Comprehensive test system and test method for coal body crushing and dust production characteristics of heading machine

Abstract

The invention discloses a comprehensive test system for coal crushing and dust production characteristics of a heading machine, which comprises a bracket, a cutting device connected above the bracket, a confining pressure loading device connected to the power output end of the cutting device, a uniaxial compression device connected to the outer side of the confining pressure loading device above the bracket, a vibrating screening device corresponding to the confining pressure loading device is arranged below the support, a placing plate is connected to the support and located below the cutting device, and a main control box and a dust collecting and analyzing device connected with the vibrating screening device are arranged on the placing plate; and the main control box is connected with and controls the cutting device, the confining pressure loading device, the single-shaft compression device, the vibration screening device and the dust collecting and analyzing device. The device can comprehensively simulate actual working conditions, not only can cut the coal body and quantitatively analyze the particle size of cut dust, but also can measure the compressive strength of the coal body, and provides a basis for dust prevention and control and tunneling process optimization in coal mining.

Description

Technical Field

[0001] The invention belongs to the technical field of cutting and crushing dust reduction, and particularly relates to a comprehensive test system and test method for the crushing and dust generation characteristics of a roadheader coal body. Background Technique

[0002] With the continuous improvement of the mechanization degree of coal mining, roadheaders have been widely used in coal mine mining. However, a large amount of dust is generated when the pick of the roadheader cuts the coal body, which not only seriously affects the working environment, endangers the physical health of workers, but also may cause safety accidents such as dust explosion. At the same time, the crushing characteristics of the coal body are also directly related to problems such as tunneling efficiency and equipment wear. At present, although there are some related test devices and methods, most of them have problems such as single function, inability to comprehensively and accurately simulate actual working conditions, and inability to simultaneously conduct comprehensive tests on crushing and dust generation characteristics. For example, some devices can only measure the dust concentration, but cannot analyze the particle size distribution and dust generation law of the dust; or can only observe the surface crushing situation of the coal body, and cannot deeply study the internal crushing mechanism. Summary of the Invention

[0003] The purpose of the invention is to provide a comprehensive test system and test method for the crushing and dust generation characteristics of a roadheader coal body, which can comprehensively simulate actual working conditions, not only cut the coal body and quantitatively analyze the particle size of the cutting dust, but also measure the compressive strength of the coal body, providing a basis for dust prevention and tunneling process optimization in coal mine mining.

[0004] To achieve the above purpose, the invention provides a comprehensive test system for the crushing and dust generation characteristics of a roadheader coal body, including a bracket, a cutting device is connected above the bracket, a confining pressure loading device is connected to the power output end of the cutting device, a uniaxial compression device is connected outside the confining pressure loading device above the bracket, a vibration screening device is arranged corresponding to the confining pressure loading device below the bracket, a placement plate is connected below the cutting device on the bracket, a main control box and a dust collection and analysis device connected to the vibration screening device are arranged on the placement plate, and the main control box is connected to control the cutting device, the confining pressure loading device, the uniaxial compression device, the vibration screening device, and the dust collection and analysis device.

[0005] As a further scheme of the invention: the cutting device includes a cutting machine base, a cutting oil cylinder, and a support plate. The support plate is connected to the bracket through a left and right slide rail and slider device and is driven by a hand-rolled ball screw sleeve connection. The fixed end of the cutting oil cylinder is connected above the support plate, the movable end of the cutting oil cylinder is connected to the cutting machine base, a linear displacement sensor for monitoring the displacement change of the cutting machine base is installed on the side of the cutting oil cylinder, the cutting machine base is connected to the support plate through a front and rear slide rail and slider device, the power output end of the cutting machine base is connected with a tunneling pick, and a three-dimensional force sensor for real-time monitoring of the cutting force is installed in the middle of the cutting machine base.

[0006] As a further solution of the present invention: The confining pressure loading device includes a confining pressure frame, a transparent protective cover is connected to the outside of the confining pressure frame, a confining pressure device and a specimen space are arranged inside, a dust sensor is connected to the inner wall of the confining pressure frame above the confining pressure device, a funnel is connected to the lower part of the confining pressure frame, and a pull-out plate is inserted at the connection of the funnel and the confining pressure frame corresponding to the specimen space.

[0007] As a further solution of the present invention: The vibration screening device includes a motor, a vibration frame and a spring base, a support base is connected to the lower part of the motor, a vibration connecting rod is connected to the power output end of the motor, the other end of the vibration connecting rod is connected to the outer side wall of the vibration frame, the vibration frame is arranged below the confining pressure loading device, a screen device is connected inside the vibration frame, and the vibration frame is connected to the spring base through a spring device below.

[0008] As a further solution of the present invention: The screen device includes screen I, screen II, screen III and screen IV with gradually decreasing pore diameters, and they are all installed inside the vibration frame from top to bottom in a direction inclined 10° horizontally downward.

[0009] As a further solution of the present invention: The dust collection and analysis device includes a transparent partition, a conveyor belt device matching the screen device is connected inside the transparent partition, the conveyor belt device includes conveyor belt I, conveyor belt II, conveyor belt III, conveyor belt IV and conveyor belt V, and they are all placed from top to bottom in a direction inclined 10° horizontally downward, one end is respectively placed corresponding to the lower part of the screen device, the other end is respectively connected with a cleaning device, a dust collection plate is connected below the cleaning device, and a dust collection chamber is formed. A drawer is arranged at the bottom of the dust collection chamber, and a gravity sensor is installed below the drawer.

[0010] As a further solution of the present invention: The uniaxial compression device includes a uniaxial compression base, a lower bottom plate is connected above the uniaxial compression base through a lower compression shaft, columns are symmetrically connected to both sides of the uniaxial compression base, the tops of the columns are commonly connected with an upper top plate, a uniaxial compression force sensor is connected below the upper top plate corresponding to the lower bottom plate, and a bearing plate is installed below the uniaxial compression force sensor.

[0011] As a further solution of the present invention: Replacement picks are placed on the placement plate, including pick I, pick II and pick III, and annular grooves are provided on pick I, pick II and pick III; the cone angle of pick I is 80°, and a wear-resistant layer and spiral protrusions are provided at the top; the cone angle of pick II is 60°, and a circular protrusion is provided at the top; the cone angle of pick III is 40°.

[0012] To achieve the above object, the present invention also provides a test method for a comprehensive test system for the coal body crushing and dust generation characteristics of a roadheader, including the following steps:

[0013] Step 1: Select a coal sample for testing, process the coal sample into a standard specimen, and divide it into two parts;

[0014] Step 2: Measure the compressive strength of a part of the specimens using a uniaxial compression device; place another part of the specimens into a confining pressure loading device and perform cutting using a cutting device.

[0015] Step 3: After the cutting is completed, the dust generated by the cutting enters a vibrating screening device, and dust of different particle sizes is obtained through vibrating screening.

[0016] Step 4: Classify and collect the dust of different particle sizes through a dust collection and analysis device, and perform quantitative analysis.

[0017] Determine the size of the rotation speed R of the tunneling pick and the contact area A of the tunneling pick, and calculate the cutting dust particle size coefficient λ according to the following formula target :

[0018]

[0019] In the formula: k1 is a proportionality constant, indicating the influence of the contact area A of the tunneling pick on the particle size; k2 is another proportionality constant, indicating the influence of the rotation speed R of the tunneling pick on the particle size; P is the compressive strength of the coal.

[0020] Step 5: Conduct multiple groups of cutting experiments according to the size of the contact area A of the tunneling pick and the rotation speed R of the tunneling pick, and compare the average value of the actually obtained dust particle size with the cutting dust particle size coefficient λ target to verify the feasibility of the calculation method.

[0021] Furthermore, the specific test steps of the uniaxial compression device are as follows:

[0022] S1. Start the uniaxial compression device and load at a certain speed until the specimen fails.

[0023] S2. Record the failure load and the phenomena occurring during the pressurization process, describe the specimen after failure, and observe the failure mode; calculate the compressive strength of the coal according to the recorded failure load and the initial bearing area of the specimen. The calculation formula is:

[0024]

[0025] In the formula: P is the compressive strength of the coal, with the unit of megapascal (MPa); P f is the specimen failure load, with the unit of kilonewton (kN); F is the initial bearing area of the specimen, with the unit of square centimeter (cm 2 ).

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] 1. It can comprehensively simulate the actual working conditions. It can not only cut coal and quantitatively analyze the particle size of the cutting dust, but also measure the compressive strength of the coal through uniaxial compression, and study the dust generation characteristics of the roadheader pick by comprehensively considering the contact area of the roadheader pick and the rotation speed of the roadheader pick, so as to reduce the cutting dust generation intensity and improve the cutting efficiency, providing a basis for dust prevention and control and roadheader technology optimization in coal mining.

[0028] 2. The cutting device can be conveniently adjusted in position through the left and right slide rail and slider device, and the cutting situation can be monitored in real time by using linear displacement sensors and three-dimensional force sensors.

[0029] 3. The confining pressure loading device cooperating with the cutting device not only ensures the safety of cutting, but also avoids dust pollution of the test environment generated by cutting.

[0030] 4. The vibrating screen device cooperating with the dust collection and analysis device can collect and analyze dust of different particle sizes;

[0031] 5. Equipped with replaceable picks, it can deal with coal and rock of different hardnesses. All replaceable picks have annular grooves, which can be used to evacuate debris. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Shows a three-dimensional schematic diagram of the present invention;

[0033] Figure 2 Shows a schematic diagram of the cutting device;

[0034] Figure 3 Shows a three-dimensional schematic diagram of the confining pressure loading device;

[0035] Figure 4 Shows an internal schematic diagram of the confining pressure loading device;

[0036] Figure 5 Shows a schematic diagram of the internal connection of the vibrating screen device and the dust collection and analysis device;

[0037] Figure 6 Shows a schematic diagram of the vibrating screen device;

[0038] Figure 7 Shows a schematic diagram of the dust collection and analysis device;

[0039] Figure 8 Shows Figure 7 A partial enlarged view of part A in;

[0040] Figure 9 Shows a schematic diagram of the replaceable pick;

[0041] Figure 10 Shows a schematic diagram of the uniaxial compression device.

[0042] In the figure: 1. Cutting device, 11. Roadheader pick, 12. Three-dimensional force sensor, 13. Roadheader base, 14. Cutting oil cylinder, 15. Linear displacement sensor, 16. Front and rear slide rail and slider device, 17. Left and right slide rail and slider device, 18. Hand-rocking ball screw set, 19. Support plate;

[0043] 2. Confining pressure loading device, 21. Specimen space, 22. Confining pressure vessel, 23. Confining pressure frame, 24. Drawer plate, 25. Dust sensor, 26. Hopper, 27. Transparent protective cover;

[0044] 3. Vibration screening device, 31. Vibration frame, 32. Screen device, 321. Screen I, 322. Screen II, 323. Screen III, 324. Screen IV, 33. Spring device, 34. Spring base, 35. Vibration connecting rod, 36. Motor, 37. Support base;

[0045] 4. Dust collection and analysis device, 41. Conveyor belt device, 411. Conveyor belt I, 412. Conveyor belt II, 413. Conveyor belt III, 414. Conveyor belt IV, 415. Conveyor belt V, 42. Cleaning device, 43. Dust collection plate, 44. Drawer, 45. Gravity sensor, 46. Transparent partition;

[0046] 5. Main control box;

[0047] 6. Replacement pick, 611. Wear-resistant layer, 612. Spiral protrusion, 621. Circular protrusion, 64. Annular groove;

[0048] 7. Uniaxial compression device, 71. Upper roof plate, 72. Upper roof support pillar, 73. Uniaxial compression force sensor, 74. Bearing plate, 75. Lower bottom plate, 76. Lower compression shaft, 77. Uniaxial compression base;

[0049] 8. Bracket, 9. Fixed frame, 10. Placing plate. Specific embodiments

[0050] The present invention will be further described below through embodiments.

[0051] Such as Figure 1As shown in the figure, a comprehensive test system for the coal body crushing and dust generation characteristics of a roadheader includes a support 8. Above the support 8, a cutting device 1 is connected. The power output end of the cutting device 1 is connected to a confining pressure loading device 2. Above the support 8 and outside the confining pressure loading device 2, a uniaxial compression device 7 is connected. Below the support 8 and corresponding to the confining pressure loading device 2, a vibrating screening device 3 is provided. On the support 8 and below the cutting device 1, a placement plate 10 is connected. On the placement plate 10, a main control box 5 and a dust collection and analysis device 4 connected to the vibrating screening device 3 are provided. The main control box 5 is connected to control the cutting device 1, the confining pressure loading device 2, the uniaxial compression device 7, the vibrating screening device 3, and the dust collection and analysis device 4.

[0052] Each component cooperates with each other and has diverse functions, capable of comprehensively simulating the actual working conditions and comprehensively analyzing the crushing and dust generation characteristics at the same time.

[0053] Preferably, a fixing frame 9 is provided on the support 8. The fixing frame 9 is installed around the uniaxial compression device 7 and is connected to the outer side wall of the confining pressure loading device 2, playing a role of fixing and supporting.

[0054] Furthermore, as Figure 2 shown, the cutting device 1 includes a cutting machine base 13, a cutting oil cylinder 14, and a support plate 19. Below the support plate 19, it is connected to the support 8 through a left and right slide rail and slider device 17 and is driven by a hand-cranked ball screw sleeve 18. The fixed end of the cutting oil cylinder 14 is connected above the support plate 19, and the movable end of the cutting oil cylinder 14 is connected to the cutting machine base 13. A linear displacement sensor 15 for monitoring the displacement change of the cutting machine base 13 is installed on the side of the cutting oil cylinder 14. Below the cutting machine base 13, it is connected to the support plate 19 through a front and rear slide rail and slider device 16. The power output end of the cutting machine base 13 is connected to a roadheader pick 11, and a three-dimensional force sensor 12 for real-time monitoring of the cutting force is installed in the middle of the cutting machine base 13.

[0055] By cooperating the hand-cranked ball screw sleeve 18 with the cutting oil cylinder 14, the position of the cutting machine base 13 can be adjusted. Then, during the cutting process, the three-dimensional force sensor 12 monitors the cutting force in real time, and the linear displacement sensor 15 monitors the displacement change of the cutting machine base 13.

[0056] Furthermore, as Figure 3 and Figure 4As shown in the figure, the confining pressure loading device 2 includes a confining pressure frame 23 which functions as a fixed support. A transparent protective cover 27 is connected to the outside of the confining pressure frame 23. Inside, there is a confining pressure device 22 and a specimen space 21. The specimen is placed in the specimen space 21 and fixed by the confining pressure device 22. A dust sensor 25 is connected to the inner wall of the confining pressure frame 23 above the confining pressure device 22. The dust concentration can be monitored in real time through the dust sensor 25. A funnel 26 is connected to the bottom of the confining pressure frame 23. A pull-out plate 24 is inserted at the connection of the funnel 26 and the confining pressure frame 23 corresponding to the specimen space 21. The pull-out plate 24 plays a separation role. As the pull-out plate 24 is pulled out, the cut dust can fall into the vibrating screening device through the funnel 26, effectively reducing the dust dispersion.

[0057] Further, as Figure 5 and Figure 6 shown in the figure, the vibrating screening device 3 includes a motor 36, a vibrating frame 31 and a spring base 34. A support base 37 is connected to the bottom of the motor 36. The power output end of the motor 36 is connected to a vibrating connecting rod 35. The other end of the vibrating connecting rod 35 is connected to the outer wall of the vibrating frame 31. The vibrating frame 31 is arranged below the confining pressure loading device 2. A screen device 32 is connected inside the vibrating frame 31. The vibrating frame 31 is connected to the spring base 34 through a spring device 33. The spring device 33 is composed of four springs, which are distributed at the four corners of the spring base 34.

[0058] Further, the screen device 32 includes screen I 321, screen II 322, screen III 323 and screen IV 324 with gradually decreasing pore sizes, and they are all installed inside the vibrating frame 31 from top to bottom in a direction inclined 10° downward horizontally. The multi-level arranged screens can screen the dust generated by cutting, facilitating the collection and analysis by the subsequent dust collection and analysis device 4.

[0059] Further, as Figure 5 、 Figure 7 and Figure 8 shown in the figure, the dust collection and analysis device 4 includes a transparent partition 46. Inside the transparent partition 46, a conveyor belt device 41 matching the screen device 32 is connected. The conveyor belt device 41 includes conveyor belt I 411, conveyor belt II 412, conveyor belt III 413, conveyor belt IV 414 and conveyor belt V 415, which are all placed from top to bottom in a direction inclined 10° downward horizontally. One ends are respectively placed corresponding to the bottom of the screen device 32, and the other ends are respectively connected to a cleaning device 42. A dust collection plate 43 is connected below the cleaning device 42, and a dust collection chamber is formed. A drawer 44 is arranged at the bottom of the dust collection chamber, and a gravity sensor 45 is installed below the drawer 44. Different pore-sized dust classified and screened by the screen device 32 is sent into different drawers 44 for classified collection through the conveyor belt device 41.

[0060] The cleaning device 42 is made of a polyurethane alloy rubber composite material. Polyurethane has excellent wear resistance, the alloy has high hardness and strength and can withstand large pressures and frictional forces, and the rubber has excellent elasticity and can automatically adjust the contact pressure between the wiper blade of the cleaner and the conveyor belt using its elastic properties, so that the force on the wiper blade and the running conveyor belt is within an appropriate range; this material combines the advantages of polyurethane, alloy, and rubber and has characteristics such as high wear resistance, high strength, and good elasticity, which not only ensures the cleaning effect, effectively removes the materials on the conveyor belt, and reduces the problem of incomplete cleaning caused by wiper blade wear, but also does not cause excessive extrusion and damage to the conveyor belt, and can also absorb vibrations and impacts during the cleaning process to a certain extent and reduce noise.

[0061] Further, as Figure 10 shown, the uniaxial compression device 7 includes a uniaxial compression base 77. Above the uniaxial compression base 77, a lower base plate 75 is connected through a lower compression shaft 76. On both sides of the uniaxial compression base 77, symmetrically connected are support columns 72. The tops of the support columns 72 are jointly connected to an upper top plate 71. Below the upper top plate 71 and corresponding to the lower base plate 75, a uniaxial compression force sensor 73 is connected. Below the uniaxial compression force sensor 73, a bearing plate 74 is installed.

[0062] Further, as Figure 9 shown, a replacement pick 6 is placed on the placement plate 10, including pick I, pick II, and pick III. Ring-shaped grooves 64 are provided on pick I, pick II, and pick III, which can evacuate debris; the cone angle of pick I is 80°, and a wear-resistant layer 611 and a spiral protrusion 612 are provided at the top. The wear-resistant layer 611 is used to enhance wear resistance, and the spiral protrusion 612 is provided to enhance the cutting effect, and it is suitable for cutting coal and rock with a hardness coefficient f in the range of 5 - 6; the cone angle of pick II is 60°, and a circular protrusion 621 is provided at the top. The circular protrusion 621 can not only enhance wear resistance but also ensure the sharpness of the top, and it is suitable for cutting coal and rock with a hardness coefficient f in the range of 3 - 4; the cone angle of pick III is 40°, and its shape is approximately conical, and the top is relatively sharp to better cut into coal and rock, and it is suitable for cutting coal and rock with a hardness coefficient f in the range of 2 - 3.

[0063] A test method for a comprehensive test system for coal body crushing and dust generation characteristics of a roadheader, characterized by including the following steps:

[0064] Step 1: Select a coal sample for testing, process the coal sample into a standard test piece, and divide it into two parts;

[0065] Step 2: Use the uniaxial compression device 7 to measure the compressive strength of one part of the test piece; put the other part of the test piece into the confining pressure loading device 2 and use the cutting device 1 to cut it;

[0066] Step 3: After the cutting is completed, the dust generated by the cutting enters the vibrating screening device 3, and dust of different particle sizes is obtained through vibrating screening;

[0067] Step 4: The dust of different particle sizes is classified and collected by the dust collection and analysis device 4, and quantitative analysis is carried out;

[0068] Determine the size of the rotation speed R of the tunneling pick and the contact area A of the tunneling pick, and calculate the cutting dust particle size coefficient λ according to the following formula target of the size:

[0069]

[0070] In the formula: k1 is a proportional constant, representing the influence of the contact area A of the tunneling pick 11 on the particle size. Specifically, the larger k1 is, the greater the influence of the contact area of the tunneling pick 11 on the particle size; k2 is another proportional constant, representing the influence of the rotation speed R of the tunneling pick 11 on the particle size. Specifically, the larger k2 is, the greater the influence of the rotation speed of the tunneling pick 11 on the particle size; P is the compressive strength of the coal, and and are used in the formula to represent the influence of the compressive strength of the coal on the particle size. The greater the compressive strength of the coal, the smaller the influence factor (denominator), indicating the greater the influence on the particle size;

[0071] represents the influence of the contact area A of the tunneling pick 11 on the particle size. The larger A is, the larger the particle size; the larger P is, the smaller the particle size;

[0072] represents the influence of the rotation speed R of the tunneling pick 11 on the particle size. The larger R is, the larger the particle size; the larger P is, the smaller the particle size;

[0073] Step 5: Conduct multiple groups of cutting experiments according to the size of the contact area A of the tunneling pick 11 and the rotation speed R of the tunneling pick 11, and compare the average value of the actually obtained dust particle size with the cutting dust particle size coefficient λ target for comparison to verify the feasibility of the calculation method.

[0074] Furthermore, the specific test steps of the uniaxial compression device 7 are as follows:

[0075] S1. Start the uniaxial compression device 7 and load at a certain speed until the specimen fails;

[0076] S2. Record the failure load and the phenomena that occur during the pressurization process, describe the specimen after failure, and observe the failure mode; calculate the compressive strength of the coal according to the recorded failure load and the initial bearing area of the specimen. The calculation formula is:

[0077]

[0078] Where: P is the compressive strength of coal, in megapascals (MPa); f is the specimen failure load, in kN; F is the initial pressure bearing area of ​​the specimen, in cm2 2 ).

[0079] When implementing:

[0080] Step 1: Select the coal sample for testing, process the coal sample into a standard specimen, and divide it into two parts;

[0081] Step 2: Place a portion of the test piece on the upper side of the lower bottom plate 75, with the top in contact with the pressure plate 74, and adjust the position so that the force on the upper and lower sides of the test piece is uniform;

[0082] Step 3: Start the uniaxial compression device 7 and load at a speed of 0.005 mm / s until the specimen is destroyed;

[0083] Step 4: Record the failure load as 55.9 kN and the initial bearing area of ​​the specimen as 19.6 cm 2 , the uniaxial compressive strength of coal is obtained as:

[0084]

[0085] Step 5: Set the speed R of the driving pick 11 to 45 rpm and the contact area A of the driving pick 11 to 35 cm 2 , take k1 = 1.96, k2 = 2.86, and calculate the cut dust particle size coefficient λ target for:

[0086]

[0087] Step 6: Turn on the power, open the main control box 5, start the confining pressure device 22 to fix the other part of the test piece, and adjust the position of the cutting machine seat 13 by manually rocking the ball screw set 18 so that the excavation cutter 11 contacts the test piece for cutting;

[0088] Step 7: Set the speed R of the driving pick 11 to 45 rpm and the contact area A of the driving pick 11 to 35 cm 2 , start the excavation pick 11 to cut the test piece;

[0089] Step 8: After the cutting is completed, the vibration screening device 3 is started, the pull-out plate 24 is pulled out, and the cut dust enters the vibration screening device 3 through the funnel 26, and enters the corresponding conveyor belts after vibration screening;

[0090] Step 9: Start the conveyor belt device 41. When the dust reaches the end of the conveyor belt, the cleaning device 42 sweeps the dust onto the dust collection plate 43 and finally into the drawer 44. The particle size ratio of the obtained dust is as follows: the proportion of particles larger than 80μm is 10%, the proportion of particles between 50μm and 80μm is 50%, and the proportion of particles smaller than 50μm is 40%. The average particle size of the dust is 58.46μm, compared with the cutting dust particle size coefficient λ target It can be seen from the comparison that the calculation method is feasible;

[0091] In this implementation case, the compressive strength is calculated to be 28.5MPa, the contact area A of the roadheader pick 11 is 35 cm 2 , and the rotation speed R of the roadheader pick 11 is 45 revolutions per minute for the size of λ target The sizes of other groups of parallel experiments can be calculated according to the foregoing steps after changing the measurement influencing factors.

Claims

1. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader, comprising a support (8), characterized in that: A cutting device (1) is connected above the bracket (8), a power output end of the cutting device (1) is connected to a confining pressure loading device (2), a uniaxial compression device (7) is connected above the bracket (8) and located outside the confining pressure loading device (2), a vibration screening device (3) is provided below the bracket (8) and corresponding to the confining pressure loading device (2), a placement plate (10) is connected below the cutting device (1) on the bracket (8), a main control box (5) and a dust collection and analysis device (4) connected to the vibration screening device (3) are provided on the placement plate (10), and the main control box (5) is connected to control the cutting device (1), the confining pressure loading device (2), the uniaxial compression device (7), the vibration screening device (3), and the dust collection and analysis device (4).

2. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 1, characterized in that: The cutting device (1) comprises a cutting machine seat (13), a cutting cylinder (14) and a support plate (19). The support plate (19) is connected to the bracket (8) through left and right slide rail slider devices (17) at the bottom and is connected and driven by a hand-operated ball screw set (18). The fixed end of the cutting cylinder (14) is connected to the top of the support plate (19). The movable end of the cutting cylinder (14) is connected to the cutting machine seat (13). A linear displacement sensor (15) for monitoring the displacement change of the cutting machine seat (13) is installed on the side of the cutting cylinder (14). The cutting machine seat (13) is connected to the support plate (19) through front and rear slide rail slider devices (16) at the bottom. The power output end of the cutting machine seat (13) is connected to a tunneling pick (11). A three-dimensional force sensor (12) for real-time monitoring of the cutting force is installed in the middle of the cutting machine seat (13).

3. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 1, characterized in that: The confining pressure loading device (2) comprises a confining pressure frame (23), the outer side of the confining pressure frame (23) is connected to a transparent protective cover (27), the inner side of the confining pressure frame (23) is provided with a confining pressure device (22) and a specimen space (21), the inner wall of the confining pressure frame (23) is connected to a dust sensor (25) located above the confining pressure device (22), the lower side of the confining pressure frame (23) is connected to a funnel (26), and a pull-out plate (24) is plugged into the connection between the funnel (26) and the confining pressure frame (23) corresponding to the specimen space (21).

4. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 1, characterized in that: The vibrating screening device (3) comprises a motor (36), a vibrating frame (31) and a spring base (34); a supporting base (37) is connected below the motor (36); a vibrating connecting rod (35) is connected to the power output end of the motor (36); the other end of the vibrating connecting rod (35) is connected to the outer wall of the vibrating frame (31); the vibrating frame (31) is arranged below the confining pressure loading device (2); a screen device (32) is connected inside the vibrating frame (31); and the vibrating frame (31) is connected to the spring base (34) below via a spring device (33).

5. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 4, characterized in that: The screen device (32) comprises a screen I (321), a screen II (322), a screen III (323) and a screen IV (324) with successively decreasing apertures, and all of them are installed from top to bottom inside the vibration frame (31) in a horizontal downwardly inclined direction of 10 degrees.

6. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 5, characterized in that: The dust collecting and analyzing device (4) comprises a transparent partition (46), the interior of which is connected to a conveyor belt device (41) matching the screen device (32), the conveyor belt device (41) comprising a conveyor belt I (411), a conveyor belt II (412), a conveyor belt III (413), a conveyor belt IV (414) and a conveyor belt V (415), all of which are placed from top to bottom in a direction inclined 10° downward from the horizontal, one end of which is respectively placed below the screen device (32), and the other end of which is respectively connected to a cleaning device (42), and a dust collecting plate (43) is connected below the cleaning device (42), so as to form a dust collecting chamber, a drawer (44) is provided at the bottom of the dust collecting chamber, and a gravity sensor (45) is installed below the drawer (44).

7. A comprehensive testing system for coal crushing and dust generation characteristics of a roadheader according to claim 1, characterized in that: The uniaxial compression device (7) comprises a uniaxial compression base (77), a lower base plate (75) is connected to the top of the uniaxial compression base (77) via a lower compression shaft (76), pillars (72) are symmetrically connected to both sides of the uniaxial compression base (77), the tops of the pillars (72) are commonly connected to an upper top plate (71), a uniaxial compression force sensor (73) is connected to the lower base plate (75) below the upper top plate (71), and a pressure plate (74) is installed below the uniaxial compression force sensor (73).

8. A comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to any one of claims 1 to 7, characterized in that: The placement plate (10) is provided with replacement picks (6), including picks I, picks II and picks III, each of which is provided with an annular groove (64); the cone angle of pick I is 80°, and a wear-resistant layer (611) and a spiral protrusion (612) are provided at the top; the cone angle of pick II is 60°, and a circular protrusion (621) is provided at the top; the cone angle of pick III is 40°.

9. The testing method of a comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 2 is characterized in that: The following steps are involved: Step 1: Select the coal sample for testing, process the coal sample into a standard test piece, and divide it into two parts; Step 2: Using a uniaxial compression device (7) to measure the compressive strength of a portion of the test pieces; placing another portion of the test pieces in a confining pressure loading device (2) and cutting them using a cutting device (1); Step 3: After the cutting is completed, the dust generated by the cutting enters the vibration screening device (3), and is vibrated and screened to obtain dust of different particle sizes; Step 4: Classify and collect dust of different particle sizes through the dust collection and analysis device (4), and conduct quantitative analysis; Determine the rotation speed R of the tunneling pick (11) and the contact area A of the tunneling pick (11), and calculate the cutting dust particle size coefficient λ according to the following formula: target Size: Wherein: k1 is a proportional constant, which indicates the influence of the contact area A of the driving pick (11) on the particle size; k2 is another proportional constant, which indicates the influence of the rotation speed R of the driving pick (11) on the particle size; P is the compressive strength of coal; Step 5: Perform multiple cutting experiments according to the contact area A of the tunneling pick (11) and the rotation speed R of the tunneling pick (11), and compare the average dust particle size obtained and the cutting dust particle size coefficient λ target Make a comparison to verify the feasibility of the calculation method.

10. The testing method of the comprehensive testing system for coal body crushing and dust generation characteristics of a roadheader according to claim 9 is characterized in that: The specific test steps of the uniaxial compression device (7) are as follows: S1, start the uniaxial compression device (7), and load the specimen at a certain speed until the specimen is destroyed; S2. Record the failure load and the phenomena that occur during the pressurization process, describe the specimen after failure, and observe the failure form; calculate the compressive strength of the coal based on the recorded failure load and the initial pressure-bearing area of ​​the specimen. The calculation formula is: Where: P is the compressive strength of coal, in megapascals (MPa); f is the specimen failure load, in kN; F is the initial pressure bearing area of ​​the specimen, in cm2 2 ).

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