A natural caving method mining area boundary induced caving pre-splitting drilling combined device and its operation method

Abstract

The application discloses a kind of natural caving method mining area boundary induced caving pre-splitting drilling combination device and its operating method, device includes vertical box and symmetric drilling combination part, drilling combination part is equipped with motor, runner, two-stage hydraulic cylinder, casing and closed pull rope with scraper block, matched pressurized dust removal mechanism, bottom mobile support structure and built-in PLC hydraulic control system.By hydraulic cylinder, the span of pull rope and operation height can be adjusted in both directions, flexible pull rope is adapted to inverted V-shaped special-shaped through hole, and pre-splitting is realized by hard scraper block to cycle scraping rock mass without blasting explosive device.When operating, first form inverted V-shaped underground communication borehole, after adjusting the span tension of rope body, motor drives scraper block to continuously break, synchronous high-pressure ventilation and dust removal, and the rope body is layered and lowered to expand the hole.The application eliminates the safety hazard of blasting, can be flexibly transported underground, adapts to the complex boundary profile of mining area, has low construction cost, high degree of automation, and effectively solves the problems of vibration, poor adaptability and other problems existing in traditional blasting and rigid cutting process.

Description

Technical Field

[0001] This invention belongs to the field of underground metal mining technology, specifically relating to a pre-splitting borehole assembly device and its operation method suitable for natural caving mining scenarios and used for inducing caving formation at the mining area boundary. Background Technology

[0002] Natural caving is a low-cost, large-scale, and efficient mining technique for thick metallic ore bodies. The core of this method relies on bottom grouting and cutting, followed by the natural fracturing and caving of the ore body driven by its own weight and geostress. During mining operations, the quality of the boundary formation directly determines the ore recovery rate and underground mining safety. It is necessary to create a continuous and regular pre-fractured isolation surface at the interface between the ore body and the surrounding rock to control the caving range and prevent large amounts of waste rock from entering the mining area or causing under-excavation of the boundary and ground pressure instability.

[0003] Currently, the mainstream boundary pre-fracture induction methods in the industry are divided into three categories: fan-shaped deep-hole blasting, dense bundled borehole weakening, and large-scale mechanical sawing. Fan-shaped deep-hole blasting relies on explosives to generate stress cracks, resulting in large blasting vibrations that can easily damage surrounding support roadways and underground equipment. It also poses safety hazards such as duds and fumes poisoning. The direction of the cracks is difficult to control precisely, and over-excavation or under-excavation is very likely to occur. Dense bundled boreholes weaken the rock mass by relying on dense holes, but the drilling workload is huge, the drilling efficiency in hard rock strata is low, and the cost of drill bit consumables is high. Large-scale mechanical cutting equipment has high cutting precision, but the overall size of the machine is large. The boundary working space in deep high-pressure mining areas is narrow, making it difficult to bring the equipment to the site, and the purchase and maintenance costs are high.

[0004] The aforementioned traditional solutions all suffer from drawbacks such as high safety risks, high construction costs, and poor adaptability to complex curved surface boundaries. In particular, for deep V-shaped and inverted V-shaped boundary strata, straight drilling and rigid cutting equipment cannot conform to the stratum contour to form a continuous pre-splitting channel. Summary of the Invention

[0005] The main technical problem to be solved by the present invention is to provide a pre-splitting borehole combination device and its operation method for inducing caving at the boundary of a mining area using the natural caving method, which overcomes the shortcomings of existing mining area boundary induced caving processes, such as large blasting safety hazards, rigid equipment that cannot be adapted to complex inverted V-shaped channels, and high construction material and operation and maintenance costs.

[0006] To solve the above-mentioned technical problems, the present invention provides a pre-splitting drilling assembly for inducing caving at the boundary of a mining area using the natural caving method, comprising a vertical box and two sets of drilling assembly parts symmetrically installed on the top surface of the vertical box.

[0007] Each drilling assembly includes a vertical plate and a support frame. The vertical plate is fixed vertically to the surface of the vertical box, and the support frame is horizontally fixed to the lower part of the vertical plate. A drive motor is fixedly installed on the top of the vertical plate, and a rotating wheel is coaxially fixedly mounted on the output shaft of the motor. A first hydraulic cylinder is vertically arranged in the center of the support frame. The top of the first piston rod of the first hydraulic cylinder is rigidly connected to the support tube. A fixed crossbar is horizontally inserted inside the support tube. Hollow square blocks are symmetrically installed at the left and right ends of the crossbar. A connecting rod is movably inserted into the block, and a first sleeve is fixed to the outer end of the connecting rod. Second hydraulic cylinders are symmetrically arranged horizontally on the left and right sides of the support frame. The second piston rod of the second hydraulic cylinder extends outward, and a second sleeve is fixed to the end of the piston rod.

[0008] Within the same drilling assembly, a closed loop pull rope is threaded between the rotary wheel, the first casing on both sides, and the second casing on both sides. Several scraper blocks are evenly fixed on the outer surface of the pull rope along its length. A pressure pump is fixedly installed on the vertical plate and below the motor, and the output end of the pressure pump is connected to a vent pipe.

[0009] In a preferred embodiment, casters are installed at all four corners of the bottom of the upright box, and a height-adjustable support foot is vertically threaded at the center of the bottom surface of the upright box.

[0010] In a preferred embodiment, the scraper block is a triangular hard steel component; the pull rope is made of steel wire rope base, and the steel wire rope is entirely covered with a wear-resistant protective coating; an annular groove adapted to the shape of the pull rope is opened on the outer periphery of the wheel, and anti-slip texture is processed on the inner wall of the groove.

[0011] In a preferred embodiment, the end of the vent pipe is fitted with an annular jet nozzle, which is arranged around the outside of the borehole inlet.

[0012] In a preferred embodiment, the internal space of the vertical box is divided into a hydraulic station and an electrical control cabinet; the hydraulic station is connected to all the first hydraulic cylinders and the second hydraulic cylinders through independent pressure oil circuits; the control cabinet integrates a PLC controller, which is electrically connected to the drive motor, the pressurization pump, and the electrical control components of the hydraulic station.

[0013] In a preferred embodiment, a threaded hole is provided on the side wall of the card block, and a fastening screw is installed in the threaded hole. The end of the fastening screw presses against the connecting rod to achieve locking and positioning. The crossbar and the support tube are rigidly fixed by welding or bolting, and the connecting rod can slide horizontally along the inner cavity of the card block.

[0014] The present invention also provides an operating method based on the pre-splitting drilling assembly as described above, comprising the following steps:

[0015] Step 1: Use the casters at the bottom of the vertical box to move the whole machine to the preset construction point at the boundary of the mining area. Rotate the center of the vertical box to lift the support legs to tighten them on the ground. Use a level to complete the horizontal calibration of the whole machine and clean the loose slag and gravel around the borehole entrance.

[0016] Step 2: Drill two inclined boreholes along the design outline of the mining area boundary. The two boreholes extend into the depth and connect with each other at the target collapse location to form an inverted V-shaped underground connecting channel.

[0017] Step 3: Start the hydraulic station to control the synchronous extension and retraction of the two sets of second hydraulic cylinders, driving the second casing to move horizontally, and adjust the horizontal span of the pull rope according to the distance between the surface openings of the two boreholes; control the first hydraulic cylinder to raise and lower the support pipe, raising the crossbar to the preset working height;

[0018] Step 4: Pass the closed pull rope with scraper through the surface borehole on one side, the inverted V-shaped underground through-hole, and the surface borehole on the other side in sequence. Let the two ends of the pull rope go around to the annular groove on the outer circumference of the wheel; pull the connecting rod to slide in the locking block, adjust the overall tension of the pull rope, and tighten the fastening screws on the side wall of the locking block to lock the position of the connecting rod.

[0019] Step 5: The PLC controller starts the drive motor to rotate the wheel at low speed, and fine-tunes to eliminate the slack section of the pull rope, so that the outer scraper of the pull rope is completely in contact with the inner wall of the lower side of the channel.

[0020] Step Six: Keep the motor running at a constant speed. The wheel drives the closed pull rope to circulate back and forth in the inverted V-shaped channel. The scraper continuously scrapes and impacts the rock on the hole wall. At the same time, start the pressurization pump. The high-pressure airflow is continuously delivered into the borehole through the ventilation pipe and the ring jet nozzle to complete the dust removal and cooling inside the hole.

[0021] Step 7: The PLC controller controls the first hydraulic cylinder to slowly lower the support pipe, gradually lower the crossbar, extend the effective breaking section of the pull rope, and continuously expand the breaking section of the channel until the channel size reaches the design standard for induced collapse; after the operation is completed, the pull rope is retrieved, the equipment is released from fixation and transported to the next construction point.

[0022] In a preferred embodiment, in step seven, the lowering speed of the first hydraulic cylinder is controlled by the PLC controller to match the rock crushing progress on site.

[0023] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0024] 1. This invention abandons the explosive blasting operation mode and relies entirely on the mechanical friction crushing of hard scrapers carried by steel wire ropes. No detonators or explosives are required for underground operations, completely eliminating the safety hazards of blasting vibration, surrounding rock instability, duds, and blasting smoke poisoning. It is suitable for underground mining sites with high ground temperature, high gas, and vibration sensitivity.

[0025] 2. This invention uses a flexible ring-shaped steel wire rope as the crushing carrier, which can completely fit into the irregular underground through-holes of inverted V-shape and zigzag shape. With the help of two sets of hydraulic cylinders, it can realize the horizontal and vertical bidirectional size adjustment, which can adapt to the boundary holes of mining areas with different spans and depths, and solve the limitation of traditional rigid cutting equipment that can only carry out linear construction. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall external structure of the device of the present invention;

[0027] Figure 2 This is an enlarged structural diagram of the single-group drilling assembly of the present invention;

[0028] Figure 3 This is a top view of the bottom support structure of the upright box of the present invention;

[0029] Reference numerals: 1-Upright box, 2-Ventilation pipe, 3-Pressure pump, 4-Horizontal bar, 5-First sleeve, 6-Pull rope, 7-Scraper block, 8-Motor, 9-Upright plate, 10-Roller, 11-Support pipe, 12-First piston rod, 13-First hydraulic cylinder, 14-Clamping block, 15-Connecting rod, 16-Second sleeve, 17-Second piston rod, 18-Second hydraulic cylinder, 19-Support frame, A-Drilling assembly. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0031] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," and "left," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0034] The following is in conjunction with the appendix Figure 1-3 This paper provides a detailed and extended description of the overall structure, assembly relationship of each component, adjustment logic, and supporting control system of the pre-splitting borehole combination device for inducing caving at the boundary of the mining area using the natural caving method of the present invention. At the same time, it fully elaborates on the standardized operation process for inducing caving at the boundary of the mining area using this device. All structural features and operation logic are extended and detailed based on the structure of the disclosure record, which is different from the brief implementation description in the disclosure.

[0035] The main body of the pre-splitting drilling assembly for the natural caving method of mining boundary induced caving consists of a vertical box 1 and two sets of symmetrically arranged drilling assemblies A. The two sets of drilling assemblies are mirror images mounted on the upper surface of the vertical box. The two sets of structural parameters and adjustment mechanisms are completely identical, and can be adapted to the drilling construction needs of both sides of the mining area simultaneously. The single-sided drilling assembly uses the vertical plate 9 as the vertical installation base, and the support frame 19 is horizontally fixed to the lower half of the vertical plate. The two form a stable load-bearing frame through fasteners. The entire rope crushing actuator is integrated in the space enclosed by the vertical plate and the support frame. Disassembly and maintenance only require single-sided operation, without the need to disassemble the entire machine.

[0036] The motor 8 is fixedly installed at the top of the upright plate 9. The output shaft of the motor extends horizontally and is coaxially locked to assemble the wheel 10. The outer ring of the wheel 10 is machined with an annular groove, and the inside of the groove is provided with anti-slip texture. The cross-sectional dimensions of the annular groove are completely matched with the outer diameter of the pull rope 6, which can limit the lateral displacement of the pull rope 6 during operation, prevent the rope from coming off the wheel during high-speed cyclic motion, and ensure transmission stability.

[0037] A first hydraulic cylinder 13 is vertically mounted at the geometric center of the support frame 19. The first hydraulic cylinder is equipped with an upwardly extending first piston rod 12. The top of the piston rod is rigidly connected to the bottom of the support tube 11. A horizontal crossbar 4 is horizontally mounted inside the support tube 11. There is no relative sliding between the crossbar 4 and the support tube 11, forming an integrated lifting load-bearing beam structure. Hollow square-shaped locking blocks 14 are symmetrically mounted at both ends of the crossbar 4. Through-threaded holes are opened on the side walls of the locking blocks 14, and fastening screws are installed in the threaded holes. A horizontally sliding connecting rod 15 passes through the inner cavity of the locking blocks 14. Tightening the fastening screws presses the outer wall of the connecting rod, locking the extension length of the connecting rod. This allows for flexible adjustment of the horizontal distance between the first sleeves 5 on both sides, adapting to different orifice lateral distances. The outer end of the connecting rod 15 is fixed to the first sleeve 5. A smooth rope passage is reserved inside the sleeve to reduce frictional loss during the reciprocating motion of the rope.

[0038] The second hydraulic cylinders 18 are arranged horizontally and symmetrically on the left and right sides of the support frame 19. The second hydraulic cylinders extend the second piston rod 17 outward, and the end of the piston rod is rigidly fixed to the second sleeve 16. The two sets of second hydraulic cylinders on the left and right can extend and retract synchronously, thereby driving the second sleeves on both sides to expand outward or retract inward synchronously, so as to adjust the bottom lateral span of the entire closed pull rope system and adapt to the surface opening spacing of different inclined boreholes in the mining area.

[0039] A complete closed loop pull rope 6 is threaded through the rotating wheel 10, the first sleeves 5 on the left and right sides, and the second sleeves 6 on the left and right sides. The base of the pull rope is a steel wire rope, and the outside is fully covered with a wear-resistant protective coating. Multiple triangular hard steel scraper blocks 7 are evenly spaced along the length of the pull rope, with the sharp corners of the scraper blocks facing outwards. When the rope is in cyclical motion, it continuously scrapes and impacts the rock wall of the channel, breaking it. The triangular structure can simultaneously achieve the dual crushing effects of extrusion peeling and friction grinding.

[0040] A pressure pump 3 is fixedly installed on the surface of the vertical plate 9 and below the motor 8. The output end of the pressure pump is connected to the air pipe 2. The end of the air pipe is equipped with an annular air nozzle. The annular air nozzle is arranged around the borehole entrance. During the operation, high-pressure airflow is continuously introduced into the borehole to remove the rock powder and heat generated by the friction of the scraper in time, so as to avoid dust accumulation and blockage of the borehole, and high temperature wear of the rope and scraper.

[0041] The vertical box 1 serves as the base for the entire machine. It is equipped with casters at the four corners of the bottom, which can be used to move the entire machine tracklessly to any boundary point of the mining area underground. The vertical box is equipped with a vertically threaded support foot at the center of the bottom surface. After the equipment is moved into place, the support foot is unscrewed to make it completely fit with the ground. The level is then used to correct the horizontal state of the entire machine, which can offset the tilting problem caused by the uneven ground underground and ensure that the rope breaking trajectory fits the designed channel direction.

[0042] The vertical box is divided into two independent storage chambers, which house the hydraulic station and the electrical control cabinet respectively. The hydraulic station is connected to all the first hydraulic cylinders 13 and the second hydraulic cylinders 18 through independent oil circuits, and can control the extension and retraction stroke of any group of hydraulic cylinders individually. The control cabinet integrates a PLC controller, which is electrically connected to the motor 8, the pressurizing pump 3, and the electrical control components of the hydraulic station. It can uniformly preset and automatically adjust the motor speed, the lifting speed of the hydraulic rod, and the air supply pressure of the pressurizing pump, so as to realize the fully automated control of the crushing operation without the need for real-time manual operation.

[0043] When the entire set of equipment is used for induced caving operations at the boundary of a mining area using the natural caving method, the complete operation process consists of seven consecutive procedures, with additional details on operating condition adjustments for each procedure:

[0044] The first step is underground transport and equipment fixation. The entire machine is pushed to the designed construction point at the boundary of the mining area using the universal wheels at the bottom of the vertical box. The point selection ensures that the two sets of borehole combinations correspond to the two designed pre-splitting boreholes on the left and right sides of the mining area, respectively. The lifting support foot in the center of the vertical box is fully supported on the ground. The extension length of the support foot is repeatedly adjusted with the help of a level to keep the whole machine level. Scattered slag and large pieces of gravel around the borehole entrance are manually cleaned to prevent stones from blocking the path of the rope.

[0045] The second step involves pre-splitting borehole formation, where two inclined boreholes are constructed along the pre-defined boundary of the mining area. The boreholes extend downwards and deeper, and the two boreholes intersect and connect at the target induced collapse location, forming an inverted V-shaped underground connecting channel. The inner wall of the channel remains continuous and intact, without large-area collapse areas, ensuring that subsequent guy ropes can pass through intact.

[0046] The third step involves pre-adjusting the span and height. The hydraulic station inside the vertical box is activated, and the extension and retraction of the second hydraulic cylinders on the left and right sides are controlled simultaneously to drive the second casing to move horizontally. Based on the actual measured distance between the surface openings of the two boreholes, the horizontal span at the bottom of the entire closed pull rope system is precisely adjusted. Then, the first hydraulic cylinder is controlled to lift the support pipe, raising the crossbar to the preset initial working height, leaving room for subsequent downward hole expansion adjustment.

[0047] The fourth step involves the installation and tensioning of the closing pull rope. The closing pull rope with the pre-installed scraper block is passed sequentially through the surface borehole on one side, the inverted V-shaped underground through-hole, and the surface borehole on the other side. The two ends of the pull rope are wound into the annular anti-slip groove on the outer ring of the rotating wheel 10. The connecting rod 15 is manually pulled to slide horizontally in the inner cavity of the locking block 14. The lateral distance between the first sleeves on both sides is finely adjusted to adjust the overall tension of the pull rope to a suitable state, completely eliminating the slack and sagging section. The fastening screws on the side wall of the locking block are tightened to lock the position of the connecting rod and prevent the tension from shifting during the operation.

[0048] The fifth step is pre-running calibration. The PLC controller sends a low-speed running command to the motor, which drives the wheel to rotate slowly. The low-speed cycle drives the rope to move back and forth slightly. The rope running status at the orifice is observed manually to confirm that the scraper is completely in contact with the rock wall on the lower side of the orifice, without any suspension or jamming. If there is any slack, the locking position of the connecting rod is finely adjusted again.

[0049] The sixth step involves continuous mechanical crushing and synchronous ventilation and dust removal. The motor is switched to the preset uniform speed working position, and the wheel continuously drives the closed pull rope to move in a closed loop within the inverted V-shaped channel. The hard triangular scraper repeatedly scrapes and impacts the rock wall of the channel, continuously generating fatigue cracks on the rock wall surface and peeling off rock blocks. At the same time, the pressure pump is started, and the high-pressure airflow is delivered to the annular jet nozzle at the orifice through the ventilation pipe, continuously sending air into the channel to discharge the rock powder generated by crushing in real time. At the same time, it reduces the temperature generated by the friction between the scraper and the rock wall, extending the service life of the rope and the scraper.

[0050] In the seventh step, layered hole enlargement and work completion, the PLC controller slowly lowers the first hydraulic cylinder at a preset rate, driving the support pipe and crossbar to move downwards synchronously, gradually extending the effective crushing section of the pull rope into the underground tunnel, and expanding the cross-sectional size of the inverted V-shaped tunnel layer by layer from top to bottom, until the tunnel width and penetration reach the design standard for induced collapse at the mining area boundary; after all crushing operations are completed, the motor and pressure pump are stopped, the locking block fastening screws are loosened, the pull rope is retracted, the support legs are rotated back, and the entire machine is transferred to the next construction point using the casters.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A pre-splitting drilling assembly for inducing caving at the boundary of a mining area using a natural caving method, characterized in that, It includes a vertical box and two sets of drilled assembly parts symmetrically installed on the top surface of the vertical box; Each drilling assembly includes a vertical plate and a support frame. The vertical plate is fixed vertically to the surface of the vertical box, and the support frame is horizontally fixed to the lower part of the vertical plate. A drive motor is fixedly installed on the top of the vertical plate, and a rotating wheel is coaxially fixedly mounted on the output shaft of the motor. A first hydraulic cylinder is vertically arranged in the center of the support frame. The top of the first piston rod of the first hydraulic cylinder is rigidly connected to the support tube. A fixed crossbar is horizontally inserted inside the support tube. Hollow square blocks are symmetrically installed at the left and right ends of the crossbar. A connecting rod is movably inserted into the block, and a first sleeve is fixed to the outer end of the connecting rod. Second hydraulic cylinders are symmetrically arranged horizontally on the left and right sides of the support frame. The second piston rod of the second hydraulic cylinder extends outward, and a second sleeve is fixed to the end of the piston rod. Within the same drilling assembly, a closed loop pull rope is threaded between the rotary wheel, the first casing on both sides, and the second casing on both sides. Several scraper blocks are evenly fixed on the outer surface of the pull rope along its length. A pressure pump is fixedly installed on the vertical plate and below the motor, and the output end of the pressure pump is connected to a vent pipe.

2. The pre-splitting drilling assembly for inducing caving at the boundary of a mining area using the natural caving method according to claim 1, characterized in that, The four corners of the bottom of the upright box are equipped with casters, and the center of the bottom surface of the upright box is threaded with a height-adjustable support foot.

3. The pre-splitting drilling assembly for inducing caving at the boundary of a mining area using the natural caving method according to claim 1, characterized in that, The scraper is a triangular hard steel component; the pull rope is made of steel wire rope base, and the outside of the steel wire rope is covered with a wear-resistant protective coating; the outer circumference of the wheel is provided with an annular groove that matches the shape of the pull rope, and the inner wall of the groove is processed with anti-slip texture.

4. The pre-splitting drilling assembly for inducing caving at the boundary of a mining area using the natural caving method according to claim 1, characterized in that, The end of the vent pipe is equipped with an annular air nozzle, which is arranged around the outside of the borehole inlet.

5. The pre-splitting drilling assembly for inducing caving at the boundary of a mining area using the natural caving method according to claim 1, characterized in that, The internal space of the vertical box is divided into a hydraulic station and an electrical control cabinet; the hydraulic station is connected to all the first hydraulic cylinders and the second hydraulic cylinders through independent pressure oil circuits; the control cabinet integrates a PLC controller, which is electrically connected to the drive motor, the pressurization pump, and the electrical control components of the hydraulic station.

6. The pre-splitting drilling assembly for inducing caving at the boundary of a mining area using the natural caving method according to claim 1, characterized in that, The side wall of the card block has a threaded hole, and a fastening screw is installed in the threaded hole. The end of the fastening screw presses against the connecting rod to achieve locking and positioning. The crossbar and the support tube are rigidly fixed by welding or bolting, and the connecting rod can slide horizontally along the inner cavity of the card block.

7. An operating method for the pre-splitting drilling assembly according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1: Use the casters at the bottom of the vertical box to move the whole machine to the preset construction point at the boundary of the mining area. Rotate the center of the vertical box to lift the support legs to tighten them on the ground. Use a level to complete the horizontal calibration of the whole machine and clean the loose slag and gravel around the borehole entrance. Step 2: Drill two inclined boreholes along the design outline of the mining area boundary. The two boreholes extend into the depth and connect with each other at the target collapse location to form an inverted V-shaped underground connecting channel. Step 3: Start the hydraulic station to control the synchronous extension and retraction of the two sets of second hydraulic cylinders, driving the second casing to move horizontally, and adjust the horizontal span of the pull rope according to the distance between the surface openings of the two boreholes; control the first hydraulic cylinder to raise and lower the support pipe, raising the crossbar to the preset working height; Step 4: Pass the closed pull rope with scraper through the surface borehole on one side, the inverted V-shaped underground through-hole, and the surface borehole on the other side in sequence. Let the two ends of the pull rope go around to the annular groove on the outer circumference of the wheel; pull the connecting rod to slide in the locking block, adjust the overall tension of the pull rope, and tighten the fastening screws on the side wall of the locking block to lock the position of the connecting rod. Step 5: The PLC controller starts the drive motor to rotate the wheel at low speed, and fine-tunes to eliminate the slack section of the pull rope, so that the outer scraper of the pull rope is completely in contact with the inner wall of the lower side of the channel. Step Six: Keep the motor running at a constant speed. The wheel drives the closed pull rope to circulate back and forth in the inverted V-shaped channel. The scraper continuously scrapes and impacts the rock on the hole wall. At the same time, start the pressurization pump. The high-pressure airflow is continuously delivered into the borehole through the ventilation pipe and the ring jet nozzle to complete the dust removal and cooling inside the hole. Step 7: The PLC controller controls the first hydraulic cylinder to slowly lower the support pipe, gradually lower the crossbar, extend the effective breaking section of the pull rope, and continuously expand the breaking section of the channel until the channel size reaches the design standard for induced collapse; after the operation is completed, the pull rope is retrieved, the equipment is released from fixation and transported to the next construction point.

8. The method for inducing caving at the boundary of a mining area using the natural caving method according to claim 7, characterized in that, In step seven, the lowering speed of the first hydraulic cylinder is controlled by the PLC controller to match the rock crushing progress on site.

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