A grouting device and grouting method for front coal seam roof water plugging

Abstract

The present application relates to the technical field of coal mining, and particularly relates to a grouting device and grouting method for water plugging of a front coal seam roof. The grouting device for water plugging of the front coal seam roof comprises a cart, a stirring cylinder is arranged on the top of the cart, a pump body is communicated with the bottom of the stirring cylinder through a pipeline, an output end of the pump body is communicated with a grout conveying pipe, the other end of the grout conveying pipe is communicated with a cavity, a grouting pipe is rotatably arranged in the cavity, an outer drill bit for drilling and grouting is arranged on the end of the grouting pipe, and a first spiral blade for discharging waste slag generated during drilling is arranged on the outer wall of the grouting pipe. The grouting device and grouting method for water plugging of the front coal seam roof integrate the functions of drilling and grouting in the same device, the drill bit at the end of the grouting pipe is driven to rotate by a motor to realize drilling, the first spiral blade on the outer wall of the grouting pipe synchronously completes slag discharge, and after drilling is completed, the device does not need to be replaced and grouting can be directly performed, thereby improving construction efficiency.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and in particular to a grouting device and grouting method for plugging water in the roof of the front coal seam. Background Technology

[0002] During coal mining, water hazards in the roof of the coal seam seriously threaten the safety of mine production and mining efficiency. Grouting and water plugging are widely used as an effective prevention and control method. However, existing coal seam roof grouting equipment and processes have significant defects and are difficult to meet the engineering needs under complex geological conditions.

[0003] Current grouting operations generally adopt a step-by-step construction mode, which requires drilling with independent drilling equipment first. After the borehole reaches the predetermined depth, the equipment is replaced and the grouting pipe is installed for grouting. This step-by-step operation method has shortcomings. First, the equipment replacement process is cumbersome, requiring a lot of time for disassembling the drilling equipment and installing and debugging the grouting equipment, which significantly reduces construction efficiency and prolongs the project cycle. In addition, existing grouting equipment faces the problem of grout sedimentation during relocation. After completing a grouting operation, the equipment needs to be moved to the next grouting point. During this period, the grout remaining in the grouting pipe is prone to sedimentation and stratification due to the long settling time. The uneven concentration distribution of the sedimented grout affects its fluidity and injectability, making it difficult to ensure uniform diffusion and effective filling of the grout during subsequent grouting, thus reducing the water-blocking effect. At the same time, the sedimented grout may also clog the grouting pipeline and equipment components, increasing equipment maintenance costs and failure risks.

[0004] Therefore, it is necessary to provide a new grouting device and grouting method for plugging water in the roof of the coal seam to solve the above-mentioned technical problems. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the present invention provides a grouting device and grouting method for plugging water in the roof of a coal seam.

[0006] The grouting device for plugging water in the roof of a coal seam provided by the present invention includes: a trolley, a mixing cylinder placed on the top of the trolley, a pump body connected to the bottom of the mixing cylinder through a pipe, a grout delivery pipe connected to the output end of the pump body, a cavity connected to the other end of the grout delivery pipe, a grouting pipe rotatably installed inside the cavity, an external drill bit for drilling grouting installed at the end of the grouting pipe, a first spiral blade for discharging waste generated during drilling installed on the outer wall of the grouting pipe, fan-shaped plates equidistantly arranged on the outer wall of the grouting pipe near the external drill bit, a driving assembly installed between the fan-shaped plates and the cavity, the driving assembly driving the fan-shaped plates to expand outward and press against the inner wall of the borehole to prevent grout from flowing out of the borehole during grouting, and a turbulence emulator installed inside the grouting pipe near the cavity, the turbulence emulator being used to uniformly mix the grout remaining in the grout delivery pipe to prevent it from settling.

[0007] Preferably, the drive assembly includes: an extrusion rod, an extrusion column, a tension spring, a connecting rod, and a disc. An installation cylinder is fixedly connected to the outer wall of the grouting pipe near the outer drill bit. The other end of the installation cylinder is fixedly connected to the outer drill bit. Equally spaced fan-shaped grooves are provided on the outer side of the installation cylinder. Each fan-shaped plate is placed in a corresponding fan-shaped groove. An extrusion rod penetrating the inner wall of the grouting pipe is fixedly connected to the inner wall of each fan-shaped plate. A tension spring is fitted onto the outer wall of each extrusion rod. One end of each tension spring is fixedly connected to the inner wall of a corresponding fan-shaped plate, and the other end is fixedly connected to the grouting pipe. An extrusion column is slidably connected to the inner wall of the grouting pipe near the fan-shaped plate. A connecting rod is symmetrically fixedly connected to the end of the extrusion column away from the outer drill bit. A disc is fixedly connected to the other end of the connecting rod. The disc is placed inside the cavity and tightly fitted against its inner wall.

[0008] Preferably, the grouting pipe has grooves at equal intervals near the disc for grout flow. The grooves are located inside the cavity, and the disc has connecting holes at equal intervals inside. The grooved section of the grouting pipe is slidably connected to the inner wall of the connecting hole of the disc.

[0009] Preferably, a drive box is provided at the end of the grouting pipe away from the external drill bit. A motor is fixedly connected inside the drive box. The end of the grouting pipe extends into the drive box and is fixedly connected to the output end of the motor. The end of the cavity is fixedly connected to the side wall of the drive box through a connecting bracket.

[0010] Preferably, handles are fixedly connected to both sides of the drive box, and a pull rod is slidably connected to one side of each handle. Connecting rods are symmetrically rotatably connected to the side walls of the drive box, and the opposite ends of the connecting rods are rotatably connected to the corresponding pull rods. Through holes are symmetrically opened on the side of the cavity near the drive box, and push rods are slidably connected to the inner walls of the through holes. One end of each push rod contacts the side wall of the disc, and the other end contacts the end of the corresponding connecting rod. A tension spring is fixedly connected to the side wall of the disc near the drive box, and the other end of the tension spring is fixedly connected to the inner wall of the grouting pipe.

[0011] Preferably, the spoiler assembly includes: an extension rod, a second helical blade, and a spoiler plate. The extension rod is fixedly connected to the axis on the side of the disk away from the tension spring three. The second helical blade is fixedly connected to the outer wall of one end of the extension rod near the disk, and the spoiler plate is fixedly connected to the outer wall of the other end at equal intervals.

[0012] Preferably, an inner drill bit is slidably connected to the inner drill bit inside the outer drill bit, and guide rods are symmetrically fixedly connected to one end of the grouting pipe near the inner drill bit. Each guide rod has a sleeve on its outer wall, and a tension spring is fixedly connected to the inner wall of the sleeve. The other end of each tension spring is fixedly connected to the end of the corresponding guide rod.

[0013] Preferably, the end of the extrusion rod away from the sector plate is designed with a bevel, the position of the extrusion column near the extrusion rod is designed with a frustum, and it fits into the bevel end of the extrusion rod. The interior of the extrusion column is hollow.

[0014] Preferably, the outer wall of the sector plate is fitted with an elastic rubber pad.

[0015] A grouting method for a grouting device used for plugging water in the roof of a coal seam, comprising the following steps:

[0016] S1. Using the drilling exploration module of the grouting layer analysis station, combined with the geophysical exploration and drilling results of the mine working face roof, analyze and confirm the development of the original fractures in each layer of the coal seam roof, determine the grouting layer and range, move the trolley to the construction point, check the equipment connection, and mix the grouting material.

[0017] S2. Start the motor to drive the drill bit to rotate. The outer and inner drill bits work together to drill to the required depth so that the grout can be injected later. At the same time, the first spiral blade set on the outer wall of the grouting pipe will discharge the waste generated during drilling.

[0018] S3. Start the pump body to deliver slurry. The slurry is injected into the borehole through the slurry delivery pipe, cavity, and injection pipe via the drill bit. At the same time, the turbulence component prevents the slurry from settling. Slowly pull the handle to move the device outward and maintain continuous grouting to fill the borehole.

[0019] S4. When the drill bit moves close to the borehole opening, pull the tie rod. The drive assembly will cause the fan-shaped plate to unfold and press against the borehole wall. The rubber gasket will seal to prevent grout leakage. Continue grouting until the pressure reaches the set value and stabilizes, ensuring that the grout fully fills the cracks. The grouting pressure should reach 1.5 times the hydrostatic pressure, the grout intake should be less than 20L / min, and the maintenance time should be more than 20 minutes to end the grouting. At the same time, the grouting situation should be closely observed. If any abnormalities such as grout leakage or coal wall heave are found, grouting should be stopped in time and corresponding treatment measures should be taken.

[0020] S5. After grouting is completed, clean the grouting equipment in a timely manner to prevent the grout from solidifying and clogging inside the equipment, which would affect the next use. During cleaning, a cleaning solution can be used to rinse until all the grout inside the equipment is completely removed.

[0021] Compared with related technologies, the grouting device and grouting method for plugging water in the roof of the coal seam provided by the present invention have the following beneficial effects:

[0022] By integrating drilling and grouting functions into the same device, the drill bit at the end of the grouting pipe is driven by a motor to rotate to achieve drilling. The first spiral blade on the outer wall of the grouting pipe simultaneously completes the slag discharge. After drilling is completed, grouting can be performed directly without changing the equipment. This design reduces the time for equipment disassembly, installation and commissioning, improves construction efficiency, significantly shortens the project cycle and reduces time costs.

[0023] The designed sector-shaped plate sealing structure allows the drill bit to approach the borehole opening. By pulling the lever, a linkage mechanism is triggered, which in turn drives components such as the disc and extrusion column to work together. This causes the sector-shaped plate to expand outward against the tension of the tension spring, and the elastic rubber pad on its outer wall tightly adheres to the inner wall of the borehole, forming a reliable sealing structure. This effectively prevents grout leakage, ensures stable grouting pressure, and allows the grout to fully penetrate into the cracks in the top plate.

[0024] The turbulence-inducing components, second spiral blades, and turbulence plates stir and agitate the slurry, continuously mixing the slurry during the grouting process after relocation, preventing sedimentation and stratification, effectively ensuring the fluidity and injectability of the slurry, and ensuring that the slurry can spread evenly and fully fill the cracks during grouting; during the cleaning stage, the turbulence-inducing components assist the cleaning fluid in flushing the pipeline to ensure that there is no residual slurry. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the grouting device and grouting method for plugging water in the roof of the coal seam provided by the present invention;

[0026] Figure 2 for Figure 1 The diagram shows the structure of the drive box;

[0027] Figure 3 for Figure 2 The diagram shows a cross-sectional view of the grouting pipe.

[0028] Figure 4 for Figure 3 The diagram shows the structure at point A.

[0029] Figure 5 for Figure 2 The diagram shows the structure of the external drill bit;

[0030] Figure 6 for Figure 5 The diagram shows a cross-sectional view of the external drill bit.

[0031] Figure 7 for Figure 6 The diagram shows the structure at point B.

[0032] Figure 8 for Figure 5 The diagram shows a cross-sectional view of the mounting cylinder.

[0033] Figure 9 for Figure 8 The diagram shows the structure at point C.

[0034] Numbered in the diagram: 1. Trolley; 2. Mixing cylinder; 3. Pump body; 4. Grout delivery pipe; 5. Cavity; 6. Injection pipe; 7. External drill bit; 8. First spiral blade; 9. Fan-shaped plate; 10. Extrusion rod; 11. Extrusion column; 12. Tension spring one; 13. Connecting rod; 14. Disc; 15. Drive box; 16. Motor; 17. Handle; 18. Pull rod; 19. Connecting rod; 20. Top rod; 21. Tension spring three; 22. Extension rod; 23. Second spiral blade; 24. Baffle plate; 25. Internal drill bit; 26. Guide rod; 27. Sleeve; 28. Tension spring two; 29. ​​Mounting cylinder. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0036] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0037] Please see Figures 1 to 9A grouting device for plugging water in the roof of a coal seam, comprising: a trolley 1, a mixing cylinder 2 placed on top of the trolley 1, a pump body 3 connected to the bottom of the mixing cylinder 2 via a pipe, a grout delivery pipe 4 connected to the output end of the pump body 3, a cavity 5 connected to the other end of the grout delivery pipe 4, a grouting pipe 6 rotatably mounted inside the cavity 5, an external drill bit 7 for borehole grouting installed at the end of the grouting pipe 6, a first spiral blade 8 for discharging waste generated during borehole drilling installed on the outer wall of the grouting pipe 6, and fan-shaped plates 9 equidistantly arranged on the outer wall of the grouting pipe 6 near the external drill bit 7, a driving assembly installed between the fan-shaped plates 9 and the cavity 5, the driving assembly driving the fan-shaped plates 9 to expand outward and press against the inner wall of the borehole to prevent grout from leaking during grouting. The grout flows out of the borehole. A flow-turbulence component is installed inside the grouting pipe 6 near the cavity 5. This component is used to evenly mix the residual grout in the grouting pipe 4 and prevent sedimentation. The drive assembly includes: an extrusion rod 10, an extrusion column 11, a tension spring 12, a connecting rod 13, and a disc 14. An installation cylinder 29 is fixedly connected to the outer wall of the grouting pipe 6 near the outer drill bit 7. The other end of the installation cylinder 29 is fixedly connected to the outer drill bit 7. Equally spaced fan-shaped grooves are provided on the outside of the installation cylinder 29. Each fan-shaped plate 9 is placed in a corresponding fan-shaped groove. An extrusion rod 10 penetrating the inner wall of the grouting pipe 6 is fixedly connected to the inner wall of each fan-shaped plate 9. A tension spring 12 is fitted onto the outer wall of each extrusion rod 10. One end of each tension spring 12 is fixedly connected to the inner wall of a corresponding fan-shaped plate 9. All ends are fixedly connected to the grouting pipe 6. An extrusion column 11 is slidably connected to the inner wall of the grouting pipe 6 near the fan-shaped plate 9. A connecting rod 13 is symmetrically fixedly connected to the end of the extrusion column 11 away from the outer drill bit 7. A disc 14 is fixedly connected to the other end of the connecting rod 13. The disc 14 is placed inside the cavity 5 and tightly fitted to its inner wall. Grooves for grout flow are equidistantly opened on the grouting pipe 6 near the disc 14. These grooves are located inside the cavity 5. Connecting holes are equidistantly opened inside the disc 14. The grooved section of the grouting pipe 6 is slidably connected to the inner wall of the connecting holes of the disc 14. A drive box 15 is provided at the end of the grouting pipe 6 away from the outer drill bit 7. A motor 16 is fixedly connected inside the drive box 15, and the end of the grouting pipe 6 extends into the drive box 15. The internal part is fixedly connected to the output end of the motor 16. The end of the cavity 5 is fixedly connected to the side wall of the drive box 15 through the connecting bracket. Both sides of the drive box 15 are fixedly connected to handles 17. One side of each handle 17 is slidably connected to a pull rod 18. The side wall of the drive box 15 is symmetrically connected to connecting rods 19. The opposite ends of the connecting rods 19 are rotatably connected to the corresponding pull rods 18. The cavity 5 is symmetrically provided with through holes on the side near the drive box 15. The inner wall of each through hole is slidably connected to a top rod 20. One end of each top rod 20 contacts the side wall of the disc 14, and the other end contacts the end of the corresponding connecting rod 19. The side wall of the disc 14 near the drive box 15 is fixedly connected to a tension spring 21. The other end of the tension spring 21 is fixedly connected to the inner wall of the grouting pipe 6.An inner drill bit 25 is slidably connected to the inner drill bit 7. Guide rods 26 are symmetrically fixedly connected to one end of the grouting pipe 6 near the inner drill bit 25. Sleeves 27 are fitted onto the outer walls of the guide rods 26, and tension springs 28 are fixedly connected to the inner walls of the sleeves 27. The other ends of the tension springs 28 are fixedly connected to the corresponding ends of the guide rods 26. The ends of the extrusion rods 10 away from the sector plate 9 are all designed with a bevel. The extrusion column 11 near the extrusion rod 10 is designed as a frustum and fits against the beveled end of the extrusion rod 10. The interior of the extrusion column 11 is hollow. Elastic rubber pads are installed on the outer walls of the sector plate 9.

[0038] It should be noted that: the top of the trolley 1 is equipped with a storage battery to provide power output for the operation of the entire equipment; the outer wall of the external drill bit 7 is provided with a threaded groove to remove waste residue in time during drilling; the cavity 5 and the grouting pipe 6 are connected by a rotating seal, which does not affect the rotation of the grouting pipe 6 during drilling and prevents grout leakage during grouting.

[0039] Please see Figure 3 and Figure 4 The spoiler assembly includes: an extension rod 22, a second spiral blade 23, and a spoiler 24. An extension rod 22 is fixedly connected to the axis of the disk 14 away from the tension spring 21. A second spiral blade 23 is fixedly connected to the outer wall of one end of the extension rod 22 near the disk 14, and a spoiler 24 is fixedly connected to the outer wall of the other end at equal intervals.

[0040] It should be noted that: an extension rod 22 is fixedly connected to the axis of the disc 14 installed inside the cavity 5. A second spiral blade 23 is fixedly connected to the outer wall of one end of the extension rod 22 near the disc 14, and a baffle plate 24 is fixedly connected to the outer wall of the other end at equal intervals. The outer wall of the disc 14 and the inner wall of the cavity 5 are connected in a sliding seal. When the slurry enters the grouting pipe 6, the second spiral blade 23 stirs and pushes the slurry during the flow process, while the baffle plate 24 also agitates the slurry. The two work together to quickly mix the slurry evenly, effectively preventing sedimentation and stratification when the slurry remains in the grouting pipe 6, and ensuring the fluidity and injectability of the slurry.

[0041] A grouting method for a grouting device used for plugging water in the roof of a coal seam, comprising the following steps:

[0042] S1. Using the drilling exploration module of the grouting layer analysis station, combined with the geophysical exploration and drilling results of the mine working face roof, analyze and confirm the development of the original fractures in each layer of the front coal seam roof, determine the grouting layer and range, move the trolley 1 to the construction point, check the equipment connection, and mix the grouting material.

[0043] S2. Start motor 16 drives drill bit to rotate, outer drill bit 7 and inner drill bit 25 work together to drill to the required depth so that subsequent grout can be injected. At the same time, the waste generated during drilling is discharged through the first spiral blade 8 set on the outer wall of grouting pipe 6.

[0044] S3. Start pump body 3 to deliver slurry. The slurry is injected into the borehole through slurry delivery pipe 4, cavity 5, and injection pipe 6 via drill bit. At the same time, the turbulence component prevents the slurry from settling. Slowly pull handle 17 to move the device outward and maintain continuous grouting to fill the borehole.

[0045] S4. When the drill bit moves close to the borehole opening, pull the pull rod 18. The drive assembly will cause the fan-shaped plate 9 to unfold and press against the borehole wall. The rubber gasket will seal to prevent grout leakage. Continue grouting until the pressure reaches the set value and stabilizes, ensuring that the grout fully fills the cracks. The grouting pressure should reach 1.5 times the hydrostatic pressure, the grout intake should be less than 20L / min, and the maintenance time should be more than 20 minutes to end the grouting. At the same time, the grouting situation should be closely observed. If any abnormalities such as grout leakage or coal wall bulging are found, the grouting should be stopped in time and corresponding treatment measures should be taken.

[0046] S5. After grouting is completed, clean the grouting equipment in a timely manner to prevent the grout from solidifying and clogging inside the equipment, which would affect the next use. During cleaning, a cleaning solution can be used to rinse until all the grout inside the equipment is completely removed.

[0047] The working principle of the grouting device and grouting method for plugging water in the roof of the coal seam provided by this invention is as follows:

[0048] I. Positioning and Preparation Stage

[0049] In the process of water plugging operation on the roof of the coal seam before coal mining, the development of the original fractures in each layer of the roof of the coal seam is first analyzed in detail with the help of professional detection equipment to accurately determine the grouting layer and range. Then, the trolley 1, which is equipped with components such as mixing cylinder 2 and pump body 3, is moved to the designated construction point. The staff carefully checks whether the connection of each part of the equipment is firm. After confirming that there are no problems, the grouting material is mixed and prepared in mixing cylinder 2 to prepare for subsequent operations.

[0050] II. Drilling and Slag Removal Stage

[0051] The worker grips the handles 17 on both sides of the drive box 15 and aligns the external drill bit 7 with the top plate where drilling is required; the motor 16 inside the drive box 15 is started, and the output end of the motor 16 drives the grouting pipe 6 fixedly connected to it to rotate at high speed; the first spiral blade 8 fixedly connected to the outer wall of the grouting pipe 6 rotates synchronously, and at the same time, the mounting cylinder 29 fixedly installed at the end of the grouting pipe 6 and the external drill bit 7 also rotate together.

[0052] The outer drill bit 7 drives the inner drill bit 25 to rotate synchronously, and the two work closely together to perform drilling operations. During the drilling process, the inner drill bit 25 remains relatively stationary with the outer drill bit 7, without any relative slippage. The waste generated during drilling is discharged from the borehole along the spiral trajectory under the rotation of the first spiral blade 8, effectively preventing the accumulation of waste from affecting the drilling progress and quality, and ensuring the smooth progress of the drilling work. When the drilling reaches the predetermined depth, the motor 16 is turned off, and the drilling operation ends.

[0053] III. Grouting and Anti-Sedimentation Stage

[0054] After turning off the motor 16, start the pump body 3; the pump body 3 transports the slurry prepared inside the mixing cylinder 2 through the pipeline to the slurry delivery pipe 4, and then the slurry delivery pipe 4 transports it to the cavity 5 connected at its end; since the grouting pipe 6 has a groove for slurry flow near the disc 14 and the groove is located inside the cavity 5, the slurry can smoothly pass through the cavity 5 and enter the grouting pipe 6.

[0055] At this time, the turbulence-inducing component installed inside the grouting pipe 6 begins to function; an extension rod 22 is fixedly connected to the axis of the disc 14 installed inside the cavity 5, and a second spiral blade 23 is fixedly connected to the outer wall of one end of the extension rod 22 near the disc 14, and a turbulence-inducing plate 24 is fixedly connected to the outer wall of the other end at equal intervals; when the grout enters the grouting pipe 6, the second spiral blade 23 stirs and pushes the grout during the flow process, while the turbulence-inducing plate 24 also disturbs the grout. The two work together to quickly mix the grout evenly, effectively preventing sedimentation and stratification when the grout remains in the grouting pipe 6, and ensuring the fluidity and injectability of the grout;

[0056] The uniformly mixed slurry continues to move under the continuous pressure provided by the pump body 3. When the slurry reaches the drill bit end, the pressure of the slurry overcomes the tension of the tension spring 28, pushing the inner drill bit 25 open and allowing it to slide outward in the direction of drilling along the guide rod 26 inside the outer drill bit 7, while simultaneously stretching the tension spring 28. The extension of the inner drill bit 25 allows the slurry to flow smoothly into the borehole. During the grouting process, the operator holds the handle 17 and slowly pulls the grouting pipe 6 outward. The pump body 3 continues to work, allowing the slurry to be continuously injected into the borehole, gradually filling the internal space of the borehole.

[0057] IV. Orifice Sealing Stage

[0058] When the drill bit moves close to the borehole, the pull rod 18 is pulled; the pull rod 18 drives the connecting rod 19, which is rotatably connected to it, to rotate around the rotatable connection point with the side wall of the drive box 15. Using the lever principle, the end of the connecting rod 19 away from the pull rod 18 pushes the push rod 20 to move into the cavity 5; the movement of the push rod 20 pushes the disc 14 to slide inside the cavity 5, at which time the tension spring 3 21 fixedly connected to the disc 14 is stretched;

[0059] The disc 14 drives the extrusion column 11 at its end to move outward toward the drill bit 7 via the connecting rod 13; the outer wall of the extrusion column 11 is a frustum design, and as the extrusion column 11 moves, its frustum-shaped outer wall fits against the inclined end of the extrusion rod 10, and extrudes the extrusion rod 10 fixedly connected to the inner wall of the fan-shaped plate 9; since the end of the extrusion rod 10 is inclined, matching the frustum design of the extrusion column 11, under the extrusion action of the extrusion column 11, the extrusion rod 10 moves outward toward the grouting pipe 6, and at the same time drives the fan-shaped plate 9 to expand outward against the tension of the tension spring 12;

[0060] The outer wall of the fan-shaped plate 9 is equipped with an elastic rubber pad. Under the action of the extrusion rod 10, the elastic rubber pad firmly presses against the inner wall of the borehole to form a sealing structure, effectively preventing the grout from overflowing from the borehole during the grouting process, ensuring the grouting effect, and continuing to maintain grouting so that the grout inside the borehole can penetrate into the crack.

[0061] V. Grouting Completion and Repositioning Stage

[0062] During the grouting process, the staff closely monitors the grouting pressure and grout intake. When the grouting pressure reaches 1.5 times the hydrostatic pressure and the grout intake is less than 20 L / min, the pump body 3 is shut off to stop grouting. After releasing the pull rod 18, the tension spring 21 releases its tension, restoring the initial state and driving the disc 14 to move in the opposite direction. The disc 14 drives the extrusion column 11 to reset through the connecting rod 13. At this time, the extrusion column 11 disengages from the extrusion rod 10, the tension spring 12 releases its tension, driving the sector plate 9 to reset, so that the device returns to its initial state. At this time, the pressure of the grout inside the grouting pipe 6 on the inner drill bit 25 disappears, the tension spring 28 releases its tension, and pulls the inner drill bit 25 to reset. After that, wait for the grout to solidify, remove the drill bit and seal the hole to complete the grouting operation.

[0063] VI. Cleaning and Maintenance Stage

[0064] After the grouting operation is completed, in order to prevent the grout from solidifying and clogging inside the equipment and affecting the next use, the grouting device needs to be cleaned with cleaning fluid in a timely manner. Inject cleaning fluid into the mixing tank 2, start the pump body 3, and let the cleaning fluid pass through the entire pipeline system to flush the mixing tank 2, pump body 3, grout delivery pipe 4, cavity 5 and grouting pipe 6 and other components. During the cleaning process, the turbulence component continues to play its role, assisting the cleaning fluid to better flush the inside of the pipeline, ensuring that all the grout inside the equipment is completely removed, extending the service life of the equipment, and preparing for the next grouting operation.

[0065] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A grouting device for plugging water in the roof of a coal seam, comprising: A trolley (1) is provided with a mixing cylinder (2) on top of the trolley (1). The bottom of the mixing cylinder (2) is connected to a pump body (3) via a pipe. The output end of the pump body (3) is connected to a grouting pipe (4). The other end of the grouting pipe (4) is connected to a cavity (5). A grouting pipe (6) is rotatably installed inside the cavity (5). An external drill bit (7) for drilling grouting is installed at the end of the grouting pipe (6). A first spiral blade (8) for discharging waste generated during drilling is installed on the outer wall of the grouting pipe (6). A fan-shaped plate (9) is provided at equal intervals on the outer wall of the end of the grouting pipe (6) near the external drill bit (7). A drive assembly is installed between the fan-shaped plate (9) and the cavity (5). The drive assembly drives the fan-shaped plate (9) to expand outward and press against the inner wall of the borehole to prevent the grout from flowing out of the borehole during grouting. A turbulence maker is installed inside the end of the grouting pipe (6) near the cavity (5). The turbulence maker is used to evenly mix the grout remaining in the grouting pipe (4) to prevent it from settling. The drive assembly includes: an extrusion rod (10), an extrusion column (11), a tension spring (12), a connecting rod (13), and a disc (14). An installation cylinder (29) is fixedly connected to the outer wall of one end of the grouting pipe (6) near the outer drill bit (7). The other end of the installation cylinder (29) is fixedly connected to the outer drill bit (7). Equally spaced fan-shaped grooves are provided on the outside of the installation cylinder (29). Each fan-shaped plate (9) is placed in a corresponding fan-shaped groove. An extrusion rod (10) penetrating the inner wall of the grouting pipe (6) is fixedly connected to the inner wall of each fan-shaped plate (9). 10) The outer wall is fitted with tension spring 1 (12). One end of tension spring 1 (12) is fixedly connected to the inner wall of the corresponding sector plate (9), and the other end is fixedly connected to the grouting pipe (6). The inner wall of the grouting pipe (6) near the sector plate (9) is slidably connected to an extrusion column (11). The end of the extrusion column (11) away from the outer drill bit (7) is symmetrically fixedly connected to a connecting rod (13). The other end of the connecting rod (13) is fixedly connected to a disc (14). The disc (14) is placed inside the cavity (5) and is tightly fitted to its inner wall. The spoiler assembly includes: an extension rod (22), a second helical blade (23), and a spoiler (24). The extension rod (22) is fixedly connected to the axis on the side of the disk (14) away from the tension spring (21). The second helical blade (23) is fixedly connected to the outer wall of one end of the extension rod (22) near the disk (14), and the spoiler (24) is fixedly connected to the outer wall of the other end at equal intervals. The inner drill bit (25) is slidably connected to the inner drill bit (7). The grouting pipe (6) is symmetrically fixedly connected to one end of the inner drill bit (25). The outer wall of the guide rod (26) is fitted with a sleeve (27). The inner wall of the sleeve (27) is fixedly connected with a tension spring (28). The other end of the tension spring (28) is fixedly connected to the end of the corresponding guide rod (26).

2. The grouting device for plugging water in the roof of the coal seam according to claim 1, characterized in that, The grouting pipe (6) has grooves at equal intervals near the disc (14) for grout flow. The grooves are located inside the cavity (5). The disc (14) has connecting holes at equal intervals inside. The grooved section of the grouting pipe (6) is slidably connected to the inner wall of the connecting hole of the disc (14).

3. The grouting device for plugging water in the roof of the coal seam according to claim 1, characterized in that, A drive box (15) is provided at the end of the grouting pipe (6) away from the external drill bit (7). A motor (16) is fixedly connected inside the drive box (15). The end of the grouting pipe (6) extends into the drive box (15) and is fixedly connected to the output end of the motor (16). The end of the cavity (5) is fixedly connected to the side wall of the drive box (15) through a connecting frame.

4. The grouting device for plugging water in the roof of the coal seam according to claim 3, characterized in that, Both sides of the drive box (15) are fixedly connected to handles (17), and one side of each handle (17) is slidably connected to a pull rod (18). The side wall of the drive box (15) is symmetrically connected to a connecting rod (19). The opposite ends of the connecting rod (19) are slidably connected to the corresponding pull rod (18). The cavity (5) is symmetrically provided with through holes on the side near the drive box (15). The inner wall of each through hole is slidably connected to a top rod (20). One end of the top rod (20) is in contact with the side wall of the disc (14), and the other end is in contact with the end of the corresponding connecting rod (19). The side wall of the disc (14) near the drive box (15) is fixedly connected to a tension spring (21), and the other end of the tension spring (21) is fixedly connected to the inner wall of the grouting pipe (6).

5. The grouting device for plugging water in the roof of the coal seam according to claim 1, characterized in that, The end of the extrusion rod (10) away from the fan-shaped plate (9) is designed with a bevel. The position of the extrusion column (11) near the extrusion rod (10) is designed with a frustum and fits against the bevel end of the extrusion rod (10). The interior of the extrusion column (11) is hollow.

6. The grouting device for plugging water in the roof of the coal seam according to claim 1, characterized in that, Elastic rubber pads are installed on the outer wall of the fan-shaped plate (9).

7. The grouting method of the grouting device for plugging water in the roof of the coal seam according to any one of claims 1-6, characterized in that, Includes the following steps: S1. By using the drilling and exploration module of the grouting layer analysis station, combined with the geophysical exploration and drilling results of the mine working face roof, analyze and confirm the development of the original fractures in each layer of the coal seam roof, determine the grouting layer and range, move the trolley (1) to the construction point, check the equipment connection, and mix the grouting material. S2. Start the motor (16) to drive the drill bit to rotate. The outer drill bit (7) and the inner drill bit (25) work together to drill to the required depth so that the subsequent grout can be injected. At the same time, the waste generated during drilling is discharged through the first spiral blade (8) set on the outer wall of the grouting pipe (6). S3. Start the pump body (3) to transport the slurry. The slurry is injected into the borehole through the slurry delivery pipe (4), cavity (5), and injection pipe (6) via the drill bit. At the same time, the turbulence component prevents the slurry from settling. Slowly pull the handle (17) to move the device outward and maintain continuous grouting to fill the borehole. S4. When the drill bit moves close to the hole opening, pull the pull rod (18) to make the fan plate (9) unfold and press against the hole wall through the drive component. The rubber gasket seals to prevent grout leakage. Continue grouting until the pressure reaches the set value and stabilizes to ensure that the grout fully fills the cracks. The grouting pressure reaches 1.5 times the hydrostatic pressure, the grout intake is less than 20L / min, and the maintenance time is more than 20min to end the grouting. At the same time, the grouting situation should be closely observed. If grout leakage or abnormal coal wall heave is found, the grouting should be stopped in time and corresponding treatment measures should be taken. S5. After grouting is completed, clean the grouting equipment in a timely manner to prevent the grout from solidifying and clogging inside the equipment, which would affect the next use. During cleaning, a cleaning solution can be used to rinse until all the grout inside the equipment is completely removed.

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