Directional hydraulic fracturing coal seam pressure relief and permeability increasing device and permeability increasing method

Abstract

The invention relates to the technical field of hydraulic fracturing coal seams, and discloses a directional hydraulic fracturing coal seam pressure relief and permeability increasing device and a permeability increasing method. Comprising a spalling device, movable plates are fixedly connected to the front surface and the rear surface of the spalling device, an external expansion plate is movably connected to the lower surface of each movable plate through a shaft rod, a first bearing seat is fixedly connected to the rear surface of each external expansion plate, and a hollow pipe is movably connected to the lower surface of each first bearing seat through a bearing; an external expansion plate capable of expanding outwards is supported through a hollow pipe and a telescopic rod, recovery of the external expansion plate caused by collapse of a coal seam is prevented, a plugging block is tightly attached to the position of a water outlet hole in the inner wall of the spalling device, the water outlet hole is directly plugged, and when upward thrust generated by water pressure is larger than upward supporting force of a second spring, the water outlet hole is plugged. And the sealing fit state of the lower transverse plate and the water outlet hole is relieved, and the water outlet hole is completely opened, so that external coal slag can be prevented from entering the spalling device to block the water outlet hole.

Description

Technical Field

[0001] This invention relates to the field of hydraulic fracturing of coal seams, specifically to a directional hydraulic fracturing coal seam depressurization and permeability enhancement device and method. Background Technology

[0002] The directional hydraulic fracturing coal seam pressure relief and permeability enhancement device is a special equipment used for coal mine gas control. It forms a directional fracture network in the coal seam through the action of high-pressure fluid, thereby improving the permeability of the coal seam and enhancing the gas extraction effect.

[0003] Some existing devices cannot provide additional support for coal seam collapse when fracturing coal seams, causing the outer expansion of the fracturing device to easily shrink and reset, which reduces the device's fracturing effect on coal seams. At the same time, when the coal seam is subjected to high-pressure water spraying, the water outlet holes on the surface of the fracturing device are not blocked, which allows coal slag from the coal seam to easily enter the water outlet holes and cause blockage, preventing the high-pressure water spraying from being carried out normally. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a directional hydraulic fracturing coal seam depressurization and permeability enhancement device and method. A hydraulic medium is injected into the hollow tube through a gas pipe fixedly connected to it. As the internal pressure of the hollow tube increases, it pushes a piston slidably connected inside the tube to move outward. Since the left end of the telescopic rod is fixedly connected to the fracturing device via a second bearing seat, the outward movement of the piston will, in turn, cause the entire hollow tube to extend outward. The hollow tube is fixedly connected to an outer expansion plate via a first bearing seat; therefore, the extension of the hollow tube will drive the outer expansion plate to rotate... The shaft rotates, while the movable plate is fixed to the front and rear surfaces of the fracturing device, effectively fixing the rotation fulcrum of the expansion plate. This ultimately causes the expansion plate to open in the preset directional fracturing direction. During this opening process, its outer surface exerts a directional compressive force on the coal seam borehole wall, forcing the coal seam to generate initial micro-fractures in that direction. Simultaneously, the rotation of the expansion plate stretches the first spring fixed to it, allowing the spring to store elastic potential energy. The hollow tube and telescopic rod then support the expanding plate, preventing coal seam collapse and subsequent plate retraction. When no high-pressure water is introduced, the second spring is in a naturally supported state, with its top fixed to the inner wall of the fracturing device and its bottom fixed to the horizontal plate. The horizontal plate applies an upward supporting force to the sealing block, causing the sealing block to fit tightly against the water outlet position on the inner wall of the fracturing device, directly sealing the water outlet and preventing premature leakage of the subsequently introduced high-pressure water. The rubber block on the outer surface of the sealing block and the rubber rod embedded inside further enhance the sealing effect. The rubber block uses the elastic deformation of rubber to fill the gap between the sealing block and the inner wall of the fracturing device and the edge of the water outlet, while the rubber rod enhances the structural strength of the rubber block. To prevent the rubber block from excessively deforming and failing due to subsequent high-pressure extrusion, and to ensure that a stable high-pressure environment can be established inside the fracturing device, as the internal water pressure gradually increases, the high-pressure water generates an upward thrust on the sealing block. When the upward thrust generated by the water pressure is greater than the upward supporting force of the second spring, the sealing block overcomes the elastic force of the second spring and drives the horizontal plate below to slide upward synchronously. After the sealing block slides upward, its sealing cooperation with the water outlet is released, and the water outlet is fully opened, which has the advantages of preventing external coal slag from entering the interior of the fracturing device and causing blockage of the water outlet.

[0006] (II) Technical Solution

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A fracturing device is included, wherein a movable plate is fixedly connected to both the front and rear surfaces of the fracturing device; an outer expansion plate is movably connected to the lower surface of the movable plate via a shaft; a first bearing seat is fixedly connected to the rear surface of the outer expansion plate; a hollow tube is movably connected to the lower surface of the first bearing seat via a bearing; an air pipe is fixedly connected to the rear surface of the hollow tube; a piston is slidably connected inside the hollow tube; a telescopic rod is provided on the side surface of the piston; a second bearing seat is movably connected to the left end of the telescopic rod via a bearing, and the rear surface of the second bearing seat is fixedly connected to the fracturing device; a first spring is fixedly connected to the rear surface of the outer expansion plate, and the rear end of the first spring is fixedly connected to the fracturing device.

[0008] Preferably, a push rod is fixedly connected to the left end of the expander, and a hose is fixedly connected to the left end of the push rod.

[0009] Preferably, a booster is fixedly connected to the left end of the hose, and a pressure gauge is provided on the upper surface of the booster.

[0010] Preferably, the lower surface of the turbocharger is fixedly connected to the vehicle body, the lower surface of the vehicle body is provided with wheels, and the outer surface of the wheels is provided with anti-slip texture.

[0011] Preferably, a water pump is fixedly connected to the upper surface of the vehicle body, and the output end of the water pump is connected to the booster, and a valve is sleeved on the input end of the water pump.

[0012] Preferably, a water tank is fixedly connected to the upper surface of the vehicle body, and the water tank is connected to the input end of the water pump. An inlet pipe is fixedly connected to the upper surface of the water tank.

[0013] Preferably, the inside of the expansion device is slidably connected to a sealing block, the outer surface of the sealing block is provided with rubber blocks, and the inside of the rubber blocks is provided with rubber rods.

[0014] Preferably, a horizontal plate is fixedly connected to the lower surface of the sealing block, and a second spring is fixedly connected to the upper surface of the horizontal plate, with the top end of the second spring fixedly connected to the inner wall of the expansion joint.

[0015] Preferably, the front and rear surfaces of the expansion device are provided with grooves, and the grooves are fitted and connected to the outer expansion plate. Water outlet holes are provided inside the grooves and on the outer surface of the expansion device, and the water outlet holes are slidably connected to the sealing block.

[0016] A method for directional hydraulic fracturing and pressure relief / permeability enhancement of coal seams includes the following steps:

[0017] S1. Start the vehicle and move the device to the target coal seam working position. Adjust the position of the vehicle so that the fracturing device is aligned with the coal seam area that needs pressure relief and permeability enhancement. Inject sufficient water into the water tank through the water inlet pipe on the upper surface of the water tank. Open the valve at the water pump input end and start the water pump. The water pump delivers the water in the tank to the booster. The booster pressurizes the input water. At the same time, the pressure value is monitored in real time through the air pressure detection gauge on the upper surface of the booster. Adjust the pressure to a suitable range according to the geological conditions of the coal seam and the pressure relief and permeability enhancement requirements.

[0018] S2. The pressurized high-pressure water enters the fracturing device through a hose and pusher rod. Inside the fracturing device, the high-pressure water pushes the piston inside the hollow tube to slide. The piston drives the second bearing seat through the telescopic rod on the side surface. Since the second bearing seat is fixedly connected to the fracturing device, the telescopic rod pushes the piston to move inside the hollow tube. The hollow tube is connected to the outer expansion plate through the first bearing seat. The movement of the piston causes the hollow tube to rotate, which in turn causes the outer expansion plate to rotate and open around the shaft. The first spring on the rear surface of the outer expansion plate is stretched. At this time, the grooves on the front and rear surfaces of the fracturing device are fitted and connected with the outer expansion plate. As the outer expansion plate opens, the water outlet in the groove is gradually exposed.

[0019] S3. The high-pressure water inside the fracturing device simultaneously exerts pressure on the sealing block. The rubber block on the outer surface of the sealing block and the rubber rod inside have a certain elasticity. Under the action of high-pressure water, the sealing block overcomes the elastic force of the second spring and slides downward. The rubber block and the rubber rod deform, so that the sealing block no longer blocks the water outlet. The high-pressure water is sprayed out from the water outlet, forming a directional high-pressure water flow, which hydraulically fractures the coal seam, destroys the structure of the coal seam, forms cracks, and achieves pressure relief and permeability enhancement.

[0020] Compared with the prior art, the present invention provides a directional hydraulic fracturing coal seam depressurization and permeability enhancement device and method, which has the following beneficial effects:

[0021] 1. This invention injects a water-pressure medium into the hollow tube via a gas pipe fixedly connected to it. As the internal pressure of the hollow tube increases, it pushes a piston slidably connected inside the tube to move outward. Since the left end of the telescopic rod is fixedly connected to the fracturing device via a second bearing seat, the outward movement of the piston will reversely drive the entire hollow tube to extend outward. The hollow tube is fixedly connected to the outer expansion plate via a first bearing seat. Therefore, the extension of the hollow tube will drive the outer expansion plate to rotate around the shaft. The movable plate is fixed to the front and rear surfaces of the fracturing device, effectively fixing the rotation fulcrum of the outer expansion plate. Ultimately, the outer expansion plate opens in a preset directional fracturing direction. During the opening process, its outer surface generates directional extrusion force on the coal seam borehole wall, forcing the coal seam to generate initial micro-cracks in that direction. Simultaneously, the rotation of the outer expansion plate stretches the first spring fixedly connected to it, allowing the first spring to store elastic potential energy. The hollow tube and telescopic rod support the outwardly expanding plate, preventing coal seam collapse and causing the outer expansion plate to retract.

[0022] 2. When no high-pressure water is introduced into the device of this invention, the second spring is in a natural support state, with its top end fixed to the inner wall of the rupture chamber and its bottom end fixed to the horizontal plate. The horizontal plate applies an upward supporting force to the sealing block, causing the sealing block to fit tightly against the water outlet position on the inner wall of the rupture chamber, directly sealing the water outlet and preventing premature leakage of the subsequently introduced high-pressure water. The rubber block on the outer surface of the sealing block and the rubber rod embedded inside further enhance the sealing effect. The rubber block uses the elastic deformation of rubber to fill the gap between the sealing block and the inner wall of the rupture chamber and the edge of the water outlet, while the rubber rod reinforces the rubber. The structural strength of the block is ensured to prevent the rubber block from excessively deforming and failing due to subsequent high-pressure extrusion, thus ensuring that a stable high-pressure environment can be established inside the fracturing device. As the internal water pressure gradually increases, the high-pressure water generates an upward thrust on the sealing block. When the upward thrust generated by the water pressure is greater than the upward supporting force of the second spring, the sealing block overcomes the elastic force of the second spring and drives the horizontal plate below to slide upward synchronously. After the sealing block slides upward, its sealing fit with the water outlet is released, and the water outlet is fully opened, which can prevent external coal slag from entering the interior of the fracturing device and causing blockage of the water outlet. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 This is a partial structural diagram of the expansion device of the present invention;

[0025] Figure 3 for Figure 2 Schematic diagram of the structure at point A in the middle;

[0026] Figure 4 This is a schematic diagram of the rear view of the outer expansion plate structure of the present invention;

[0027] Figure 5 This is a schematic diagram of the internal structure of the hollow tube in this invention.

[0028] The components are as follows: 1. Vehicle body; 2. Wheels; 3. Water tank; 4. Inlet pipe; 5. Water pump; 6. Pressure gauge; 7. Intensifier; 8. Expansion device; 9. Push rod; 10. Hose; 11. Piston; 12. Outer expansion plate; 13. Movable plate; 14. Sealing block; 15. Rubber block; 16. Rubber rod; 17. Horizontal plate; 18. Second spring; 19. First spring; 20. First bearing seat; 21. Air pipe; 22. Hollow tube; 23. Telescopic rod; 24. Second bearing seat; 25. Shaft. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1:

[0031] Please see Figure 1-5 A directional hydraulic fracturing coal seam depressurization and permeability enhancement device includes a fracturing device 8. Movable plates 13 are fixedly connected to both the front and rear surfaces of the fracturing device 8. An outer expansion plate 12 is movably connected to the lower surface of the movable plate 13 via a shaft 25. A first bearing seat 20 is fixedly connected to the rear surface of the outer expansion plate 12. A hollow tube 22 is movably connected to the lower surface of the first bearing seat 20 via a bearing. An air pipe 21 is fixedly connected to the rear surface of the hollow tube 22. A piston 11 is slidably connected inside the hollow tube 22. A telescopic rod 23 is provided on the side surface of the piston 11. A second bearing seat 24 is movably connected to the left end of the telescopic rod 23 via a bearing, and the rear surface of the second bearing seat 24 is fixedly connected to the fracturing device 8. A first spring 19 is fixedly connected to the rear surface of the outer expansion plate 12, and the rear end of the first spring 19 is fixedly connected to the fracturing device 8.

[0032] Water pressure medium is injected into the hollow tube 22 through the air pipe 21, which is fixedly connected to the hollow tube 22. After the internal pressure of the hollow tube 22 increases, it pushes the piston 11, which is slidably connected inside the tube, to move. Since the left end of the telescopic rod 23 is fixedly connected to the expander 8 through the second bearing seat 24, the outward movement of the piston 11 will drive the hollow tube 22 to extend outward as a whole. The hollow tube 22 is fixedly connected to the outer expansion plate 12 through the first bearing seat 20. Therefore, the extension action of the hollow tube 22 will drive the outer expansion plate 12 to rotate around the shaft 25, while the movable plate 13 is in the expander. The front and rear surfaces of 8 are equivalent to the rotation fulcrum of the outer expansion plate 12, which ultimately causes the outer expansion plate 12 to open in the preset directional cracking direction. During the opening process of the outer expansion plate 12, its outer surface generates directional extrusion force on the coal seam borehole wall, forcing the coal seam to generate initial micro-cracks in this direction. At the same time, when the outer expansion plate 12 rotates, it will stretch the first spring 19 fixedly connected to it, so that the first spring 19 stores elastic potential energy. The hollow tube 22 and the telescopic rod 23 are used to support the outer expansion plate 12, preventing the coal seam from collapsing and causing the outer expansion plate 12 to be retracted.

[0033] A push rod 9 is fixedly connected to the left end of the expansion rupture device 8. A hose 10 is fixedly connected to the left end of the push rod 9. A booster 7 is fixedly connected to the left end of the hose 10. A pressure gauge 6 is installed on the upper surface of the booster 7. A vehicle body 1 is fixedly connected to the lower surface of the booster 7. A wheel 2 is installed on the lower surface of the vehicle body 1. The outer surface of the wheel 2 is provided with anti-slip texture. A water pump 5 is fixedly connected to the upper surface of the vehicle body 1. The output end of the water pump 5 is connected to the booster 7. A valve is fitted on the input end of the water pump 5. A water tank 3 is fixedly connected to the upper surface of the vehicle body 1. The water tank 3 is connected to the input end of the water pump 5. A water inlet pipe 4 is fixedly connected to the upper surface of the water tank 3.

[0034] Clean water is injected into water tank 3 through inlet pipe 4. Water tank 3 serves as a water storage component, providing a stable water source for the entire device. The input end of water pump 5 is connected to water tank 3, and a valve is installed at the input end. The valve can control the water supply from water tank 3 to water pump 5, facilitating the start and stop of water supply according to work requirements. After water pump 5 starts, it draws in and pressurizes the water in water tank 3. The pressurized water is then delivered to booster 7 through the output end. Booster 7 further pressurizes the water flow to achieve the high pressure conditions required for coal seam fracturing. The pressure gauge 6 on its surface displays the pressure value in the system in real time, allowing operators to monitor and adjust the pressure. The high-pressure water from booster 7 is transmitted to push rod 9 through hose 10, which has a certain degree of flexibility. The device is designed to accommodate the position adjustment of the push rod 9, which transmits high-pressure water to the fracturing device 8 at the right end. The fracturing device 8, as a component that directly acts on the coal seam, expands under the drive of the high-pressure water. The directional force generated by the expansion is used to fracture the coal seam, thereby relieving the pressure on the coal seam. The vehicle body 1 at the bottom of the device and the wheels 2 on the lower surface provide mobility for the entire equipment. The anti-slip texture on the outer surface of the wheels 2 enhances the stability during movement, making it easy to transfer the device to the coal seam to be treated area, ensuring the convenience and flexibility of the fracturing operation. The fracturing device 8 is driven by high-pressure water to perform directional fracturing of the coal seam, releasing the original stress of the coal seam and relieving pressure. At the same time, the generated cracks increase the permeability of the coal seam, achieving the purpose of relieving pressure and increasing permeability of the coal seam.

[0035] A sealing block 14 is slidably connected inside the rupture device 8. Rubber blocks 15 are provided on the outer surface of the sealing block 14. A rubber rod 16 is provided inside the rubber block 15. A horizontal plate 17 is fixedly connected to the lower surface of the sealing block 14. A second spring 18 is fixedly connected to the upper surface of the horizontal plate 17. The top of the second spring 18 is fixedly connected to the inner wall of the rupture device 8. The front and rear surfaces of the rupture device 8 are provided with grooves. The grooves are fitted into the outer expansion plate 12. Water outlet holes are opened inside the grooves and on the outer surface of the rupture device 8. The water outlet holes are slidably connected to the sealing block 14.

[0036] When no high-pressure water is introduced into the device, the second spring 18 is in a naturally supported state, with its top end fixed to the inner wall of the rupture chamber 8 and its bottom end fixed to the horizontal plate 17. The horizontal plate 17 applies an upward supporting force to the sealing block 14, causing the sealing block 14 to fit tightly against the water outlet position of the inner wall of the rupture chamber 8, directly sealing the water outlet and preventing premature leakage of the subsequently introduced high-pressure water. The rubber block 15 on the outer surface of the sealing block 14 and the rubber rod 16 embedded inside further enhance the sealing effect. The rubber block 15 uses the elastic deformation of rubber to fill the gap between the sealing block 14 and the inner wall of the rupture chamber 8 and the edge of the water outlet, while the rubber rod 16 reinforces the rubber. The structural strength of the rubber block 15 is ensured to prevent excessive deformation and failure due to subsequent high-pressure extrusion, thus ensuring a stable high-pressure environment inside the expander 8. As the internal water pressure gradually increases, the high-pressure water exerts an upward thrust on the sealing block 14. When the upward thrust generated by the water pressure is greater than the upward supporting force of the second spring 18, the sealing block 14 overcomes the elastic force of the second spring 18 and drives the lower horizontal plate 17 to slide upward synchronously. After the sealing block 14 slides upward, its sealing cooperation with the water outlet is released, and the water outlet is fully opened, preventing external coal slag from entering the interior of the expander 8 and causing blockage of the water outlet.

[0037] Example 2:

[0038] A method for directional hydraulic fracturing and pressure relief / permeability enhancement of coal seams includes the following steps:

[0039] S1. Start vehicle 1 and move the device to the target coal seam operation position. Adjust the position of vehicle 1 so that the fracturing device 8 is aligned with the coal seam area that needs to be depressurized and permeated. Inject sufficient water into water tank 3 through water inlet pipe 4 on the upper surface of water tank 3. Open the valve at the input end of water pump 5 and start water pump 5. Water pump 5 delivers water from water tank 3 to booster 7. Booster 7 pressurizes the input water. At the same time, the pressure value is monitored in real time through air pressure detection gauge 6 on the upper surface of booster 7. Adjust the pressure to a suitable range according to the geological conditions of the coal seam and the depressurization and permeation requirements.

[0040] S2. The pressurized high-pressure water enters the rupture chamber 8 through the hose 10 and push rod 9. Inside the rupture chamber 8, the high-pressure water pushes the piston 11 inside the hollow tube 22 to slide. The piston 11 drives the second bearing seat 24 through the telescopic rod 23 on the side surface. Since the second bearing seat 24 is fixedly connected to the rupture chamber 8, the telescopic rod 23 pushes the piston 11 to move inside the hollow tube 22. The hollow tube 22 is connected to the outer expansion plate 12 through the first bearing seat 20. The movement of the piston 11 causes the hollow tube 22 to rotate, which in turn causes the outer expansion plate 12 to rotate and open around the shaft 25. The first spring 19 on the rear surface of the outer expansion plate 12 is stretched. At this time, the grooves on the front and rear surfaces of the rupture chamber 8 are fitted and connected with the outer expansion plate 12. As the outer expansion plate 12 opens, the water outlet in the groove is gradually exposed.

[0041] S3. The high-pressure water inside the fracturing device 8 simultaneously exerts pressure on the sealing block 14. The rubber block 15 on the outer surface of the sealing block 14 and the rubber rod 16 inside have a certain elasticity. Under the action of high-pressure water, the sealing block 14 overcomes the elastic force of the second spring 18 and slides downward. The rubber block 15 and the rubber rod 16 deform, so that the sealing block 14 no longer blocks the water outlet. The high-pressure water sprays out from the water outlet, forming a directional high-pressure water flow, which hydraulically fracturing the coal seam, destroying the structure of the coal seam, forming cracks, and achieving pressure relief and permeability enhancement.

[0042] During operation, clean water is injected into the water tank 3 through the inlet pipe 4. The water tank 3 serves as a water storage component, providing a stable water source for the entire device. The input end of the water pump 5 is connected to the water tank 3, and a valve is installed at the input end. The valve controls the flow of water from the water tank 3 to the water pump 5, facilitating the start and stop of water supply according to work requirements. After the water pump 5 starts, it draws in and pressurizes the water in the water tank 3. The pressurized water is then delivered to the booster 7 through the output end. The booster 7 further pressurizes the water flow to achieve the high pressure conditions required for coal seam fracturing. The pressure gauge 6 on its surface displays the pressure value in the system in real time, allowing operators to monitor and adjust the pressure. The high-pressure water from the booster 7 is transmitted to the push rod 9 through the hose 10. The hose 10 has a certain degree of flexibility to adapt to the pushing motion. The position of rod 9 is adjusted, and the push rod 9 transmits high-pressure water to the fracturing device 8 at the right end. As a component that directly acts on the coal seam, the fracturing device 8 expands under the drive of high-pressure water, using the directional force generated by the expansion to fracture the coal seam and relieve pressure. The vehicle body 1 at the bottom of the device and the wheels 2 on the lower surface provide mobility for the entire equipment. The anti-slip texture on the outer surface of the wheels 2 enhances stability during movement, making it easy to transfer the device to the coal seam to be treated area, ensuring the convenience and flexibility of the fracturing operation. Water pressure medium is injected into the hollow tube 22 through the air pipe 21 fixedly connected to the hollow tube 22. After the pressure inside the hollow tube 22 increases, it pushes the piston 11, which is slidably connected inside the tube, to move to the side. Since the left end of the telescopic rod 23 is connected to the fracturing device through the second bearing seat 24, the fracturing device 8... The device 8 is fixedly connected. The outward movement of the piston 11 will cause the hollow tube 22 to extend outward as a whole. The hollow tube 22 is fixedly connected to the outer expansion plate 12 through the first bearing seat 20. Therefore, the extension of the hollow tube 22 will drive the outer expansion plate 12 to rotate around the shaft 25. The movable plate 13 is on the front and rear surfaces of the fracturing device 8, which is equivalent to the rotation fulcrum of the outer expansion plate 12. Finally, the outer expansion plate 12 opens in the preset directional fracturing direction. During the opening process of the outer expansion plate 12, its outer surface generates directional extrusion force on the coal seam borehole wall, forcing the coal seam to generate initial micro-cracks in this direction. At the same time, when the outer expansion plate 12 rotates, it will stretch the first spring 19 fixedly connected to it, so that the first spring 19 stores elastic potential energy. When the device is not supplied with high-pressure water, the second spring 18 is in a natural support state. The top end of the sealing block 14 is fixed to the inner wall of the rupture chamber 8, and the bottom end is fixed to the horizontal plate 17. The horizontal plate 17 applies an upward supporting force to the sealing block 14, making the sealing block 14 fit tightly against the water outlet position of the inner wall of the rupture chamber 8, directly sealing the water outlet and preventing premature leakage of the high-pressure water that is subsequently introduced. The rubber block 15 on the outer surface of the sealing block 14 and the rubber rod 16 embedded inside further enhance the sealing effect. The rubber block 15 uses the elastic deformation of rubber to fill the gap between the sealing block 14 and the inner wall of the rupture chamber 8 and the edge of the water outlet. The rubber rod 16 enhances the structural strength of the rubber block 15, preventing the rubber block 15 from excessively deforming and failing due to subsequent high-pressure compression, ensuring that a stable high-pressure environment can be established inside the rupture chamber 8. As the internal water pressure gradually increases, the high-pressure water generates an upward thrust on the sealing block 14.When the upward thrust generated by the water pressure exceeds the upward supporting force of the second spring 18, the sealing block 14 overcomes the elastic force of the second spring 18, causing the lower horizontal plate 17 to slide upward synchronously. After the sealing block 14 slides upward, its sealing fit with the water outlet is released, and the water outlet is fully opened to fracturing the coal seam.

[0043] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A directional hydraulic fracturing coal seam depressurization and permeability enhancement device, comprising a fracturing device (8), characterized in that: The front and rear surfaces of the expansion device (8) are fixedly connected to movable plates (13). The lower surface of the movable plate (13) is movably connected to an expansion plate (12) via a shaft (25). The rear surface of the expansion plate (12) is fixedly connected to a first bearing seat (20). The lower surface of the first bearing seat (20) is movably connected to a hollow tube (22) via a bearing. The rear surface of the hollow tube (22) is fixedly connected to an air pipe (21). The interior of the hollow tube (22) is slidably connected to a piston (11). The side surface of the piston (11) is provided with a telescopic rod (23). The left end of the telescopic rod (23) is movably connected to a second bearing seat (24) via a bearing. The rear surface of the second bearing seat (24) is fixedly connected to the expansion device (8). The rear surface of the expansion plate (12) is fixedly connected to a first spring (19). The rear end of the first spring (19) is fixedly connected to the expansion device (8).

2. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 1, characterized in that: The left end of the rupture device (8) is fixedly connected to a push rod (9), and the left end of the push rod (9) is fixedly connected to a hose (10).

3. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 2, characterized in that: A booster (7) is fixedly connected to the left end of the hose (10), and a pressure gauge (6) is provided on the upper surface of the booster (7).

4. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 3, characterized in that: The lower surface of the turbocharger (7) is fixedly connected to the vehicle body (1), and the lower surface of the vehicle body (1) is provided with a wheel (2), and the outer surface of the wheel (2) is provided with anti-slip texture.

5. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 4, characterized in that: A water pump (5) is fixedly connected to the upper surface of the vehicle body (1), and the output end of the water pump (5) is connected to the booster (7). A valve is fitted on the input end of the water pump (5).

6. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 4, characterized in that: A water tank (3) is fixedly connected to the upper surface of the vehicle body (1), and the water tank (3) is connected to the input end of the water pump (5). A water inlet pipe (4) is fixedly connected to the upper surface of the water tank (3).

7. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 1, characterized in that: The inside of the expansion device (8) is slidably connected to a sealing block (14), and the outer surface of the sealing block (14) is provided with a rubber block (15), and the inside of the rubber block (15) is provided with a rubber rod (16).

8. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 7, characterized in that: A horizontal plate (17) is fixedly connected to the lower surface of the sealing block (14), and a second spring (18) is fixedly connected to the upper surface of the horizontal plate (17), with the top end of the second spring (18) fixedly connected to the inner wall of the expansion device (8).

9. The directional hydraulic fracturing coal seam depressurization and permeability enhancement device according to claim 1, characterized in that: The front and rear surfaces of the expansion rupture (8) are provided with grooves, and the grooves are fitted and connected to the outer expansion plate (12). The interior of the grooves and the outer surface of the expansion rupture (8) are provided with water outlet holes, and the water outlet holes are slidably connected to the sealing block (14).

10. A method for directional hydraulic fracturing and pressure relief / permeability enhancement of coal seams according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Start the vehicle body (1) and move the device to the target coal seam operation position. Adjust the position of the vehicle body (1) so that the fracturing device (8) is aligned with the coal seam area that needs to be depressurized and permeated. Inject enough water into the water tank (3) through the water inlet pipe (4) on the upper surface of the water tank (3). Open the valve at the input end of the water pump (5) and start the water pump (5). The water pump (5) delivers the water in the water tank (3) to the booster (7). The booster (7) pressurizes the input water. At the same time, the pressure value is monitored in real time through the air pressure detection gauge (6) on the upper surface of the booster (7). Adjust the pressure to a suitable range according to the geological conditions of the coal seam and the depressurization and permeation requirements. S2. The pressurized high-pressure water enters the rupture chamber (8) through the hose (10) and push rod (9). Inside the rupture chamber (8), the high-pressure water pushes the piston (11) inside the hollow tube (22) to slide. The piston (11) drives the second bearing seat (24) through the telescopic rod (23) on the side surface. Since the second bearing seat (24) is fixedly connected to the rupture chamber (8), the telescopic rod (23) pushes the piston (11) to move inside the hollow tube (22). The hollow tube (22) is connected to the outer expansion plate (12) through the first bearing seat (20). The movement of the piston (11) drives the hollow tube (22) to rotate, which in turn causes the outer expansion plate (12) to rotate and open around the shaft (25). The first spring (19) on the rear surface of the outer expansion plate (12) is stretched. At this time, the grooves on the front and rear surfaces of the expansion device (8) are fitted and connected with the outer expansion plate (12). As the outer expansion plate (12) opens, the water outlet in the groove is gradually exposed. S3. The high-pressure water inside the expansion fracturing device (8) simultaneously exerts pressure on the sealing block (14). The rubber block (15) on the outer surface of the sealing block (14) and the rubber rod (16) inside have a certain elasticity. Under the action of the high-pressure water, the sealing block (14) overcomes the elastic force of the second spring (18) and slides downward. The rubber block (15) and the rubber rod (16) deform, so that the sealing block (14) no longer blocks the water outlet. The high-pressure water sprays out from the water outlet, forming a directional high-pressure water flow, which hydraulically fractures the coal seam, destroys the structure of the coal seam, forms cracks, and achieves pressure relief and permeability enhancement.

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