A recovery and support method for fully mechanized mining working face

Abstract

The present invention discloses a method for recovering and supporting a fully mechanized mining face, comprising the following steps: Step 1: laying a double layer of wire mesh and hanging steel wire ropes; Step 2: installing square timbers; Step 3: installing anchor locks and securing the steel wire ropes with I-beams; Step 4: first fully extending the front beams of the hydraulic support, then retracting the front beams one by one starting from the tail frame, and installing a row of anchor cables along the mining face at the front end of the front beams, using T-shaped steel strips for support; Step 5: dismantling the hydraulic support; Step 6: interlocking and reinforcing the two rows of I-beams 1 laid in a tilted manner using anchor rods and iron backing plates; Step 7: after mining is stopped, the entire coal face of the mining face is covered with wire mesh and three rows of side anchor rods are installed. The present invention has been put into practical use in the 150314 mining face of a certain mine, ensuring safety and significantly improving recovery efficiency. The recovery rate has increased from two hydraulic supports per shift to four hydraulic supports per shift, saving labor and costs, and significantly improving the working environment of the mining face.

Description

Technical Field

[0001] The invention relates to a recovery and support method for a fully mechanized mining working face, belonging to the technical field of coal mine support. Background Art

[0002] A certain mine operates in close proximity to coal seams. Its roof is primarily composed of argillaceous siltstone, resulting in poor surrounding rock stability. Because the recovery line often takes a long time to prepare after mining, recovery cannot be carried out promptly. This prolonged downtime can affect the roof and easily lead to roof instability.

[0003] Using traditional support methods, such as Figure 1-Figure 5 As shown, when the working face is withdrawn, the empty roof section is supported by I-beam 1, and the support strength is insufficient. When the hydraulic support is unloaded, a roof collapse accident is likely to occur. At the same time, during the recovery of the working face, since the roof is in a completely unsupported state after the hydraulic support is recovered, a 20-inch air duct must be laid from bottom to top near the coal wall footing to ensure normal air supply to the recovery working face. The traditional recovery method uses the full collapse method for roof management. Each time a hydraulic support is recovered, the roof must be manually lowered, and the laid false roof is manually destroyed to prevent the roof from collapsing in time, resulting in a large area of ​​suspended roof. The sudden collapse of the roof causes a large-scale gas outburst in the recovered empty roof area, resulting in gas exceeding the limit.

[0004] Safety management risks are significant, particularly with the use of I-beams for advanced support of the exposed roof. This lack of support strength can easily lead to roof collapse accidents. Furthermore, with traditional support methods, the distance between the front exploration beam of the hydraulic support and the coal wall is only 0.8m, which does not meet safety requirements for recovery space. The hydraulic support also lacks sufficient space for directional adjustment, making collisions more likely. While the roof remains intact, manual forced roof release poses significant safety risks, as a roof collapse could easily injure people.

[0005] The labor intensity of employees is high. When using the traditional recycling method, a 20-inch air duct must be laid on the recycling work surface, and wooden top columns (single columns) and wood piles must be constructed on the gas pipe side to protect the air duct, resulting in a lot of physical labor for workers on the recycling work surface.

[0006] A large number of people are required, and at least 6 people must be present on the work surface to carry out recycling. At the same time, due to the use of a 20-inch air duct for air supply, the air volume is only 120-150m³ / min, resulting in a poor working environment. People work under high temperatures for a long time and are prone to fatigue. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a fully mechanized mining face recovery and support method to solve the technical problems existing in the above-mentioned prior art.

[0008] The technical solution adopted by the present invention is: a fully mechanized mining face recovery and support method, comprising the following steps:

[0009] Step 1: When the working face is mined to a position 11-13m away from the coal wall and the stop mining line, the first row of double-layer wire mesh is laid and the first steel wire rope is hung. The steel wire rope is arranged along the inclination direction of the mining face and parallel to the coal wall. The second steel wire rope is hung 280-320mm away from the first steel wire rope, and the third steel wire rope is hung 280-320mm away from the second steel wire rope. The double-layer wire mesh is laid from the bottom of the 1# frame at the front of the machine to the top of the tail frame at the rear of the machine.

[0010] Step 2: Install the square timber on the first row of wire mesh and tie the square timber to the wire mesh with wire;

[0011] Step 3: Install anchor locks at the upper and lower ends of the first three steel ropes, use I-beam 1 to stabilize the steel ropes, and then lay a row of wire mesh every two coal cuts, hanging a steel rope every 400-450mm;

[0012] Step 4: When the working face is 2-3m away from the stop mining line, do not pull the hydraulic support when cutting coal. First, fully extend the front beam of the hydraulic support, then retract the front beams one by one starting from the tail frame, and install a row of anchor cables along the mining face at the front end of the front beam. The anchor cable size is Φ21.6mm×6.3m, and the anchor cable spacing is 1.8-2m. Use T-shaped steel belts for support. After the steel belt support is completed, fully extend the front beam;

[0013] Step 5: Continue to cut coal forward to dismantle the hydraulic support. When dismantling the hydraulic support, install two I-beams 1 on each hydraulic support until all I-beams 1 are installed. Then, lay two rows of I-beams 1 along the inclination of the mining face below the installed I-beams 1. Use anchor cables to fix them every 1.8-2m. The size of the anchor cables is Φ21.6mm×6.3m. Interlock and reinforce all the I-beams 1 installed on the front beam.

[0014] Step 6: After the reinforcement is completed, anchor rods and iron back plates are used to interlock and reinforce the two rows of I-beams 1 laid in the middle of the two rows of I-beams 1 laid in the inclined direction;

[0015] Step 7: After stopping mining, all coal walls of the mining face are covered with wire mesh and three rows of anchor rods are installed. The anchor rods are arranged at the overlap of the wire mesh.

[0016] Preferably, in step seven, the anchor rods are arranged in three-point holes with a spacing of 800-900mm×1000-1100mm.

[0017] Preferably, before step one, when the coal wall of the working face is 20-22m away from the stop mining line, the mining face is adjusted to be parallel to the stop mining line, and the mining face height is greater than or equal to 2.5m to ensure that the mining face roof is intact and facilitate the support of the roof.

[0018] Preferably, the mining height is controlled to be above 3.0m when the working face stops cutting the last piece of coal, so that the mining face and transportation tunnel equipment can be recovered.

[0019] Preferably, double-strand 14# iron wire is used to bundle the steel rope and the wire mesh together under the double-layer wire mesh, and the bundling spacing is not more than 200mm; the specifications of each wire mesh are length × width 6.0-6.5m × 1.5-2.0m, the overlap length of the wire mesh is 100-120mm, and the overlap is tightened with double-strand 14# iron wire, and the spacing between the two tying wires is 200-230mm.

[0020] Preferably, the recovery order of the hydraulic supports is to recover each hydraulic support frame by frame from bottom to top.

[0021] Preferably, after the working face stops mining, wood piles must be added to the upper and lower tail tunnels for reinforced support. The lower end is reinforced with the original support form. After the support is recovered, a wood pile is erected in its place to support the top plate, replacing the original hinged top beam and single column for recovery. The upper end is supported by a group of 6-7m long I-beams and 2-3m anchor rods. The top of the I-beam is tightly connected with the top with a semi-circular log or a brake rod.

[0022] Preferably, when the brackets are started to be recovered upwards, single columns and 3-4m long π-shaped steel beams are used to cooperate with each other to support the top plate at the position of the recovered brackets, and the support is arranged in a "one beam and four columns" form along the direction. The spacing of the I-beam 1 is 750mm, and the spacing of the single columns is 800mm; when the recovery starts, the positions of two brackets are supported first, and then for each bracket recovered upwards, two π-shaped steel beams are recovered in sequence from bottom to top to support the position of the recovered bracket.

[0023] Preferably, when starting to recover the support upwards, a 2-3m long I-beam + anchor cable is used on the front exploration beam of the recovered support to support the roof. When the support is recovered and lowered, a single column is added to each I-beam. The distance between the single column and the coal seam column is 700-900mm. The two supports that are being recovered are replaced first.

[0024] Preferably, after each hydraulic support is recovered, a wood pile is set up at the place where the hydraulic support has been recovered. The wood pile is set up in a herringbone shape, and a wooden top column is set up every 700-900mm at the position near the old pond.

[0025] Beneficial effects of the present invention: Compared with the existing technology, the present invention has been actually applied in the 150314 mining face of a certain mine, and safety has been guaranteed. The efficiency of recovery has been greatly improved, from the original recovery of 2 hydraulic supports per shift to 4 hydraulic supports, which saves labor and costs, and the working environment of the working face has also been greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a traditional mining face support plan.

[0027] Figure 2 yes Figure 1 Middle AA section view.

[0028] Figure 3 yes Figure 1 Middle BB cross-section view.

[0029] Figure 4 It is a side section diagram of the local support of the coal wall in the traditional mining face.

[0030] Figure 5 This is a side cross-section diagram of the local support of another coal wall in the traditional mining face.

[0031] Figure 6 It is the mining face support plan in the present invention.

[0032] Figure 7 It is a partial cross-section diagram of the mining face support in the present invention.

[0033] Figure 8 This is another partial cross-section of the mining face support in the present invention.

[0034] Figure 9 This is another partial cross-section of the mining face support in the present invention.

[0035] Figure 10 This is another partial cross-section of the mining face support in the present invention.

[0036] The reference numerals in the drawings of the specification include: I-beam 1, bracket 2, single column 3, air duct 4, wire mesh 5, wood pile 6, anchor rod 7, steel wire rope 8, anchor cable 9, iron back plate 10, and steel belt 11. DETAILED DESCRIPTION

[0037] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0038] Example 1:

[0039] A fully mechanized mining face recovery support method, such as Figures 6-10 As shown, the following steps are included:

[0040] Step 1: When the working face is advanced to the position where the coal wall is 12m away from the stop mining line, the first row of double-layer wire mesh 5 is laid (the double-layer wire mesh 5 is laid from the lower side of the 1# frame to the upper side of the 106# frame at the tail of the machine), and the first steel wire rope 8 is hung. The steel wire rope 8 is arranged along the inclination direction of the mining face (and parallel to the coal wall of the mining face). The second steel wire rope 8 is hung at a distance of 300mm from the first steel wire rope 8, and the third steel wire rope 8 is hung at a distance of 300mm from the second steel wire rope 8.

[0041] Step 2: Install square timber (dividing a round timber into four) on the first row of wire mesh 5 and tie the square timber to the wire mesh 5 using tying wire.

[0042] Step 3: Anchor rope locks are placed at the upper and lower ends of the first three steel ropes 8, and the steel ropes 8 are stabilized with I-beams 1. Then, a row of wire mesh 5 is laid forward every two coal cuts, and a steel rope 8 is hung every 400mm.

[0043] Step 4: When the working face is 2m away from the stop mining line, cut a piece of coal first to extend the front exploration beam. The frame cannot be pulled and moved. After the coal cutting is completed, retract the front beam from the tail frame in sequence, and set a row of anchor cables 9 (Φ21.6mm×6.3m) along the mining face at the front end of the front beam. The spacing between the anchor cables 9 is 1.8m. Use T-shaped steel belts 11 for support. After the steel belts 11 support, extend the front exploration beam.

[0044] Step 5: Continue to cut coal forward to dismantle the hydraulic support 2. When dismantling the hydraulic support 2, install two 4m long I-beams 1 on each hydraulic support 2 until all the I-beams 1 are installed. Then, lay two rows of I-beams 1 along the inclination of the mining face below the installed I-beams 1. The length of the I-beam 1 is 3.6m. Anchor cables 9 are used to fix them every 1.8m. The size of the anchor cables 9 is Φ21.6mm×6.3m. All the I-beams 1 installed on the front beam are interlocked and reinforced.

[0045] Step 6: After the reinforcement is completed, a row of φ22mm×2.5m anchor rods 7 are driven in the middle of the two rows of I-beams 1 laid at a distance of 300mm from the coal wall, and a 5mm thick 800 iron back plate 10 is used for support. The spacing between the anchor rods 7 is 1.5m, and the two rows of I-beams 1 laid at a tilt are interlocked and reinforced.

[0046] Step 7: After stopping mining, all coal walls of the mining face are hung with wire mesh 5 and three rows of side anchor rods 7 are installed (arranged according to three eyelets, with a row spacing of 800mm×1000mm, and additional coal side columns are used for support in unstable areas of the coal wall surrounding rock). The anchor rods 7 are arranged at the overlap of the wire mesh 5.

[0047] In this embodiment, when the coal wall of the working face is 20m away from the stop mining line, the mining face must be adjusted to be parallel to the stop mining line, and the mining face height must be guaranteed to be 2.5m to ensure that the mining face roof is intact and facilitate roof support.

[0048] In this embodiment, when the working face stops mining and the last coal is cut, the mining height must be controlled above 3.0m to facilitate the recovery of the mining face and transport tunnel equipment.

[0049] In this embodiment, the double-layer wire mesh 5 and the steel rope 8 are laid along the inclined direction of the mining face (parallel to the coal wall of the mining face), and the steel rope 8 and the wire mesh 5 are bundled together with double strands of 14# wire under the double-layer wire mesh 5, and the bundling spacing is not greater than 200mm; the specifications of each wire mesh 5 are length × width = 6.0m × 1.76m, the overlap length of the wire mesh 5 is 100mm, and the overlap is tightened with double strands of 14# wire, and the spacing between the two tying wires is 200mm.

[0050] The recovery order of the hydraulic support 2 is to recover each support frame from bottom to top.

[0051] Other requirements for recycling hydraulic support 2:

[0052] 1. After the working face stops mining, wood piles 6 must be added to the upper and lower tail tunnels for reinforced support. The lower end is reinforced with the original support form. After the support 2 is recovered, a wood pile 6 is erected in its place to support the top plate, replacing the original hinged top beam and single column 3 for recovery; the upper end directly replaces the original support form of the hinged top beam and single column 3, and uses a group of 6m long I-beams and 2.5m anchor rods 7 (the spacing between the anchor rods 7 is 800mm×800mm, and each anchor rod 7 uses 1 section of MSK2380 resin anchor agent) to support the upper end. The top of the I-beam 1 is tightly connected with the top with a semi-circular log or a brake rod.

[0053] 2. When starting to recover the bracket 2 upwards, use a single column 3 and a 3.3m long π-shaped steel beam to cooperate with each other to support the top plate at the position of the recovered bracket 2, and set up a "one beam and four columns" support form along the direction. The spacing of the I-beam 1 is 750mm, and the spacing of the single column 3 is 800mm; when starting to recover, first support the positions of two brackets 2, and then every time a bracket 2 is recovered upwards, two π-shaped steel beams are recovered from bottom to top in turn to support the position of the recovered bracket 2.

[0054] 3. When starting to recover the support 2 upwards, use a 2.8m long I-beam 1 + anchor cable 9 on the front exploration beam of the recovered support 2 to support the roof. When the support 2 is recovered and lowered, a single column 3 is added to each I-beam 1. The distance between the single column 3 and the coal seam column is 800mm. Replace the two supports 2 that are being recovered first. If the added single column 3 affects the lowering and adjustment of the support 2, the column must be changed in advance.

[0055] 4. After each hydraulic support 2 is recovered, a wood pile 6 is set up at the location of each recovered support 2. The wood pile 6 is set up in a herringbone shape, and a wooden top column is set up every 800mm at the position close to the old pond.

[0056] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A fully mechanized mining face recovery and support method, characterized by: The following steps are involved: Step 1: When the working face is mined to a position 11-13m away from the coal wall and the stop mining line, the first row of double-layer wire mesh is laid and the first steel wire rope is hung. The steel wire rope is arranged along the inclination direction of the mining face and parallel to the coal wall. The second steel wire rope is hung 280-320mm away from the first steel wire rope, and the third steel wire rope is hung 280-320mm away from the second steel wire rope. The double-layer wire mesh is laid from the bottom of the 1# frame at the front of the machine to the top of the tail frame at the rear of the machine. Step 2: Install the square timber on the first row of double-layer wire mesh and tie the square timber to the double-layer wire mesh with wire; Step 3: Anchor cables are placed at the upper and lower ends of the first three steel ropes, and the steel ropes are stabilized with I-beams. Then, a row of double-layer wire mesh is laid forward every two coal cuts, with one steel rope hung every 400-450mm. Step 4: When the working face is 2-3m away from the stop mining line, do not pull the hydraulic support when cutting coal. First, fully extend the front beam of the hydraulic support, then retract the front beams one by one starting from the tail frame, and install a row of anchor cables along the mining face at the front end of the front beam. The anchor cable size is Φ21.6mm×6.3m, and the anchor cable spacing is 1.8-2m. Use T-shaped steel belts for support. After the steel belt support is completed, fully extend the front beam; Step 5: Continue to cut coal forward to dismantle the hydraulic support. When dismantling the hydraulic support, install two I-beams on each hydraulic support until all I-beams are installed. Then, lay two rows of I-beams along the inclination of the mining face below the installed I-beams. Use anchor cables to fix them every 1.8-2m. The size of the anchor cables is Φ21.6mm×6.3m. Interlock and reinforce all the I-beams installed on the front beam. Step 6: After the reinforcement is completed, use anchor rods and iron back plates to interlock and reinforce the two rows of I-beams laid in the middle of the two rows of I-beams laid in the inclined direction; Step 7: After stopping mining, all coal walls of the mining face are covered with double-layer wire mesh and three rows of anchor rods are installed. The anchor rods are arranged at the overlap of the double-layer wire mesh.

2. A fully mechanized mining face recovery and support method according to claim 1, characterized in that: In step seven, the anchor rods are arranged in three-point holes with a spacing of 800-900mm×1000-1100mm.

3. A fully mechanized mining face recovery and support method according to claim 1, characterized in that: Before step one, when the coal wall of the working face is 20-22m away from the stop mining line, the mining face is adjusted to be parallel to the stop mining line, and the mining face height is greater than or equal to 2.5m to ensure that the mining face roof is intact and convenient for supporting the roof.

4. A fully mechanized mining face recovery and support method according to claim 1, characterized in that: When the working face stops mining and cuts the last piece of coal, the mining height is controlled at above 3.0m to facilitate the recovery of the mining face and transport tunnel equipment.

5. The method for recovering and supporting a fully mechanized mining face according to claim 1, characterized in that: Double-strand 14# iron wire is used to bundle the steel wire rope and the double-layer wire mesh together under the double-layer wire mesh, and the bundling spacing is no more than 200mm; the specifications of each double-layer wire mesh are length × width 6.0-6.5m × 1.5-2.0m, and the overlap length of the double-layer wire mesh is 100-120mm. The overlap is tightened with double-strand 14# iron wire, and the spacing between the two tying wires is 200-230mm.

6. A fully mechanized mining face recovery and support method according to claim 1, characterized in that: The recovery order of hydraulic supports is to recover each support frame from bottom to top.

7. A fully mechanized mining face recovery and support method according to claim 6, characterized in that: After the working face stops mining, wood piles must be added to the upper and lower tail tunnels for reinforced support. The lower end must be reinforced with the original support form. After the support is recovered, a wood pile is erected in its place to support the top plate, replacing the original hinged top beam and single column for recovery. The upper end is supported by a group of 6-7m long I-beams and 2-3m anchor rods. The top of the I-beam is tightly connected with the top with a semi-circular log or brake rod.

8. A fully mechanized mining face recovery and support method according to claim 6, characterized in that: When starting to reclaim the supports upwards, single columns and 3-4m long π-shaped steel beams are used to cooperate with each other to support the top plate at the position of the recovered supports. The support is set up in a "one beam and four columns" form along the strike direction. The spacing of the I-beams is 750mm, and the spacing of the single columns is 800mm. When starting to reclaim, first support the positions of two supports, and then for each support reclaimed upwards, two π-shaped steel beams are recovered from bottom to top in turn to support the position of the recovered supports.

9. A fully mechanized mining face recovery and support method according to claim 6, characterized in that: When starting to recover the support upwards, use 2-3m long I-beams + anchor cables on the front exploration beam of the recovered support to support the roof. When the support is recovered and lowered, one single column is added to each I-beam. The distance between the single column and the coal seam column is 700-900mm. Replace the two supports that are being recovered first.

10. A fully mechanized mining face recovery and support method according to claim 6, characterized in that: After each hydraulic support is recovered, a wood pile is set up at the location of each recovered hydraulic support. The wood pile is set up in a herringbone shape. At the side of the old pond, a wooden top column is set up every 700-900mm.

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