Fully-mechanized caving stoping process and equipment suitable for steeply inclined thick coal seam

Abstract

The invention discloses a fully-mechanized caving stoping technology and equipment suitable for a steeply inclined thick coal seam, the fully-mechanized caving stoping technology adopts a two-mining and one-caving circulation mode for mining, the two-mining and one-caving circulation mode comprises two-time coal cutting and one-time coal caving, and the fully-mechanized caving stoping technology is specifically implemented according to the following steps that 1, the mining and caving ratio and the mining height are determined; step 2, first coal cutting operation; 3, frame moving and forward sliding pushing are conducted in sequence; step 4, pulling and sliding; 5, secondary coal cutting operation is carried out; 6, repeating the step 3; 7, top coal caving is conducted through a multi-round sequential coal caving process; 8, repeating the step 4; and 9, the steps 2-8 are cyclically carried out until the top coal is completely discharged, and the cycle is ended. The fully-mechanized caving recovery process and the fully-mechanized caving recovery equipment are high in recovery rate and low in gangue mixing rate; the support stability of equipment is enhanced, and the overall cost of a mine is reduced; the roof control capability is enhanced, wall caving and roof falling accidents are reduced, and the safety of field operation and the stability of a working face are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal mining, and relates to a fully-mechanized caving and mining process applicable to steeply inclined thick coal seams. The present invention also relates to mining equipment for executing the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams. Background Art

[0002] Steeply inclined thick coal seams usually refer to coal seams with an inclination greater than 45° and a thickness of more than 3.5 meters. Their mining is characterized by complex ground pressure distribution, poor coal rock stability, difficult mining site ventilation, and inconvenient coal transportation. Therefore, the mining of steeply inclined thick coal seams faces challenges such as difficult roof control, high requirements for equipment anti-slip, and complex coal placement technology.

[0003] When mining steeply inclined, thick coal seams, the distribution of ground pressure differs significantly from that of gently inclined seams. Due to the steep inclination of the coal seam, the direction of gravity acting on the roof rock changes. This results in roof pressure acting not only vertically downward but also exerting a significant component along the coal seam's inclination, increasing lateral pressure on supports and roadways. Furthermore, under the influence of gravity, the coal seam and its roof and floor rocks are prone to sliding and collapsing. This is particularly true during mining, where the coal and rock mass above the goaf loses support, making accidents such as roof falls and rock spalling more likely to occur.

[0004] Common mining methods include horizontal slicing, oblique slicing, top-coal caving, and pseudo-inclined flexible shield mining. Top-coal caving involves setting up a 2-3 meter high mining face along the bottom of a steeply inclined, thick coal seam. The mine pressure is then used to crush the top coal above the face, which is then discharged through the caving openings in the shields. This method significantly increases coal recovery and reduces mining costs.

[0005] In the existing technology, when the inclination angle is greater than 50°, the support frame movement in the traditional fully mechanized caving process is relatively continuous and synchronous, with small intervals, and does not take into account the poor support stability and high risk of slipping caused by the increase in the inclination angle; the coal caving port is opened for multiple times to release the top coal, resulting in uneven top coal release, a high rate of gangue mixing, and a low recovery rate; the coal cutting machine and the support frame movement lack coordination, affecting the advancement efficiency. Therefore, there is an urgent need for an optimized process for thick coal seams with large inclination angles to solve the above technical bottlenecks. Summary of the Invention

[0006] The first purpose of the present invention is to provide a fully mechanized caving and mining process suitable for steeply inclined thick coal seams, which solves the problems of uneven top coal discharge, high gangue mixing rate and low recovery rate in the prior art.

[0007] The second object of the present invention is to provide a fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams.

[0008] The first technical solution adopted by the present invention is a fully mechanized caving mining process applicable to steeply inclined thick coal seams, which adopts a "two-cutting and one-caving" cycle mode for mining. The "two-cutting and one-caving" cycle mode includes two coal cuttings and one coal caving, and is specifically implemented in the following steps: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, and determine the mining ratio and mining height; Step 2: First coal cutting operation; Step 3: Move the rack and push forward in sequence; Step 4: Pull back and slide; Step 5: Second coal cutting operation; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; the caving is completed in three rounds, with the caving volume of each round being 30% to 40%; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0009] The first technical solution of the present invention is also characterized in that: The mining-to-caving ratio is 1:2.6~1:3.3, and the mining height of the working face is 2.1m~2.3m; The process implementation requirements are: The shearer is hauled in a chainless manner with a hauling speed of ≥4.5m / min. The shearer includes a front drum and a rear drum. The support strength of the hydraulic support is ≥0.8MPa, and the initial support force is ≥24MPa; There are multiple hydraulic supports, and the top beams of the hydraulic supports have bidirectional side guard plates. The offset of adjacent hydraulic supports is ≤ 2 / 3 of the height of the side guard plates.

[0010] The specific steps of step 2 are: Step 2-1, parameter setting: each cut depth is 600mm, and the pulling speed is 1.5m / min~4.5m / min; Step 2-2: The coal cutting feed method is oblique cutting feed on the working face; Step 2-3: Cut coal in a downward one-way cutting manner; the front drum of the coal shearer cuts the top coal, and the rear drum cuts the bottom coal.

[0011] The specific implementation parameters of the rack moving in step 3 include the rack moving method, rack moving step distance, rack lowering amount and rack raising requirements; The frame moving method is grouped and intermittent, and each group includes two hydraulic supports. The supports in each group are moved in sequence according to the method of single supports. The frames are moved in an intermittent manner between groups. The distance between the moving supports and the rear drum in the forward direction of the coal mining machine is not more than 10 frames. The step distance of the rack moving should not be less than 600mm; the rack moving should be carried out in two steps, the first step is 300mm~500mm, and the second step is 100mm~300mm; The amount of lowering shall not exceed 200mm; The requirements for lifting the frame are: after lifting, the frame is straight, the skew error is no more than ±50mm, the center distance of the frame is 1500mm±100mm, the top beam of the frame must be parallel to the top plate, and its maximum elevation angle is less than 7°. The height difference between adjacent frames shall not exceed two-thirds of the maximum width of the side guard plate, and ensure that the initial support force is reached, and the distance between the beam ends shall not exceed 400mm.

[0012] The specific steps of pushing the front slide in step 3 are: push the front scraper conveyor in sequence according to the single frame. The length of the curved section during pushing should be no less than 12m, the horizontal curvature should be less than 2°, and the pushing step should be 600mm. When pushing the front slide, it should be pushed while the conveyor is running, and the machine head and tail can be stopped when pushing.

[0013] The specific steps of pulling and sliding in step 4 are: each group of 10 racks are pulled and slid in sequence along the rack moving direction at one time, with a step distance of 600mm.

[0014] The specific steps of the second coal cutting operation in step 5 are the same as the first coal cutting operation in step 2.

[0015] The specific steps of the multi-round sequential coal caving process are: the coal caving work starts when the cutting eye is opened, and the coal caving ports of each round of coal caving are opened in sequence from one end of the working face to the other end, and closed when the gangue is seen, until the top coal is caved.

[0016] The standard for top coal discharge is that only gangue is discharged from the coal outlet for three consecutive rounds without any coal flow.

[0017] The second technical solution adopted by the present invention is a fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams, which can execute the fully mechanized caving and mining process suitable for steeply inclined thick coal seams of the first technical solution, including a hydraulic support and a scraper conveyor placed vertically to each other, the base of the hydraulic support is fixedly connected to the trough side of the scraper conveyor, and two-way side guards are fixedly connected on both sides of the top beam of the hydraulic support; a coal mining machine is straddled above the scraper conveyor, and the coal mining machine includes a front roller and a rear roller; an anti-slip jack is provided between the base of the hydraulic support and the scraper conveyor; a hydraulic anchoring device is fixedly installed on the head or tail of the scraper conveyor.

[0018] The beneficial effects of the present invention are: The fully-mechanized caving and mining process for steeply inclined thick coal seams of the present invention is suitable for steeply inclined thick coal seams with an angle of 55 to 62 degrees. Through a "two-mining and one-caving" cycle, multiple rounds of coal caving and coordinated control of equipment, the caving characteristics of the coal seam are fully utilized, the roof stability pressure is reduced, and the safety of the working face is improved; the recovery rate is increased to more than 80%, and the gangue mixing rate is reduced to less than 10%; the support stability of the fully-mechanized caving and mining equipment for steeply inclined thick coal seams is enhanced, the slip accidents are reduced by 90%, and the overall cost of the mine is reduced; the roof control capability is enhanced, the spalling and roof-falling accidents are reduced, and the safety of on-site operations and the stability of the working face are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a process flow chart of the fully mechanized caving mining process applicable to steeply inclined thick coal seams; Figure 2 This is a schematic diagram of a single coal discharge form in the prior art; Figure 3 This is a schematic diagram of a multi-round coal caving process applicable to a steeply inclined thick coal seam according to the present invention; Figure 4 The diagram is a schematic diagram of the layout of the fully mechanized caving and mining equipment of the present invention applicable to steeply inclined thick coal seams.

[0020] In the figure, 1. hydraulic support, 2. coal mining machine, 3. scraper conveyor, 4. two-way side guard plate, 5. anti-slip jack, 6. hydraulic anchoring device. DETAILED DESCRIPTION

[0021] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] The present invention provides a fully mechanized caving mining process suitable for steeply inclined thick coal seams, which is suitable for steeply inclined thick coal seams with an inclination angle of 55°~62° and a thickness of ≥3.5m. Figure 1 As shown in the figure, the mining is carried out in the "two-cutting and one-caving" cycle mode, which includes two coal cutting and one coal caving, with a feed of 1.2m per cycle. The specific implementation is as follows: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, and determine the mining ratio and mining height; The mining ratio and mining height are set according to the coal seam thickness, inclination and equipment performance at the operation site; the mining ratio is 1:2.6~1:3.3; the working face mining height is 2.1m~2.3m; The process implementation requirements are: The shearer is hauled in a chainless manner with a hauling speed of ≥4.5m / min. The shearer includes a front drum and a rear drum. The support strength of the hydraulic support is ≥0.8MPa, and the initial support force is ≥24MPa; There are multiple hydraulic supports, and the top beam of the hydraulic support has two-way side guard plates. The offset of adjacent hydraulic supports is ≤ 2 / 3 of the side guard plate height; The support distance of the advanced tunnels at the upper and lower ends of the working face is 30m.

[0023] Step 2: First coal cutting operation; The shearer moves on the rack rails guided by the front chute and its rack rails. The unit cables and spray water pipes are arranged together in the cable trough of the front chute and are dragged and moved by the unit. The specific steps are: Step 2-1, parameter setting: each cut depth is 600mm, and the pulling speed is 1.5m / min~4.5m / min; According to the geological conditions such as the thickness, hardness, inclination and lithology of the coal seam, and in combination with the performance of the coal shearer and other equipment, the coal cutting parameters of the coal shearer should be reasonably set; Step 2-2: The coal cutting feed method is oblique cutting feed on the working face; Step 2-3, cutting coal in a downward one-way cutting manner; the front drum of the coal shearer cuts the top coal, and the rear drum cuts the bottom coal; When cutting coal, try to ensure that the top and bottom plates are flat and the coal walls are straight.

[0024] Step 3: Move the rack and push forward in sequence.

[0025] Following the coal mining machine, the hydraulic support is moved in time. The specific steps of the frame movement are: the support is lowered by the hydraulic system to separate from the roof, and then the push jack is used to move the support forward a step distance. After reaching the new position, the support is raised again to make the support closely contact with the roof and effectively support the roof. When lowering the rack, the amount of lowering shall not exceed 200mm, and the bracket shall be able to be moved; The frame moving method is grouped and interleaved. Each group includes two hydraulic supports. The supports in each group are moved in sequence according to the method of single supports. The frames between groups are moved in an interleaved manner. The distance between the moving supports and the drum in the forward direction of the coal mining machine is not more than 10 frames. This reduces the risk of back-slipping between supports and enhances the stability of the equipment and the roof support capacity. The rack is moved twice, the first time is 300mm~500mm, the second time is 100mm~300mm, and the two moving distances are not less than 600mm; the moving distance is the same as the cutting depth of each knife; When raising the frame, the top beam of the frame should be in even contact with the top plate. When the frame reaches the specified initial support force, the raising operation should be stopped. After raising the frame, the frame should be straight, with a skew error of no more than ±50mm, and the center distance of the frame should be 1500mm±100mm. The top beam of the frame should be parallel to the top plate, with a maximum elevation angle of less than 7°. The height difference between adjacent frames should not exceed two-thirds of the maximum width of the side guard plate, and ensure that the initial support force is reached. The distance between the beam ends should not exceed 400mm. When the roof is severely broken, the "follow the machine and move the frame" strategy is adopted: the support follows the rear drum of the coal mining machine, and the machine is stopped and the support is moved. The initial support force must reach the rated value of 24MPa; After the hydraulic support is moved, the front scraper conveyor is pushed toward the coal wall by the support's pushing jack, restoring it to a suitable working position and preparing for the next coal cutting.

[0026] The specific steps of push forward slide are: Push the front scraper conveyor in sequence according to the single frame. The length of the curved section during pushing should not be less than 12m, the horizontal curvature should be less than 2°, and the pushing step should be 600mm. When pushing the front slide, it should be pushed while the conveyor is running. The machine head and tail can be stopped. After pushing the front slide, the conveyor must be guaranteed to be flat, straight and stable, and the overlap between the machine head and the transfer machine should be appropriate.

[0027] Step 4: Pull back and slide; The specific steps of pulling and sliding are: each group of 10 frames are pulled and slid in sequence along the direction of frame movement at one time, with a step distance of 600mm; pulling and sliding back and pushing and sliding forward are operated by one person.

[0028] Step 5: Second coal cutting operation: The specific steps of the second coal cutting are the same as the first coal cutting, that is, repeat step 2.

[0029] Step 6. Repeat step 3.

[0030] Step 7: Use a multi-round sequential caving process to caving top coal; the caving is completed in three rounds, with the caving volume of each round being 30% to 40%; Multiple rounds of sequential coal discharge start from the time the cutting eye is opened. The coal discharge ports of each round are opened in sequence from one end of the working face to the other end, and closed when gangue is seen, until all the top coal is discharged. At the same time, the amount of coal discharged is controlled, and the transfer machine, back chute and belt cannot be pressed down. Special personnel are assigned to patrol to prevent large coal from blocking the conveyor path.

[0031] like Figure 2 As shown in the figure, in the existing technology, single coal caving leads to uneven top coal caving, the gangue mixing rate is greater than 20%, and the recovery rate is only 60%~70%; like Figure 3 As shown, the multi-round sequential coal discharge of the present invention reduces the gangue mixing rate to <10% and increases the recovery rate to ≥80%; the coal discharge amount is controlled by "closing the door when seeing gangue" to reduce the mixing of gangue, and the recovery rate is greatly improved by controlling the uniformity of coal discharge.

[0032] Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged and the mining equipment is safely in place. The standard for top coal discharge is that only gangue is discharged from the coal outlet for three consecutive rounds without seeing coal flow.

[0033] The present invention also provides a fully-mechanized caving and mining equipment applicable to steeply inclined thick coal seams, which can execute the above-mentioned fully-mechanized caving and mining process applicable to steeply inclined thick coal seams, such as Figure 4 As shown, it includes a hydraulic support 1 and a scraper conveyor 3 placed perpendicular to each other. The base of the hydraulic support 1 is fixedly connected to the trough side of the scraper conveyor 3. The two sides of the top beam of the hydraulic support 1 are fixedly connected to two-way side guard plates 4, and the expansion and contraction are controlled by a hydraulic cylinder. An anti-skid jack 5 is provided between the base of the hydraulic support 1 and the scraper conveyor 3. The other end of the anti-skid jack 5 is connected to the base of the adjacent hydraulic support or the trough side of the scraper conveyor 3 to provide lateral anti-skid force for the hydraulic support 1. A coal shearer 2 is straddled above the scraper conveyor 3, and the coal shearer 2 includes a front drum and a rear drum; A hydraulic anchoring device 6 is fixedly installed at the head or tail of the scraper conveyor 3; the type of the hydraulic anchoring device 6 is selected according to the actual mining operation conditions.

[0034] Example 1 In this embodiment, the coal seam has an inclination angle of 55° and a thickness of 4.0 m. It is applicable to the fully mechanized caving mining process of a steeply inclined thick coal seam, and is specifically implemented in the following steps: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, with a mining-caving ratio of 1:2.6, a mining height of 2.2m, and a coal caving height of 5.8m; Step 2: First coal cutting operation: Each cut depth is 600mm, and the pulling speed is 4.5m / min; Step 3: Move the rack and push forward in sequence; The frame is moved in a grouped, spaced, and cross-type manner. The frame lags behind the drum in the forward direction of the shearer by 10 frames. The frame step is 600mm. The frame is moved in two steps: the first step is 400mm, and the second step is 200mm. The frame is lowered by 200mm. When pushing forward, the front scraper conveyor is pushed in sequence according to the single frame. The length of the curved section is 12m, the horizontal curvature is less than 2°, and the pushing step is 600mm. Step 4: Pull and slide; each group of 10 racks are pulled and slid in sequence along the moving direction at one time, with a step distance of 600mm; Step 5, the second coal cutting operation; the specific steps of the first coal cutting operation are the same as the second coal cutting operation in step 4; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; caving is completed in three rounds, with a single round caving capacity of 30% to 40%; the multi-round sequential caving process begins when the cut is opened, and each round of caving opens the caving ports from one end of the working face to the other in sequence, and closes them when gangue is seen, until all the top coal is caving; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0035] After the fully-mechanized caving and mining operation is completed according to the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams in this embodiment, the recovery rate is 82% and the gangue mixing rate is 8%.

[0036] Example 2 In this embodiment, the coal seam has an inclination angle of 58° and a thickness of 4.5 m. It is applicable to the fully mechanized caving mining process of a steeply inclined thick coal seam, and is specifically implemented in the following steps: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, with a mining-caving ratio of 1:2.7, a mining height of 2.3m, and a coal caving height of 6.2m; Step 2: First coal cutting operation: Each cut depth is 600mm, and the pulling speed is 4.0m / min; Step 3: Move the rack and push forward in sequence; The frame is moved in a grouped, spaced, and cross-type manner. The frame lags behind the drum in the forward direction of the shearer by 10 frames. The frame step is 600mm. The frame is moved in two steps: the first step is 400mm, and the second step is 200mm. The frame is lowered by 200mm. When pushing forward, the front scraper conveyor is pushed in sequence according to the single frame. The length of the curved section during pushing is 13m, the horizontal curvature is less than 2°, and the pushing step is 600mm. Step 4: Pull and slide; each group of 10 racks are pulled and slid in sequence along the moving direction at one time, with a step distance of 600mm; Step 5, the second coal cutting operation; the specific steps of the first coal cutting operation are the same as the second coal cutting operation in step 4; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; caving is completed in three rounds, with a single round caving capacity of 30% to 40%; the multi-round sequential caving process begins when the cut is opened, and each round of caving opens the caving ports from one end of the working face to the other in sequence, and closes them when gangue is seen, until all the top coal is caving; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0037] After the fully-mechanized caving and mining operation is completed according to the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams in this embodiment, the recovery rate is 85% and the gangue mixing rate is 7%.

[0038] Example 3 In this embodiment, the coal seam has an inclination angle of 60° and a thickness of 5.0 m. It is applicable to the fully mechanized caving mining process of a steeply inclined thick coal seam, and is specifically implemented in the following steps: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, with a mining-caving ratio of 1:3.3, a mining height of 2.2m, and a coal caving height of 7.7m; Step 2: First coal cutting operation: Each cut depth is 600mm, and the pulling speed is 4.0m / min; Step 3: Move the rack and push forward in sequence; The frame is moved in a grouped, spaced, and cross-type manner. The frame lags behind the drum in the forward direction of the shearer by 10 frames. The frame step is 600mm. The frame is moved in two steps: the first step is 300mm, and the second step is 300mm. The frame lowering amount is 180mm. When pushing forward, the front scraper conveyor is pushed in sequence according to the single frame. The length of the curved section is 12m, the horizontal curvature is less than 2°, and the pushing step is 600mm. Step 4: Pull and slide; each group of 10 racks are pulled and slid in sequence along the moving direction at one time, with a step distance of 600mm; Step 5, the second coal cutting operation; the specific steps of the first coal cutting operation are the same as the second coal cutting operation in step 4; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; caving is completed in three rounds, with a single round caving capacity of 30% to 40%; the multi-round sequential caving process begins when the cut is opened, and each round of caving opens the caving ports from one end of the working face to the other in sequence, and closes them when gangue is seen, until all the top coal is caving; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0039] After the fully-mechanized caving and mining operation is completed according to the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams in this embodiment, the recovery rate is 83% and the waste rock mixing rate is 9%.

[0040] Example 4 In this embodiment, the coal seam has an inclination angle of 62° and a thickness of 3.8 m. It is applicable to the fully mechanized caving mining process of a steeply inclined thick coal seam, and is specifically implemented in the following steps: Step 1: Select fully mechanized caving mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, with a mining-caving ratio of 1:2.8, a mining height of 2.1m, and a coal caving height of 5.9m; Step 2: First coal cutting operation: Each cut depth is 600mm, and the pulling speed is 4.0m / min; Step 3: Move the rack and push forward in sequence; The frame is moved in a grouped, spaced, and cross-type manner. The frame lags behind the drum in the forward direction of the shearer by 10 frames. The frame step is 600mm. The frame is moved in two steps: the first step is 300mm, and the second step is 300mm. The frame lowering amount is 180mm. When pushing forward, the front scraper conveyor is pushed in sequence according to the single frame. The length of the curved section during pushing is 14m, the horizontal curvature is less than 2°, and the pushing step is 600mm. Step 4: Pull and slide; each group of 10 racks are pulled and slid in sequence along the moving direction at one time, with a step distance of 600mm; Step 5, the second coal cutting operation; the specific steps of the first coal cutting operation are the same as the second coal cutting operation in step 4; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; caving is completed in three rounds, with a single round caving capacity of 30% to 40%; the multi-round sequential caving process begins when the cut is opened, and each round of caving opens the caving ports from one end of the working face to the other in sequence, and closes them when gangue is seen, until all the top coal is caving; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0041] After the fully-mechanized caving and mining operation is completed according to the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams in this embodiment, the recovery rate is 80% and the gangue mixing rate is 10%.

[0042] Example 5 In this embodiment, the coal seam has an inclination angle of 57° and a thickness of 4.2 m. It is applicable to the fully mechanized caving mining process of a steeply inclined thick coal seam, and is specifically implemented in the following steps: Step 1: Select fully mechanized caving mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, with a mining-caving ratio of 1:2.7, a mining height of 2.2m, and a coal caving height of 6.0m; Step 2: First coal cutting operation: Each cut depth is 600mm, and the pulling speed is 4.2m / min; Step 3: Move the rack and push forward in sequence; The frame is moved in a grouped, spaced, and cross-type manner. The frame lags behind the drum in the forward direction of the shearer by 8 frames. The frame step is 600mm. The frame is moved in two steps: the first step is 500mm, and the second step is 200mm. The frame lowering amount is 180mm. When pushing forward, the front scraper conveyor is pushed in sequence according to the single frame. The length of the curved section during pushing is 14m, the horizontal curvature is less than 2°, and the pushing step is 600mm. Step 4: Pull and slide; each group of 10 racks are pulled and slid in sequence along the moving direction at one time, with a step distance of 600mm; Step 5, the second coal cutting operation; the specific steps of the first coal cutting operation are the same as the second coal cutting operation in step 4; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; caving is completed in three rounds, with a single round caving capacity of 30% to 40%; the multi-round sequential caving process begins when the cut is opened, and each round of caving opens the caving ports from one end of the working face to the other in sequence, and closes them when gangue is seen, until all the top coal is caving; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0043] After the fully-mechanized caving and mining operation is completed according to the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams in this embodiment, the recovery rate is 84% ​​and the gangue mixing rate is 8%.

[0044] Example 6 In this embodiment, the coal seam has an inclination of 61° and a thickness of 4.8 m. The fully mechanized top-coal caving mining process is applicable to steeply inclined thick coal seams and is specifically implemented in the following steps: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, with a mining-caving ratio of 1:3.2, a mining height of 2.3m, and a coal caving height of 7.5m; Step 2: First coal cutting operation: Each cut depth is 600mm, and the pulling speed is 4.2m / min; Step 3: Move the rack and push forward in sequence; The frame is moved in a grouped, spaced, and cross-type manner. The frame lags behind the drum in the forward direction of the shearer by 10 frames. The frame step is 600mm. The frame is moved in two steps: the first step is 300mm, and the second step is 300mm. The frame is lowered by 200mm. When pushing forward, the front scraper conveyor is pushed in sequence according to the single frame. The length of the curved section during pushing is 14m, the horizontal curvature is less than 2°, and the pushing step is 600mm. Step 4: Pull and slide; each group of 10 racks are pulled and slid in sequence along the moving direction at one time, with a step distance of 600mm; Step 5, the second coal cutting operation; the specific steps of the first coal cutting operation are the same as the second coal cutting operation in step 4; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; caving is completed in three rounds, with a single round caving capacity of 30% to 40%; the multi-round sequential caving process begins when the cut is opened, and each round of caving opens the caving ports from one end of the working face to the other in sequence, and closes them when gangue is seen, until all the top coal is caving; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

[0045] After the fully-mechanized caving and mining operation is completed according to the fully-mechanized caving and mining process applicable to steeply inclined thick coal seams in this embodiment, the recovery rate is 86% and the gangue mixing rate is 6%.

Claims

1. It is applicable to the fully mechanized caving mining process of steeply inclined thick coal seams, which is characterized by: The mining is carried out in a "two-cut and one-place" cycle mode, which includes two coal cuttings and one coal placing. The specific implementation is as follows: Step 1: Select fully mechanized caving and mining equipment suitable for steeply inclined thick coal seams that meets the process implementation requirements, and determine the mining ratio and mining height; Step 2: First coal cutting operation; Step 3: Move the rack and push forward in sequence; Step 4: Pull back and slide; Step 5: Second coal cutting operation; Step 6. Repeat step 3; Step 7: Use a multi-round sequential caving process to caving top coal; the caving is completed in three rounds, with the caving volume of each round being 30% to 40%; Step 8. Repeat step 4; Step 9: Repeat steps 2 to 8 until the top coal is completely discharged.

2. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 1 is characterized in that: The mining-to-caving ratio is 1:2.6~1:3.3, and the mining height of the working face is 2.1m~2.3m; The process implementation requirements are: The shearer is hauled in a chainless manner with a hauling speed of ≥4.5m / min. The shearer includes a front drum and a rear drum. The support strength of the hydraulic support is ≥0.8MPa, and the initial support force is ≥24MPa; There are multiple hydraulic supports, and the top beams of the hydraulic supports have bidirectional side guard plates. The offset of adjacent hydraulic supports is ≤ 2 / 3 of the height of the side guard plates.

3. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 2 is characterized in that: The specific steps of step 2 are: Step 2-1, parameter setting: each cut depth is 600mm, and the pulling speed is 1.5m / min~4.5m / min; Step 2-2: The coal cutting feed method is oblique cutting feed on the working face; Step 2-3: Cut coal in a downward one-way cutting manner; the front drum of the coal shearer cuts the top coal, and the rear drum cuts the bottom coal.

4. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 2 is characterized in that: The specific implementation parameters of the rack shifting in step 3 include the rack shifting method, rack shifting step distance, rack lowering amount and rack raising requirements; The frame moving method is a grouped and spaced cross type, each group includes two hydraulic supports, and the supports in each group are moved in a sequential manner according to the method of single supports, and the frames are moved in an interlaced manner between the groups, and the distance between the moving supports and the rear roller in the forward direction of the coal mining machine is not more than 10 frames; The step distance of the rack shifting is not less than 600mm; the rack shifting is carried out in two steps, the first step is 300mm~500mm, and the second step is 100mm~300mm; The amount of lowering the rack is not greater than 200 mm; The requirements for lifting the frame are as follows: after lifting, the frame is straight, the skew error is no more than ±50mm, the center distance of the frame is 1500mm±100mm, the top beam of the frame must be parallel to the top plate, and its maximum elevation angle is less than 7°. The height difference between adjacent frames shall not exceed two-thirds of the maximum width of the side guard plate, and ensure that the initial support force is reached, and the distance between the beam ends shall not exceed 400mm.

5. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 2 is characterized in that: The specific steps of pushing the front slide in step 3 are: push the front scraper conveyor in sequence according to the single frame, the length of the curved section during pushing is not less than 12m, the horizontal curvature is less than 2°, and the pushing step is 600mm; when pushing the front slide, it should be pushed while the conveyor is running, and the machine head and tail can be stopped when pushing.

6. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 1 is characterized in that: The specific steps of pulling and sliding in step 4 are: each group of 10 racks are pulled and slid in sequence along the rack moving direction at one time, with a step distance of 600 mm.

7. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 1 is characterized in that: The specific steps of the second coal cutting operation in step 5 are the same as the first coal cutting operation in step 2.

8. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 1 is characterized in that: The specific steps of the multi-round sequential coal placing process are: Multiple rounds of sequential coal discharge start from the time of opening the cut. In each round of coal discharge, the coal discharge ports are opened in sequence from one end of the working face to the other end, and closed when gangue is seen until all the top coal is discharged.

9. The fully mechanized caving mining process applicable to steeply inclined thick coal seams according to claim 1 is characterized in that: The standard for top coal discharge is that only gangue is discharged from the coal discharge port for three consecutive rounds without seeing coal flow.

10. The fully mechanized caving and mining equipment is suitable for steeply inclined thick coal seams, characterized by: A fully mechanized caving and mining process applicable to steeply inclined thick coal seams as claimed in any one of claims 1 to 9 can be implemented, comprising a hydraulic support (1) and a scraper conveyor (3) placed perpendicular to each other, the base of the hydraulic support (1) being fixedly connected to the trough side of the scraper conveyor (3), and two-way side guard plates (4) being fixedly connected on both sides of the top beam of the hydraulic support (1); a coal mining machine (2) is straddling the scraper conveyor (3), and the coal mining machine (2) comprises a front roller and a rear roller; An anti-slip jack (5) is provided between the base of the hydraulic support (1) and the scraper conveyor (3); A hydraulic anchoring device (6) is fixedly installed at the head or tail of the scraper conveyor (3).

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