Large-dip-angle face removing channel trend expanding and brushing process

Abstract

The invention relates to the technical field of coal mining safety, in particular to a large-dip-angle face removing channel trend expanding and brushing process, a coal mining machine is adopted for carrying out trend stripping construction on a face removing channel, stripping construction is carried out in a circulation mode, and the advancing distance of each stripping circulation is 0.5-1.2 m; in at least one initial wall stripping cycle, the coal mining machine performs wall stripping on the working face and supports in a matched manner; in the stripping and supporting process, a conveyor and a coal mining machine are pushed by a support pushing device to complete coal cutting in a segmented mode, and supporting operation is carried out synchronously. After at least one stripping cycle is completed, the conveyor is integrally pushed, and the conveyor is pushed in a segmented pushing mode along the inclined direction of the working face. According to the technology, the mode that segmented circulation stripping and conveyor pushing are combined, and segmented coal cutting of a coal mining machine and roof supporting are conducted synchronously is adopted, mutual interference caused by multi-point simultaneous construction is avoided, the long-term stability of a roadway structure is guaranteed, and efficient expanding and brushing of a large-dip-angle face removing channel are achieved.

Description

Technical Field

[0001] This invention relates to the field of coal mine safety technology, specifically to a process for widening and expanding the orientation of a steep-angle face removal channel. Background Technology

[0002] In recent years, with the continuous increase in coal mining intensity, near-horizontal and gently dipping coal seam resources in underground coal mines have gradually been depleted, with the remaining exploitable resources mostly being steeply dipping coal seams. Under steeply dipping conditions (dipping angle greater than 35°), the construction of exit tunnels has become a major technical challenge for coal mining enterprises. Traditional fully mechanized tunneling equipment is inefficient or even unusable under steeply dipping conditions, and the one-time construction of large-section exit tunnels poses significant safety risks. Therefore, existing technologies typically employ a phased blasting construction process. In this process, after the longwall face is pushed out, blasting is used to widen and enlarge the exit tunnel to form the exit tunnel required for equipment removal. However, as coal resources concentrate in steeply dipping coal seams, the slope of exit tunnel construction is mostly above 25°, severely restricting the efficiency and safety of traditional blasting and dipping methods in practical applications.

[0003] Specifically, the existing blasting and diversion process for steep-angle channel blasting has the following main problems: Low construction efficiency: The blasting process typically involves arranging blast holes along the dip, with each blasting operation forming a group, each group consisting of a row of five-hole steel strips. Frequent personnel evacuation and repositioning are required during group construction, leading to mutual interference between construction points and overall low construction efficiency; Insufficient safety: Multiple blasting points during construction pose risks of excessive gas and dust levels; long blasting time for personnel within the tunnel, and difficulty in preventing rock roll under steep-angle conditions; safety risks associated with handling residual or misfired blasts; and susceptibility to damage during blasting operations. Intelligent systems for electromechanical equipment and supports in the longwall mining face; poor roof stability: multi-point blasting disturbs the stress distribution around the roadway, leading to a redistribution of roof stress after the face removal channel is widened, resulting in roof subsidence and increased delamination; difficult management of flying rock: at an angle of about 40°, the rolling speed of coal or gangue can reach 12~15m / s, and there is a serious risk of injury to personnel if there are personnel below the widening channel at multiple locations; high pressure on on-site safety management: the blasting and widening construction cycle is long, the workload of safety management is large, and it is easy to cause safety fatigue and reduced safety awareness among construction personnel. Summary of the Invention

[0004] To address the significant shortcomings of existing steep-angle face removal tunnel blasting and shoveling techniques in terms of safety, efficiency, roof stability, and rockfall prevention, this invention provides a steep-angle face removal tunnel shoveling and shoveling process to achieve safe and efficient construction, providing technical support for face removal tunnel construction in underground coal mines. The specific technical solution is as follows: A process for widening and expanding a steep-angle face removal channel includes: the construction slope of the steep-angle face removal channel is greater than 25°; during the face removal stage of the steep-angle working face, a coal mining machine is used to perform face stripping construction on the face removal channel; the face stripping construction is carried out in a cyclic manner, with each stripping cycle advancing a distance of 0.5~1.2m; in at least one initial face stripping cycle, the coal mining machine strips the working face and provides support; in one or more subsequent face stripping cycles, the connection between the conveyor and the support is maintained in a certain area of ​​the working face, and the coal mining machine cuts and supports the middle and / or lower areas of the working face to limit the downward trend of the conveyor on the inclined working face; after completing the predetermined face stripping cycle, the conveyor is fixed with anti-slip treatment, and at least part of the connection between the conveyor and the support is released, and then the coal mining machine cuts and supports the working face again. During the stripping and support process, the conveyor is moved using the support moving device, and the coal mining machine completes coal cutting in sections while simultaneously performing support operations. After completing at least one stripping cycle, the conveyor is moved as a whole, using a sectioned moving method along the working face dip. After the conveyor is moved, it is secured with anti-slip measures, and while gradually disconnecting the conveyor from the support, supplementary support is provided to the working face in conjunction with the coal mining machine's coal cutting operations. At least four coal cutting cycles are completed according to the sequence of coal cutting-moving-support operations.

[0005] Furthermore, the operating direction, cutting direction, and cutting sequence of the coal mining machine are alternated in different coal cutting cycles to reduce the stress concentration and slippage risk of the conveyor on the inclined working face. The inclined operation length of a single coal cutting operation by the coal mining machine is 30~60m.

[0006] Furthermore, before the transport machine moves, the forward movement of the working face support is stopped, and individual support devices are installed on both sides of the transport machine's slipway area to provide temporary stabilization support for the slipway position during the initial stage of the transport machine's movement.

[0007] Furthermore, during the movement of the transport aircraft, the connection between the transport aircraft and the support is disconnected in sections along the direction of the working face. For every 8 to 15 support connection points disconnected, a single support device is installed for temporary support.

[0008] Furthermore, the segmented movement of the transport aircraft is accomplished through the cooperation of the support moving device and the individual support device. During the moving process, safety control measures such as anti-tipping, anti-slip, and long-distance liquid supply are taken for the individual support device.

[0009] Furthermore, after the transport vehicle has been moved, individual support devices and / or anchoring structures are installed at intervals along the length of the working face to prevent the transport vehicle from slipping and to limit its displacement in the tilt direction.

[0010] Furthermore, the initial support force of the single support device is 90~120kN, and it forms a force-bearing connection with the transport machine and the support through the column claw and column base respectively.

[0011] Furthermore, the anchoring structure is set in the conveyor head area and / or the middle area of ​​the working face, and is distributed at predetermined intervals along the length of the working face.

[0012] Furthermore, the anchoring structure includes an anchor rod, the anchor rod having a length of 1800~2600mm and a diameter of 18~25mm.

[0013] Furthermore, the anchor bolt is a threaded steel anchor bolt of equal strength, and is anchored to the surrounding rock through a resin-based anchoring material.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention provides a method for widening and expanding a steep-angle face removal channel by employing a combination of segmented cyclic stripping and conveyor pushing. This reduces the need for frequent personnel deployment and avoids mutual interference from simultaneous multi-point construction, achieving efficient widening and expansion of the steep-angle face removal channel. During construction, the coal cutting machine cuts coal in segments simultaneously with roof support, maintaining a stable stress distribution around the face removal channel, reducing roof subsidence and delamination, and ensuring the long-term stability of the roadway structure.

[0015] 2. The steep-angle coal cutting and channel widening process provided by this invention reduces the risks of conveyor slippage, roof collapse, and rockfall injuries by maintaining partial connection of the conveyor, segmented cutting, and individual support pillars and ground anchors for anti-slip support. It also reduces the number of times personnel need to enter high-risk areas, thereby improving construction safety. Furthermore, the combination of segmented coal cutting and individual support controls coal falling within a manageable area, reducing the speed and range of rockfall and effectively alleviating the pressure of rockfall prevention management at the construction site. In addition, this invention employs coordinated operation of the all-coal cutting machine and the conveyor pushing, resulting in a short safety management cycle, simple construction control, reduced safety fatigue, and improved on-site management efficiency and vigilance.

[0016] 3. The steep-angle face-removal channel directional widening and scouring process provided by this invention is applicable to steep-angle coal seams with an inclination angle of 25° or even greater than 40°. It overcomes the limitations of traditional blasting excavation technology in terms of low efficiency and high risk under high inclination conditions, and is suitable for the construction needs of steep-angle face-removal channels in modern underground coal mines. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with preferred embodiments. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0018] Example 1: Large-angle surface cleaning channel directional expansion process 1. Construction Method: The face stripping process for the working face is conducted using a coal mining machine, with each stripping cycle progressing 0.8m. The first stripping cycle uses the coal mining machine to complete the initial stripping. To prevent the conveyor from slipping, the connection between the upper support of the working face and the conveyor remains intact during the second and third stripping cycles. Simultaneously, the coal mining machine cuts the lower and middle sections of the working face for support. After the third stripping cycle, the conveyor is secured with ground anchors. The connection between the upper conveyor and the support is then removed, and the coal mining machine continues to cut the working face for support. The working face uses a support-pushing beam to move the conveyor. The coal mining machine cuts coal in sections sequentially, simultaneously completing the support. The inclined length of each cut is 40m.

[0019] 2. Conveyor Moving: After the forward support stops moving at the working face, the first stripping cycle of the coal mining machine is completed, and the conveyor is moved into position. The moving is carried out from bottom to top: First, the individual supports on both sides directly in front of the conveyor head are removed, with two supports on each side, and the supports are supported tightly against the conveyor head frame; the connectors are removed sequentially upwards, and individual supports are installed at the corresponding positions after every 10 connectors are removed. Subsequently, the connectors between the moving beams and the conveyor are removed, and the conveyor is manually moved in conjunction with the addition of moving beams and individual supports every ten sets.

[0020] During the chute relocation process, each individual support pillar must be equipped with an anti-tipping rope, operated by two people and monitored by one. The pillar anchors must be complete, and wooden wedges or other small pieces of wood should be placed at the base of the pillar to prevent slippage. After the individual support pillar applies force against the chute, the high-pressure liquid valve should be closed, the injection gun trigger secured, and the valve assembly used for long-distance liquid supply. Personnel should avoid areas where the individual pillar might spring back and slip, potentially causing injury, and a designated person should be responsible for monitoring.

[0021] 3. Conveyor Anti-slip: After the conveyor is moved, remove the temporary supports on both sides of the chute. Install individual supports every 10 conveyors, with the support claws resting on the gear rail and the support base on the top beam of the support frame, and equipped with anti-tipping ropes. Install two individual supports at positions 10-40 conveyors, spaced approximately 1 meter apart; install one individual support at positions above 50 conveyors to prevent the conveyor chute from sliding down. The initial support force of each individual support is 90kN. After the third stripping cycle, install two sets of ground anchors on each side of the chute, and two sets of ground anchors for every 10 conveyors on the working face for anti-slip fixation. Then, remove the connecting joints from bottom to top, and the coal mining machine moves upwards to cut coal and install additional supports. The ground anchors are MSGLD-400 φ22×2200 high-strength threaded steel resin anchor bolts.

[0022] 4. Coal Cutting Cycle: The first coal cutting cycle begins with the coal mining machine descending to cut the cutting edge, performing initial stripping of the working face. Simultaneously, the conveyor belt moves forward 0.8m. The coal mining machine then ascends to cut the triangular coal face, before descending again to cut coal in sections, each section not exceeding 40m in length. Roof support is completed simultaneously. The machine descends to the lower conveyor head position to complete this cycle and is then lifted to the 50th frame position on the working face. The second coal cutting cycle then begins. The conveyor belt moves forward 0.8m, the coal mining machine descends to cut the cutting edge, then ascends to cut the triangular coal face. The machine then ascends again to cut coal in sections, simultaneously completing the roof support. In the first cutting cycle, the coal mining machine descends again to cut the cutting edge, while simultaneously pushing the conveyor 0.8m to complete the upward cutting of the triangular coal face. Then, the coal mining machine descends again to cut coal in sections and provides roof support, descending to the chute position to complete the cycle and being pulled back up. In the second cutting cycle, the working face conveyor pushes the chute 0.2m to complete the cycle, the coal mining machine descends to cut the cutting edge, ascends again to push the chute and complete the upward cutting of the triangular coal face. Then, the coal mining machine ascends again to cut coal in sections and provides side support, finally being pulled back up to the top end position to complete the entire cutting cycle.

[0023] This technology was implemented in the 21105 face removal passage of Huafeng Coal Mine. The construction slope of the face removal passage is 33~38°, and the daily construction progress can reach 80 meters, increasing the single-shift progress by 167%.

[0024] Example 2: Large-angle surface cleaning channel directional expansion process 1. Construction Method: The face stripping process for the working face is conducted using a coal mining machine, with each stripping cycle progressing 1 meter. The first stripping cycle involves the coal mining machine to complete the initial stripping. To prevent the conveyor from slipping, the connection between the upper support of the working face and the conveyor remains intact during the second and third stripping cycles. Simultaneously, the coal mining machine cuts the lower and middle sections of the working face for support. After the third stripping cycle, the conveyor is secured with ground anchors. The connection between the upper conveyor and the support is then removed, and the coal mining machine continues to cut the working face for support. The working face uses a support-pushing beam to move the conveyor. The coal mining machine cuts coal in sections sequentially, simultaneously completing the support. The inclined length of each coal cutting operation is 30 meters.

[0025] 2. Conveyor Moving: After the forward support stops moving at the working face, the first stripping cycle of the coal mining machine is completed, and the conveyor is moved into position. The moving is carried out from bottom to top: First, the individual supports on both sides directly in front of the conveyor head are removed, with two supports on each side, and the supports are supported tightly against the conveyor head frame; the connectors are removed sequentially upwards, and individual supports are installed at the corresponding positions after every 15 connectors are removed. Subsequently, the connectors between the moving beam and the conveyor are removed, and the conveyor is manually moved in conjunction with the addition of moving beams every ten sets of individual supports.

[0026] During the chute relocation process, each individual support pillar must be equipped with an anti-tipping rope, operated by two people and monitored by one. The pillar anchors must be complete, and wooden wedges or other small pieces of wood should be placed at the base of the pillar to prevent slippage. After the individual support pillar applies force against the chute, the high-pressure liquid valve should be closed, the injection gun trigger secured, and the valve assembly used for long-distance liquid supply. Personnel should avoid areas where the individual pillar might spring back and slip, potentially causing injury, and a designated person should be responsible for monitoring.

[0027] 3. Conveyor Anti-slip: After the conveyor is moved, remove the temporary supports on both sides of the chute. Install individual supports every 10 conveyors, with the support claws resting on the gear rail and the support base on the top beam of the support frame, and equipped with anti-tipping ropes. Install two individual supports at positions 10-40 conveyors, spaced approximately 1 meter apart; install one individual support at positions above 50 conveyors to prevent the conveyor chute from sliding down. The initial support force of each individual support is 100kN. After the third stripping cycle, install two sets of ground anchors on each side of the chute, and two sets of ground anchors every 10 conveyors on the working face for anti-slip fixation. Then, remove the connecting joints from bottom to top, and the coal mining machine moves upwards to cut coal and install additional supports. The ground anchors are MSGLD-400 φ25×2500 high-strength threaded steel resin anchor bolts.

[0028] 4. Coal Cutting Cycle: The first coal cutting cycle begins with the coal mining machine descending to cut the cutting edge, performing initial stripping of the working face. Simultaneously, the conveyor belt moves forward 1 meter. The coal mining machine then ascends to cut the triangular coal face, followed by descending again to cut coal in sections, each section being 30 meters long. Roof support is completed simultaneously. The machine descends to the lower conveyor head position to complete this cycle and is then lifted to the 50th support position on the working face. The second coal cutting cycle then begins, with the conveyor belt moving forward 1 meter. After the coal mining machine descends to cut the cutting edge, it ascends to cut the triangular coal face. The machine then ascends again to cut coal in sections, simultaneously completing roof support. In the first cutting cycle, the coal mining machine descends again to cut the cutting edge, while simultaneously pushing the conveyor for 1 meter. After cutting the triangular coal face upwards, the coal mining machine descends again to cut coal in sections and provides roof support. It descends again to the chute head position to complete the cycle and is then lifted. In the second cutting cycle, the working face conveyor moves forward for 0.2 meters, the coal mining machine descends to cut the cutting edge, then ascends again to push the chute and completes the cutting of the triangular coal face upwards. Subsequently, the coal mining machine ascends again to cut coal in sections and provides side support. The coal mining machine is then lifted to the upper end position to complete the entire cutting cycle.

[0029] This technology was implemented in the 21105 face removal passage of Huafeng Coal Mine. The construction slope of the face removal passage is 33~38°, and the daily construction progress can reach 30 meters, increasing the single-shift progress by 100%.

[0030] As can be seen from the above embodiments, the coal cutting and tracing process of the steep-angle coal face removal channel provided in this application can realize the integrated continuous operation of cutting, coal dropping, coal loading and transportation by utilizing the production system of the longwall mining face. It eliminates the need for multiple blasting, manual gangue removal and ventilation and dust removal in the traditional blasting process, significantly reducing the auxiliary operation time, and is especially suitable for engineering projects with tight schedules.

[0031] Because blasting is eliminated, safety hazards such as gas explosions, blasting injuries, and falling rocks are removed, reducing the accident rate by approximately 60%. During operation, the coal mining machine uses drum cutting to precisely cut the coal face and rock wall, minimizing disturbance to the surrounding rock. Combined with timely support (such as anchor bolts and cables), this effectively reduces the risks of roof collapse and spalling. The absence of blasting significantly improves the working environment, drastically reducing dust and harmful gas emissions (such as carbon monoxide). Dust concentration is reduced by approximately 70%, and with the coal mining machine's spray dust suppression equipment, low-dust operation is achieved, protecting workers' occupational health. Furthermore, the absence of blasting noise (≤90 decibels) avoids the health impacts of high noise levels (up to 110 decibels) encountered in blasting, meeting green mine construction standards.

[0032] Meanwhile, the coal mining machine can precisely control the cross-sectional shape of the roadway (such as rectangular or trapezoidal) according to design parameters, with a cross-sectional error controlled within 50mm. In contrast, blasting is easily affected by blasting vibrations, and the error can reach 100-200mm. When cutting the roof and floor, the coal mining machine can accurately level the surface, avoiding the unevenness of the roof and floor caused by blasting. This reduces the occurrence of equipment jamming during retraction and uneven sliding plate laying, while also reducing damage to the surrounding rock, improving the roadway support effect, and reducing the amount of maintenance work such as subsequent anchor bolt installation by 30%-50%.

[0033] Furthermore, this technology is highly adaptable to complex geological conditions. In environments such as soft rock, fractured zones, and steeply dipped coal seams, the coal mining machine can maintain stable operation by adjusting cutting parameters (such as drum speed and advance speed). In contrast, blasting can easily exacerbate surrounding rock damage due to blasting vibrations. For face-clearing passages requiring precise widening (such as chambers and connecting roadways), the coal mining machine can more easily control the widening range, avoiding damage to surrounding facilities (such as pipelines, cables, and intelligent support systems). This technology is compatible with mature longwall mining production systems, reduces manual operation, lowers labor intensity, and is suitable for the requirements of intelligent mine construction.

[0034] Although the present invention has been described in detail by way of preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. A process for expanding and widening the scouring channel at a large angle, characterized in that, include: During the face removal stage of a steeply inclined working face, a coal mining machine is used to perform face stripping construction on the face removal passage. The face stripping construction is carried out in a cyclic manner, with each stripping cycle advancing a distance of 0.5~1.2m. In at least one initial face stripping cycle, the coal mining machine strips the working face and provides support. In one or more subsequent face stripping cycles, the connection between the conveyor and the support is maintained in a certain area of ​​the working face, and the coal mining machine cuts and supports the middle and / or lower areas of the working face. After completing the predetermined face stripping cycle, the conveyor is fixed with anti-slip treatment, and at least part of the connection between the conveyor and the support is released. Then, the coal mining machine cuts and supports the working face again. During the stripping and support process, the conveyor is moved using the support pushing device, and the coal mining machine completes coal cutting in a segmented manner while simultaneously carrying out support operations. After completing at least one stripping cycle, the conveyor is moved as a whole, using a segmented moving method along the working face inclination. After the conveyor is moved, it is secured with anti-slip measures, and while gradually disconnecting the conveyor from the support, the coal cutting operation of the coal mining machine is coordinated to provide supplementary support to the working face. At least four coal cutting cycles are completed according to the sequence of coal cutting-moving-supporting operations. The construction slope of the steep-angle stripping channel is greater than 25°.

2. The large-angle channel tracing and expansion process according to claim 1, characterized in that, In different coal cutting cycles, the operating direction, cutting direction, and coal cutting sequence of the coal mining machine are set alternately, and the inclined operation length of a single coal cutting operation by the coal mining machine is 30~60m.

3. The large-angle channel tracing and expansion process according to claim 1 or 2, characterized in that, Before the transport machine moves, stop the forward movement of the working face support and install individual support devices on both sides of the transport machine's head area.

4. The large-angle channel tracing and expansion process according to claim 3, characterized in that, During the movement of the transport aircraft, the connection between the transport aircraft and the support is disconnected in sections along the direction of the working face. After disconnecting 8 to 15 support connection points, a single support device is set up for temporary support.

5. The large-angle channel tracing and expansion process according to claim 4, characterized in that, The segmented movement of the transport aircraft is accomplished through the cooperation of the support moving device and the single support device. During the moving process, safety control measures such as anti-tipping, anti-slip, and long-distance liquid supply are taken for the single support device.

6. The large-angle surface-expanding scouring process according to claim 1, characterized in that, After the transport vehicle has been moved, individual support devices and / or anchoring structures are installed at intervals along the length of the working face to prevent the transport vehicle from slipping and to secure it.

7. The large-angle channel tracing and expansion process according to claim 6, characterized in that, The initial support force of the single support device is 90~120kN, and it is connected to the transport machine and the support frame through the column claw and column base respectively.

8. The large-angle channel tracing and expansion process according to claim 6 or 7, characterized in that, The anchoring structure is set in the conveyor head area and / or the middle area of ​​the working face, and is distributed at predetermined intervals along the length of the working face.

9. The large-angle channel tracing and expansion process according to claim 8, characterized in that, The anchoring structure is an anchor rod, which has a length of 1800~2600mm and a diameter of 18~25mm.

10. The large-angle channel tracing and expansion process according to claim 9, characterized in that, The anchor bolt is a threaded steel anchor bolt of equal strength, and is anchored to the surrounding rock through a resin-based anchoring material.