Roof-cutting Coal-mining Device and Method with Roof Supported by Columns with Offset

Abstract

The present invention discloses a coal mining loss reduction device and method with a column-shaped roof cutting for staggered support of the roof, which includes a single hydraulic prop, a rock mass cutting machine, a first hydraulic support, a second hydraulic support, and a mechanized coal mining device arranged in sequence along the coal mining direction. The rock mass cutting machine includes a cutting tool. One end of the cutting tool is connected to a drill bit, and the other end is connected to a lifting platform. A water stop gasket is provided along the circumferential direction of the cutting tool near the lifting platform. A gear climbing rod is sleeved on the lifting platform. The cutting tool is arranged parallel to the gear climbing rod. The bottom end of the gear climbing rod is fixedly connected to a hydraulic telescopic prop. The inside of the cutting tool is communicated with a hydraulic fracturing water inlet pipe. The hydraulic fracturing water inlet pipe is connected to a power device. The bottom of the power device is fixedly connected to a crawler walking device. The power device is fixedly connected to the lifting platform. The present invention can reduce the number of coal pillars left, improve the recovery rate of coal resources, and the support effect is also stronger than that of coal pillars, which is more conducive to ensuring the safety of the mine.

Description

Technical Field

[0001] The present invention belongs to the technical field of coal mining equipment, and relates to a coal loss reduction mining device with a cutting top as a pillar for offset supporting the roof, and also relates to a coal loss reduction mining method with a cutting top as a pillar for offset supporting the roof. Background Art

[0002] After coal mining in coal mines, there are often a series of problems such as mine water disasters, surface subsidence, and ecological environment damage caused by the collapse of overlying strata. In order to solve this problem, methods such as limited height mining or filling mining have been used in the past.

[0003] The method of limited height mining will increase the loss of coal resources. However, the source of filling materials for filling mining is less, the general mining space in coal mines is large, it is difficult to fill densely, and the strength of the filling materials is generally low, making it difficult to bear the load of the upper strata, and the control effect on the collapse of the upper strata is limited. Summary of the Invention

[0004] The purpose of the present invention is to provide a coal loss reduction mining device with a cutting top as a pillar for offset supporting the roof, which has the characteristics of preventing the collapse of the upper strata and ensuring the safety of the mine;

[0005] Another purpose of the present invention is to provide a coal loss reduction mining method with a cutting top as a pillar for offset supporting the roof.

[0006] One solution of the present invention is that a coal loss reduction mining device with a cutting top as a pillar for offset supporting the roof includes a single hydraulic prop, a rock cutter, a first hydraulic support, a second hydraulic support, and a mechanized coal mining equipment arranged in sequence along the coal mining direction;

[0007] The rock cutter includes a hollow cutting tool. One end of the cutting tool is connected with a drill bit, and the other end is connected with a lifting platform. A water stop gasket is arranged along the circumferential direction of the cutting tool near the lifting platform. A gear climbing rod is sleeved on the lifting platform. The cutting tool is arranged parallel to the gear climbing rod. The bottom end of the gear climbing rod is fixedly connected with a hydraulic telescopic prop. The inside of the cutting tool is communicated with a hydraulic fracturing water inlet pipe. The hydraulic fracturing water inlet pipe is connected with a power device. The bottom of the power device is fixedly connected with a crawler traveling device, and the power device is fixedly connected with the lifting platform; the power device is arranged below the first hydraulic support.

[0008] The feature of the present invention also lies in that: the cutting tool is spirally installed with grinding tool heads.

[0009] Another solution of the present invention is that a coal loss reduction mining method with a cutting top as a pillar for offset supporting the roof includes the following specific steps:

[0010] Step 1: Start the mechanized coal mining equipment to cut the coal seam to be mined in front of the working face and transfer it to the ground to form a goaf;

[0011] Step 2: Arrange the single hydraulic prop, the first hydraulic support, and the second hydraulic support in the goaf in sequence. Place the rock body cutting machine under the first hydraulic support, start the rock body cutting machine to cut the rock to be cut in the goaf, and generate a cut rock pillar.

[0012] Step 3: Shut down the rock body cutting machine, remove the single hydraulic prop, and let the cut rock pillar fall onto the coal seam floor in the goaf.

[0013] Step 4: Use a hook lock to put on the cut rock pillar, and put the other end on the bottom of the rock body cutting machine. After moving the rock body cutting machine to the preset position, untie the hook lock, and let the cut rock pillar support between the coal seam roof and the floor in the goaf to form a rock pillar for supporting the overlying strata.

[0014] Step 5: Repeat the steps of Step 1 to Step 4 to form multiple rock pillars for supporting the overlying strata and distribute them evenly to form a group pillar support system.

[0015] The features of the present invention also lie in that Step 2 is specifically implemented according to the following steps:

[0016] Step 2.1: Support the single hydraulic prop at the lower part of the column body to be cut in the goaf, arrange the rock body cutting machine, the first hydraulic support, and the second hydraulic support in the goaf in sequence, and support the coal seam roof in the goaf.

[0017] Step 2.2: Move the rock body cutting machine to directly below the rock pillar to be cut through the crawler travel device, extend the hydraulic telescopic prop, and support it between the coal seam roof and the floor in the goaf.

[0018] Step 2.3: Adjust the lifting platform to adjust the drill bit to the bottom of the rock pillar to be cut.

[0019] Step 2.4: Start the power device to make the rock body cutting machine start to operate, drill the drill bit to the preset depth, stop and withdraw the drill bit, install a water stop washer at the bottom of the cutting tool, and then lift the lifting platform to make the water stop washer closely adhere to the coal seam roof.

[0020] Step 2.5: Conduct hydraulic fracturing through the hydraulic fracturing water inlet pipe to separate the rock pillar to be cut from the coal seam roof.

[0021] Step 2.6: Adjust the lifting platform, remove the water stop washer, withdraw the cutting tool from the rock stratum, and remove the drill bit.

[0022] Step 2.7: Adjust the lifting platform to make the cutting tool enter the rock pillar to be cut along the original drilling path, and then start the cutting tool to rotate at high speed along the outer contour line of the rock pillar to be cut for one week to separate the rock pillar to be cut from the surrounding rock strata.

[0023] Step 2.8: Adjust the lifting platform to retract the cutting tool from the rock formation, and then retract the single hydraulic prop so that the rock mass cutting machine can move freely.

[0024] Step 2.9: Shut down the power unit to stop the cutting tool from running.

[0025] Step 3 is implemented specifically as follows: Slowly retract the single hydraulic prop to make the cut rock pillar fall slowly. After the single hydraulic prop is fully retracted, withdraw the single hydraulic prop by the traction of the cutting tool.

[0026] The beneficial effects of the present invention are as follows:

[0027] 1. By using dense rock pillars to support the upper rock formation, the present invention reduces the caving and breaking of the rock formation, thereby reducing the disturbance and damage to the ecological environment caused by coal resource mining.

[0028] 2. By using hydraulic fracturing and a cutting tool to quickly cut the rock mass to separate it from the surrounding rock formation, the present invention has high safety in rock formation fragmentation, and the outer contour of the rock pillar is easier to be formed according to the design.

[0029] 3. By using the cut rock pillar to support the upper rock formation, the present invention can reduce the support pressure on the hydraulic support in the working face, which is beneficial to preventing the occurrence of roof accidents.

[0030] 4. By using the cut rock pillar to evenly support the roof rock formation, the present invention can effectively avoid the stress concentration phenomenon at the coal pillar in the working face, thereby reducing the possibility of rock burst, and can also reduce the damage to the overlying aquifer caused by coal seam mining, thereby reducing the underground water inflow, reducing the drainage cost, and reducing the threat of mine water disasters.

[0031] 5. By using the rock mass as the support pillar, the present invention can reduce the number of coal pillars left, thereby improving the recovery rate of coal resources, and the strength of the rock pillar is significantly higher than that of the coal pillar, and the support effect is also stronger than that of the coal pillar, which is more conducive to ensuring the safety of the mine. Description of the Drawings

[0032] Figure 1 is a schematic structural diagram of the coal mining loss reduction device for cutting the top into columns to support the roof in a staggered manner of the present invention;

[0033] Figure 2 is a schematic structural diagram of the rock mass cutting machine in the coal mining loss reduction device for cutting the top into columns to support the roof in a staggered manner of the present invention;

[0034] Figure 3 is a schematic surface diagram of the cutting tool in the coal mining loss reduction device for cutting the top into columns to support the roof in a staggered manner of the present invention;

[0035] Figure 4 is a schematic structural diagram of the single hydraulic prop in the coal mining loss reduction device for cutting the top into columns to support the roof in a staggered manner of the present invention;

[0036] Figure 5 It is a schematic structural diagram of a hydraulic support in a coal mining loss reduction device of the present invention that cuts the top to form columns for offset supporting the roof;

[0037] Figure 6 It is a working principle diagram of a coal mining loss reduction device and method of the present invention that cuts the top to form columns for offset supporting the roof;

[0038] In the figure, 1. Rock mass cutting machine, 101. Cutting tool, 102. Drill bit, 103. Lifting platform, 104. Water stop washer, 105. Gear climbing rod, 106. Hydraulic fracturing water inlet pipe, 107. Power device, 108. Crawler walking device, 2. Single hydraulic prop, 3. Mechanized coal mining equipment, 4. First hydraulic support, 5. Second hydraulic support. Specific embodiments

[0039] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0040] The present invention provides a coal mining loss reduction device that cuts the top to form columns for offset supporting the roof, as Figure 1 shown, including a single hydraulic prop 2, a rock mass cutting machine 1, a first hydraulic support 4, a second hydraulic support 5 and a mechanized coal mining equipment 3 arranged in sequence along the coal mining direction;

[0041] The rock mass cutting machine 1 includes a hollow cutting tool 101. One end of the cutting tool 101 is connected with a drill bit 102, and the other end is connected with a lifting platform 103. A water stop washer 104 is arranged along the circumference of the bottom of the cutting tool 101. A gear climbing rod 105 is sleeved on the lifting platform 103. The cutting tool 101 is arranged parallel to the gear climbing rod 105. The bottom end of the gear climbing rod 105 is fixedly connected with a hydraulic telescopic prop 109. The inside of the cutting tool 101 is communicated with a hydraulic fracturing water inlet pipe 106. The hydraulic fracturing water inlet pipe 106 is connected with a power device 107. The bottom of the power device 107 is fixedly connected with a crawler walking device 108. The power device 107 is fixedly connected with the lifting platform 103; as Figure 3 shown, the cutting tool 101 is spirally installed with dense grinding tool heads on its tool body. The rock mass is quickly cut by using hydraulic fracturing and the cutting tool 101 to separate it from the surrounding rock strata. The height of the cut rock column needs to be controlled to be coordinated with the length and width to make it not easy to tip over.

[0042] The present invention provides a coal mining loss reduction method that cuts the top to form columns for offset supporting the roof, which is specifically implemented according to the following steps:

[0043] Step 1, start the mechanized coal mining equipment 3 to cut the coal seam to be mined in front of the working face and transport it to the ground to form a gob area;

[0044] Step 2: Arrange the single hydraulic prop 2, the first hydraulic support 4, and the second hydraulic support 5 in the goaf in sequence. Place the rock body cutting machine 1 under the first hydraulic support 4, and start the rock body cutting machine 1 to cut the rock to be cut in the goaf to generate a cut rock pillar.

[0045] Step 2.1: Support the single hydraulic prop 2 at the lower part of the column body to be cut in the goaf, and arrange the rock body cutting machine 1, the first hydraulic support 4, and the second hydraulic support 5 in the goaf in sequence to support the coal seam roof in the goaf.

[0046] Step 2.2: Move the rock body cutting machine 1 to directly below the rock pillar to be cut through the crawler travel device 108, and extend the hydraulic telescopic prop 109 to support it between the coal seam roof and floor in the goaf.

[0047] Step 2.3: Adjust the lifting platform 103 to adjust the drill bit 102 to the bottom of the rock pillar to be cut.

[0048] Step 2.4: Start the power device 107 to make the rock body cutting machine 1 start to operate, drill the drill bit 102 to the preset depth, stop and withdraw the drill bit 102, install a water stop washer 104 at the bottom of the cutting tool 101, and then lift the lifting platform 103 to make the water stop washer 104 closely adhere to the coal seam roof.

[0049] Step 2.5: Conduct hydraulic fracturing through the hydraulic fracturing water inlet pipe 106 to separate the rock pillar to be cut from the coal seam roof.

[0050] Step 2.6: Adjust the lifting platform 103, remove the water stop washer 104, withdraw the cutting tool 101 from the rock formation, and remove the drill bit 102.

[0051] Step 2.7: Adjust the lifting platform 103 to make the cutting tool 101 enter the rock pillar to be cut along the original drilling path, and then start the cutting tool 101 to rotate at high speed along the outer contour line of the rock pillar to be cut for one week to separate the rock pillar to be cut from the surrounding rock formations.

[0052] Step 2.8: Adjust the lifting platform 103 to make the cutting tool 101 withdraw from the rock formation, and then contract the single hydraulic prop so that the rock body cutting machine 1 can move freely.

[0053] Step 2.9: Turn off the power device 107 to make the cutting tool 101 stop operating.

[0054] Step 3: Turn off the rock body cutting machine 1, remove the single hydraulic prop 2, and make the cut rock pillar fall onto the coal seam floor in the goaf; slowly contract the single hydraulic prop 2 to make the cut rock pillar slowly fall. After the single hydraulic prop 2 is completely contracted, withdraw the single hydraulic prop 2 by towing with the cutting tool 101.

[0055] Step 4: Put a hook lock on the cut rock pillar, and put the other end on the bottom of the rock mass cutting machine 1. After moving the rock mass cutting machine 1 to the preset position, unlock the hook lock so that the cut rock pillar supports between the coal seam roof and floor in the goaf, forming a rock pillar to support the overlying strata.

[0056] Step 5: Repeat the steps of Step 1 to Step 4 to form multiple rock pillars to support the overlying strata and distribute them evenly to form a group pillar support system.

[0057] The present invention provides a coal mining loss reduction device and method with roof cutting as pillars for staggered support of the roof. The advantages are as follows: Using rock mass as the support pillar can reduce the number of reserved coal pillars, thereby improving the recovery rate of coal resources. Moreover, the strength of the rock pillar is significantly higher than that of the coal pillar, and the support effect will also be stronger than that of the coal pillar, which is more conducive to ensuring the safety of the mine.

Claims

1. The coal mining device with reduced loss by using a roof cutting and column setting for staggered support of the roof, characterized in that, It includes a single hydraulic prop (2), a rock mass cutting machine (1), a first hydraulic support (4), a second hydraulic support (5) and a mechanized coal mining equipment (3) arranged successively along the coal mining direction; The rock mass cutting machine (1) includes a hollow cutting tool (101). One end of the cutting tool (101) is connected with a drill bit (102), and the other end is connected with a lifting platform (103). A water stop gasket (104) is arranged along the circumferential direction of the cutting tool (101) near the lifting platform (103). A gear climbing rod (105) is sleeved on the lifting platform (103). The cutting tool (101) is arranged parallel to the gear climbing rod (105). The bottom end of the gear climbing rod (105) is fixedly connected with a hydraulic telescopic prop (109). The inside of the cutting tool (101) is communicated with a hydraulic fracturing water inlet pipe (106). The hydraulic fracturing water inlet pipe (106) is connected with a power device (107). The bottom of the power device (107) is fixedly connected with a crawler traveling device (108). The power device (107) is fixedly connected with the lifting platform (103); the power device (107) is arranged on the side of the first hydraulic support (4).

2. The coal mining device according to claim 1, characterized in that, The cutting tool (101) is spirally installed with grinding heads.

3. A coal mining method for reducing losses by cutting the top as columns to support the roof staggeredly, characterized in that, This method uses the coal mining loss reduction device described in any one of claims 1-2. The specific steps are as follows: Step 1: Start the mechanized coal mining equipment (3) to cut the coal seam to be mined in front of the working face and transport it to the ground to form a goaf; Step 2: Arrange the single hydraulic prop (2), the rock mass cutting machine (1), the first hydraulic support (4), and the second hydraulic support (5) in the goaf in sequence. Start the rock mass cutting machine (1) to cut the rock to be cut in the goaf to generate a cut rock pillar; Step 3: Shut down the rock mass cutting machine (1), remove the single hydraulic prop (2), and make the cut rock pillar fall on the coal seam floor in the goaf; Step 4: Use a hook lock to put it on the cut rock pillar, and the other end is put on the bottom of the rock mass cutting machine (1). After moving the rock mass cutting machine (1) to a preset position, unlock the hook lock to make the cut rock pillar support between the coal seam roof and floor in the goaf to form a rock pillar for supporting the overlying strata; Step 5: Repeat the steps of Step 1 to Step 4 to form multiple rock pillars for supporting the overlying strata and distribute them evenly to form a group pillar support system.

4. The coal mining method according to claim 3, wherein The specific implementation of Step 2 is as follows: Step 2.1: Support the single hydraulic prop (2) under the lower part of the pillar to be cut in the goaf, and arrange the rock mass cutting machine (1), the first hydraulic support (4) and the second hydraulic support (5) in the goaf in sequence to support the coal seam roof in the goaf; Step 2.2: Move the rock mass cutting machine (1) to directly below the rock pillar to be cut through the crawler traveling device (108), and extend the hydraulic telescopic prop (109) to support between the coal seam roof and floor in the goaf; Step 2.3: Adjust the lifting platform (103) to adjust the drill bit (102) to the bottom of the rock pillar to be cut; Step 2.4: Start the power device (107) to make the rock mass cutting machine (1) start running. Drill the drill bit (102) to the preset depth, stop and withdraw the drill bit (102). Install a water stop gasket (104) at the bottom of the cutting tool (101), and then raise the lifting platform (103) to make the water stop gasket (104) closely adhere to the coal seam roof; Step 2.5: Conduct hydraulic fracturing through the hydraulic fracturing water inlet pipe (106) to separate the rock pillar to be cut from the coal seam roof; Step 2.6: Adjust the lifting platform (103), remove the water stop gasket (104), withdraw the cutting tool (101) from the rock formation, and remove the drill bit (102); Step 2.7: Adjust the lifting platform (103) to make the cutting tool (101) enter the rock pillar to be cut along the original drilling path. Then start the cutting tool (101) and rotate it at high speed along the outer contour line of the rock pillar to be cut for one week to separate the rock pillar to be cut from the surrounding rock formations; Step 2.8: Adjust the lifting platform (103) to make the cutting tool (101) withdraw from the rock formation, and then contract the single hydraulic prop (2) to make the rock mass cutting machine (1) move freely; Step 2.9: Shut down the power device (107) to stop the cutting tool (101) from running.

5. The coal mining method according to claim 3, characterized in that The specific implementation of Step 3 is as follows: Slowly contract the single hydraulic prop (2) to make the cut rock pillar slowly fall. After the single hydraulic prop (2) is completely contracted, withdraw the single hydraulic prop (2) by the traction of the cutting tool (101).

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