A device for processing a support frame of a fully mechanized coal mining face and a method thereof

Abstract

A device and method for handling frame compression in fully mechanized mining faces include a support frame, a scraper conveyor, and a transport roadway. The support frame is positioned in front of the coal face in the mining area; the scraper conveyor is positioned below the support frame and hinged to its push-pull head; the transport roadway is located on one side of the support frame; the frame compression cutting area is located above the support frame; a roadway is constructed on the side of the coal face, below the frame compression cutting area, and in front of the support frame; the length of the roadway is greater than or equal to the frame compression cutting area; and anchor bolt mesh support is installed on the roadway roof and sidewalls. The method employs four working steps: coal face roadway construction, roadway support, scraper conveyor and support base placement, and push-pull frame operation. This invention effectively solves the frame compression problem in fully mechanized mining faces and has advantages such as safety, reliability, simple construction, and low investment cost.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and in particular to a device and method for dealing with the pressure on the frame of a fully mechanized mining face. Background Technology

[0002] With economic and technological development, fully mechanized coal mining technology has been rapidly promoted in my country's coal industry. Hydraulic supports, as one of the important pieces of equipment in fully mechanized coal mining, are used to maintain the roof of the coal face, such as coal mining machines and scraper conveyors. They bear the important tasks of controlling and managing the roof, maintaining normal working space, and protecting personnel and equipment, thus maximizing the safety of life in coal mines. However, hydraulic supports encounter various problems in actual operation at fully mechanized coal mining faces, such as the "support pressure" phenomenon. The "support pressure" phenomenon occurs when, as the coal seam is gradually mined, the roof pressure increases, and the load on the supports also gradually increases. This pressure comes from two aspects: the pressure from the immediate roof and the pressure formed by the existing roof. When the coal mining machine has mined a certain depth, the supports move forward one step to support the newly exposed roof. If the roof breaks, sinks, or fractures (roof cutting before the support), the load on the supports increases until the pressure in the lower cavity of the support column reaches the safety valve's set value. The safety valve releases, the column retracts, and due to insufficient remaining stroke, the support experiences the "support pressure" phenomenon. When a "roof collapse" occurs, the commonly used methods include roof lifting, bottom removal, and loosening blasting. Roof lifting can easily induce roof falls, and workers are exposed to an open roof, potentially leading to injuries or fatalities. Bottom removal involves limited working space and high labor intensity. Loosening and blasting involves blasting operations, increasing risks and yielding poor results. Improper handling can also cause significant economic losses or personal injury accidents, such as roof falls at the working face, prolonged production stoppages, and difficulties in equipment retraction. Summary of the Invention

[0003] To address the aforementioned problems, this invention proposes a device for handling the pressure on the roof of a fully mechanized mining face, comprising a support, a scraper conveyor, and a transport roadway. The support is positioned in front of the coal face in the mining area; the scraper conveyor is positioned below the support and hinged to the support's push-pull head; the transport roadway is located on one side of the support; the roof-cutting area is located above the support; a roadway is constructed on the side of the coal face, below the roof-cutting area, and in front of the support; the length of the roadway is greater than or equal to that of the roof-cutting area; and anchor bolt mesh supports are installed on the roadway roof and sidewalls. The anchor bolt mesh includes anchor bolts and mesh panels, which overlap and are connected by wire binding. The anchor bolts are driven into the overlapping areas of the mesh panels.

[0004] Furthermore, the anchor bolts include at least two evenly arranged roadway roof anchor bolts and at least two evenly arranged roadway sidewall anchor bolts, and the mesh includes a roadway roof mesh and a roadway sidewall mesh.

[0005] Furthermore, the driving angle of the roadway roof anchor bolts is as follows: the angle between the roadway roof anchor bolts near the sidewall and the roadway roof is 70° to 80°, and the remaining roadway roof anchor bolts are perpendicular to the roadway roof. The roadway roof anchor bolts are spaced 900mm apart, with a row spacing of 800mm, and have a specification of φ20×2200mm, arranged in a square grid pattern. The ends of the roadway roof anchor bolts are made of left-handed high-strength threaded steel without longitudinal ribs, and are equipped with butterfly trays, spherical washers, and damping pads. The butterfly trays are 120×120mm in size and 10mm thick, and are anchored using anchoring agent. The roadway roof mesh is a metal diamond mesh woven from iron wire, woven with #10 iron wire, with a specification of 1800×3000mm. The overlap between the roadway roof mesh panels is 200mm, and the overlap is connected by double-strand #14 iron wire double-strand double-row buckles, with a buckle spacing of 200mm.

[0006] Furthermore, the driving angle of the roadway sidewall anchors is as follows: those near the roadway top slab form an upward angle of 70°–80° with the roadway sidewall; those near the bottom slab form a downward angle of 70°–80° with the sidewall; the remaining roadway sidewall anchors are perpendicular to the roadway sidewall. The roadway sidewall anchors are φ18×1800mm in size, arranged in a grid pattern with a spacing of 900mm and a row spacing of 800mm. The ends of the roadway sidewall anchors... Fiberglass anchor bolts are used, along with butterfly trays, spherical washers, and damping pads. The butterfly trays are 120×120mm in size and 10mm thick, and are anchored using an anchoring agent. The tunnel sidewall mesh is a flame-retardant plastic mesh with steel wire, measuring 2600×10000mm in size and with a mesh size of 50×50mm. The tunnel sidewall meshes overlap by 200mm, and the overlaps are connected by double-stranded 14# iron wire with double-stranded double-row buckles.

[0007] Furthermore, wooden strips are placed between the front beam of the support and the roof of the tunnel for filling.

[0008] This invention also proposes a method for dealing with the pressure on the support frame in a fully mechanized mining face. The method employs the aforementioned coal face side-opening device for handling the pressure on the support frame in a fully mechanized mining face. The method consists of four steps: coal face opening, roadway support, scraper conveyor and support base placement, and pushing and pulling the support frame. The specific steps are as follows:

[0009] 1) Coal wall excavation: A roadway is gradually excavated on the side of the coal wall in the roof-cutting area by widening the sidewall. The roadway starts from the coal wall on the side of the transport roadway and the excavation length is greater than or equal to that of the roof-cutting area.

[0010] 2) Roadway support: The roadway is supported on the top and side walls by anchor bolt mesh to prevent coal breakage and roof collapse, and to ensure the safety of the roadway. The anchor bolt mesh includes anchor bolts and mesh panels. The mesh panels overlap and are connected by wire at the overlap. The anchor bolts are driven into the overlapping parts of the mesh panels.

[0011] 3) Scraper conveyor and support base plate: Drill shallow blast holes at the base plate in front of the support base and blast with explosives; after blasting, remove the broken rocks to lower the scraper conveyor and support base, and allow the support column to recover a small amount of travel.

[0012] 4) Push-pull frame: Extend the support push-pull head and slowly push the scraper conveyor towards the roadway, causing the scraper conveyor to slowly land; after the scraper conveyor lands, install the pressure column to fix it; then, retract the support push-pull head, driving the support to move towards the roadway; remove the pressure column, extend the support push-pull head again, and continue to slowly push the scraper conveyor towards the roadway, install the pressure column again to fix it, retract the support push-pull head, and drive the support to move; repeat the above steps several times until the scraper conveyor and the support move to the roadway, completing the process of handling the pressure column. The movement distance of the scraper conveyor and the support is controlled at 200-300mm each time.

[0013] Furthermore, the anchor bolts include at least two evenly arranged roadway roof anchor bolts and at least two evenly arranged roadway sidewall anchor bolts, and the mesh includes a roadway roof mesh and a roadway sidewall mesh.

[0014] Furthermore, the driving angle of the roadway roof anchor bolts is as follows: the angle between the roadway roof anchor bolts near the sidewall and the roadway roof is 70° to 80°, and the remaining roadway roof anchor bolts are perpendicular to the roadway roof. The roadway roof anchor bolts are spaced 900mm apart, with a row spacing of 800mm, and have a specification of φ20×2200mm, arranged in a square grid pattern. The ends of the roadway roof anchor bolts are made of left-handed high-strength threaded steel without longitudinal ribs, and are equipped with butterfly trays, spherical washers, and damping pads. The butterfly trays are 120×120mm in size and 10mm thick, and are anchored using anchoring agent. The roadway roof mesh is a metal diamond mesh woven from iron wire, woven with #10 iron wire, with a specification of 1800×3000mm. The overlap between the roadway roof mesh panels is 200mm, and the overlap is connected by double-strand #14 iron wire double-strand double-row buckles, with a buckle spacing of 200mm.

[0015] Furthermore, the driving angle of the roadway sidewall anchors is as follows: those near the roadway top slab form an upward angle of 70°–80° with the roadway sidewall; those near the bottom slab form a downward angle of 70°–80° with the sidewall; the remaining roadway sidewall anchors are perpendicular to the roadway sidewall. The roadway sidewall anchors are φ18×1800mm in size, arranged in a grid pattern with a spacing of 900mm and a row spacing of 800mm. The ends of the roadway sidewall anchors... Fiberglass anchor bolts are used, along with butterfly trays, spherical washers, and damping pads. The butterfly trays are 120×120mm in size and 10mm thick, and are anchored using an anchoring agent. The tunnel sidewall mesh is a flame-retardant plastic mesh with steel wire, measuring 2600×10000mm in size and with a mesh size of 50×50mm. The tunnel sidewall meshes overlap by 200mm, and the overlaps are connected by double-stranded 14# iron wire with double-stranded double-row buckles.

[0016] Furthermore, wooden strips are placed between the front beam of the support and the roof of the tunnel for filling.

[0017] The beneficial effects of this invention are: it solves the problem of support frame compression in fully mechanized mining faces, is safe and reliable, easy to construct, and low in cost, effectively avoiding the risks associated with traditional methods such as roof lifting, bottom lifting, and loosening blasting to solve the support frame compression problem; traditional methods, such as roof lifting to deal with support frame compression, are prone to inducing roof collapse, and workers are exposed to the open roof, which may lead to casualties; the bottom lifting method to deal with support frame compression has a small working space and high labor intensity; loosening blasting to deal with support frame compression involves blasting operations, which increases the risk and has poor results. If not handled properly, it can also cause significant economic losses or personal injury accidents such as roof collapse, long-term shutdown, and difficulty in equipment withdrawal.

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 This is a schematic front view of the pressure frame device for the fully mechanized mining face of the present invention.

[0020] Figure 2 This is a top view schematic diagram of the fully mechanized mining face pressure frame device of the present invention.

[0021] Figure 3 This is a schematic diagram of the coal face side-opening anchor mesh support of the present invention.

[0022] Figure 4 This is a schematic front view (b) of the fully mechanized mining face pressure frame device of the present invention.

[0023] Figure 5 This is a schematic diagram of the scraper conveyor and the base plate of the support of the present invention.

[0024] Figure 6 This is a schematic diagram of the traction moving support of the present invention.

[0025] Figure 7 This is a schematic diagram (b) of the traction moving support of the present invention.

[0026] Figure 8 This is a schematic diagram (c) of the traction moving support of the present invention. Detailed Implementation

[0027] Example 1: Figures 1 to 8 As shown, a device for handling the pressure on the longwall face of a fully mechanized mining face includes a support 1, a scraper conveyor 2, and a transport roadway 3. The support 1 is positioned in front of the coal wall 5 in the mining area. The scraper conveyor 2 is positioned below the support 1 and hinged to a support push-pull head 101. The transport roadway 3 is located on one side of the support 1. A pressure-cutting area 4 is located above the support 1. A roadway 6 is opened on the side of the coal wall 5, below the pressure-cutting area 4, and in front of the support 1. The length 601 of the roadway is greater than or equal to the pressure-cutting area 4. Anchor bolt mesh supports are installed on the roadway roof and sidewalls. The anchor bolt mesh includes anchor bolts and mesh panels, which overlap and are connected by wire at the overlap. The anchor bolts are driven into the overlapping areas of the mesh panels.

[0028] Example 2: Based on Example 1, as follows Figure 2 , Figure 3 As shown, the anchor bolts include at least two evenly arranged roadway roof anchor bolts 701 and at least two evenly arranged roadway sidewall anchor bolts 702, and the mesh includes a roadway roof mesh 801 and a roadway sidewall mesh 802.

[0029] Example 3: Based on the above examples, such as... Figures 1 to 8As shown, the driving angle of the roadway roof anchor bolt 701 is as follows: Based on the coal seam conditions of the roadway roof described in this embodiment, in order to ensure the bearing capacity of the anchor bolt, the angle 12 between the roadway roof anchor bolt 701 near the sidewall and the roadway roof is 70° to 80°, with 75° being optimal. The remaining roadway roof anchor bolts 701 are perpendicular to the roadway roof. The spacing 703 of the roadway roof anchor bolts 701 is 900mm, the row spacing 704 is 800mm, and the specifications are φ20×2200mm, arranged in a square grid pattern. The ends of the roadway roof anchor bolts 701 are made of left-handed high-strength threaded steel without longitudinal ribs, and are equipped with a butterfly tray, a spherical washer, and a damping pad to increase the anchor bolt's strength. For load-bearing performance, the butterfly-shaped pallet has a size of 120×120mm and a thickness of 10mm. Each anchor bolt uses one roll of MSCK-2370 anchoring agent, with an anchoring force of not less than 80kN and a torque of 100N·m, ensuring the safety of the roof. The tunnel roof mesh 801 is a metal diamond mesh woven from 10# iron wire, with a size of 1800×3000mm. The tunnel roof mesh 801 overlaps with a 200mm joint, and the overlaps are connected by double-strand 14# iron wire double-strand double-row buckles with a buckle spacing of 200mm. The metal diamond mesh has higher strength and better tensile strength, providing better protection for the tunnel roof.

[0030] Example 4: Based on the above examples, such as... Figures 1 to 8 As shown, based on the coal seam conditions of the roadway roof described in this embodiment, to ensure the bearing capacity of the anchor bolts, the driving angle of the roadway sidewall anchor bolts 702 is as follows: for those near the roadway roof, the upward angle 12 with the roadway sidewall is 70°–80°, with 75° being optimal; for those near the floor, the downward angle 12 with the sidewall is 70°–80°, with 75° being optimal. The remaining roadway sidewall anchor bolts 702 are perpendicular to the roadway sidewall and arranged in a grid pattern. The spacing 703 of the roadway sidewall anchor bolts 702 is 900mm, and the row spacing 704 is 800mm. The specifications of the roadway sidewall anchor bolts 702 are φ18×1800mm. The ends of the sidewall anchor bolts 702 are made of fiberglass to increase their strength. They are also equipped with butterfly trays, spherical washers, and damping pads to enhance their load-bearing capacity. The butterfly trays are 120×120mm in size and 10mm thick. Each anchor bolt uses one roll of CK-2370 anchoring agent, with an anchoring force of 40kN and a torque of 40N·m. The tunnel sidewall mesh 802 is a flame-retardant plastic mesh with steel wire, measuring 2600×10000mm with a mesh size of 50×50mm. The tunnel sidewall mesh 802 overlaps with a 200mm seam, and the overlaps are connected by double-stranded 14# iron wire with double-strand double-row buckles.

[0031] Example 5: Based on the above examples, such as... Figures 4 to 8As shown, wooden strips 11 are placed between the front beam 104 of the support 1 and the roof of the tunnel to prevent the support 1 from becoming unstable during movement due to the increased space between the front beam 104 and the roof 601.

[0032] Example 6: Based on the above examples, such as... Figures 1 to 8 As shown, a method for handling the pressure on the support frame in a fully mechanized mining face is described. The method involves four steps: coal face opening, roadway support, scraper conveyor and support base laying, and pushing and pulling the support frame. The specific steps are as follows:

[0033] 1) Coal wall roadway opening: A roadway 6 is gradually opened on the side of the coal wall 5 in the roof-cutting zone 4 by widening the side walls. The roadway 6 starts from the coal wall on the side of the transport roadway 3, and the excavation length 601 is greater than or equal to that of the roof-cutting zone 4.

[0034] 2) Roadway support: The roadway 6 is supported on the top and side walls by anchor bolt mesh to prevent coal breakage and roof collapse, and to ensure the safety of the roadway. The anchor bolt mesh includes anchor bolts and mesh panels. The mesh panels overlap and are connected by wire at the overlap. The anchor bolts are driven into the overlapping parts of the mesh panels.

[0035] 3) Scraper conveyor and support base plate: Drill shallow blast holes at the base plate 9 in front of the support base 102, load a small amount of explosives and blast; after blasting, remove the broken rocks, so that the scraper conveyor 2 and support base 102 can be lowered, and the support column 103 can resume a small amount of travel.

[0036] 4) Pushing and pulling the frame: Extend the support push-pull head 101 and slowly push the scraper conveyor 2 towards the roadway 6, causing the scraper conveyor 2 to slowly land; after the scraper conveyor 2 lands, apply the pressure column 10 to fix it; then, retract the support push-pull head 101, driving the support 1 to move towards the roadway 6; remove the pressure column 10, and the support 1 extends the support push-pull head 101 again, continuing to slowly push the scraper conveyor 2 towards the roadway 6, applying the pressure column 10 to the scraper conveyor 2 again to fix it, retract the support push-pull head 101, and drive the support 1 to move; after repeating the above steps several times, the scraper conveyor 2 and the support 1 move to the roadway 6, completing the process of handling the pressure frame. The distance that the scraper conveyor 2 and the support 1 move each time is controlled within 200-300mm.

[0037] Example 7: Based on the above examples, such as... Figures 1 to 8 As shown, the anchor bolts include at least two evenly arranged roadway roof anchor bolts 701 and at least two evenly arranged roadway sidewall anchor bolts 702, and the mesh includes a roadway roof mesh 801 and a roadway sidewall mesh 802.

[0038] Example 8: Based on the above examples, as follows... Figures 1 to 8 As shown, the driving angle of the roadway roof anchor bolt 701 is as follows: Based on the coal seam conditions of the roadway roof described in this embodiment, in order to ensure the bearing capacity of the anchor bolt, the angle 12 between the roadway roof anchor bolt 701 near the sidewall and the roadway roof is 70° to 80°, with 75° being optimal. The remaining roadway roof anchor bolts 701 are perpendicular to the roadway roof. The spacing 703 of the roadway roof anchor bolts 701 is 900mm, the row spacing 704 is 800mm, and the specifications are φ20×2200mm, arranged in a square grid pattern. The ends of the roadway roof anchor bolts 701 are made of left-handed high-strength threaded steel without longitudinal ribs, and are equipped with a butterfly tray, a spherical washer, and a damping pad to increase the anchor bolt's strength. For load-bearing performance, the butterfly-shaped pallet has a size of 120×120mm and a thickness of 10mm. Each anchor bolt uses one roll of MSCK-2370 anchoring agent, with an anchoring force of not less than 80kN and a torque of 100N·m, ensuring the safety of the roof. The tunnel roof mesh 801 is a metal diamond mesh woven from 10# iron wire, with a size of 1800×3000mm. The tunnel roof mesh 801 overlaps with a 200mm joint, and the overlaps are connected by double-strand 14# iron wire double-strand double-row buckles with a buckle spacing of 200mm. The metal diamond mesh has higher strength and better tensile strength, providing better protection for the tunnel roof.

[0039] Example 9: Based on the above examples, as follows Figures 1 to 8 As shown, based on the coal seam conditions of the roadway roof described in this embodiment, to ensure the bearing capacity of the anchor bolts, the driving angle of the roadway sidewall anchor bolts 702 is as follows: for those near the roadway roof, the upward angle 12 with the roadway sidewall is 70°–80°, with 75° being optimal; for those near the floor, the downward angle 12 with the sidewall is 70°–80°, with 75° being optimal; the remaining roadway sidewall anchor bolts 702 are perpendicular to the roadway sidewall and arranged in a grid pattern. The spacing 703 of the roadway sidewall anchor bolts 702 is 900mm, and the row spacing 704 is 800mm. The specifications of the roadway sidewall anchor bolts 702 are φ18×1800mm. The ends of the roadway sidewall anchor bolts 702 are made of fiberglass to increase their strength. They are equipped with butterfly trays, spherical washers, and damping pads to enhance their load-bearing capacity. The butterfly trays are 120×120mm in size and 10mm thick. Each anchor bolt uses one roll of CK-2370 anchoring agent, with an anchoring force of 40kN and a torque of 40N·m. The roadway sidewall mesh 802 is a flame-retardant plastic mesh with steel wire, measuring 2600×10000mm in size and with a mesh size of 50×50mm. The roadway sidewall mesh 802 overlaps with a 200mm seam, and the overlaps are connected by double-stranded 14# iron wire with double-stranded double-row buckles.

[0040] Example 10: Based on the above examples, as follows... Figures 4 to 8 As shown, wooden strips 11 are placed between the front beam 104 of the support 1 and the roof of the tunnel to prevent the support 1 from becoming unstable during movement due to the increased space between the front beam 104 and the roof 601.

Claims

1. A method for handling roof compression in a fully mechanized mining face, comprising a support, a scraper conveyor, and a transport roadway. The support is positioned in front of the coal face in the mining area. The scraper conveyor is positioned below the support and hinged to a push-pull head of the support. The transport roadway is located on one side of the support. A roof compression cutting area is located above the support. A roadway is constructed on the side of the coal face, below the roof compression cutting area, and in front of the support. The length of the roadway is greater than or equal to that of the roof compression cutting area. Anchor bolt mesh supports are installed on the roadway roof and sidewalls. The anchor bolt mesh includes anchor bolts and mesh panels, which overlap and are connected by wire binding. The anchor bolts are driven into the overlapping areas of the mesh panels. The method comprises four working steps: coal face opening, roadway support, scraper conveyor and support base laying, and push-pull frame assembly. The specific steps are as follows: 1) Coal wall excavation: A roadway is gradually excavated on the side of the coal wall in the roof-cutting area by widening the sidewall. The roadway starts from the coal wall on the side of the transport roadway and the excavation length is greater than or equal to that of the roof-cutting area. 2) Roadway support: The roadway is supported on the top and side walls by anchor bolt mesh to prevent coal breakage and roof collapse, and to ensure the safety of the roadway. The anchor bolt mesh includes anchor bolts and mesh panels. The mesh panels overlap and are connected by wire. The anchor bolts include at least two evenly distributed roof anchor bolts and at least two evenly distributed side wall anchor bolts. The mesh panels include roof mesh panels and side wall mesh panels. The anchor bolts are driven into the overlapping parts of the mesh panels. 3) Scraper conveyor and support base plate: Drill shallow blast holes at the base plate in front of the support base and blast with explosives; after blasting, remove the broken rocks to lower the scraper conveyor and support base, and allow the support column to recover a small amount of travel. 4) Pushing and pulling the frame: Extend the push-pull head of the support and slowly push the scraper conveyor towards the roadway, causing the scraper conveyor to slowly land; after the scraper conveyor lands, apply a pressure column to fix it; then, retract the push-pull head of the support, moving the support towards the roadway; remove the pressure column, extend the push-pull head of the support again, and continue to slowly push the scraper conveyor towards the roadway, applying the pressure column again to fix it, retracting the push-pull head of the support, and moving the support; repeat the above steps several times until the scraper conveyor and the support move to the roadway, completing the process of handling the pressure column. The distance the scraper conveyor and the support move each time is controlled between 200 and 300 mm.

2. The method for handling the pressure on the longwall mining face according to claim 1, characterized in that, The driving angle of the roadway roof anchor bolts is as follows: the angle between the roadway roof anchor bolts near the sidewall and the roadway roof is 70° to 80°, and the remaining roadway roof anchor bolts are perpendicular to the roadway roof. The roadway roof anchor bolts are spaced 900mm apart, with a row spacing of 800mm, and have a specification of φ20×2200mm, arranged in a square grid pattern. The ends of the roadway roof anchor bolts are made of left-handed high-strength threaded steel without longitudinal ribs, and are equipped with butterfly trays, spherical washers, and damping pads. The butterfly trays are 120×120mm in size and 10mm thick, and are anchored using anchoring agent. The roadway roof mesh is a metal diamond mesh woven from iron wire, woven with #10 iron wire, with a specification of 1800×3000mm. The overlap between the roadway roof mesh panels is 200mm, and the overlap is connected by double-strand #14 iron wire double-strand double-row buckles, with a buckle spacing of 200mm.

3. The method for handling the pressure on the longwall mining face according to claim 1, characterized in that, The driving angle of the roadway sidewall anchors is as follows: for those near the roadway roof, the upward angle with the roadway sidewall is 70°–80°; for those near the floor, the downward angle with the sidewall is 70°–80°; the remaining roadway sidewall anchors are perpendicular to the roadway sidewall. The roadway sidewall anchors are φ18×1800mm in size, arranged in a grid pattern with a spacing of 900mm and a row spacing of 800mm. The ends of the roadway sidewall anchors are made of glass. The fiberglass anchor bolt ends are equipped with butterfly trays, spherical washers, and damping pads. The butterfly trays are 120×120mm in size and 10mm thick, and are anchored using anchoring agent. The tunnel sidewall mesh is a flame-retardant plastic mesh with steel wire, measuring 2600×10000mm in size and with a mesh size of 50×50mm. The tunnel sidewall mesh overlaps by 200mm, and the overlaps are connected by double-stranded 14# iron wire with double-stranded double-row buckles.

4. The method for handling the pressure on the longwall mining face according to claim 1, characterized in that, Wooden strips were placed between the front beam of the support and the roof of the tunnel to fill the gap.

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