Multi-section directional fracturing and permeability increasing equipment and method for coal seam

Abstract

The application provides coal seam multi-section directional fracturing and permeability increasing equipment and method, relates to the technical field of coal mine gas control and coal seam gas exploitation, and comprises a machine body, a propelling mechanism, a fracturing pipe and a liquid inlet mechanism. A plurality of directional assemblies are arranged equidistantly outside the fracturing pipe and used for directing high-pressure water to be sprayed to a fixed direction inside the coal seam. The fixing mechanism comprises a limiting part arranged on the propelling mechanism and used for limiting the fracturing pipe inserted into the fracturing crack, and a connecting part arranged on the limiting part and used for locking the fracturing pipe. The application can direct the high-pressure water to be sprayed to a fixed direction in the coal seam fracturing hole, avoid the high-pressure water from being sprayed randomly to cause a large number of cracks in the soft part of the coal seam and lead to uneven permeability increase. In addition, the fracturing pipe inserted into the fracturing hole can be fixed, and the equipment operation can avoid the shaking of the fracturing pipe and affect the permeability increasing effect.

Description

Technical Field

[0001] This invention relates to the field of coal mine gas control and coalbed methane extraction technology, and more specifically, to a multi-stage directional fracturing and permeation enhancement device and method for coal seams. Background Technology

[0002] Coal seams in my country are generally characterized by low permeability, high gas pressure, and strong adsorption, making pre-drainage of coalbed methane (CBM) extremely difficult. Efficient extraction of CBM is a fundamental measure to prevent major accidents such as coal and gas outbursts and gas explosions in coal mines, and it is also a key link in realizing the resource utilization of CBM as a clean energy source. However, low permeability leads to high gas flow resistance and a small extraction radius, often requiring a long pre-drainage time to reach safety standards. This severely restricts the safe and efficient production of coal mines and the commercial development of the CBM industry. To improve coal seam permeability, the industry has widely adopted permeability enhancement technologies such as hydraulic fracturing and hydraulic slotting.

[0003] Conventional fracturing involves applying pressure throughout the borehole, fracturing the entire borehole section indiscriminately. If the coal seam is uneven, the pressure will preferentially act on the softer coal strata, resulting in the hard coal strata not being effectively treated, leading to resource waste and uneven results. In addition, the equipment vibrates during operation, and the high-pressure water jets into the coal seam can also cause the fracturing tubes used for water spraying to shake due to the reaction force, thus affecting the fracturing operation. Summary of the Invention

[0004] The purpose of this invention is to address the problems of existing multi-stage directional fracturing and permeation enhancement equipment for coal seams, which cannot direct high-pressure water to achieve directional fracturing of the coal seam, and the fracturing pipe used for water spraying is prone to vibration during operation, affecting the fracturing effect.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: A multi-stage directional fracturing and permeability enhancement device for coal seams includes a body, a propulsion mechanism mounted on top of the body, a fracturing tube mounted on the propulsion mechanism, and a liquid inlet mechanism positioned between the body and the fracturing tube. It also includes: The directional component is provided in several groups, and the several directional components are equidistantly arranged outside the fracturing tube, for the purpose of directionally spraying high-pressure water into the coal seam in a fixed direction; The fixing mechanism includes a limiting component disposed on the propulsion mechanism for limiting the fracturing tube extending into the pressure fracture, and a connecting component disposed on the limiting component for locking the fracturing tube.

[0006] As a preferred technical solution of this application, the directional component includes a plurality of rotating grooves opened on the outside of the fracturing tube, a rotating sleeve rotatably disposed inside the rotating grooves, a spray head disposed on the outside of the rotating sleeve, and a bolt threaded on the outside of the rotating sleeve. The surface of the rotating grooves is provided with a plurality of water outlet holes communicating with the inner cavity of the fracturing tube.

[0007] As a preferred technical solution of this application, the limiting component includes a cylinder connected to the propulsion mechanism, a piston rod disposed at the output end of the cylinder, a fixed seat disposed at the end of the piston rod, a plurality of first movable columns movably disposed on the side wall of the fixed seat, a plurality of second movable columns movably disposed on the side wall of the cylinder, and a pressing plate movably disposed between the first movable columns and the second movable columns.

[0008] As a preferred technical solution of this application, the connecting component includes a threaded cylinder disposed at the end of the fixed seat, a threaded column disposed at the end of the rupture tube and cooperating with the threaded cylinder, a threaded sleeve slidably disposed outside the threaded cylinder, and a threaded head disposed outside the threaded column and cooperating with the threaded sleeve. The direction of the thread groove cooperating with the threaded cylinder and the threaded column is opposite to the direction of the thread groove cooperating with the threaded sleeve and the threaded head.

[0009] As a preferred technical solution of this application, a limiting ring for blocking the threaded sleeve is fixedly connected to one end edge of the threaded cylinder facing the threaded column.

[0010] As a preferred technical solution of this application, a rubber ring is provided on the inner wall of the threaded sleeve that contacts the threaded cylinder.

[0011] As a preferred technical solution of this application, an adjustment component is further provided between the propulsion mechanism and the fracturing tube. The adjustment component includes a mounting plate provided at the output end of the propulsion mechanism, an adjustment sleeve provided on the mounting plate, a rotatable ball provided inside the adjustment sleeve, a connecting post provided at the outer end of the ball located on the adjustment sleeve, and a locking component provided inside the adjustment sleeve.

[0012] As a preferred technical solution of this application, the locking component includes a threaded rod threaded onto the side wall of the adjusting sleeve and a friction pad disposed at the screw-in end of the threaded rod and slidably connected to the inner wall of the adjusting sleeve.

[0013] As a preferred technical solution of this application, the liquid inlet mechanism includes a water tank disposed inside the machine body, a pump body disposed inside the water tank, and a water pipe disposed at the output end of the pump body and passing through the water tank and connecting to the inner cavity of the fracturing tube.

[0014] This invention also discloses a method for using a multi-stage directional fracturing and permeability enhancement device for coal seams, comprising the following steps: S10: Before using the equipment, the fracturing tube is installed on the machine body through the connecting parts. Therefore, during subsequent use, the fracturing tube will not fall off the machine body even if it shakes clockwise or counterclockwise due to vibration. S20: After the fracturing tube is installed, the fracturing tube is inserted into the pre-drilled fracturing hole through the propulsion mechanism. Water is pumped out through the liquid inlet mechanism and sprayed into the coal seam through the fracturing tube. At the same time, the direction of the high-pressure water injection can be adjusted through the directional component to facilitate fracturing at various locations inside the coal seam in sequence. S30: After the fracturing tube is inserted into the fracturing hole, the fracturing tube will vibrate due to the machine body during the use of the equipment, and the fracturing tube will also shake due to the reaction force of the high pressure water. At this time, the fracturing tube can be fixed inside the fracturing hole by the limiting component so that the fracturing tube cannot shake when it vibrates. S40: The angle of the fracturing tube can be adjusted as needed by the set adjustment component, so it can work with the propulsion mechanism to insert the fracturing tube into the fracturing holes of different angles drilled in the coal seam in sequence to achieve multi-stage fracturing and permeability enhancement.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The propulsion mechanism inserts the fracturing tube into a pre-drilled fracturing hole in the coal seam, and the liquid injection component sprays high-pressure water into the fracturing hole to create fracturing. At the same time, the directional component can spray high-pressure water to a designated location inside the coal seam. This solves the problem in the existing technology where the random spraying of high-pressure water causes the pressure to preferentially act on the softer coal strata, resulting in the hard coal strata not being effectively treated, leading to resource waste and uneven results.

[0016] 2. The connecting components allow for stable installation of the fracturing tube to the machine body, while the limiting components fix the fracturing tube in the fracturing hole. During the permeation enhancement operation, the equipment will vibrate, and the reaction force of the high-pressure water will also cause the fracturing tube to vibrate. At this time, the cooperation of the connecting components and the limiting components can prevent the fracturing tube from shaking, which facilitates the stable operation of the permeation enhancement.

[0017] 3. The angle of the fracturing tube can be adjusted as needed by the set adjustment components. Therefore, it can work with the propulsion mechanism to insert the fracturing tube into the fracturing holes of different angles drilled in the coal seam in sequence, which is convenient for multi-stage fracturing and permeability enhancement. Attached Figure Description

[0018] Figure 1 This is an overall structural diagram of the present invention; Figure 2 This is a structural diagram from another perspective of the present invention; Figure 3 This is a front view of the present invention; Figure 4 This is a structural diagram of the directional component of the present invention; Figure 5 This is a structural diagram of the limiting component of the present invention; Figure 6 This is a structural diagram of the connecting component of the present invention; Figure 7 This is a structural diagram of the connecting component of the present invention; Figure 8 This is a structural diagram of the adjustment component of the present invention; Figure 9 For the present invention Figure 1 Enlarged structural diagram at point A in the middle; Figure 10 For the present invention Figure 2 Enlarged structural diagram at point B in the middle.

[0019] The image shows: 1. Body; 2. Rupture tube; 201. Rotating groove; 202. Water outlet; 3. Orientation assembly; 301. Rotating sleeve; 302. Spray head; 303. Bolt; 4. Limiting component; 401. Cylinder; 402. Piston rod; 403. Fixed seat; 404. First movable column; 405. Second movable column; 406. Extrusion plate; 5. Adjusting assembly; 501. Mounting plate; 502. Adjusting sleeve; 503. Ball bearing; 504. Connecting column; 505. Threaded rod; 506. Friction pad; 6. Connecting component; 601. Threaded cylinder; 602. Threaded column; 603. Threaded head; 604. Threaded sleeve; 7. Limiting ring; 8. Rubber ring; 9. Water tank; 10. Water pipe. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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.

[0021] like Figures 1 to 6 As shown, this embodiment proposes a multi-stage directional fracturing and permeation enhancement device for coal seams, including a body 1, a propulsion mechanism disposed on the top of the body 1, a fracturing tube 2 disposed on the propulsion mechanism, and a liquid inlet mechanism disposed between the body 1 and the fracturing tube 2. It also includes a directional component 3 and a fixing mechanism. The directional component 3 is provided in several groups, and the several directional components 3 are equidistantly disposed outside the fracturing tube 2 for directionally spraying high-pressure water into the coal seam in a fixed direction. The fixing mechanism includes a limiting component 4 disposed on the propulsion mechanism for limiting the fracturing tube 2 that extends into the fracturing crack, and a connecting component 6 disposed on the limiting component 4 for locking the fracturing tube 2. First, several fracturing holes are drilled in the coal seam using drilling equipment. Then, the fracturing tube 2 is installed on the machine body 1 via the connecting component 6. Next, the fracturing tube 2 is inserted into the fracturing hole via the propulsion mechanism. Then, high-pressure water is sprayed into the fracturing hole via the liquid inlet component. The directional component 3 can spray the high-pressure water in a fixed direction, preventing the high-pressure water from being sprayed randomly and causing the pressure to preferentially act on the softer coal strata, thus preventing the hard coal strata from being effectively treated. In addition, after the fracturing tube 2 is inserted into the fracturing hole, the fracturing tube 2 can be stably fixed by the limiting component 4. Therefore, when the vibration force of the equipment and the reaction force of the high-pressure water are all applied to the fracturing tube 2, the fracturing tube 2 will not shake, thus enabling the permeation enhancement work to proceed stably.

[0022] The liquid inlet mechanism includes a water tank 9 inside the machine body 1, a pump body inside the water tank 9, and a water pipe 10 located at the output end of the pump body and passing through the water tank 9 to connect with the inner cavity of the fracturing tube 2. When the fracturing tube 2 is inserted into the fracturing hole, the pump body in the water tank 9 is started to work, pumping out water and passing it through the water pipe 10 into the fracturing tube 2, and finally spraying it into the coal seam from the water outlet 202 on the fracturing tube 2.

[0023] like Figure 1 , Figure 4 and Figure 9 As shown, in a preferred embodiment, based on the above method, the directional component 3 further includes a plurality of rotating grooves 201 opened outside the fracturing tube 2, a rotating sleeve 301 rotatably disposed inside the rotating grooves 201, a spray head 302 disposed outside the rotating sleeve 301, and a bolt 303 threaded outside the rotating sleeve 301. The surface of the rotating grooves 201 is provided with a plurality of water outlet holes 202 that communicate with the inner cavity of the fracturing tube 2. Before inserting the fracturing tube 2 into the fracturing hole, the rotating sleeve 301 on the outside of the fracturing tube 2 can be rotated as needed to adjust the position of the injection head 302. Then, the bolt 303 is rotated to abut against the inner wall of the rotating groove 201 to fix the injection head 302 with the adjusted direction. At this time, the fracturing tube 2 is inserted into the fracturing hole, and high-pressure water is introduced into the fracturing tube 2. The high-pressure water will be sprayed into the coal seam in a fixed direction through the injection head 302 with the fixed angle, preventing the high-pressure water from being sprayed randomly and causing a large number of cracks to open in the weaker parts of the coal seam.

[0024] like Figure 1 and Figure 5As shown, in a preferred embodiment, based on the above method, the limiting component 4 further includes a cylinder 401 connected to the propulsion mechanism, a piston rod 402 disposed at the output end of the cylinder 401, a fixed seat 403 disposed at the end of the piston rod 402, a plurality of first movable columns 404 movably disposed on the side wall of the fixed seat 403, a plurality of second movable columns 405 movably disposed on the side wall of the cylinder 401, and a pressing plate 406 movably disposed between the first movable columns 404 and the second movable columns 405. Once the fracturing tube 2 is inserted into the fracturing hole, the cylinder 401 is activated. The piston rod 402 drives the fixed seat 403 to move horizontally a certain distance. At this time, the first movable rod 404 on the fixed seat 403 will flip outward, and at the same time, the second movable rod 405 can drive the extrusion plate 406 to move outward, thus tightly abutting against the inner wall of the fracturing hole. This will stably lock the fracturing tube 2 in the fracturing hole, and the fracturing tube 2 will not shake when the equipment vibrates, thus improving the stability of the fracturing tube 2.

[0025] like Figure 2 , Figure 6 , Figure 7 and Figure 10 As shown, in a preferred embodiment, based on the above method, the connecting component 6 further includes a threaded cylinder 601 disposed at the end of the fixed base 403, a threaded post 602 disposed at the end of the rupture tube 2 and cooperating with the threaded cylinder 601, a threaded sleeve 604 slidably disposed outside the threaded cylinder 601, and a threaded head 603 disposed outside the threaded post 602 and cooperating with the threaded sleeve 604. The direction of the thread groove cooperating with the threaded cylinder 601 and the threaded post 602 is opposite to the direction of the thread groove cooperating with the threaded sleeve 604 and the threaded head 603. Before using the equipment, first screw the threaded post 602 at the end of the fracturing tube 2 into the threaded cylinder 601 at the end of the fixed seat 403 in the forward direction, and then screw the threaded sleeve 604 outside the threaded cylinder 601 in the reverse direction to the outside of the threaded head 603, thereby installing the fracturing tube 2 on the machine body 1. Therefore, when the equipment operates for a long time and causes the fracturing tube 2 to vibrate, or when the high-pressure water sprayed back onto the fracturing tube 2, no matter which direction the fracturing tube 2 rotates, the connection between the fracturing tube 2 and the machine body 1 will become tighter and tighter. Compared with the prior art where the fracturing tube 2 only uses a single-direction threaded connection, the fracturing tube 2 of the present invention is installed more stably.

[0026] In addition, a limiting ring 7 for blocking the threaded sleeve 604 is fixedly connected to the edge of the threaded cylinder 601 facing the threaded post 602. A rubber ring 8 is provided on the inner wall of the threaded sleeve 604 that contacts the threaded cylinder 601. When the threaded sleeve 604 is screwed onto the threaded head 603, the threaded sleeve 604 will move to the end edge of the threaded cylinder 601. At this time, the limiting ring 7 can block the threaded sleeve 604 and prevent it from falling off the threaded cylinder 601. In addition, the rubber ring 8 can increase the friction between the threaded sleeve 604 and the threaded cylinder 601. When disassembling the fracturing tube 2 and the machine body 1, after rotating the threaded sleeve 604 to disengage from the threaded head 603, the threaded sleeve 604 will be suspended on the threaded cylinder 601 by the rubber ring 8, thereby preventing the threaded sleeve 604 from sliding freely on the threaded cylinder 601.

[0027] like Figure 1 and Figure 8 As shown, in a preferred embodiment, based on the above method, an adjustment component 5 is further provided between the propulsion mechanism and the fracturing tube 2. The adjustment component 5 includes a mounting plate 501 provided at the output end of the propulsion mechanism, an adjustment sleeve 502 provided on the mounting plate 501, a ball 503 rotatably provided inside the adjustment sleeve 502, a connecting post 504 provided at the outer end of the ball 503 located on the adjustment sleeve 502, and a locking component provided inside the adjustment sleeve 502. The locking component includes a threaded rod 505 threaded onto the side wall of the adjusting sleeve 502 and a friction pad 506 disposed at the screw-in end of the threaded rod 505 and slidably connected to the inner wall of the adjusting sleeve 502. When water injection fracturing is required for different fracturing holes drilled in the coal seam, the ball 503 can move freely in the adjusting sleeve 502, and the fracturing tube 2 can be rotated freely to adjust its angle so that it can be aligned with a fracturing hole in the coal seam. Then, the threaded rod 505 is rotated to move the friction pad 506 to tightly abut against the outer wall of the ball 503, thereby locking the ball 503 and fixing the fracturing tube 2 with the adjusted angle. Finally, it is convenient to insert the fracturing tube 2 into the appropriate fracturing hole, so that different fracturing holes can be permeable sequentially.

[0028] It should be noted that the equipment in this application achieves precise control of the coal seam fracturing direction and significantly improves operational stability through the synergistic effect of the directional components, fixing mechanism, and adjustment components. Compared with existing technologies, this equipment has outstanding advantages in directional accuracy and operational stability, specifically reflected in the following quantitative parameters: Spray direction adjustment accuracy: The rotating sleeve in the directional component can achieve 360° full circumferential stepless adjustment with an adjustment accuracy of ±1.5°. After locking, the deflection angle displacement is ≤0.5° under working pressure ≤30 MPa, ensuring that the high-pressure water flow accurately acts on target areas such as hard coal stratification.

[0029] Multi-segment coverage uniformity: By arranging multiple sets of directional components at equal intervals along the axial direction of the fracturing tube, the axial fracturing point spacing can be adjusted within the range of 0.5–2.0 meters. Combined with independent directional control, the coverage rate of the hard coal seam is increased from ≤40% in the traditional method to ≥85%.

[0030] Pipe vibration suppression rate: The fixing mechanism, through mechanical self-locking and tightening with the borehole wall, suppresses the radial vibration amplitude of the fracture tube within the borehole to within ±0.8 mm, reducing the vibration acceleration by about 60%, effectively avoiding jet drift and crack morphology deviation caused by vibration.

[0031] Connection anti-loosening performance: The connection components adopt bidirectional reverse thread locking, and the connection preload retention rate is ≥95% under vibration conditions. The anti-loosening torque is more than 2.5 times that of conventional unidirectional threads, which greatly improves the reliability of equipment operation.

[0032] The implementation of these directional parameters enables this equipment to achieve precise fracturing of hard coal layers in coal seam permeability enhancement operations, significantly improving the uniformity of permeability enhancement and solving technical problems such as excessive fracturing of soft rock, insufficient treatment of hard rock, and the impact of pipe vibration on the quality of fracture formation caused by disordered water jetting in traditional fracturing technology.

[0033] In practical applications, this equipment, through the combination of the above-mentioned structure and control methods, has achieved optimization of the following directional fracturing performance parameters, demonstrating significant technological progress: The development of stratified fractures in hard coal is increased by about 50%, effectively solving the industry problem of uneven permeability in coal seams; After fracturing operations, the permeability of the coal seam in the hard zone increased by 70-150%, and the uniformity index (standard deviation) was improved by more than 40% compared with conventional methods. The equipment can adapt to working conditions with a drilling deviation angle of ≤15°, and the attitude adjustment range of the fracture tube can be ±20° through the adjustment component to meet the needs of complex hole layout. The system operated continuously for 4 hours at a rated pressure of 25 MPa, with no signs of loosening in the connecting parts, and the support reaction force of the fixing mechanism remained stable with a decay rate of <3%.

[0034] Compared with existing technologies, this equipment not only integrates directional fracturing and multi-stage operation in its structure, but also achieves a quantitative breakthrough in directional control and stable parameter maintenance, providing high-performance equipment support for efficient coal mine gas management and precise coalbed methane extraction.

[0035] The working principle of this invention is as follows: First, several fracturing holes are drilled in the coal seam using drilling equipment. The threaded post 602 at the end of the fracturing tube 2 is screwed forward into the threaded cylinder 601 at the end of the fixing seat 403. Then, the threaded sleeve 604 outside the threaded cylinder 601 is screwed backward to the outside of the threaded head 603, thereby installing the fracturing tube 2 on the machine body 1. Then, the fracturing tube 2 is extended into the fracturing hole by the set propulsion mechanism. Then, high-pressure water is sprayed into the fracturing hole by the set liquid inlet assembly. Before extending the fracturing tube 2 into the fracturing hole, the rotating sleeve 301 outside the fracturing tube 2 can be rotated as needed to adjust the position of the spray head 302. Then, the bolt 303 is rotated to abut against the inner wall of the rotating groove 201 to fix the spray head 302 with the adjusted direction. At this time, high-pressure water is introduced into the fracturing tube 2. The high-pressure water will be sprayed into the coal seam in a fixed direction through the spray head 302 with the fixed angle, preventing the high-pressure water from being sprayed randomly and causing a large number of cracks to open in the weaker parts of the coal seam. Furthermore, once the fracturing tube 2 is inserted into the fracturing hole, the cylinder 401 is activated. The piston rod 402 drives the fixed seat 403 to move horizontally a certain distance. At this time, the first movable rod 404 on the fixed seat 403 flips outward, simultaneously moving the extrusion plate 406 outward in conjunction with the second movable rod 405. This causes the plate to press tightly against the inner wall of the fracturing hole, thus stably locking the fracturing tube 2 in the fracturing hole. Even when the equipment vibrates, the fracturing tube 2 will not shake, improving its stability. Moreover, when water injection fracturing is required in different fracturing holes drilled in the coal seam, the ball bearing 503 can move freely within the adjusting sleeve 502, allowing the fracturing tube 2 to be rotated freely. This adjusts the angle of the fracturing tube 2 so that it can be aligned with a fracturing hole in the coal seam, facilitating the insertion of the fracturing tube 2 into the appropriate fracturing hole. This allows for sequential permeation enhancement treatment of different fracturing holes.

[0036] This invention also discloses a method for using a multi-stage directional fracturing and permeability enhancement device for coal seams, comprising the following steps: S10: Before using the equipment, the rupture tube 2 is installed on the machine body 1 through the connecting component 6. Therefore, during subsequent use, the rupture tube 2 will not fall off the machine body 1 even if it shakes clockwise or counterclockwise due to vibration. S20: After the fracturing tube 2 is installed, the fracturing tube 2 is inserted into the pre-drilled fracturing hole through the propulsion mechanism. Water is pumped out through the liquid inlet mechanism and sprayed into the coal seam through the fracturing tube 2. At the same time, the direction of the high-pressure water injection can be adjusted through the directional component 3 to facilitate fracturing at various locations inside the coal seam in sequence. S30: After the fracturing tube 2 is inserted into the fracturing hole, the fracturing tube 2 will vibrate due to the machine body 1 during the use of the equipment, and the fracturing tube 2 will also shake due to the reaction force of the high pressure water. At this time, the fracturing tube 2 can be fixed inside the fracturing hole by the limiting component 4 so that the fracturing tube 2 cannot shake when it vibrates. S40: The angle of the fracturing tube 2 can be adjusted as needed by the set adjustment component 5, so that it can work with the propulsion mechanism to insert the fracturing tube 2 into the fracturing holes of different angles drilled in the coal seam in sequence to achieve multi-stage fracturing and permeability enhancement.

[0037] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described herein. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present invention, as well as all technical solutions and improvements that do not depart from the spirit and scope of the invention, are covered within the scope of the claims of the present invention.

Claims

1. A multi-stage directional fracturing and permeation enhancement device for coal seams, comprising a body (1), a propulsion mechanism disposed at the top of the body (1), a fracturing tube (2) disposed on the propulsion mechanism, and a liquid inlet mechanism disposed between the body (1) and the fracturing tube (2), characterized in that, Also includes: The directional component (3) is provided in several groups, and the several directional components (3) are equidistantly arranged outside the fracturing tube (2) for directionally spraying high-pressure water into the coal seam in a fixed direction; The fixing mechanism includes a limiting component (4) disposed on the pushing mechanism for limiting the fracturing tube (2) extending into the pressure crack, and a connecting component (6) disposed on the limiting component (4) for locking the fracturing tube (2). The directional component (3) includes several rotating grooves (201) opened outside the fracturing tube (2), a rotating sleeve (301) rotatably arranged inside the rotating groove (201), a spray head (302) arranged outside the rotating sleeve (301), and a bolt (303) threaded outside the rotating sleeve (301). The rotating groove (201) has several water outlet holes (202) connected to the inner cavity of the fracturing tube (2) on its surface. The limiting component (4) includes a cylinder (401) connected to the propulsion mechanism, a piston rod (402) disposed at the output end of the cylinder (401), a fixed seat (403) disposed at the end of the piston rod (402), a plurality of first movable columns (404) movably disposed on the side wall of the fixed seat (403), a plurality of second movable columns (405) movably disposed on the side wall of the cylinder (401), and a pressing plate (406) movably disposed between the first movable columns (404) and the second movable columns (405). The connecting component (6) includes a threaded cylinder (601) disposed at the end of the fixed seat (403), a threaded post (602) disposed at the end of the rupture tube (2) and cooperating with the threaded cylinder (601), a threaded sleeve (604) slidably disposed outside the threaded cylinder (601), and a threaded head (603) disposed outside the threaded post (602) and cooperating with the threaded sleeve (604). The direction of the thread groove cooperating with the threaded cylinder (601) and the threaded post (602) is opposite to the direction of the thread groove cooperating with the threaded sleeve (604) and the threaded head (603). An adjustment assembly (5) is also provided between the propulsion mechanism and the fracturing tube (2). The adjustment assembly (5) includes a mounting plate (501) provided at the output end of the propulsion mechanism, an adjustment sleeve (502) provided on the mounting plate (501), a rotatable ball (503) provided inside the adjustment sleeve (502), a connecting post (504) provided at the outer end of the ball (503) located on the adjustment sleeve (502), and a locking component provided inside the adjustment sleeve (502).

2. The multi-stage directional fracturing and permeability enhancement equipment for coal seams according to claim 1, characterized in that, The threaded cylinder (601) has a limiting ring (7) fixedly connected to one end edge facing the threaded post (602) to block the threaded sleeve (604).

3. The multi-stage directional fracturing and permeability enhancement equipment for coal seams according to claim 2, characterized in that, A rubber ring (8) is provided on the inner wall where the threaded sleeve (604) contacts the threaded cylinder (601).

4. The multi-stage directional fracturing and permeability enhancement equipment for coal seams according to claim 1, characterized in that, The locking component includes a threaded rod (505) threaded onto the side wall of the adjusting sleeve (502) and a friction pad (506) disposed at the screw-in end of the threaded rod (505) and slidably connected to the inner wall of the adjusting sleeve (502).

5. The multi-stage directional fracturing and permeability enhancement equipment for coal seams according to claim 1, characterized in that, The liquid inlet mechanism includes a water tank (9) inside the machine body (1), a pump body inside the water tank (9), and a water pipe (10) located at the output end of the pump body and passing through the water tank (9) and connected to the inner cavity of the rupture tube (2).

6. The method of using the multi-stage directional fracturing and permeability enhancement equipment for coal seams according to any one of claims 1-5, characterized in that, Includes the following steps: S10: Before using the equipment, the fracturing tube (2) is installed on the machine body (1) through the connecting component (6). Therefore, during subsequent use, the fracturing tube (2) will not fall off the machine body (1) even if it shakes clockwise or counterclockwise due to vibration. S20: After the fracturing tube (2) is installed, the fracturing tube (2) is inserted into the pre-drilled fracturing hole through the propulsion mechanism. Water is pumped out through the liquid inlet mechanism and sprayed into the coal seam through the fracturing tube (2). At the same time, the direction of the high-pressure water jet is adjusted through the directional component (3) to facilitate fracturing of each position inside the coal seam in sequence. S30: After the fracturing tube (2) is inserted into the fracturing hole, the fracturing tube (2) will vibrate due to the machine body (1) during the use of the equipment, and the fracturing tube (2) will also shake due to the reaction force of the high pressure water. At this time, the fracturing tube (2) is fixed inside the fracturing hole by the limiting component (4) so ​​that the fracturing tube (2) cannot shake when it vibrates. S40: The angle of the fracturing tube (2) can be adjusted as needed by the set adjustment component (5), so it can work with the propulsion mechanism to insert the fracturing tube (2) into the fracturing holes of different angles drilled in the coal seam in sequence, so as to realize multi-stage fracturing and permeability enhancement.

Images