A cutting performance test experimental system
By designing a cutting performance test experimental system, the mechanical behavior of the tooth cutting under different parameters is simulated, and the problems of coal mining efficiency and economic benefits caused by cutting tooth wear are solved, and the effect of coal rock boundary identification and coal rock cutting of different hardness is achieved.
Patent Information
- Application Number
- CN201911296075.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2019-12-16
- Publication Date
- 2025-06-10
- Estimated Expiration
- 2039-12-16
AI Technical Summary
The cutting teeth suffers a lot of wear during coal mining, resulting in a decrease in coal mining efficiency and economic benefits. It is difficult for the existing technology to effectively simulate and test the cutting teeth mechanical behavior under different parameters.
A cutting performance testing experimental system is designed, which consists of a movable experimental bench, simulated coal rock unit, ore pressure adjustment device, hydraulic pump and data acquisition device. It can simulate the coal rock cutting process under different cutting teeth, wedge angles, traction speeds and ore pressures, and measure the cutting force simultaneously.
The real simulated tooth cutting process is realized, and different tooth cutting experiments can be carried out, the wedge angle, traction speed and ore pressure of the tooth cutting are adjusted, and coal rock of different hardness is cut. By analyzing the changes in tooth cutting force, the coal rock boundary is identified, which solves the technical problem of coal rock boundary identification and is economical.
Smart Images
Figure CN110987640B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of underground mining equipment, in particular to a cutting performance test experimental system. Background Art
[0002] Coal is the basic resource and energy in China. In 2018, China's coal output was 3.683 billion tons, accounting for about 70% of the total primary energy production; the proportion of China's coal consumption in primary energy consumption was 65%, and coal is still an important guarantee for the development of the national economy. According to expert predictions, the coal production capacity in 2050 will be 350,000 tons, while the demand will be 350,000 - 400,000 tons. China has entered the stage of the middle-income "trap", the proportion of the working-age population will gradually decline, the labor cost will rise rapidly, and the demographic dividend will weaken. With the improvement of people's living standards, the willingness to engage in high-risk and high-intensity physical labor has decreased, and people generally have a strong demand to improve the labor intensity and working environment. There are five major natural disasters in the fully mechanized coal mining face, namely "water, fire, gas, coal dust, and roof", which constantly threaten the lives and occupational health of workers. Therefore, liberating coal miners from the dangerous, harsh, and noisy working environment and replacing workers with equipment for coal mining, directly reducing the number of personnel in the coal mining face is an important means to reduce casualties and ensure safety, and it is also an urgent need for coal mine safety production. The reliable operation of underground coal mining equipment is one of the basic guarantees for intelligent coal mining. As the part of the shearer that directly contacts the coal and rock, the force-bearing situation of the pick directly determines the reliable performance of the shearer. Due to contact friction, the pick is severely worn during the working process, especially when the pick contacts the rock, its wear intensifies. Replacing the pick not only increases the equipment cost of coal mining, but also reduces the efficiency of coal mining. Therefore, the wear of the pick will seriously reduce the economic benefits of coal mining. The wear of the pick is closely related to its own force-bearing. There are significant differences in the force-bearing situations of the pick under different traction speeds, different mine pressures, different coal and rock hardnesses, and different wedge angles. Therefore, it is very necessary to study the mechanical behavior of the pick under different parameters. Summary of the Invention
[0003] The purpose of the present invention is to provide a cutting performance test experimental system, which can simulate the process of the pick cutting coal and rock, realize the coal and rock cutting under different picks, different wedge angles, different cutting speeds, and different mine pressures, and synchronously measure the cutting force.
[0004] The technical solution adopted by the present invention to solve its technical problems is: a cutting performance test experimental system, which consists of the following components: a movable experimental bench, a simulated coal and rock unit, a fixed frame, a mine pressure adjustment device, a piston, a hydraulic pump, a hydraulic cylinder, and a data acquisition device. The cutting device is installed above the movable experimental bench, the simulated coal and rock is installed inside the simulated coal wall fixing frame, the mine pressure adjustment device is connected to the simulated coal wall fixing frame through a threaded connection, and the piston is hinged to the simulated coal wall fixing frame.
[0005] The simulated coal-rock unit consists of simulated coal-rock, two side plates of the coal-rock frame, and the bottom plate of the coal-rock frame. The two side plates of the coal-rock frame are perpendicularly connected to the bottom plate of the coal-rock frame respectively by welding. The simulated coal-rock is a cuboid, which is placed in the cuboid open frame composed of two side plates of the coal-rock frame and the bottom plate of the coal-rock frame.
[0006] The movable experimental bench consists of a frame body, slide rails, a cutting device, lock nuts, and bolts. There are two inverted T-shaped structures at the bottom of the frame body, and the two inverted T-shaped structures are symmetrically distributed. The cross-section of the slide rail has two inverted T-shaped grooves, and the two inverted T-shaped structures are symmetrically distributed. The inverted T-shaped structure at the bottom of the movable experimental bench is installed in the inverted T of the slide rail and slides along the direction perpendicular to the inverted T-shaped groove. There is a U-shaped hole at the bottom of the movable experimental bench in the direction perpendicular to the inverted T-shaped structure for installing and removing bolts.
[0007] The pick holder is cylindrical in shape. The axes of the four pick seats are inclined to the axis of the pick holder and are installed on the cylindrical outer surface of the pick holder, evenly distributed around the circumference, but with different inclination angles. The connection method between the pick seat and the pick holder is welding. The picks of the pick holder and the force measuring sensors are installed in the pick seats.
[0008] The cutting device includes a pick holder and several force measuring units. The force measuring unit consists of a pick seat, a force measuring sensor, a pick, and a pick mounting sleeve. Each force measuring unit forms a different angle with the axis of the pick holder. Therefore, when the pick holder rotates a certain angle, other force measuring units can be used to cut the coal-rock, and the angle between the pick on this force measuring unit and the wedged coal-rock changes. Thus, cutting experiments on coal-rock with different pick wedging angles are carried out.
[0009] The cutting device is installed above the movable experimental bench. The lower surface of the movable experimental bench has a stepped through-hole structure, and the center of the pick holder has a through-hole structure. Bolts pass through the stepped through-holes on the lower surface of the movable experimental bench and the through-holes in the center of the pick holder to connect the movable experimental bench and the pick holder together, and are locked by lock nuts at the same time. When it is necessary to test picks with different wedging angles, loosen the lock nuts to rotate the pick holder by a certain angle, and then the picks with another wedging angle cut the coal-rock.
[0010] The hydraulic cylinder is hinged to the side of the movable experimental bench. When the piston of the hydraulic cylinder expands and contracts, it pushes the hydraulic cylinder to move, causing the movable experimental bench to slide along the inverted T-shaped groove. By controlling the flow rate of the hydraulic cylinder, the moving speed of the movable experimental bench can be controlled, so as to simulate different traction speeds.
[0011] When the movable test bench slides along the inverted T-shaped groove, it drives the cutting device to move horizontally. When the cutting teeth move to the simulated coal and rock, the cutting teeth start to cut the coal and rock. The force sensor in the cutting tooth seat is subjected to an external force, and the test data is input into the data acquisition system to complete a cutting performance test. At the same time, this experimental system can simulate coal and rock with different hardness by replacing the movable coal wall.
[0012] The mine pressure adjustment device includes a pressure regulating movable plate, a pressure regulating wrench, a pressure regulating screw, a pressure regulating connecting rod one, a pressure regulating connecting rod two, a pressure regulating connecting rod three, a pressure regulating connecting rod four, a pressure regulating connecting rod five, a pressure regulating connecting rod six, a side fixing plate, a bolt one, and a nut. The side fixing plate is installed on the outside of the fixed frame, contacts the side plate surface of the fixed frame, and is connected by several bolts and positioned by pins. The side fixing plate is in the shape of a cuboid with a threaded hole in the middle. The pressure regulating screw is screwed into the threaded hole of the side fixing plate. The pressure regulating wrench is of a cylindrical structure. The pressure regulating screw is of a cylindrical shape with an external thread in the middle. There is a cylindrical hole on the outer cylindrical surface of one side, and the axis of this hole is perpendicular to the axis of the pressure regulating screw. The pressure regulating wrench is installed in the cylindrical hole of the pressure regulating screw. When the pressure regulating wrench is rotated, the pressure regulating screw moves horizontally along its own axis. The pressure regulating screw is connected to the pressure regulating connecting rod six by a thread. The other ends of the pressure regulating connecting rod six are respectively hinged to the pressure regulating connecting rod one, the pressure regulating connecting rod three, and the pressure regulating connecting rod two. One side of the pressure regulating connecting rod three is hinged to the pressure regulating connecting rod one and the pressure regulating connecting rod two, and the other side is hinged to the pressure regulating connecting rod four and the pressure regulating connecting rod five. The pressure regulating connecting rod one, the pressure regulating connecting rod two, the pressure regulating connecting rod three, the pressure regulating connecting rod four, and the pressure regulating connecting rod five are all in the shape of a cylinder. The pressure regulating connecting rod two and the pressure regulating connecting rod four are connected to the pressure regulating movable plate. When the pressure regulating screw rotates, the pressure regulating movable plate moves downward, changing the pressure on the coal wall, so as to simulate different mine pressures.
[0013] The simulated coal wall fixed frame is a welded structure, including two left side plates of the fixed frame, a right side plate of the fixed frame, a bottom plate of the fixed frame, a top plate of the fixed frame, and a back plate of the fixed frame. The simulated coal and rock is installed in the simulated coal and rock fixed frame. When it is necessary to simulate coal and rock with different hardness, it can be realized by replacing the simulated coal and rock unit.
[0014] The advantages of the present invention are: (1) It can truly simulate the process of cutting teeth cutting coal and conduct single cutting tooth cutting experiments; (2) It can conduct different cutting tooth cutting experiments, and can adjust the cutting tooth wedge angle, traction speed, and mine pressure, and can also cut coal and rock with different hardness; (3) It can identify the coal and rock boundary by analyzing the change of the cutting tooth force. The above invention is applied underground and can solve the technical problem of coal and rock boundary identification. Therefore, it has certain economic benefits. Description of the Drawings
[0015] Appendix Figure 1 is the front view of the structural schematic diagram of a cutting performance test experimental system of the present invention, Figure 2It is a top view of the structural schematic diagram of a cutting performance test experimental system of the present invention. Figure 3 It is a front view of the movable experimental bench of the present invention. Figure 4 It is a top view of the movable experimental bench of the present invention. Figure 5 It is a left view of the movable experimental bench of the present invention. Figure 6 It is a cross-sectional view of the movable experimental bench of the present invention at the A-A position. Figure 7 It is a structural schematic diagram of the pick holder. Among them, 1 is the left side plate of the fixed frame, 2 is the simulated coal and rock, 3 is the fifth pressure regulating connecting rod, 4 is the fourth pressure regulating connecting rod, 5 is the top plate of the fixed frame, 6 is the third pressure regulating connecting rod, 7 is the pressure regulating movable plate, 8 is the first pressure regulating connecting rod, 9 is the sixth pressure regulating connecting rod, 10 is the nut, 11 is the first bolt, 12 is the side fixing plate, 13 is the pressure regulating screw rod, 14 is the pressure regulating wrench, 15 is the side plate of the coal and rock frame, 16 is the right side plate of the fixed frame, 17 is the second pressure regulating connecting rod, 18 is the bottom plate of the fixed frame, 19 is the frame body, 20 is the slide rail, 21 is the locking nut, 22 is the second bolt, 23 is the pick holder, 24 is the inverted T-shaped groove structure, 25 is the pick, 26 is the pick seat, 27 is the pick mounting sleeve, 28 is the force measuring sensor, 29 is the bottom plate of the coal and rock frame. 30 is the hydraulic pump, 31 is the piston, 32 is the hydraulic cylinder, 33 is the data acquisition system, 40 is the U-shaped groove, 41 is the back plate of the fixed frame. Specific embodiments
[0016] A cutting performance test experimental system, which is composed of the following components: a movable experimental bench, a simulated coal and rock unit, a fixed frame, a mine pressure adjustment device, a piston 31, a hydraulic pump 30, a hydraulic cylinder 32 and a data acquisition device 33. The simulated coal and rock unit 2 is installed inside the fixed frame. The mine pressure adjustment device is connected to the fixed frame by a threaded connection. The piston 31 is hinged to the simulated coal wall fixing frame.
[0017] The simulated coal and rock unit is composed of the simulated coal and rock 2, two side plates 15 of the coal and rock frame, and the bottom plate 29 of the coal and rock frame. The two side plates 15 of the coal and rock frame are respectively vertically connected to the bottom plate 29 of the coal and rock frame by welding. The simulated coal and rock 2 is a cuboid, which is placed in the cuboid open frame composed of two side plates 15 of the coal and rock frame and the bottom plate 29 of the coal and rock frame.
[0018] The movable experimental bench is composed of a frame body 19, a slide rail 20, a cutting device, a locking nut 21, and a bolt 22. There are two inverted T-shaped structures 24 at the bottom of the frame body 19, and the two inverted T-shaped structures 24 are symmetrically distributed. The cross-section of the slide rail 19 has two inverted T-shaped grooves, and the two inverted T-shaped structures are symmetrically distributed. The inverted T-shaped structures at the bottom of the movable experimental bench are installed in the inverted T-shaped of the slide rail 20 and slide along the direction perpendicular to the inverted T-shaped groove. At the bottom of the movable experimental bench, in the direction perpendicular to the inverted T-shaped structure, there is a U-shaped groove 40 for installing and removing the first bolt 11.
[0019] The cutting device includes a pick holder 23 and a number of force measuring units. Each force measuring unit consists of a pick socket 26, a force sensor 28, a pick 25 and a pick mounting sleeve 27. Each force measuring unit forms a different angle with the axis of the pick holder 23. Therefore, when the pick holder 23 rotates by a certain angle, other force measuring units can be used to cut coal and rock, and the angle between the pick on this force measuring unit and the wedged coal and rock changes. Thus, cutting experiments on coal and rock with different pick wedging angles are carried out.
[0020] The cutting device is installed above the body 19 of the movable experimental bench. The lower surface of the movable experimental bench has a stepped through-hole structure, and the center of the pick holder 23 has a through-hole structure. The bolt 22 passes through the stepped through-hole on the lower surface of the movable experimental bench and the through-hole in the center of the pick holder 23 to connect the movable experimental bench and the pick holder 23 together, and is locked by the lock nut 21 at the same time. When it is necessary to test picks with different wedging angles, loosen the lock nut 21 to rotate the pick holder 23 by a certain angle, then the pick with another wedging angle cuts the coal and rock.
[0021] The outer shape of the pick holder 23 is a cylinder. The axes of the four pick sockets 26 are inclined to the axis of the pick holder 23 and are installed on the cylindrical outer surface of the pick holder, evenly distributed around the circumference, but with different inclination angles. The connection method between the pick socket 26 and the pick holder 23 is welding. The pick 25 and the force sensor 28 on the pick holder 23 are installed in the pick socket 26.
[0022] The hydraulic cylinder 32 is hinged to the side of the movable experimental bench. When the piston 31 of the hydraulic cylinder 32 expands and contracts, it pushes the hydraulic cylinder 32 to move, so that the movable experimental bench slides along the inverted T-shaped groove. The hydraulic pump 30 can control the moving speed of the movable experimental bench by controlling the flow rate of the hydraulic cylinder 32, so as to simulate different traction speeds.
[0023] When the movable experimental bench slides along the inverted T-shaped groove, it drives the cutting device to move horizontally. When the pick 25 moves to the simulated coal and rock unit 2, the pick 25 starts to cut the coal and rock. The force sensor 28 in the pick socket 26 is subjected to an external force, and the test data is input into the data acquisition system 33 to complete a cutting performance test. At the same time, this experimental system can simulate coal and rock with different hardness by replacing the movable simulated coal and rock unit.
[0024] The strata pressure adjusting device includes a pressure adjusting movable plate 7, a pressure adjusting wrench 14, a pressure adjusting screw rod 13, a first pressure adjusting connecting rod 8, a second pressure adjusting connecting rod 17, a third pressure adjusting connecting rod 6, a fourth pressure adjusting connecting rod 4, a fifth pressure adjusting connecting rod 3, a sixth pressure adjusting connecting rod 9, a side fixing plate 12, a first bolt 11, and a nut 10. The side fixing plate 12 is installed on the outside of the fixed frame and is in surface contact with the side plate of the fixed frame, and is connected by a number of first bolts 11. The side fixing plate 12 is rectangular in shape and has a threaded hole in the middle. The pressure adjusting screw rod 13 is screwed into the threaded hole of the side fixing plate 12. The pressure adjusting wrench 14 is of a cylindrical structure. The pressure adjusting screw rod 13 is cylindrical in shape and has an external thread in the middle. There is a cylindrical hole on the outer cylindrical surface of one side, and the axis of this hole is perpendicular to and intersects the axis of the pressure adjusting screw rod 13. The pressure adjusting wrench 14 is installed in the cylindrical hole of the pressure adjusting screw rod 13. When the pressure adjusting wrench 13 is rotated, the pressure adjusting screw rod 14 moves horizontally along its own axis. The pressure adjusting screw rod 13 is connected to the sixth pressure adjusting connecting rod 9 by a thread. The other end of the sixth pressure adjusting connecting rod 9 is respectively hinged to the first pressure adjusting connecting rod 8, the third pressure adjusting connecting rod 6, and the second pressure adjusting connecting rod 17. One side of the third pressure adjusting connecting rod 6 is hinged to the first pressure adjusting connecting rod 8 and the second pressure adjusting connecting rod 17, and the other side is hinged to the fourth pressure adjusting connecting rod 4 and the fifth pressure adjusting connecting rod 3. The first pressure adjusting connecting rod 8, the second pressure adjusting connecting rod 17, the third pressure adjusting connecting rod 6, the fourth pressure adjusting connecting rod 4, and the fifth pressure adjusting connecting rod 3 are all cylindrical in shape. The second pressure adjusting connecting rod 17 and the fourth pressure adjusting connecting rod 4 are connected to the pressure adjusting movable plate 7. When the pressure adjusting screw rod 13 rotates, the pressure adjusting movable plate 7 moves downward, changing the pressure on the coal wall, thereby simulating different strata pressures.
[0025] The fixed frame is of a welded structure and includes two left side plates 1 of the fixed frame, a right side plate 16 of the fixed frame, a bottom plate 18 of the fixed frame, a top plate 5 of the fixed frame, and a back plate 41 of the fixed frame. The simulated coal and rock unit 2 is installed in the fixed frame 102.
Claims
1. A cutting performance test experimental system, characterized in that: the experimental system is composed of the following components as follows: a movable experimental bench, a simulated coal and rock unit, a fixed frame, a mine pressure adjustment device, a piston (31), a hydraulic pump (30), a hydraulic cylinder (32) and a data acquisition system (33). The simulated coal and rock unit is installed inside the fixed frame. The mine pressure adjustment device is connected to the fixed frame by a threaded connection. The piston (31) is hinged to the simulated coal wall fixing bracket; The movable experimental bench is composed of a bench body (19), a slide rail (20), a cutting device, a lock nut (21), and a bolt two (22). There are two inverted T-shaped structures (24) at the bottom of the bench body (19), and the two inverted T-shaped structures (24) are symmetrically distributed. The cross-section of the slide rail (20) has two inverted T-shaped grooves, and the two inverted T-shaped structures are symmetrically distributed. The inverted T-shaped structure at the bottom of the movable experimental bench is installed in the inverted T of the slide rail (20) and slides along the direction perpendicular to the inverted T-shaped groove. At the bottom of the movable experimental bench, in the direction perpendicular to the inverted T-shaped structure, there is a U-shaped groove (40) for facilitating the installation and removal of bolt one (11); The cutting device includes a pick holder (23) and a number of force measuring units. The force measuring unit is composed of a pick tooth seat (26), a force measuring sensor (28), a pick (25) and a pick mounting sleeve (27). Each force measuring unit forms a different angle with the axis of the pick holder (23); The cutting device is installed above the bench body (19) of the movable experimental bench. The lower surface of the movable experimental bench has a stepped through-hole structure, and the center of the pick holder (23) has a through-hole structure. The bolt two (22) passes through the stepped through-hole on the lower surface of the movable experimental bench and the through-hole in the center of the pick holder (23) to connect the movable experimental bench and the pick holder (23) together, and is locked by the lock nut (21) at the same time; The pick holder (23) is cylindrical in shape. The axes of the four pick tooth seats (26) are inclined to the axis of the pick holder (23) and are installed on the outer cylindrical surface of the pick holder, evenly distributed around the circumference, but with different inclination angles. The connection method between the pick tooth seat (26) and the pick holder (23) is welding. The pick (25) and the force measuring sensor (28) on the pick holder (23) are installed in the pick tooth seat (26); The hydraulic cylinder (32) is hinged to the side of the movable experimental bench. When the piston (31) of the hydraulic cylinder (32) expands and contracts, it pushes the hydraulic cylinder (32) to move, causing the movable experimental bench to slide along the inverted T-shaped groove. The hydraulic pump (30) can control the moving speed of the movable experimental bench by controlling the flow rate of the hydraulic cylinder (32).
2. A cutting performance test experimental system according to claim 1, characterized in that: the simulated coal and rock unit is composed of simulated coal and rock (2), two coal and rock frame side plates (15), and a coal and rock frame bottom plate (29). The two coal and rock frame side plates (15) are respectively vertically connected to the coal and rock frame bottom plate (29) by welding. The simulated coal and rock (2) is a cuboid and is placed in a cuboid open frame composed of two coal and rock frame side plates (15) and a coal and rock frame bottom plate (29). The simulated coal and rock unit (2) is installed in the fixed frame.
3. The cutting performance test experimental system according to claim 1, wherein the technical feature is that when the movable experimental bench slides along the inverted T-shaped groove, it drives the cutting device to move horizontally. When the cutting teeth (25) move to the simulated coal and rock unit (2), the cutting teeth (25) start to cut the coal and rock. The force sensor (28) in the cutting tooth seat (26) is subjected to an external force, and the test data is input into the data acquisition system (33) to complete a cutting performance test.
4. The cutting performance test experimental system according to claim 1, wherein the technical feature is that the mine pressure adjustment device includes a pressure regulating movable plate (7), a pressure regulating wrench (14), a pressure regulating screw rod (13), a pressure regulating connecting rod one (8), a pressure regulating connecting rod two (17), a pressure regulating connecting rod three (6), a pressure regulating connecting rod four (4), a pressure regulating connecting rod five (3), a pressure regulating connecting rod six (9), a side fixing plate (12), a bolt one (11), and a nut (10); the side fixing plate (12) is installed on the outside of the fixed frame and is in surface contact with the side plate of the fixed frame, and is connected by a plurality of bolts one (11); the side fixing plate (12) is in the shape of a cuboid with a threaded hole in the middle. The pressure regulating screw rod (13) is screwed into the threaded hole of the side fixing plate (12). The pressure regulating wrench (14) is of a cylindrical structure. The pressure regulating screw rod (13) is in the shape of a cylinder with an external thread in the middle. There is a cylindrical hole on the outer cylindrical surface of one side, and the axis of the hole is perpendicular to the axis of the pressure regulating screw rod (13). The pressure regulating wrench (14) is installed in the cylindrical hole of the pressure regulating screw rod (13). When the pressure regulating wrench (14) is rotated, the pressure regulating screw rod (13) moves horizontally along its own axis; the pressure regulating screw rod (13) is connected to the pressure regulating connecting rod six (9) by a thread. The other ends of the pressure regulating connecting rod six (9) are respectively hinged to the pressure regulating connecting rod one (8), the pressure regulating connecting rod three (6), and the pressure regulating connecting rod two (17). One side of the pressure regulating connecting rod three (6) is hinged to the pressure regulating connecting rod one (8) and the pressure regulating connecting rod two (17), and the other side is hinged to the pressure regulating connecting rod four (4) and the pressure regulating connecting rod five (3); the pressure regulating connecting rod one (8), the pressure regulating connecting rod two (17), the pressure regulating connecting rod three (6), the pressure regulating connecting rod four (4), and the pressure regulating connecting rod five (3) are all in the shape of a cylinder; the pressure regulating connecting rod two (17) and the pressure regulating connecting rod four (4) are connected to the pressure regulating movable plate (7); when the pressure regulating screw rod (13) rotates, the pressure regulating movable plate (7) moves downward, changing the pressure on the coal wall, thereby simulating different mine pressures.
5. The cutting performance test experimental system according to claim 1, wherein the technical feature is that the fixed frame is a welded structure, including two left side plates of the fixed frame (1), a right side plate of the fixed frame (16), a bottom plate of the fixed frame (18), a top plate of the fixed frame (5), and a back plate of the fixed frame (41).
Citation Information
Patent Citations
Multi-pick parameter adjustable rotary coal cutting experimental device
CN102967476A
Cutting performance test experiment system
CN213022628U