Method and device for cutting coal through rope saw under pseudo-inclined flexible shield support

Abstract

The invention discloses a method and a device for cutting coal through a rope saw under a pseudo-inclined flexible shield support, and belongs to the technical field of coal mining. The rope saw coal cutting method under the pseudo-inclined flexible shield support comprises the steps that a plurality of to-be-cut drill holes are formed in a pseudo-inclined coal face, a coal face with the dip angle ranging from 25 degrees to 30 degrees is arranged between an air return way and a transportation way in a pseudo-inclined coal face coal seam, the pseudo-inclined coal face is supported by the flexible shield support to form a coal mining section, and the flexible shield support is used for supporting the coal mining section. The average actual dip angle of a coal mining section is larger than 45 degrees, a traction device is used for moving a wire saw into a pseudo-inclined coal mining working face, diamond bead wire saw equipment is used for cutting a coal seam between drill holes to be cut based on a reverse cutting method, and broken coal formed after the coal seam is cut is transferred into a mining area conveying device. According to the method, the pseudo-inclined coal face with the dip angle of 25-30 degrees is constructed between the air return roadway and the transportation roadway, operation in a steeply inclined area is avoided, the construction difficulty is greatly reduced, and the construction convenience and safety are improved.

Description

Technical Field

[0001] This invention belongs to the field of coal mining technology, and in particular relates to a method and device for wire saw cutting coal under a pseudo-inclined flexible shield support. Background Technology

[0002] Steeply inclined coal seams refer to coal seams with a dip angle greater than 45°. These seams are characterized by complex geological conditions, high mining difficulty, challenging support systems, and complex mine pressure manifestations. Currently, the main mining methods for steeply inclined coal seams include horizontal segmented top-coal caving mining, bench mining, storage mining, and high-bottom roadway small-stage top-coal caving mining. These methods generally suffer from problems such as sensitivity to changes in coal seam thickness, high cost, low output, and high coal consumption.

[0003] Therefore, there is an urgent need for new methods for mining steeply inclined coal seams that can efficiently solve the technical problems of low efficiency and high cost in mining steeply inclined coal seams. The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] To address the technical problems of low efficiency and high cost in existing technologies for mining steeply inclined coal seams, a method and apparatus for wire sawing coal under a pseudo-inclined flexible shield support is provided.

[0005] In a first aspect, the present invention provides a method for wire sawing coal under a pseudo-inclined flexible shield support, comprising the following steps: Multiple boreholes to be cut are arranged in a pseudo-inclined coal mining face. The pseudo-inclined coal mining face is a coal mining face with an inclination angle of less than 45° arranged between the return airway and the transport roadway. The pseudo-inclined coal mining face is supported by a flexible shield support to form a coal mining section. The average actual inclination angle of the coal seam in the coal mining section is greater than 45°. The wire saw is moved to the pseudo-inclined coal mining face using a traction device, and the coal seam between the boreholes to be cut is cut using a diamond wire saw based on the reverse cutting method. The crushed coal formed after the coal seam is cut is transferred to the mining area transportation device.

[0006] In some embodiments, the pseudo-inclined coal mining face is a coal mining face with an inclination angle of 25-30° arranged on the coal seam between the return airway and the transport roadway, and the coal mining face is supported by a flexible shield support.

[0007] In some embodiments, arranging multiple boreholes to be cut in the pseudo-inclined coal mining face includes: A drilling rig is used to construct a set of boreholes to be cut at regular intervals on the coal face. Each regular interval is the length of a single cut made by the wire saw.l The number of boreholes to be cut in a group is n, the distance between each group of boreholes is the distance that the wire saw can break the coal seam after cutting, and the diameter of each borehole is d. The cutting length is adapted to the effective cutting length of the wire saw.

[0008] In some embodiments, arranging multiple boreholes to be cut in the pseudo-inclined coal mining face includes: The drilling rig begins construction at the intersection of the coal chute and the pseudo-inclined mining face. A set of boreholes is drilled at regular intervals from bottom to top, where each interval represents the length of a single cut by the wire saw. l The l The number of boreholes to be cut is determined based on the actual occurrence of the coal seam on site, and so on, until the boreholes to be cut are arranged at the intersection of the return airway and the pseudo-inclined coal face. n The distance between each group of boreholes to be cut is the distance at which the wire saw can break the coal seam after cutting, and the diameter of each borehole is d. The distance between each group of boreholes can be the same or different; the distance between each group of boreholes should be set so that the wire saw can break the coal seam when cutting it. In a preferred embodiment, n Based on the distance between the top plate and the bottom plate b It is determined that the distance between boreholes to be cut in the same group is... b 1, n and b The relationship between them is n=b / b 1. After the drilling of the hole to be cut is completed, an easy-to-cut body with a smaller size than the hole to be cut is inserted to prevent the hole from collapsing.

[0009] In some embodiments, arranging multiple boreholes to be cut in the pseudo-inclined coal mining face further includes: The drilling rig begins construction at the intersection of the return airway and the pseudo-inclined coal face cut. A set of boreholes is drilled at regular intervals from top to bottom, where each interval represents the length of a single cut by the wire saw. l The l The number of boreholes in a group is determined based on the actual coal seam conditions at the site, up to the intersection of the cutting face and the coal chute in the pseudo-inclined mining face. The distance between each group of boreholes is the distance at which the wire saw can break the coal seam after cutting. The diameter of each borehole is d. The distance between each group of boreholes can be the same or different; the distance should be set to ensure that the wire saw breaks the coal seam during cutting. In a preferred embodiment, n Based on the distance between the top plate and the bottom plate b It is determined that the distance between boreholes to be cut in the same group is... b 1, n and b The relationship between them is n=b / b 1. After the drilling of the hole to be cut is completed, an easy-to-cut body with a smaller size than the hole to be cut is inserted to prevent the hole from collapsing.

[0010] In some embodiments, the easy-to-cut body comprises a plastic PVC pipe.

[0011] In some embodiments, the selection of the flexible shield support is determined based on the thickness of the coal seam.

[0012] In some embodiments, cutting the coal seam between the boreholes to be cut using a diamond wire saw based on a reverse cutting method includes: The diamond wire saw is wound around the directional guide wheel, and the directional guide wheel is extended into the hole to be cut by the position adjustment device. After reaching the pre-cut position, the position adjustment device is fixed. Adjust the positions of the caster wheel, the directional guide wheel, and the drive wheel, and then pass the diamond bead wire saw around the grooves of the caster wheel, the directional guide wheel, and the drive wheel respectively. Adjust the position and tension of the wire saw machine so that the diamond bead wire saw is in a tensioned state and can cut normally. Start the wire saw machine. Through the high-speed rotation of the drive wheel and the automatic rope winding function of the wire saw machine, the diamond bead wire saw is in a high-speed stepless rotation and continuous tension state driven by the drive wheel of the wire saw machine. This cuts the coal seam between the boreholes to be cut, so as to achieve the purpose of the diamond bead wire saw cutting downward to the pre-cut position. Start the wire saw machine, and use the wire release function of the wire saw machine to make the diamond bead wire saw in a slack state. Take out the position adjustment device, move the position adjustment device to the next set of holes to be cut, and repeat the above cutting operation of the holes to be cut until the coal seam between all the holes to be cut is cut and broken.

[0013] In some embodiments, the position adjustment device includes a hydraulic telescopic rod.

[0014] In some embodiments, transferring the crushed coal formed after the coal seam is cut into the mining area transport device includes: First, the crushed coal formed after the coal seam is cut is scooped onto both sides of the roof and floor. Then, an enamel chute is laid on top. Next, the crushed coal is scooped onto the enamel chute and, by its own weight, flows through the enamel chute into the coal chute. The coal chute directly transfers the crushed coal into the scraper conveyor in the transport roadway and then onto the belt conveyor in the transport roadway. Finally, the crushed coal enters the mining area transport device.

[0015] In some embodiments, after the broken coal formed by cutting the coal seam is transferred to the mining area transportation device, the method further includes: after the coal seam between the boreholes to be cut is mined, the flexible shield support is lowered, and the next section of coal seam is mined using the reverse cutting method.

[0016] In some embodiments, the diamond beaded wire saw device includes a diamond beaded wire saw, which includes a wire rope, an isolation sleeve fitted onto the wire rope, beads fixed onto the wire rope, and diamond abrasive grains embedded in the beads.

[0017] In a second aspect, the present invention provides a wire saw coal cutting device under a pseudo-inclined flexible shield support, applicable to the coal mining method described in any one of the first aspects, comprising: A drilling rig, used to arrange the boreholes to be drilled, preferably a core drilling rig; A wire saw with diamond bead wire saw cuts the coal seam between the boreholes to be cut using a reverse cutting method, thereby breaking the coal seam between the boreholes. The guide wheel assembly is used to guide and control the movement trajectory of the diamond wire saw. A traction device is installed in the return airway and is connected to the wire saw. The traction device pulls the wire saw to move on the pseudo-inclined coal mining face via a wire rope. Preferably, the traction device is an endless rope winch.

[0018] Compared with existing technologies, the technical effects achieved by this invention are as follows: 1. This invention constructs a pseudo-inclined coal mining face with an inclination angle of 25-30° between the return airway and the transport roadway, avoiding operation in steeply inclined areas, which greatly reduces the difficulty of construction and improves the convenience and safety of construction. 2. In the mining of steeply inclined coal seams, the arrangement of pseudo-inclined coal mining faces usually involves changes in the dip angle of the coal seam, or encounters with coal seam undulations and faults. However, this invention overcomes the influence of coal seam changes to the greatest extent by addressing both specific points and the overall situation. By using a diamond beaded wire saw to return to the coal seam, the cutting angle and direction of the wire saw can be adjusted to adapt to changes in the coal seam. 3. The wire saw of the present invention can move in the coal mining face, and the length of the coal seam to be mined can be determined according to the coal seam occurrence in the coal mining face. The position of the wire saw can be flexibly adjusted, and problems encountered in the cutting process can be dealt with in a timely manner. 4. The present invention uses wire sawing to cut coal seams, which is a non-impact cutting method. During the wire sawing process, vibration to the roof and coal wall can be reduced, thereby reducing the risk of roof collapse and side fall at the working face. 5. The diamond beads on the diamond wire saw of the present invention have high hardness, which can efficiently cut coal seams containing gangue or hard interlayers. Furthermore, the wire saw cutting trajectory is controllable, and it can accurately layer along the coal seam angle, reducing the cutting of the coal seam roof and floor, and improving the quality of the coal mined. 6. This invention uses wire saw cutting, which can cut continuously over long distances (up to tens of meters in a single cut), reducing the time for changing cutters and adjusting equipment, and improving mining efficiency. Furthermore, compared with traditional coal cutters or blasting methods, the diamond wire saw cutting method for coal seams consumes less energy due to its electric drive, and it eliminates the need for blasting material costs, making it more energy-efficient and environmentally friendly. 7. The wire saw cutting process of this invention has a strong water-carrying function, which can effectively suppress dust and generate no sparks, thereby reducing the risk of gas explosion. In summary, this invention combines flexibility, high efficiency, and safety, and can be widely used in the mining of steeply inclined coal seams. It has significant practical application value and solves the technical problems of low efficiency and high cost in the mining of steeply inclined coal seams in the prior art. Attached Figure Description

[0019] Figure 1 This is a flowchart of a method for cutting coal with a wire saw under a pseudo-inclined flexible shield support provided in one embodiment of the present invention; Figure 2 This is a schematic diagram of the pseudo-inclined coal mining face layout provided in one embodiment of the present invention; Figure 3 This is a schematic diagram of a wire saw cutting a coal seam provided in one embodiment of the present invention; Figure 4 This is a schematic diagram of a pseudo-inclined coal mining face provided in one embodiment of the present invention; Figure 5 This is a schematic diagram of a diamond beaded wire saw provided in one embodiment of the present invention; In the diagram: 1-Return air gate; 2-Return airway; 3-Cut-out; 4-Machine roadway; 5-Ventilation opening; 6-Pedestrian eye; 7-Coal chute; 8-Transport roadway; 9-Transport gate; 10-Coal seam; 11-Endless rope winch; 12-Endless rope; 13-Wire saw; 14-Drive wheel; 15-Second swivel wheel; 16-Diamond wire saw; 17-First swivel wheel; 18-First hydraulic telescopic rod; 19-Flexible shield support; 20-Enamel chute; 21-First directional... Guide wheel; 22-First borehole to be cut; 22a-First borehole to be cut A; 22b-First borehole to be cut B; 22n-First borehole to be cut N; 23-Second borehole to be cut; 23a-Second borehole to be cut A; 23b-Second borehole to be cut B; 23n-Second borehole to be cut N; 24-Second directional guide wheel; 25-Second hydraulic telescopic rod; 26-Wire rope; 27-Diamond abrasive grain; 28-Beads; 29-Isolation sleeve; 30-Top plate; 31-Bottom plate. Detailed Implementation

[0020] The technical solution of the present invention is described below with reference to the accompanying drawings and specific embodiments. It should be understood that the one or more steps mentioned in the present invention do not preclude the existence of other methods and steps before or after the combined steps, or that other methods and steps may be inserted between these explicitly mentioned steps. It should also be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the invention. Unless otherwise stated, the numbering of each method step is only for the purpose of identifying each method step, and not for limiting the order of each method or limiting the scope of the invention. Changes or adjustments to their relative relationships, without substantial changes to the technical content, can also be considered within the scope of the present invention.

[0021] The raw materials and instruments used in the examples are not subject to any specific restrictions on their source; they can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0022] Example: This invention provides a method for wire sawing coal under a pseudo-inclined flexible shield support. This method is used for mining steeply inclined coal seams and solves the technical problems of low efficiency and high cost in the prior art for mining steeply inclined coal seams.

[0023] like Figures 1-5 As shown, in one embodiment, the wire saw coal cutting method under the pseudo-inclined flexible shield support includes the following steps: Step S1: A return airway 2 is constructed on the upper horizontal surface of the steeply inclined coal seam, and a transport airway 8 is constructed on the lower horizontal surface. A pseudo-inclined mining face with an inclination angle of 25-30° is arranged on the coal seam 10 between the return airway 2 and the transport airway 8. Multiple boreholes are arranged according to the occurrence of coal seam 10 in the pseudo-inclined mining face, avoiding steeply inclined coal seams with a true dip angle greater than 45°, and a pseudo-inclined mining face with an inclination angle of 25-30° is constructed within the steeply inclined coal seam. The mining section formed by the pseudo-inclined mining face is supported by a flexible shield support 19. The shape of the mining section is not limited, but a quadrilateral shape is preferred; more preferably, the mining section is approximately rectangular. Coal mining is carried out using a diamond wire saw within the support range of the flexible shield support 19. A return air gate 1 is provided in the return airway 2, mainly used to discharge sludge (containing methane, coal dust, carbon dioxide, etc.).

[0024] Since most of the return airway 2 and transport airway 8 are coal-passing roadways arranged along the coal seam, in order to connect the return airway 2 and transport airway 8 in a section, a pseudo-dip angle channel with an inclination angle of 25~30° needs to be arranged in the section. This channel is called cut-in 3. Therefore, cut-in 3 achieves the purpose of connecting return airway 2 and transport airway 8, and the coal mining face is arranged on cut-in 3. Figure 2As shown, the upper end of the pseudo-inclined coal face cut-off 3 connects to the return airway 2, while the lower end connects to the machine roadway 4. Coal seam mining is carried out in sections. The main function of the return airway 2 is to exhaust polluted air from the working face. The machine roadway 4 is a separate, single-ended roadway, mainly used for supplying air to the working face and laying chutes. The transport roadway 8 is mainly used for supplying air to the working face and transporting coal. When a section of the coal seam is mined out, the transport roadway of that section becomes the return airway for the next coal face section. The machine roadway 4 has three small openings: a coal chute opening 7, a pedestrian opening 6, and a ventilation opening 5. The other end of the small openings in the machine roadway 4 connects to one end of the transport roadway 8. The other end of the transport roadway 8 is equipped with a transport gate 9, mainly used for transporting out coal and gangue, and for transporting in materials, equipment, and fresh air. Figure 3 As shown, a flexible shield support 19 is installed inside the cut eye 3 of the pseudo-inclined coal mining face. Within the support range of the flexible shield support 19, a wire saw 13, a first borehole to be cut 22, a second borehole to be cut 23, a first hydraulic telescopic rod 18, a second hydraulic telescopic rod 25, a first universal wheel 17, a second universal wheel 15, and an enamel chute 20 are arranged. In some embodiments, the selection of the flexible shield support 19 is determined according to the thickness of the coal seam, which is determined by geological borehole exploration.

[0025] A first directional guide wheel 21 is fixed to the bottom of the first hydraulic telescopic rod 18. Preferably, the first directional guide wheel 21 is fixed at the lower 4 / 5 position of the first hydraulic telescopic rod 18. A second directional guide wheel 24 is fixed to the lower end of the second hydraulic telescopic rod 25. Preferably, the second directional guide wheel 24 is fixed at the lower 4 / 5 position of the second hydraulic telescopic rod 25. This position is chosen mainly to reserve rotation space for the guide wheel, which can ensure that the coal seam is cut deeper and that the guide wheel can rotate normally. If it is fixed to the bottom, it may be affected by torque during the cutting process. The contact between the bottom end of the hydraulic telescopic rod and the coal seam will reduce the influence of torque.

[0026] like Figures 2-3 As shown, the first borehole 22 and the second borehole 23 are constructed using a drilling rig (e.g., a coring drill) starting from the intersection of the coal chute 7 and the pseudo-inclined coal face cut-out 3, proceeding from bottom to top at intervals. l (For example, the distance between the first drill hole 22 and the second drill hole 23) l Construction of a group of boreholes to be drilled, such as Figure 4 The first borehole to be cut, A 22a, B 22b, ..., N 22n, followed by the second borehole, A 23a, B 23b, ..., N 23n, and so on, until it reaches the intersection of the return airway 2 and the pseudo-inclined coal face cutting point 3. The number of boreholes in a group is... n , n Based on the distance between the top plate 30 and the bottom plate 31 of the coal seam bIt is determined that the distance between the boreholes to be cut in the same group is b1. n and b The relationship between them is n = b / b1, for example, the distance between the second drill hole A 23a and the second drill hole B 23b is 200mm. n = b / 200, the size of the hole to be drilled is d180mm (diameter) × H1000mm (height). After the hole to be drilled is completed, an easy-cutting body with a size of d178mm × H1000mm is inserted. The function of the easy-cutting body is to prevent the hole to be drilled from collapsing. In some embodiments, the easy-cutting body includes a plastic PVC pipe.

[0027] Step S2: Using a traction device (e.g., an endless rope winch), the wire saw is moved to the pseudo-inclined coal mining face, and the diamond beaded wire saw is used to cut the coal seam between the boreholes to be cut based on the reverse cutting method; wherein, the diamond beaded wire saw includes a wire rope 26, an isolation sleeve 29 sleeved on the wire rope 26, beads 28 fixed on the isolation sleeve 29, and diamond abrasive grains 27 embedded in the beads 28.

[0028] Step S3: Transfer the crushed coal formed after the coal seam is cut into the mining area transportation device.

[0029] In some embodiments, transferring the crushed coal formed after coal seam cutting into the mining area transportation device includes: First, the crushed coal formed after the coal seam is cut is scooped onto both sides of the roof 30 and the floor 31, and then an enamel chute 20 is laid on it. Next, the crushed coal is scooped onto the enamel chute 20 and, by its own weight, flows through the enamel chute 20 into the coal chute 7. The coal chute 7 directly transfers the crushed coal into the scraper conveyor in the transport roadway and then onto the belt conveyor in the transport roadway. Finally, the crushed coal enters the mining area transport device.

[0030] In some embodiments, after the broken coal formed by cutting the coal seam is transferred to the mining area transportation device, the method further includes: after the coal seam between the boreholes to be cut is mined, a flexible shield support 19 is lowered and the next section of coal seam is mined using the reverse cutting method.

[0031] like Figure 3 In some embodiments, using a diamond wire saw to cut the coal seam between boreholes based on a reverse cutting method includes: Step S21: Adjust the angles of the first directional guide wheel 21 and the second directional guide wheel 24 so that the angles of the first directional guide wheel 21 and the second directional guide wheel 24 are the same as the angles of the first drill hole 22 and the second drill hole 23 to be cut, and are respectively aligned with the first drill hole 22 and the second drill hole 23 to be cut. Step S22: The diamond wire saw 16 is passed around the first directional guide wheel 21 and the second directional guide wheel 24 respectively. The first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25 (as position adjustment devices) are used to insert the first directional guide wheel 21 and the second directional guide wheel 24 into the first drill hole 22 and the second drill hole 23 to be cut. After reaching the pre-cut position, the first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25 are fixed. The diamond wire saw 16 is then guided to pass around the second directional guide wheel 24, the first directional guide wheel 21, the first universal wheel 17, the second universal wheel 15, the drive wheel 14, and the tensioning part of the wire saw machine 13 respectively. Step S23: Determine the reverse cutting circuit and check that the diamond bead wire saw 16 fits into each guide wheel groove. Step S24: Start the wire saw 13 to cut the coal seam between the boreholes evenly. At the same time, through the wire saw 13’s wire winding function, keep the diamond bead wire saw 16 taut and continue to cut the steeply inclined coal seam to complete the reverse cutting process. The reverse cutting circuit, according to the cutting route, is as follows: wire saw 13 tensioning part, drive wheel 14, coal body, second directional guide wheel 24, target coal body, first directional guide wheel 21, first universal wheel 17, second universal wheel 15, drive wheel 14, wire saw 13 tensioning part; After the diamond bead wire saw 16 forms a closed loop, the position and tensioning part of the wire saw machine 13 need to be adjusted to keep the diamond bead wire saw 16 in a tensioned state. After the diamond beaded wire saw cuts to the pre-cut position, adjust the tension of the wire saw machine 13 and withdraw the diamond beaded wire saw 16 along the original path.

[0032] like Figure 4 As shown, in some embodiments, mining a pseudo-inclined coal face includes: Step S221: Arrange the first borehole 22 and the second borehole 23 to be cut according to the coal seam occurrence conditions; Step S222: Adjust the angle of the hydraulic telescopic rod so that the first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25 can extend into the corresponding first drill hole A 22a and second drill hole A 23a to be cut. The angles of the first directional guide wheel 21 and the second directional guide wheel 24 are the same as the angles of the first drill hole A 22a and the second drill hole A 23a to be cut, and are respectively aligned with the first drill hole A 22a and the second drill hole A 23a to be cut. The diamond wire saw 16 is simultaneously wrapped around the first directional guide wheel 21 and the second directional guide wheel 24. The first directional guide wheel 21 and the second directional guide wheel 24 are extended into the first drill hole A 22a and the second drill hole A 23a to be cut using the first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25. After the first directional guide wheel 21 and the second directional guide wheel 24 reach the pre-cut position, the first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25 are fixed. Step S223: Adjust the positions of the first omnidirectional wheel 17, the second omnidirectional wheel 15 and the drive wheel 14 so that the grooves of the first omnidirectional wheel 17, the second omnidirectional wheel 15 and the drive wheel 14 are in the same straight line as the grooves of the first directional guide wheel 21 and the second directional guide wheel 24. Step S224: The diamond beaded wire saw 16 on the ground is passed around the grooves of the first universal wheel 17, the second universal wheel 15 and the drive wheel 14 respectively, and the position and tensioning part of the wire saw machine 13 are adjusted so that the diamond beaded wire saw 16 is in a tensioned state. Step S225: Start the wire saw and cut the coal seam between the first borehole A 22a and the second borehole A 23a at a uniform speed. Through the automatic wire winding function of the wire saw 13, the diamond bead wire saw 16 is continuously tensioned to achieve downward cutting to the pre-cut position. Step S226: Start the rope release function of the wire saw 13 to make the diamond bead wire saw 16 slack. Take out the first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25, move the first hydraulic telescopic rod 18 and the second hydraulic telescopic rod 25 to the corresponding first drill hole B 22b and second drill hole B 23b to be cut, and repeat steps S221 to S225 until the coal seam between the first drill hole 22 and the second drill hole 23 is cut and broken. In step S227, the broken coal in the middle of the flexible shield support 19 is scooped onto both sides of the roof 30 and the bottom 31, and then the enamel chute 20 is laid on it. The broken coal is then scooped onto the enamel chute 20 and, by its own weight, flows through the enamel chute 20 into the coal chute 7 in the working face. The coal chute 7 is directly transferred to the scraper conveyor in the transport roadway and then transferred to the belt conveyor in the transport roadway to enter the mining area transport device. Step S228: After the coal seam in the area cut by the diamond wire saw is mined, the flexible shield support 19 is slowly lowered to complete one mining cycle. The endless rope winch 11 is used to pull the wire saw 13 to the next mining area through the endless rope 12 to start the next mining cycle. Steps S221 to S228 are repeated. Single cycle output P The specific calculation formula is as follows:

[0033] P 1 represents the output per cycle. l For the length of the cutting working surface, h For cutting depth, γ The bulk density of coal, b The working face mining width, c The recovery rate of the working face is taken as 95%.

[0034] The formula for calculating the annual output of coal mining face is as follows:

[0035] P This indicates the annual output of the working face. n This refers to the number of daily cycles for the working face. w The number of working days per year; generally 330 days is taken. η The effective cycle rate is set to 80%, and P1 is the output per cycle.

[0036] Taking the C6 coal seam in a certain coal mine's No. 1 mining area as an example, the average depth of the coal seam in the working face is 1.85m, and the dip angle is 65°. The production capacity of the working face using diamond wire saw cutting pseudo-inclined flexible shield support mining technology is as follows: In the test phase, the pseudo-inclined coal mining working face has an dip angle of 26°, the wire saw cuts a coal seam length of 15m, a cutting depth of 0.80m, and the coal's bulk density γ is 1.42. It takes about 3 hours to complete one mining process cycle, with 8 cycles per day.

[0037] Single cycle output P The specific calculation formula is as follows:

[0038] The annual output of coal mining face is: .

[0039] In some embodiments, the present invention provides a wire saw coal cutting device under a pseudo-inclined flexible shield support, applicable to the above-mentioned wire saw coal cutting method under a pseudo-inclined flexible shield support, comprising: a core drilling rig, a wire saw with diamond bead wire saw, a guide wheel assembly, and an endless wire winch.

[0040] The coring drill is set up in the pseudo-inclined coal mining face; the wire saw with diamond bead wire saw cuts the coal seam between the boreholes to be cut using the reverse cutting method, which breaks the coal seam between the boreholes; the guide wheel set (including universal wheel set and guide wheel) is used to guide and control the movement trajectory of the diamond bead wire saw; the endless rope winch is set up in the return airway, and the endless rope winch is connected to the wire saw. The endless rope winch pulls the wire saw to move on the pseudo-inclined coal mining face through the wire rope.

[0041] In steeply inclined coal seam mining, the pseudo-inclined coal face usually has changes in the dip angle of the coal seam, or encounters coal seam undulations and faults. However, in this invention, the diamond beaded wire saw can adapt to changes in the coal seam by adjusting the cutting angle and direction of the wire saw. The diamond abrasive grains 27 on the diamond wire saw of the present invention have high hardness, which can efficiently cut coal seams containing gangue or hard interlayers, and the wire saw cutting trajectory is controllable, which can accurately layer along the coal seam angle, reduce the cutting of the coal seam roof and floor, and improve the quality of coal mined. The present invention uses wire sawing to cut coal seams, which is a non-impact cutting method. During the wire sawing process, vibration to the roof and coal wall can be reduced, thereby reducing the risk of roof collapse and side fall at the working face. This invention uses wire saw cutting, which enables long-distance continuous cutting (a single cut can reach tens of meters), reducing the time for changing cutters and adjusting equipment, and improving mining efficiency. Furthermore, compared with traditional coal cutters or blasting methods, the diamond wire saw for cutting coal seams has lower energy consumption due to its electric drive, and it eliminates the need for blasting material costs. The wire saw cutting process of this invention has a strong water-carrying function, which can effectively suppress dust and generate no sparks, thereby reducing the risk of gas explosion. In summary, this invention combines flexibility, high efficiency, and safety, and can be widely used in the mining of steeply inclined coal seams. It has significant practical application value and solves the technical problems of low efficiency and high cost in the mining of steeply inclined coal seams in the prior art.

[0042] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A method for wire sawing coal under a pseudo-inclined flexible shield support, characterized in that, include: Multiple boreholes to be cut are arranged in a pseudo-inclined coal mining face. The pseudo-inclined coal mining face is a coal mining face with an inclination angle of less than 45° arranged between the return airway and the transport roadway. The pseudo-inclined coal mining face is supported by a flexible shield support to form a coal mining section. The average actual inclination angle of the coal seam in the coal mining section is greater than 45°. The wire saw is moved to the pseudo-inclined coal mining face using a traction device, and the coal seam between the boreholes to be cut is cut using a diamond wire saw based on the reverse cutting method. The crushed coal formed after the coal seam is cut is transferred to the mining area transportation device.

2. The method for wire sawing coal under a pseudo-inclined flexible shield support according to claim 1, characterized in that, The pseudo-inclined coal mining face is a coal mining face with an inclination angle of 25-30° arranged between the return airway and the transport roadway.

3. The method for wire sawing coal under a pseudo-inclined flexible shield support according to claim 1, characterized in that, Multiple boreholes to be drilled are arranged in the pseudo-inclined coal mining face, including: A drilling rig is used to construct a set of boreholes to be cut at regular intervals on the coal face. Each regular interval is the length of a single cut made by the wire saw. l The number of boreholes to be cut in a group is n, the distance between each group of boreholes to be cut is the distance that the coal seam can be broken after the wire saw cuts, and the diameter of the boreholes to be cut is d.

4. The method for wire sawing coal under a pseudo-inclined flexible shield support according to claim 1, characterized in that, Cutting the coal seam between the boreholes using a diamond wire saw based on the reverse cutting method includes: The diamond wire saw is wound around the directional guide wheel, and the directional guide wheel is extended into the hole to be cut by the position adjustment device. After reaching the pre-cut position, the position adjustment device is fixed. Adjust the positions of the caster wheel, the directional guide wheel, and the drive wheel, and then pass the diamond bead wire saw around the grooves of the caster wheel, the directional guide wheel, and the drive wheel respectively. Adjust the position and tension of the wire saw machine so that the diamond bead wire saw is in a tensioned state and can cut normally. Start the wire saw machine. Through the high-speed rotation of the wire saw machine drive wheel and the automatic wire winding function, the diamond bead wire saw is driven by the wire saw machine drive wheel to be in a high-speed stepless rotation and continuous tension state, cutting the coal seam between the boreholes to be cut, so as to achieve the purpose of the diamond bead wire saw cutting downward to the pre-cut position. Start the wire saw machine, and use the wire release function of the wire saw machine to make the diamond bead wire saw in a slack state. Take out the position adjustment device, move the position adjustment device to the next set of holes to be cut, and repeat the above cutting operation of the holes to be cut until the coal seam between all the holes to be cut is cut and broken.

5. The method for wire sawing coal under a pseudo-inclined flexible shield support according to claim 4, characterized in that, The position adjustment device includes a hydraulic telescopic rod.

6. The method for wire sawing coal under a pseudo-inclined flexible shield support according to claim 1, characterized in that, The equipment for transferring the crushed coal formed after cutting the coal seam into the mining area includes: First, the crushed coal formed after the coal seam is cut is scooped onto both sides of the top and bottom plates of the coal seam, and then an enamel chute is laid. Next, the crushed coal is scooped onto the enamel chute and, by its own weight, flows through the enamel chute into the coal chute. The coal chute directly transfers the crushed coal into the scraper conveyor in the transport roadway, and then onto the belt conveyor in the transport roadway. Finally, the crushed coal enters the mining area transport device.

7. The method for wire sawing coal under a pseudo-inclined flexible shield support according to claim 1, characterized in that, After the broken coal formed by cutting the coal seam is transferred to the mining area transportation device, the process also includes: after the coal seam between the boreholes to be cut is mined, the flexible shield support is lowered, and the reverse cutting method is used to continue mining the next section of the coal seam.

8. A wire saw coal cutting device under a pseudo-inclined flexible shield support, characterized in that, The method for wire sawing coal under a pseudo-inclined flexible shield support as described in any one of claims 1-7 includes: A wire saw with diamond bead wire saw cuts the coal seam between the boreholes to be cut using a reverse cutting method, thereby breaking the coal seam between the boreholes. The guide wheel assembly is used to guide and control the movement trajectory of the diamond wire saw. A traction device is installed in the return airway. The traction device is connected to the wire saw and pulls the wire saw to move on the pseudo-inclined coal mining face via a wire rope.

Images