figure are: 1-four-part flower pipe; 2-four-part iron pipe; 3-gas pressure detector; 4-pressure transmitter; 5-stress sensor; 6-stress detector; 7-oil pressure pump. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments, but the protection scope and application scope of the present invention are not limited.

[0019] like Figure 1 As shown, a one-hole multi-purpose monitoring device includes a borehole stress monitoring device, a gas pressure monitoring device and a sealing assembly. The borehole stress monitoring device includes a borehole dynamometer, an oil pipe, a push rod, a three-way valve, an oil pressure pump 7, a pressure sensor, a data collector and a data receiver; the borehole dynamometer is connected to the oil pressure pump 7 through the oil pipe and the three-way valve, and the oil bag of the borehole dynamometer is expanded and fixed in the borehole by oil injection of the oil pressure pump 7. The borehole dynamometer is composed of two upper and lower clamping plates, and the strain measurement technology is used in the middle to measure the vertical load stress of the coal body. The coal body or rock body around the borehole is damaged and deformed by the stress, and the stress is transmitted to the strain body to produce lateral deformation. The sensor converts the deformation into a current signal, which is converted into a digital signal output through the transmitter circuit, and uploaded to the data receiving platform through the data collector and the data receiver. The gas pressure monitoring device includes a gas pressure gauge, a four-way iron pipe 2, a pressure transmitter 4, and a three-way valve. The sealing component comprises a grouting pipeline, a grouting pipeline, a bladder bag, and a quick-setting expansion sealing agent slurry.

[0020] Step A: Drill a hole to form an inspection hole, put the drilling dynamometer into the inspection hole, insert the first push rod cross fork into the cross fork at the rear of the drilling dynamometer, and slowly push the drilling dynamometer inward without turning the direction. Keep the drilling dynamometer vertically upward, and gradually straighten the oil pipe (pull the oil pipe slightly to push the oil pipe and the push rod into the hole synchronously and smoothly); after the first push rod is sent to the bottom, connect the second push rod, fix it with M5 bolts, and keep the drilling dynamometer vertically upward; all push rods are pressed Install the above connection method until the drilling dynamometer is installed to the predetermined position; connect the refueling interface, oil pipe plug and sensor connector; connect the refueling interface to the manual pump, loosen the ejector pin 2 turns, start pressurizing until the stress sensor 5 displays an initial pressure of 5Mpa, continue pressurizing to 5Mpa after the pressure decreases, repeat 3 times, and finally fix the initial pressure displayed by the sensor at 5Mpa; quickly tighten the ejector pin, disconnect the refueling interface, put on the sealing sleeve, and pull out the push rod; finally, use the data collector to clear the data stored in the sensor;

[0021] Step B: After the stress monitoring device is installed, the length of the four-part iron pipe 2 and the sealer sent into the hole is determined according to the drilling depth, and the length is 2m away from the coal point; the sealing process of two blocking and one injection is used to seal the hole, and the sealer is connected in multiple sections according to the drilling depth; the sealer and the four-part iron pipe 2 are tied with steel wire and sent into the efficiency inspection hole, wherein the front end of the four-part iron pipe 2 is connected to the four-part flower pipe 1, and the flower pipe is wrapped with anti-blocking gauze around; after the above-mentioned sealing device is sent into the water-injected borehole, the hole mouth is sealed with quick-drying cement, and normal slurry is prepared and injected into the borehole under pressure through the sealer; after the sealing is completed, the outer end of the four-part iron pipe 2 is connected to a pressure test gauge, and control valves are provided at both ends of the test gauge.

[0022] The above description of the disclosed embodiments enables those skilled in the art to implement and use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit and scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest range consistent with the principles and novel features disclosed herein.

Claims

1. A one-hole multi-purpose monitoring device, characterized in that: It includes a drilling stress monitoring device, a gas pressure monitoring device and a sealing component.

2. A one-hole multi-purpose monitoring device as claimed in claim 1, characterized in that: The drilling stress monitoring device comprises a drilling dynamometer, an oil pipe, a push rod, a three-way valve, an oil pressure pump (7), a pressure sensor, a data acquisition device and a data receiver; the drilling dynamometer is connected to the oil pressure pump (7) through the oil pipe and the three-way valve, and the oil bag of the drilling dynamometer is expanded and fixed in the borehole by injecting oil through the oil pressure pump (7); the drilling dynamometer is composed of two upper and lower clamping plates, and the strain measurement technology is adopted in the middle to measure the vertical load stress of the coal body; the coal body or rock body around the borehole is damaged and deformed by the stress, and the stress is transmitted to the strain body to generate lateral deformation; the sensor converts the deformation into a current signal, which is converted into a digital signal output through a transmitter circuit, and uploaded to a data receiving platform through the data acquisition device and the data receiver.

3. A one-hole multi-purpose monitoring device as claimed in claim 1, characterized in that: The gas pressure monitoring device comprises a gas pressure gauge, a four-way iron pipe (2), a pressure transmitter (4), and a three-way valve.

4. A one-hole multi-purpose monitoring device as claimed in claim 1, characterized in that: The sealing component comprises a grouting pipeline, a grouting pipeline, a bladder bag, and a quick-setting expansion sealing agent slurry.

5. A method for using a one-hole multi-purpose monitoring device as claimed in any one of claims 1 to 4, characterized in that: The following steps are included: Step A: Drill a hole to form an inspection hole, put the drilling dynamometer into the inspection hole, insert the first push rod cross fork into the cross fork at the rear of the drilling dynamometer, and slowly push the drilling dynamometer inward without turning it. Keep the drilling dynamometer vertically upward, and gradually straighten the oil pipe; After the first push rod is sent to the bottom, connect the second push rod, fix it with M5 bolts, and keep the drilling dynamometer vertically upward; all push rods are installed according to the above connection method until the drilling dynamometer is installed to the predetermined position; connect the refueling interface, oil pipe plug and sensor connector; Connect the refueling interface to the manual pump, loosen the ejector pin 2 turns, start pressurizing until the stress sensor (5) displays an initial pressure of 5Mpa, continue pressurizing to 5Mpa after the pressure decreases, repeat 3 times, and finally fix the initial pressure displayed by the sensor at 5Mpa; quickly tighten the ejector pin, disconnect the refueling interface, put on the sealing sleeve, and pull out the push rod; finally, use the data collector to clear the data stored in the sensor; Step B: After the stress monitoring device is installed, the length of the four-part iron pipe (2) and the hole sealer to be sent into the hole is determined according to the drilling depth, and the distance of the sent length to the coal point is 2m; the hole is sealed by adopting a two-blocking and one-injection sealing process, and the hole sealer is connected in multiple sections according to the drilling depth; the hole sealer and the four-part iron pipe (2) are tied with steel wire and sent into the efficiency inspection hole, wherein the front end of the four-part iron pipe (2) is connected to the four-part flower pipe (1), and the four sides of the flower pipe are wrapped with anti-blocking gauze; after the above-mentioned hole sealing device is sent into the water injection borehole, the hole mouth is sealed with quick-drying cement, and normal slurry is prepared and injected into the borehole under pressure through the hole sealer; after the hole sealing is completed, the outer end of the four-part iron pipe (2) is connected to a pressure detection gauge, and control valves are provided at both ends of the detection gauge.

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