A test device and method for measuring gas-solid coupling state coal rock strength

Abstract

The present invention discloses a test device and method for measuring the strength of coal and rock in a gas-solid coupling state, comprising a high-pressure gas cylinder, a booster pump, a pressure stabilizing device, a pressure-maintaining drop hammer device, a vacuum pump and a high-pressure hose; the output end of the high-pressure gas cylinder is connected to the booster pump through a high-pressure hose, the output end of the booster pump is connected to the pressure stabilizing device through a high-pressure hose, the output end of the pressure stabilizing device is connected to the input end of the pressure-maintaining drop hammer device through a high-pressure hose, and the output end of the pressure-maintaining drop hammer device is connected to the vacuum pump through a high-pressure hose; the pressure-maintaining drop hammer device comprises an electric control box and a heavy hammer crushing cylinder, the heavy hammer crushing cylinder is fixed at the bottom of the electric control box, and the electric control box and the heavy hammer crushing cylinder are electrically connected; the heavy hammer crushing cylinder comprises an upper cylinder, an intermediate cylinder, a lower cylinder, a magnetic induction cylinder, an electromagnetic suction cup device and a heavy hammer. The present invention solves the problems of low accuracy and low efficiency of the existing manually operated coal and rock strength determination method, is mainly used to test the solidity coefficient of coal and rock mass, and has the advantages of automated testing and pressure-maintaining testing.

Description

Technical Field

[0001] The invention belongs to the technical field of coal and gas outburst prediction index coal-rock strength measurement, and specifically relates to a test device and method for measuring gas-solid coupled coal-rock strength. Background Art

[0002] Coal and gas outburst is one of the major disasters in coal mine safety production. my country's coal mine outburst prevention level has made great progress in recent years, but serious and major gas accidents still occur from time to time, among which coal and gas outburst accidents are frequent, and the proportion of gas accidents is increasing year by year. Coal rock strength is an important indicator for predicting the danger of coal and gas outburst. Accurately measuring its index size is of great significance for predicting and preventing coal and gas outburst accidents.

[0003] At present, the main method for measuring the strength of coal rock is the drop hammer method. The main principle is to measure the weight or volume of coal powder of a specific particle size formed by the impact of a free-falling weight to reflect the strength of the coal rock mass. The existing testing methods and devices are manually operated, with low accuracy and efficiency. They measure the strength of coal rock in a naturally exposed state and cannot reflect the actual strength of deep coal rock in a gas-solid coupling state. In order to measure the strength of coal rock in a gas-solid coupling state, it is urgent to find new testing devices and methods that can realize free-fall hammer testing under pressure. Summary of the invention

[0004] The present invention aims to address the problems of low accuracy and efficiency of existing manually operated coal rock strength measurement methods and the inability of measurement results under exposure conditions to reflect the actual strength of deep coal rock masses in a gas-solid coupling state. It makes up for the deficiencies of the prior art and provides a test device and method for measuring the gas-solid coupling state coal rock strength under a pressure-maintaining state, which is mainly used to test the strength coefficient of coal rock masses and has the advantages of automated testing and pressure-maintaining testing.

[0005] To achieve the above purpose, the present invention adopts the following technical solution.

[0006] The present invention provides a test device for measuring the strength of coal and rock in a gas-solid coupling state, comprising a high-pressure gas cylinder, a booster pump, a pressure stabilizing device, a pressure-maintaining drop hammer device, a vacuum pump and a high-pressure hose; the output end of the high-pressure gas cylinder is connected to the booster pump through a high-pressure hose, the output end of the booster pump is connected to the pressure stabilizing device through a high-pressure hose, the output end of the pressure stabilizing device is connected to the input end of the pressure-maintaining drop hammer device through a high-pressure hose, and the output end of the pressure-maintaining drop hammer device is connected to the vacuum pump through a high-pressure hose; the pressure-maintaining drop hammer device comprises an electric control box and a heavy hammer crushing barrel, the heavy hammer crushing barrel is fixed at the bottom of the electric control box, and the electric control box and the heavy hammer crushing barrel are electrically connected; the heavy hammer crushing barrel comprises an upper barrel The upper cylinder is connected with the middle cylinder, the middle cylinder is connected with the lower cylinder, one end of the magnetic induction cylinder is arranged on the top of the upper cylinder, the magnetic induction cylinder is provided with a cylinder telescopic rod, the cylinder telescopic rod passes through the upper cylinder and enters the middle cylinder, the electromagnetic suction cup device is arranged in the middle cylinder, the lower part of the cylinder telescopic rod is fixedly connected with the electromagnetic suction cup device, and the bottom of the electromagnetic suction cup device is adsorbed and connected with the heavy hammer; the electric control box is electrically connected with the magnetic induction cylinder, the voltage stabilizing device is connected with the lower cylinder of the heavy hammer crushing cylinder through a high-pressure hose, and the lower cylinder of the heavy hammer crushing cylinder is connected with the vacuum pump through a high-pressure hose.

[0007] As a preferred solution of the present invention, a first gate valve is connected to the high-pressure rubber hose between the high-pressure gas cylinder and the boosting pump, a first pressure sensor is connected to the high-pressure rubber hose between the boosting pump and the pressure stabilizing device, and a second gate valve, a second pressure sensor, and a flow sensor are sequentially connected to the high-pressure rubber hose between the pressure stabilizing device and the pressure maintaining drop hammer device.

[0008] As another preferred embodiment of the present invention, a third gate valve is connected to the high-pressure hose between the pressure-maintaining drop hammer device and the vacuum pump, and the first pressure sensor, the second pressure sensor, and the flow sensor are all connected to a data collector, which is connected to a computer.

[0009] As another preferred embodiment of the present invention, the electric control box is provided with an operation panel, which is installed above the front wall of the electric control box, and a control circuit is provided inside the electric control box; the operation panel is provided with a number adjustment key, a control switch and an indicator light, and the number adjustment key, the control switch and the indicator light are all connected to the control circuit, and the number adjustment key is electrically connected to the magnetic induction cylinder inside the heavy hammer crushing barrel through the control circuit; the electric control box is also electrically connected to the booster pump and the vacuum pump respectively through the control circuit.

[0010] As another preferred embodiment of the present invention, a first flange fixedly connected to the magnetic induction cylinder is provided on the top of the upper cylinder, the first flange is connected to the cylinder mouth of the upper cylinder, the magnetic induction cylinder is fixed to the center hole of the first flange, and a cylinder end head is also provided on the magnetic induction cylinder, the cylinder end head is fixedly connected to the center of the first flange, and the cylinder end head and the cylinder telescopic rod are sealed and connected by a combined gasket; a second flange is provided between the upper cylinder and the middle cylinder, the upper cylinder and the middle cylinder are connected by the second flange, and the cylinder telescopic rod of the magnetic induction cylinder enters the middle cylinder through the through hole in the center of the second flange.

[0011] As another preferred embodiment of the present invention, a magnetic conversion control component for controlling whether the electromagnetic suction cup device is magnetic or non-magnetic is provided in the upper cylinder body. The magnetic conversion control component includes a conductive rod, a conductive roller, and a conductive slide. The conductive rods are located on both sides of the cylinder telescopic rod and are symmetrically connected with the center of the cylinder telescopic rod. The ends of the conductive rods on both sides of the cylinder telescopic rod are connected with conductive rollers. Conductive slides that are respectively connected to the two conductive rollers are vertically arranged on the inner wall of the upper cylinder body. The conductive rollers can be slid up and down and connected to the conductive slides by the drive of the cylinder telescopic rod, and the conductive slides are electrically connected to the electrical control box.

[0012] Furthermore, the conductive slideway includes a conductive copper sheet and an organic glass plate groove, the organic glass plate groove is fixed on the inner wall of the upper cylinder, and the conductive copper sheet is fixedly clamped in the organic glass plate groove.

[0013] Furthermore, the electromagnetic chuck device is provided with a universal joint structure, and the setting of the universal joint structure can ensure that when the bottom adsorption surface of the electromagnetic chuck device contacts the weight, the bottom adsorption surface of the electromagnetic chuck device and the top surface of the weight always remain parallel.

[0014] As another preferred embodiment of the present invention, the lower cylinder is a cylinder for placing coal samples, and the lower cylinder includes a coal sample tank and a coal sample mortar. The coal sample mortar is sleeved on the outside of the coal sample tank, and the coal sample mortar is higher than the coal sample tank. A pressure ring is provided at the connection between the lower cylinder and the middle cylinder, and the pressure ring is clamped between the upper port of the coal sample mortar and the middle cylinder to achieve sealing between the middle cylinder and the lower cylinder. The inner diameter of the coal sample mortar corresponds to the outer diameter of the coal sample tank.

[0015] The present invention also provides a test method for measuring the strength of coal and rock in a gas-solid coupling state, which is implemented using the above-mentioned test device for measuring the strength of coal and rock in a gas-solid coupling state, and includes the following steps:

[0016] Step 1, check the air tightness of the gas-solid coupling state coal rock strength test device, the specific steps include: first place the prepared coal sample in the lower cylinder, and then use the pressure ring to achieve sealing; open the first gate valve, fill the high-pressure gas in the high-pressure gas cylinder into the lower cylinder of the pressure-maintaining drop hammer device equipped with the coal sample, and use the booster pump and the pressure stabilizing device to reach the maximum pressure required for the experiment, and close the first gate valve; maintain for more than 6 hours, and observe whether the pressure changes; if there is a change, the test device needs to be tested; if there is no change, use a vacuum pump to degas the lower cylinder and vacuumize it, and then proceed to the next step of the experiment;

[0017] Step 2: Fill the lower cylinder of the pressure-maintaining drop hammer device with the coal sample with methane gas CH4 at a predetermined pressure. The specific steps include: using a vacuum pump to degas the lower cylinder and evacuate it, then opening the first gate valve to charge the cylinder; transmitting the data of the first pressure sensor, the second pressure sensor, and the flow sensor to the computer through a data acquisition device; maintaining the pressure for more than 24 hours to allow the coal sample to fully absorb the gas, recording the final equilibrium pressure, and closing the first gate valve;

[0018] Step three, coal rock strength test, the specific steps include: after the coal sample has reached adsorption equilibrium, operate the operation panel on the electrical control box to perform a drop hammer test to test the strength of the coal rock under predetermined pressure conditions; repeat the above steps one and two to test the strength of the coal rock under different gas pressure conditions.

[0019] Beneficial effects of the present invention:

[0020] Compared with the prior art, the present invention solves the problems of low accuracy and efficiency of the existing manually operated coal rock strength measurement methods, and also solves the problem that the measurement results under exposure conditions cannot reflect the actual strength of deep coal rock mass in the gas-solid coupling state. It is mainly used to test the strength coefficient of coal rock mass, and has the advantages of automated testing and pressure-maintaining testing. When filled with methane gas CH4, the present invention realizes the reciprocating motion of heavy hammer lifting-free falling-lifting of coal samples in a closed environment, realizes the automatic crushing of coal samples at a certain height, and thus realizes the automated testing of the strength coefficient of coal rock mass in a closed aerated environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of a test device for measuring the gas-solid coupled coal and rock strength of the present invention.

[0022] Figure 2 It is a structural schematic diagram of the operation panel of the present invention.

[0023] Figure 3 It is a structural schematic diagram of the heavy hammer crushing cylinder of the present invention.

[0024] Figure 4 It is a structural schematic diagram of the conductive roller of the present invention.

[0025] Figure 5 It is a structural schematic diagram of the conductive slideway of the present invention.

[0026] Figure numerals: 1 is a high-pressure gas cylinder; 2 is a first gate valve; 3 is a booster pump; 4 is a first pressure sensor; 5 is a pressure stabilizing device; 6 is a second gate valve; 7 is a second pressure sensor; 8 is a flow sensor; 9 is a pressure-maintaining drop hammer device; 10 is an electric control box; 11 is a heavy hammer crushing cylinder; 12 is a third gate valve; 13 is a vacuum pump; 14 is a data acquisition device; 15 is a computer; 16 is an operation panel; 161 is an indicator light; 162 is a number adjustment key ; 163 is a control switch; 17 is a magnetic induction cylinder; 18 is a cylinder end; 19 is a first flange; 21 is an upper cylinder; 22 is a cylinder telescopic rod; 23 is a conductive rod; 24 is a second flange; 25 is an electromagnetic suction cup device; 26 is an intermediate cylinder; 27 is a weight; 28 is a pressure ring; 29 is a coal sample mortar; 30 is a coal sample tank; 31 is a conductive roller; 32 is a conductive slide; 321 is a conductive copper sheet; 322 is a plexiglass plate groove. DETAILED DESCRIPTION

[0027] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] Combination Figure 1 , Figure 3As shown, the embodiment of the present invention provides a test device for measuring the strength of coal and rock in a gas-solid coupling state, including a high-pressure gas cylinder 1, a booster pump 3, a pressure stabilizing device 5, a pressure-maintaining drop hammer device 9, a vacuum pump 13 and a high-pressure hose; the output end of the high-pressure gas cylinder 1 is connected to the booster pump 3 through a high-pressure hose, the output end of the booster pump 3 is connected to the pressure stabilizing device 5 through a high-pressure hose, the output end of the pressure stabilizing device 5 is connected to the input end of the pressure-maintaining drop hammer device 9 through a high-pressure hose, and the output end of the pressure-maintaining drop hammer device 9 is connected to the vacuum pump 13 through a high-pressure hose; the pressure-maintaining drop hammer device 9 includes an electric control box 10 and a heavy hammer crushing barrel 11, the heavy hammer crushing barrel 11 passes through the top of the electric control box 10 and is fixed to the bottom of the electric control box 10, and the electric control box 10 and the heavy hammer crushing barrel 11 are electrically connected; the heavy hammer crushing barrel 11 includes an upper cylinder 21 , an intermediate cylinder 26, a lower cylinder, a magnetic induction cylinder 17, an electromagnetic suction cup device 25 and a heavy hammer 27. The upper cylinder 21 is connected to the intermediate cylinder 26, and the intermediate cylinder 26 is connected to the lower cylinder. One end of the magnetic induction cylinder 17 is arranged at the top of the upper cylinder 21. A cylinder telescopic rod 22 is arranged on the magnetic induction cylinder 17. The cylinder telescopic rod 22 passes through the upper cylinder 21 and enters the intermediate cylinder 26. An electromagnetic suction cup device 25 is arranged in the intermediate cylinder 26. The lower part of the cylinder telescopic rod 22 is fixedly connected to the electromagnetic suction cup device 25, and the bottom of the electromagnetic suction cup device 25 is adsorbed and connected to the heavy hammer 27; the electric control box 10 is electrically connected to the magnetic induction cylinder 17, the voltage stabilizing device 5 is connected to the lower cylinder of the heavy hammer crushing cylinder 11 through a high-pressure hose, and the lower cylinder of the heavy hammer crushing cylinder 11 is connected to the vacuum pump 13 through a high-pressure hose.

[0029] A first gate valve 2 is connected to the high-pressure hose between the high-pressure gas cylinder 1 and the booster pump 3, a first pressure sensor 4 is connected to the high-pressure hose between the booster pump 3 and the pressure stabilizing device 5, and a second gate valve 6, a second pressure sensor 7, and a flow sensor 8 are sequentially connected to the high-pressure hose between the pressure stabilizing device 5 and the pressure-maintaining drop hammer device 9; specifically, the first gate valve 2 is used to control the gas circulation in the high-pressure gas cylinder 1, the booster pump 3 can increase the pressure of the gas coming out of the high-pressure gas cylinder 1, and the pressure stabilizing device 5 can stabilize the gas after the pressure is increased to obtain stabilized gas; the second gate valve 6 is used to control whether the gas in the high-pressure hose flows into the lower cylinder body of the heavy hammer crushing cylinder 11 of the pressure-maintaining drop hammer device 9, the first pressure sensor 4 is used to detect the pressure of the gas circulating in the high-pressure hose, the second pressure sensor 7 is used to detect the gas pressure flowing into the lower cylinder body of the heavy hammer crushing cylinder 11 of the pressure-maintaining drop hammer device 9, and the flow sensor 8 is used to detect the gas flow flowing into the lower cylinder body of the heavy hammer crushing cylinder 11 of the pressure-maintaining drop hammer device 9.

[0030] A third gate valve 12 is connected to the high-pressure rubber hose between the pressure-maintaining drop hammer device 9 and the vacuum pump 13. Opening the third gate valve 12 can allow the vacuum pump 13 to extract the gas in the lower cylinder of the heavy hammer crushing cylinder 11 of the pressure-maintaining drop hammer device 9; the signal input end of the data collector 14 is connected to the first pressure sensor 4, the second pressure sensor 7, and the flow sensor 8 through a line, and the signal output end of the data collector 14 is connected to the computer 15 through a line.

[0031] Combination Figures 1 to 3 As shown, the electric control box 10 is provided with an operation panel 16, and the operation panel 16 is installed above the box wall on the front side of the electric control box 10. A control circuit is provided inside the electric control box 10. The control circuit is a conventional circuit, and its circuit connection structure and principle are not described in detail in the embodiment of the present invention; the operation panel 16 is provided with a number adjustment key 162, a control switch 163 and an indicator light 161, the control switch 163 includes an air pump switch, a test switch, and a power switch, and the indicator light 161 includes an air pump display light, an up display light, and a down display light; the power switch is used to control the power on and off of the entire test device, the test switch is used to control the operation of the pressure-maintaining drop hammer device 9, and the number adjustment key 162 is used to set The working times of the pressure-maintaining drop hammer device 9 are determined and adjusted. When the pressure-maintaining drop hammer device 9 is working, the cylinder telescopic rod 22 of the magnetic induction cylinder 17 will move up and down. When it rises, the corresponding rising indicator light will light up, and when it falls, the corresponding falling indicator light will light up, so as to realize the lifting and falling of the heavy hammer 27; the air pump switch is used to control the operation of the vacuum pump 13. When the vacuum pump 13 is working, the air pump indicator light will light up; the number adjustment key 162, the control switch 163 and the indicator light 161 are all connected to the control circuit, and the number adjustment key 162 and the test switch are electrically connected to the magnetic induction cylinder 17 inside the heavy hammer crushing barrel 11 through the control circuit; the electric control box 10 is also electrically connected to the booster pump 3 and the vacuum pump 13 through the control circuit.

[0032] A first flange 19 fixedly connected to the magnetic induction cylinder 17 is provided on the top of the upper cylinder 21. The first flange 19 is connected to the cylinder mouth of the upper cylinder 21, and the connection between the first flange 19 and the upper cylinder 21 is sealed by an O-ring; the magnetic induction cylinder 17 is fixed on the center hole of the first flange 19, and a cylinder head 18 is also provided on the magnetic induction cylinder 17. The cylinder head 18 is fixedly connected to the center of the first flange 19, and the cylinder head 18 and the cylinder telescopic rod 22 are sealed and connected by a combined gasket; a second flange 24 is provided between the upper cylinder 21 and the intermediate cylinder 26, and the upper cylinder 21 and the intermediate cylinder 26 are connected by the second flange 24, and the cylinder telescopic rod 22 of the magnetic induction cylinder 17 enters the intermediate cylinder 26 through the through hole in the center of the second flange 24.

[0033] Combination Figures 3 to 5As shown, a magnetic conversion control component for controlling whether the electromagnetic suction cup device 25 is magnetic or non-magnetic is provided in the upper cylinder 21, and the magnetic conversion control component includes a conductive rod 23, a conductive roller 31, and a conductive slide 32. The conductive rods 23 are located on both sides of the cylinder telescopic rod 22 and are symmetrically connected with the center of the cylinder telescopic rod 22. The ends of the conductive rods 23 on both sides of the cylinder telescopic rod 22 are connected with conductive rollers 31. Conductive slides 32 respectively connected to the two conductive rollers 31 are vertically provided on the inner side wall of the upper cylinder 21. The conductive rollers 31 can be slid up and down by the cylinder telescopic rod 22 and are connected to the conductive slide 32. The conductive slide 32 is electrically connected to the electric control box 10.

[0034] The conductive slide 32 includes a conductive copper sheet 321 and an organic glass plate groove 322. The organic glass plate groove 322 is fixed on the inner wall of the upper cylinder 21, and the conductive copper sheet 321 is fixedly clamped in the organic glass plate groove 322. The length of the conductive copper sheet 321 is less than the length of the organic glass plate groove 322. The lower edge of the conductive copper sheet 321 is aligned with the lower edge of the organic glass plate groove 322, and the upper edge of the conductive copper sheet 321 is lower than the upper edge of the organic glass plate groove 322. In this way, there will be a section of area without the conductive copper sheet 321 at the top of the organic glass plate groove 322.

[0035] The electromagnetic suction cup device 25 is provided with a universal joint structure, which can ensure that when the bottom suction surface of the electromagnetic suction cup device 25 contacts the weight 27, the bottom suction surface of the electromagnetic suction cup device 25 and the top surface of the weight 27 always remain parallel.

[0036] It should be noted that the electromagnetic suction cup device 25 is a prior art. In the embodiment of the present invention, the specific details of the structure of the electromagnetic suction cup device 25 are not described in detail. The electromagnetic suction cup device 25 is turned on and off by the electromagnetic induction coil inside it to achieve the separation and connection of the weight 27. When the electromagnetic suction cup device 25 is powered on, there is magnetic attraction to the weight 27, and when the power is off, there is no magnetism and no effect on the weight 27; the magnetic induction cylinder 17 drives the electromagnetic suction cup device 25 to reciprocate up and down through the cylinder telescopic rod 22, and after the weight 27 is lifted to a fixed height, the conductive roller 31 at the end of the conductive rod 23 connected to the cylinder telescopic rod 22 is located in the top area of ​​the conductive slide 32 without a conductive copper sheet 321. Therefore, the electromagnetic suction cup device 25 is powered off and has no magnetism. The weight 27 falls, and the weight 27 falls freely to crush the coal sample in the coal sample tank 30. Specifically, the magnetic or non-magnetic nature, that is, the magnetic conversion of the electromagnetic suction cup device 25 is achieved by using a magnetic conversion control component, which is composed of a conductive rod 23, a conductive roller 31, and a conductive slide 32. The electromagnetic suction cup device 25, the cylinder telescopic rod 22, the conductive rod 23, the conductive roller 31 and the conductive slide 32 are electrically connected together, and the operating panel 16 on the electrical control box 10 is used to control whether the conductive slide 32 is energized, thereby realizing the electromagnetic magnetic conversion of the electromagnetic suction cup device 25.

[0037] The lower cylinder is a cylinder for placing coal samples, and the lower cylinder includes a coal sample tank 30 and a coal sample mortar 29. The coal sample mortar 29 is sleeved on the outside of the coal sample tank 30, and the coal sample mortar 29 is higher than the coal sample tank 30. A pressure ring 28 is provided at the connection between the lower cylinder and the intermediate cylinder 26. The pressure ring 28 is clamped between the upper end of the coal sample mortar 29 and the intermediate cylinder 26 to achieve sealing between the intermediate cylinder 26 and the lower cylinder. The inner diameter of the coal sample mortar 29 corresponds to the outer diameter of the coal sample tank 30.

[0038] The present invention also provides a test method for measuring the strength of coal and rock in a gas-solid coupling state, which is implemented using the above-mentioned test device for measuring the strength of coal and rock in a gas-solid coupling state, and includes the following steps:

[0039] Step 1, check the air tightness of the gas-solid coupling state coal rock strength test device, the specific steps include: first place the prepared coal sample in the lower cylinder, and then use the pressure ring 28 to achieve sealing; open the first gate valve 2, fill the high-pressure gas in the high-pressure gas cylinder 1 into the lower cylinder of the pressure-maintaining drop hammer device 9 equipped with the coal sample, and use the booster pump 3 and the pressure stabilizing device 5 to reach the maximum pressure required for the experiment, and close the first gate valve 2; maintain for more than 6 hours, and observe whether the pressure changes; if there is a change, the test device needs to be tested; if there is no change, use the vacuum pump 13 to degas and vacuum the lower cylinder, and then proceed to the next step of the experiment;

[0040] Step 2, filling the lower cylinder of the pressure-maintaining drop hammer device 9 with the coal sample with methane gas CH4 of a predetermined pressure, the specific steps include: using the vacuum pump 13 to degas the lower cylinder and evacuate it, then opening the first gate valve 2 to charge; transmitting the data of the first pressure sensor 4, the second pressure sensor 7, and the flow sensor 8 to the computer 15 through the data acquisition device 14; keeping it for more than 24 hours to allow the coal sample to fully absorb the gas, recording the final equilibrium pressure, and closing the first gate valve 2;

[0041] Step three, coal rock strength test, the specific steps include: after the coal sample is adsorbed to equilibrium, operate the operation panel 16 on the electrical control box 10 to perform a drop hammer test to test the coal rock strength under predetermined pressure conditions; repeat the above steps one and two to test the coal rock strength under different gas pressure conditions.

[0042] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. A test device for measuring the strength of coal and rock in a gas-solid coupling state, characterized in that: It includes a high-pressure gas cylinder, a booster pump, a pressure stabilizing device, a pressure-maintaining drop hammer device, a vacuum pump and a high-pressure hose; the output end of the high-pressure gas cylinder is connected to the booster pump through a high-pressure hose, the output end of the booster pump is connected to the pressure stabilizing device through a high-pressure hose, the output end of the pressure stabilizing device is connected to the input end of the pressure-maintaining drop hammer device through a high-pressure hose, and the output end of the pressure-maintaining drop hammer device is connected to the vacuum pump through a high-pressure hose; the pressure-maintaining drop hammer device includes an electric control box and a heavy hammer crushing cylinder, the heavy hammer crushing cylinder is fixed to the bottom of the electric control box, and the electric control box and the heavy hammer crushing cylinder are electrically connected; the heavy hammer crushing cylinder includes an upper cylinder, an intermediate cylinder, a lower cylinder, a magnetic The induction cylinder, the electromagnetic suction cup device and the heavy hammer, the upper cylinder is connected with the middle cylinder, the middle cylinder is connected with the lower cylinder, one end of the magnetic induction cylinder is arranged on the top of the upper cylinder, the magnetic induction cylinder is provided with a cylinder telescopic rod, the cylinder telescopic rod passes through the upper cylinder and enters the middle cylinder, the electromagnetic suction cup device is arranged in the middle cylinder, the lower part of the cylinder telescopic rod is fixedly connected with the electromagnetic suction cup device, and the bottom of the electromagnetic suction cup device is adsorbed and connected with the heavy hammer; the electric control box is electrically connected with the magnetic induction cylinder, the voltage stabilizing device is connected with the lower cylinder of the heavy hammer crushing cylinder through a high-pressure hose, and the lower cylinder of the heavy hammer crushing cylinder is connected with the vacuum pump through a high-pressure hose; A magnetic conversion control component for controlling whether the electromagnetic suction cup device is magnetic or non-magnetic is arranged in the upper cylinder body. The magnetic conversion control component includes a conductive rod, a conductive roller, and a conductive slide. The conductive rods are located on both sides of the cylinder telescopic rod and are symmetrically connected with the center of the cylinder telescopic rod. The ends of the conductive rods on both sides of the cylinder telescopic rod are connected with conductive rollers. Conductive slides that are respectively connected to the two conductive rollers are vertically arranged on the inner wall of the upper cylinder body. The conductive rollers can be slid up and down and connected in the conductive slides by being driven by the cylinder telescopic rod. The conductive slides are electrically connected to the electric control box.

2. The gas-solid coupling state coal-rock strength test device according to claim 1 is characterized by: A first gate valve is connected to the high-pressure rubber hose between the high-pressure gas cylinder and the booster pump, a first pressure sensor is connected to the high-pressure rubber hose between the booster pump and the pressure stabilizing device, and a second gate valve, a second pressure sensor, and a flow sensor are sequentially connected to the high-pressure rubber hose between the pressure stabilizing device and the pressure-maintaining drop hammer device.

3. The gas-solid coupled coal-rock strength test device according to claim 2 is characterized by: A third gate valve is connected to the high-pressure rubber hose between the pressure-maintaining drop hammer device and the vacuum pump. The first pressure sensor, the second pressure sensor, and the flow sensor are all connected to a data collector, and the data collector is connected to a computer.

4. The gas-solid coupled coal-rock strength test device according to claim 1 is characterized by: The electric control box is provided with an operation panel, which is installed above the front wall of the electric control box, and a control circuit is provided inside the electric control box; the operation panel is provided with a number adjustment key, a control switch and an indicator light, and the number adjustment key, the control switch and the indicator light are all connected to the control circuit, and the number adjustment key is electrically connected to the magnetic induction cylinder inside the heavy hammer crushing barrel through the control circuit; the electric control box is also electrically connected to the booster pump and the vacuum pump respectively through the control circuit.

5. The gas-solid coupled coal-rock strength test device according to claim 1 is characterized by: A first flange fixedly connected to the magnetic induction cylinder is arranged on the top of the upper cylinder, the first flange is connected to the cylinder mouth of the upper cylinder, the magnetic induction cylinder is fixed on the center hole of the first flange, a cylinder end head is also arranged on the magnetic induction cylinder, the cylinder end head is fixedly connected to the center of the first flange, and the cylinder end head and the cylinder telescopic rod are sealed and connected by a combined gasket; a second flange is arranged between the upper cylinder and the middle cylinder, the upper cylinder and the middle cylinder are connected by the second flange, and the cylinder telescopic rod of the magnetic induction cylinder enters into the middle cylinder through the through hole in the center of the second flange.

6. The gas-solid coupling state coal-rock strength test device according to claim 1 is characterized by: The conductive slideway comprises a conductive copper sheet and an organic glass plate groove, wherein the organic glass plate groove is fixed on the inner side wall of the upper cylinder body, and the conductive copper sheet is fixedly clamped in the organic glass plate groove.

7. The gas-solid coupled coal-rock strength test device according to claim 1 is characterized by: The lower cylinder is a cylinder for placing coal samples. The lower cylinder includes a coal sample tank and a coal sample mortar. The coal sample mortar is sleeved on the outside of the coal sample tank. The coal sample mortar is higher than the coal sample tank. A pressure ring is provided at the connection between the lower cylinder and the middle cylinder. The pressure ring is clamped between the upper port of the coal sample mortar and the middle cylinder to achieve sealing between the middle cylinder and the lower cylinder. The inner diameter of the coal sample mortar corresponds to the outer diameter of the coal sample tank.

8. A test method for determining the strength of coal and rock in a gas-solid coupling state, characterized in that: The steps include: Step 1, check the air tightness of the gas-solid coupling state coal rock strength test device described in any one of claims 1 to 7, the specific steps include: first place the prepared coal sample in the lower cylinder, and then use the pressure ring to achieve sealing; open the first gate valve, fill the high-pressure gas in the high-pressure gas cylinder into the lower cylinder of the pressure-maintaining drop hammer device equipped with the coal sample, and use the booster pump and the pressure stabilizing device to reach the maximum pressure required for the experiment, and close the first gate valve; maintain for more than 6 hours, and observe whether the pressure changes; if there is a change, the test device needs to be tested; if there is no change, use a vacuum pump to degas the lower cylinder and vacuumize it, and then proceed to the next step of the experiment; Step 2: Fill the lower cylinder of the pressure-maintaining drop hammer device with the coal sample with methane gas CH4 at a predetermined pressure. The specific steps include: using a vacuum pump to degas the lower cylinder and evacuate it, then opening the first gate valve to charge the cylinder; transmitting the data of the first pressure sensor, the second pressure sensor, and the flow sensor to the computer through a data acquisition device; maintaining the pressure for more than 24 hours to allow the coal sample to fully absorb the gas, recording the final equilibrium pressure, and closing the first gate valve; Step three, coal rock strength test, the specific steps include: after the coal sample has reached adsorption equilibrium, operate the operation panel on the electrical control box to perform a drop hammer test to test the coal rock strength under predetermined pressure conditions; repeat the above steps one and two to test the coal rock strength under different gas pressure conditions.

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