Portable detection device for in-situ mechanical strength of coal rock

Abstract

The utility model discloses a coal rock in-situ mechanical strength portable detection device which comprises a box body and a control end flat plate, an electric device, a transmission device, a control system and a drilling parameter monitoring sensor are installed in the box body, a grinding drill bit, a conical drill bit and a rotary cutting drill rod are installed outside the box body, and the control end flat plate is installed on an upper cover of the box body through a buckle. The detection device is easy to operate and convenient to carry, the coal rock mechanical strength can be obtained through automatic calculation and displayed in real time, the manufacturing cost is far lower than that of a traditional large coal rock mechanical strength testing machine, and wide application and popularization in engineering can be achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of in-situ testing in underground coal mines, in particular to a portable detection device for in-situ mechanical strength of coal and rock. Background Art

[0002] As coal mining gradually expands to deeper areas, underground mining technology cannot be implemented smoothly due to space and high ground stress limitations, and it is necessary to detect the mechanical characteristics of coal and rock mass at the mining face in advance to optimize the mining process. The specific functions of determining the mechanical characteristics of coal and rock mass include: ① Evaluating the stability of coal and rock mass to provide safety guarantees for coal mining and other related projects; ② Optimizing coal mining plans to help engineers develop safer and more efficient mining plans; ③ Predicting coal and gas outbursts to provide a basis for engineers' predictions and to develop corresponding preventive measures; ④ Evaluating geological disaster risks to provide data support for the prevention and control of geological disasters.

[0003] At present, the exploration method for the mechanical parameters of coal and rock mass is mainly indoor test measurement, that is, collecting coal and rock samples from the underground mining site, testing them with laboratory equipment, and obtaining the corresponding mechanical parameters. However, this method consumes a lot of manpower and material resources, and has a high time cost.

[0004] How to quickly, conveniently and safely measure the mechanical parameters of coal and rock mass under deep high ground stress conditions is an urgent problem to be solved. Therefore, an in-situ coal and rock testing device and method that is easy to carry and easy to operate is urgently needed, which has important practical significance. Utility Model Content

[0005] In order to solve the above-mentioned problems, the utility model provides a portable detection device for the in-situ mechanical strength of coal and rock. Its purpose is to quickly, portably and safely measure the mechanical parameters of coal and rock masses under the narrow space and high ground stress conditions encountered when mining deep coal resources, thereby providing important parameter basis and theoretical support for coal mining design and construction.

[0006] The specific technical solutions are as follows:

[0007] A portable detection device for the in-situ mechanical strength of coal and rock, comprising a box body and a control end flat plate, wherein an electric device, a transmission device, a control system, and a drilling parameter monitoring sensor are installed in the box body, and a flat drill bit, a conical drill bit, and a rotary cutting drill rod are installed outside the box body, the control end flat plate is installed on the upper cover of the box body by means of a snap, and handles for holding are installed on both sides of the box body; a control switch is installed on the outer shell of the box body, and the upper cover of the box body is detachable.

[0008] The electric device includes an electric motor, a battery box and a power supply pipeline; the battery box is loaded with a storage battery and supplies electric energy to the electric motor through the power supply pipeline;

[0009] The transmission device includes a gearbox and a coupling; the gearbox is connected to the motor through the coupling, the motor provides a power source, and the gearbox can convert the power provided by the motor into a low-speed high-torque rotational force;

[0010] The control device is installed above the motor and connected to the buttons on the outside of the box through wires to start and stop the device;

[0011] The drilling parameter monitoring sensors include torque-speed composite sensors, pressure sensors and displacement sensors. The torque-speed composite sensors and pressure sensors are installed at the output shaft of the gearbox to obtain the torque force and drill rod speed as well as the pressure on the drill bit or drill rod when the device is working. The displacement sensor is installed below the gearbox to obtain the drilling displacement of the device.

[0012] The control end tablet is installed on one side of the upper cover of the box through a buckle. It can automatically obtain the data of the drilling parameter monitoring sensor through a wired method, and compile an algorithm to process the drilling data by itself to form a drilling parameter data set that changes with the drilling depth;

[0013] The utility model also comprises a drill chuck, one end of which is mounted on the lower end of the output shaft of the gear box, and the other end of which is connected with a flat drill bit, a conical drill bit or a rotary cutting drill rod.

[0014] The upper end of the drill chuck is connected to the output shaft of the gearbox, and the lower end is connected to the drill bit or drill rod. The drill bits and drill rods are divided into three categories: ① flat drill bits, ② conical pressure heads, and ③ rotary cut drill rods;

[0015] Preferably, handles are provided on both sides of the box; the upper cover of the box is detachable to facilitate replacement of batteries;

[0016] Preferably, the battery box in the electric device is equipped with a high-efficiency lithium battery, which supports the device to work at high intensity, and is equipped with a backup battery; the battery can be charged on the ground;

[0017] Preferably, the electric device and the transmission device are connected and assembled into a whole through a support frame, and fixed inside the box body through a fixing bolt;

[0018] Preferably, the control terminal tablet has two measurement modes for operation, and the tablet can be detached and charged;

[0019] Preferably, the drill chuck, the drill bit and the drill rod are equipped with a tool kit, which can be used to store relevant disassembly tools and batteries.

[0020] The detection method of a portable detection device for in-situ mechanical strength of coal and rock of the utility model comprises the following steps:

[0021] S1: Select the measurement location of the coal and rock mass to be measured, determine the marking points and assemble the equipment;

[0022] S2: Assemble the ground drill bit, adjust the equipment to align with the mark point to be measured, and grind the coal rock mass to make its surface flat and smooth without obvious bumps, providing the prerequisite for the next operation;

[0023] S3: Replace with a conical pressure head, adjust the device to align with the mark point to be measured, press the device so that the tip of the pressure head is pressed into the surface of the polished coal rock mass, and the tip of the pressure head enters the coal rock mass to a certain depth. The drilling parameter monitoring sensor transmits the measured relevant data to the control end tablet for storage and processing;

[0024] S4: Replace the drill rod with a rotary cutting drill rod, adjust the equipment to align with the mark point to be measured, start the equipment switch, and make the drill rod rotary cut to drill into the coal rock surface at the mark point to a certain depth. The drilling parameter monitoring sensor transmits the measured relevant data to the control end tablet for storage and processing;

[0025] S5: operate the tablet output to obtain relevant physical and mechanical parameters of the coal and rock mass, and record the results;

[0026] S6: Continue drilling with rotary cutting drill pipe to sample and preserve coal and rock mass. The rock samples can be brought back to the laboratory for further testing.

[0027] S7: For the coal rock mass at the same location, repeat the above operation at least 5 times to improve the accuracy of the test.

[0028] Preferably, the drilling rig position can be adjusted by a level meter in S2, S3, and S4.

[0029] Preferably, the S3 and S4 equipment need to perform zeroing operation on the drilling parameter monitoring sensor before drilling;

[0030] Preferably, the drilling speed of the S4 equipment is divided into three gears, and the speed gear is adjusted in different situations;

[0031] Preferably, in S5: a quantitative relationship between the measured parameters and the mechanical parameters of the coal rock mass is established according to the equation, a program is designed to perform calculations, and finally the measured mechanical parameters of the coal rock mass are obtained.

[0032] The beneficial effects of the present invention are as follows: (1) The present invention adopts a special portable detection device and method, which is simple to operate and easy to carry, and can obtain and display the mechanical strength of coal and rock through automatic calculation in real time; (2) The built-in system of the control end tablet of the present invention realizes the in-situ acquisition of the mechanical strength of coal and rock by analyzing and processing the measured parameters, and has the characteristics of high efficiency and portability; (3) The cost of the portable detection device of the present invention is much lower than that of traditional large-scale testing machinery for testing the mechanical strength of coal and rock, and can be widely used and promoted in engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the overall structure of the portable detection device for in-situ mechanical strength of coal and rock of the utility model;

[0034] Figure 2 yes Figure 1 Schematic diagram of the internal structure of the device after dismantling the box and removing the drill bit and drill rod:

[0035] Figure 3 yes Figure 1 Another angle diagram of the internal structure of the device after removing the box and the drill bit and drill rod:

[0036] Figure 4 This is the front view of the utility model of the portable detection device for the in-situ mechanical strength of coal and rock:

[0037] Figure 5 This is the top view of the orthographic projection of the portable detection device for in-situ mechanical strength of coal and rock of the utility model:

[0038] Among them, 1-box, 2-control end plate, 3-control switch, 4-handle, 5-ground drill bit, 6-conical pressure head, 7-rotary cutting drill rod; 8-motor, 9-battery box, 10-gear box, 11-control system, 12-power supply pipeline, 13-fixing bolt, 14-drill chuck, 15-torque and speed composite sensor, 16-pressure sensor, 17-displacement sensor, 18-data transmission line, 19-coupling, 20-support frame. DETAILED DESCRIPTION

[0039] The following is a detailed description of the embodiments of the utility model in conjunction with the accompanying drawings. It should be noted that the utility model can be implemented in a variety of different ways as defined and covered by the claims, and therefore, the embodiments disclosed in the specification should not be regarded as limitations of the utility model, but only as examples of embodiments, the purpose of which is to make the features of the utility model obvious.

[0040] Example:

[0041] like Figure 1-Figure 5 As shown, a portable detection device for in-situ mechanical strength of coal and rock includes a box body and a control end flat plate, an electric device installed in the box body, a transmission device, a control system and a drilling parameter monitoring sensor; the device is also equipped with a drill chuck and a detachable drill bit and drill rod.

[0042] The electric device provides mechanical energy for the transmission device; the transmission device can convert the high-speed rotation force transmitted by the electric device into a low-speed high-torque rotation force; the control system controls the start and shut down of the control device; the drilling parameter monitoring sensor includes a torque-speed composite sensor, a pressure sensor and a displacement sensor: the torque-speed composite sensor and the pressure sensor are installed at the output shaft of the gearbox in the transmission device, and are used to obtain the torque force and drill rod speed of the drill rod when the device is working, as well as the pressure on the drill bit or drill rod; the displacement sensor is installed below the gearbox in the transmission device to obtain the drilling displacement of the device. The drill bit and the drill rod are connected to the transmission device through a drill chuck; the control end tablet can automatically obtain the data of the drilling parameter monitoring sensor through the data transmission line, and compiles the algorithm to process the drilling data by itself to form a drilling parameter data set that changes with the drilling depth; the device is equipped with a drill chuck and a detachable drill bit and drill rod for drilling coal and rock.

[0043] The box 1 is provided with handles 4 for holding on both sides; a control switch 3 can be seen on the outer shell of the box, which is used to control the start and stop of the device. The upper cover of the box 1 is detachable, which is convenient for replacing the battery in the device; the control terminal tablet 2 is installed on the upper cover by snapping, and the data transmission line 18 is inserted into the interface of the control terminal tablet 2 to realize data transmission;

[0044] The drill bit and drill rod include a flat drill bit 5, a conical pressure head 6 and a rotary cutting drill rod 7. The flat drill bit 5 has a height of 20 cm, a grinding disc diameter of 15 cm and a frosted lower surface, so that the surface of the coal and rock mass can be polished flat; the conical pressure head 6 has a height of 15 cm, a diameter of 5 cm, and a tip of the pressure head is a regular triangular pyramid-shaped diamond material; the rotary cutting drill rod 7 has a length of 80 cm, an inner diameter of the drill rod is 5 cm, and the end of the drill rod is a pdc rotary cutting drill bit, which can be used to drill rock samples; for easy replacement, two sets of drill bits and drill rods are equipped and placed in the tool bag.

[0045] The electric device includes an electric motor 8, a battery box 9 and a power supply pipe 12. The matching storage battery is installed in the battery box 9 and the electric motor 8 is powered through the power supply pipe 12.

[0046] The transmission device includes a gearbox 10 and a coupling 19. The gearbox 10 is connected to the motor 8 through the coupling 19. The power from the motor 8 drives the gearbox 10 to work. The gearbox 10 can convert the power provided by the motor 8 into a low-speed high-torque rotational force;

[0047] The drill chuck 14 is installed at the lower end of the output shaft of the gear box 10, and the other end is connected to the drill bit or the drill rod.

[0048] The drilling parameter monitoring sensor includes a torque-speed composite sensor 15, a pressure sensor 16 and a displacement sensor 17; the torque-speed composite sensor 15 and the pressure sensor 16 are installed at the output shaft of the gear box, and are used to obtain the torque force and drill rod speed as well as the pressure on the drill bit or drill rod when the device is working and the drill rod is rotated downward into the coal rock mass; the displacement sensor 17 is installed below the gear box to obtain the drilling displacement of the device. In order to improve the measurement accuracy of the downward displacement of the device, a total of 4 displacement sensors 17 are equipped to accurately measure the drilling depth.

[0049] The control end tablet 2 is mounted on one side of the upper cover of the box body 1 by snapping, and can automatically obtain the data of the drilling parameter monitoring sensor through the data transmission line 18, and compile an algorithm to process the drilling data by itself to form a drilling parameter data set that changes with the drilling depth;

[0050] In order to stabilize the internal structure of the device, the battery box 7 and the gear box 10 are fixed by a support frame 20, the transmission device and the electric device are assembled as a whole and placed inside the box body 1, and fixed in the box body by a fixing bolt 14, and the output shaft of the gear box 10 is placed outside the box body 1 through the bottom circular hole, and the torque and speed composite sensor 15 and the pressure sensor 16 are installed at the output shaft to measure the data of the device during drilling operation.

[0051] According to the data measured by the drilling parameter monitoring sensor, the required coal rock mechanical parameters are directly obtained. The control end flat panel 2 needs to design the program through the model and formula. The specific implementation principle is as follows:

[0052] The conical indenter is selected to be a Bohr regular triangular pyramid indenter:

[0053] Hardness calculation formula:

[0054]

[0055] Where: H is the hardness of the material being tested (unit: GPa), P max is the load when the indenter is pressed into any depth, A(h c ) is the corresponding contact area.

[0056] Elastic modulus calculation formula:

[0057]

[0058] Where: E r is the reduced modulus, E and v are the elastic modulus and Poisson’s ratio of the measured material respectively. i 、v i are the elastic modulus and Poisson's ratio of the indenter, respectively. When the indenter is made of diamond, E i =1140GPa,v i=0.07.

[0059] Among them, the reduced modulus E r for:

[0060]

[0061] Where: Equivalent modulus r It represents the modulus of the interaction between the indenter and the sample material, S is the contact stiffness, A is the contact area, and the β value for the Bohr indenter is 1.034.

[0062] The rotary cutting drill rod end is a PDC drill bit

[0063] Uniaxial compressive strength calculation formula

[0064]

[0065] Where: c It represents the equivalent uniaxial compressive strength of rock; N represents the rotation speed; V represents the drilling speed; M represents the torque; F represents the feed force; μ represents the friction coefficient between the cutting edge of the drill bit and the rock; R represents the inner diameter of the drill bit.

[0066] The detection method of the portable detection device for in-situ mechanical strength of coal and rock of the utility model comprises the following steps:

[0067] S1: Select the measurement location of the coal and rock mass to be measured, determine the marking points and assemble the equipment;

[0068] S2: Assemble the flat drill bit 5, adjust the equipment to align with the mark point to be measured, and grind the coal rock mass to make its surface flat and smooth without obvious bumps, providing the prerequisite for the next operation;

[0069] S3: Replace with a conical pressure head 6, adjust the device to align with the mark point to be measured, press the device so that the tip of the pressure head is pressed into the surface of the polished coal rock mass, and the tip of the pressure head enters the coal rock mass to a certain depth, and the drilling parameter monitoring sensor transmits the measured relevant data to the control end tablet for storage and processing;

[0070] S4: Replace the rotary cutting drill rod 7, adjust the equipment to align with the mark point to be measured, start the equipment switch, so that the drill rod rotary cutting drills into the coal rock body surface at the mark point to a certain depth, and the drilling parameter monitoring sensor transmits the measured relevant data to the control end tablet for storage and processing;

[0071] S5: operate the tablet output to obtain relevant physical and mechanical parameters of the coal and rock mass, and record the results;

[0072] S6: Continue drilling using the rotary cutting drill rod 7 to sample and preserve the coal and rock mass, and bring the rock samples back to the laboratory for further testing;

[0073] S7: For the coal rock mass at the same location, repeat the above operation at least 5 times to improve the accuracy of the test.

[0074] Preferably, in S2, S3, and S4, the drilling rig orientation can be adjusted by a level; the drilling parameter monitoring sensor of the S3 and S4 equipment needs to be zeroed before drilling; the drilling speed of the S4 equipment is divided into three gears, and the speed gear is adjusted in different situations; in S5: a quantitative relationship between the measured parameters and the mechanical parameters of the coal rock mass is established according to the equation, and a design program is used for calculation, and finally the measured mechanical parameters of the coal rock mass are obtained and displayed on a flat-panel display screen.

[0075] By using the in-situ mechanical strength identification device for rock mass based on drilling resistance of the utility model, the hardness and elastic modulus of the measured coal rock mass can be obtained by acquiring the thrust exerted on the conical pressure head during the drilling process of the equipment and the drilling displacement; the uniaxial compressive strength of the coal rock mass can be obtained by acquiring parameters such as torque, rotation speed, thrust, etc. during the drilling process when the equipment uses a rotary cutting drill rod; the data measured by the drilling parameter monitoring sensor is stored and transmitted to the control end tablet for data processing, analysis and calculation; the operation is simple and easy to carry, and the limitations of the traditional method for determining the parameters of the coal rock mass and the complex testing method are overcome, and the relevant physical and mechanical parameters of the required coal rock mass can be obtained efficiently and conveniently.

[0076] Finally, it should be noted that the above-described embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A portable detection device for in-situ mechanical strength of coal and rock, comprising a housing (1) and a control end flat panel (2), characterized in that: An electric device, a transmission device, a control system, and a drilling parameter monitoring sensor are installed in the box (1); a flat drill bit (5), a conical drill bit (6), and a rotary cutting drill rod (7) are installed outside the box (1); the control end plate (2) is installed on the upper cover of the box (1) by means of a buckle; handles (4) for holding are respectively installed on both sides of the box (1); a control switch (3) is installed on the outer shell of the box; and the upper cover of the box (1) is detachable.

2. A portable detection device for in-situ mechanical strength of coal and rock according to claim 1, characterized in that: The electric device comprises an electric motor (8), a battery box (9) and a power supply pipeline (12); a storage battery is installed in the battery box (9), and the electric motor (8) is supplied with energy through the power supply pipeline (12).

3. A portable coal rock in-situ mechanical strength detection device according to claim 2, characterized in that: The transmission device comprises a gear box (10) and a coupling (19); the gear box (10) is connected to the motor (8) via the coupling (19), thereby driving the gear box (10) to work; the gear box (10) converts the power provided by the motor (8) into a low-speed high-torque rotational force.

4. A portable coal rock in-situ mechanical strength detection device according to claim 3, characterized in that: The drilling parameter monitoring sensor comprises a torque-speed composite sensor (15), a pressure sensor (16) and a displacement sensor (17); the torque-speed composite sensor (15) and the pressure sensor (16) are installed at the output shaft of the gear box (10); and the displacement sensor (17) is installed below the gear box (10) to obtain the drilling displacement of the device.

5. A portable coal rock in-situ mechanical strength detection device according to claim 4, characterized in that: The control end tablet (2) acquires data from the drilling parameter monitoring sensor via a data transmission line (18), and the data transmission line (18) realizes data transmission by being inserted into an interface of the control end tablet (2).

6. A portable coal rock in-situ mechanical strength detection device according to claim 3, characterized in that: It also comprises a drill chuck (14), one end of which is mounted on the lower end of the output shaft of the gear box (10), and the other end of which is connected to the flat drill bit (5), the conical drill bit (6) or the rotary cutting drill rod (7).

7. A portable coal rock in-situ mechanical strength detection device according to claim 3, characterized in that: The battery box (9) and the gear box (10) are fixed via a support frame (20), and the transmission device and the electric device are fixed in the box body via a fixing bolt (13).

Images