Grouting device for overlying strata isolation grouting filling

Abstract

The invention relates to the technical field of grouting and filling, and discloses a grouting device for overlying strata isolation grouting and filling, which comprises a drill bit and further comprises a hollow drill rod, grouting holes, a connecting structure and a backflow pipe sleeve are equidistantly formed in the outer side of the hollow drill rod, and backflow holes and a flow guide switching structure are equidistantly formed in the inner side of the backflow pipe sleeve. The flow guide switching structure allows flushing water to pass through, the flushing water can enter the drill bit, during grouting, the flow guide switching structure prevents slurry from passing through, the slurry enters the overburden mining-induced fracture space through the grouting hole, and during flushing, the flow guide switching structure prevents the flushing water from passing through, and the flushing water enters the backflow pipe sleeve through the grouting hole and the backflow hole. Through cooperative cooperation of the drill bit, the hollow drill rod, the connecting structure, the flow guide switching structure and the backflow pipe sleeve, the hollow drill rod is lifted upwards to adjust the axial position, opening and closing of a grouting hole and on-off switching of a flow guide channel can be completed, and therefore integrated continuous operation of the three working procedures of drilling, grouting and flushing is achieved.

Description

Technical Field

[0001] This invention relates to the field of grouting and filling technology, and more specifically, to a grouting device for grouting and filling overburden isolation. Background Technology

[0002] The overburden isolation grouting filling technology uses fly ash bulk dry material as raw material. After mixing the raw material with water to make grout, it is injected into the mining-induced fracture space of the overburden below the key layer. Under high pressure, the grout compacts the broken and swollen rock mass below the key layer to form a support body, producing a "pressing down and supporting up" effect. It forms a compacted bearing structure in the goaf, thereby preventing the key layer from fracturing, achieving the purpose of controlling surface subsidence, and realizing coal mining without demolition.

[0003] In existing technologies, when filling the overburden mining fracture space, fly ash or gangue powder is usually mixed with water to form a grout, which is then transported through a grouting pipe and injected into the overburden mining fracture space below the key layer.

[0004] In the process of grouting and filling the fractured space of overburden through grouting pipes, for complex strata such as fractured zones and loose deposits in the overburden, the traditional method of drilling and withdrawing tools can easily lead to the collapse of the borehole wall, causing the grouting pipe to fail to reach the correct position and thus interrupting the operation. Moreover, prolonged grouting can cause a large amount of fly ash / gangue powder to accumulate in the grouting pipe, narrowing the grouting channel inside the grouting pipe, which will affect the grouting volume and grouting pressure, i.e., affect the control of grouting parameters. Therefore, a grouting device for overburden isolation grouting and filling that can perform drilling, grouting, and flushing operations in one go is needed. Summary of the Invention

[0005] This invention provides a grouting device for grouting and filling overburden isolation, which solves the technical problems in related technologies where the removal of the drilling tool can easily affect the overburden isolation grouting operation, and prolonged grouting can lead to the deposition of a large amount of fly ash / gangue powder in the grouting pipe, which can easily affect the grouting parameters.

[0006] This invention provides a grouting device for grouting and filling of overburden isolation, including a drill bit and a hollow drill rod disposed outside the drill bit, wherein grouting holes are equidistantly opened on the outer side of the hollow drill rod;

[0007] A connecting structure is provided between the drill bit and the hollow drill rod;

[0008] A reflux sleeve is fitted over the outside of the hollow drill rod, and reflux holes are equidistantly opened on the inner side of the reflux sleeve;

[0009] A flow-guiding and switching structure is installed inside the hollow drill rod. During drilling, the flow-guiding and switching structure allows flushing water to pass through and enter the drill bit. During grouting, the flow-guiding and switching structure obstructs the passage of grout, which enters the overburden mining fracture space through the grouting hole. During flushing, the flow-guiding and switching structure obstructs the passage of flushing water, which enters the return pipe sleeve through the grouting hole and the return hole.

[0010] Preferably, the grouting hole is inclined through the hollow drill rod, and the grout output end of the grouting hole faces the drilling direction of the drill bit.

[0011] Preferably, the connection structure includes a threaded sleeve that is threaded to the drill bit connection end, and a limiting sleeve that is fixedly connected to the hollow drill rod. A connecting sleeve is fixedly connected to the outside of the threaded sleeve. A limiting groove is formed on the outer side of the threaded sleeve and the inner side of the connecting sleeve. The limiting sleeve is slidably connected inside the limiting groove. A connecting rod A is fixedly connected at equal intervals to the outer side of the connecting sleeve. The end of the connecting rod A away from the connecting sleeve is fixedly connected to the return pipe sleeve.

[0012] Preferably, the connecting rod A and the grouting hole are staggered in the circumferential direction of the hollow drill rod.

[0013] Preferably, the return hole can be aligned with the grouting hole, and a sealing ring that can fit against the outer wall of the hollow drill rod is provided on the outside of the return hole.

[0014] Preferably, the flow guiding and switching structure includes a piston rod that slides inside the hollow drill rod and can block the grouting hole. The piston rod has an annular groove on its outside. A connecting pipe that is fixedly connected to a threaded sleeve is slidably connected inside the annular groove. A snap-fit ​​component is provided between the piston rod and the connecting pipe. A flow guiding channel is provided inside the piston rod. A sealing component is provided inside the flow guiding channel.

[0015] Preferably, the snap-fit ​​component includes damping grooves equidistantly disposed inside the piston rod and snap-fit ​​grooves equidistantly disposed inside the connecting pipe. The two ends of the damping groove are respectively connected to an annular groove and a flow guide channel. A snap-fit ​​protrusion capable of entering the snap-fit ​​groove is slidably connected inside the damping groove.

[0016] Preferably, the flow channel is composed of a cylindrical section near the threaded sleeve and a conical section away from the threaded sleeve, with the conical section of the flow channel narrowing away from the threaded sleeve.

[0017] Preferably, the sealing component includes a connecting frame fixedly connected inside the hollow drill rod, and a sealing block extending into the guide channel is fixedly connected to the middle of the connecting frame via a connecting rod B. The sealing block has an inner groove equidistantly opened on its outer side, and the end of the snap-fit ​​protrusion away from the snap-fit ​​groove can enter the inner groove.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. This invention employs a combination of a drill bit, a hollow drill rod, and a flow-guiding switching structure. The drill bit is used for drilling, during which the piston rod is sealed outside the grouting hole, and the flow-guiding channel is in an open state. The flushing water inside the hollow drill rod enters the drill bit through the flow-guiding channel and is discharged through the slag discharge hole on the drill bit. This allows the flushing water to carry rock slag and be discharged upward through the gap between the hollow drill rod and the borehole wall, thereby achieving slag discharge during the drilling process.

[0020] 2. This invention employs a combination of hollow drill rods, connecting structures, and flow-guiding switching structures. By lifting the hollow drill rod and moving it upwards a predetermined distance, the grouting hole is opened, and the flow-guiding channel is blocked. The grout inside the hollow drill rod then enters the overburden mining fracture space through the grouting hole. Furthermore, the blocking of the flow-guiding channel prevents grout from entering the drill bit and causing grout deposition inside the drill bit, thereby achieving grouting work after drilling.

[0021] 3. This invention employs a combination of hollow drill rods, a flow-guiding switching structure, and a return pipe sleeve. By lifting the hollow drill rod and moving it upwards a predetermined distance, the opened grouting hole is aligned with the return hole, and the flow-guiding channel is blocked. The flushing water inside the hollow drill rod then flushes the interior of the hollow drill rod and enters the return pipe sleeve through the grouting hole and the return hole. Furthermore, the blocking of the flow-guiding channel prevents the flushing water from entering the grout filling space through the drill bit and affecting the grouting filling quality, thereby achieving the flushing work after grouting.

[0022] This invention achieves integrated continuous operation of drilling, grouting, and flushing processes by coordinating the drill bit, hollow drill rod, connecting structure, flow guiding and switching structure, and return pipe sleeve, and by adjusting the axial position of the hollow drill rod by lifting it. 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 first structural schematic diagram of the present invention during drilling;

[0025] Figure 3 This is a schematic diagram of the second structure during drilling according to the present invention;

[0026] Figure 4 for Figure 3 Enlarged view of the structure at point A in the image;

[0027] Figure 5 This is a schematic diagram of the structure during grouting in this invention;

[0028] Figure 6 This is a schematic diagram of the structure during rinsing according to the present invention.

[0029] In the diagram: 10. Drill bit; 20. Hollow drill rod; 21. Grouting hole; 30. Connecting structure; 31. Threaded sleeve; 32. Limiting sleeve; 33. Connecting sleeve; 34. Limiting groove; 35. Connecting rod A; 40. Return pipe sleeve; 41. Return hole; 50. Flow guiding and switching structure; 51. Piston column; 52. Connecting pipe; 53. Flow guiding channel; 54. Snap-fit ​​groove; 55. Snap-fit ​​protrusion; 56. Connecting frame; 57. Connecting rod B; 58. Block; 59. Embedded groove. Detailed Implementation

[0030] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, some features described in the examples may be combined in other examples.

[0031] like Figure 1 - Figure 6 As shown, this embodiment provides a grouting device for grouting and filling of overburden isolation, including a drill bit 10. Multiple slag discharge holes are equidistantly opened at the drilling end of the drill bit 10. This embodiment requires the use of surface equipment, which is existing technology. The specific structure of the surface equipment is not described in detail in this embodiment. It also includes:

[0032] Hollow drill rod 20 is set outside drill bit 10. Grouting holes 21 are equidistantly opened on the outer side of hollow drill rod 20. The grouting holes 21 are inclined through hollow drill rod 20, and the grout output end of grouting hole 21 faces the drilling direction of drill bit 10. The inclined grouting holes 21 can make the grout diffuse radially into the mining fracture space of overburden to form a cone-shaped diffusion zone, thereby improving the overall density and continuity of overburden isolation layer.

[0033] The connecting structure 30 is disposed between the drill bit 10 and the hollow drill rod 20;

[0034] A return pipe sleeve 40 is fitted over the hollow drill rod 20. Return holes 41 are equidistantly opened on the inner side of the return pipe sleeve 40. The return holes 41 can be aligned with the grouting holes 21. A sealing ring is provided on the outside of the return holes 41 to fit against the outer wall of the hollow drill rod 20. When the grouting holes 21 and the return holes 41 are aligned, the sealing ring can seal the joint between the grouting holes 21 and the return holes 41 to prevent flushing water from leaking from the gap between the grouting holes 21 and the return holes 41.

[0035] The flow-directing switching structure 50 is installed inside the hollow drill rod 20. During drilling, the flow-directing switching structure 50 allows flushing water to pass through and enter the drill bit 10. During grouting, the flow-directing switching structure 50 obstructs the passage of grout, which enters the overburden mining fracture space through the grouting hole 21. During flushing, the flow-directing switching structure 50 obstructs the passage of flushing water, which enters the return pipe sleeve 40 through the grouting hole 21 and the return hole 41.

[0036] This implementation, through the coordinated operation of drill bit 10, hollow drill rod 20, connecting structure 30, flow guiding and switching structure 50 and return pipe sleeve 40, can realize the integrated continuous operation of drilling, grouting and flushing processes.

[0037] The connecting structure 30 includes a threaded sleeve 31 that is threaded to the connecting end of the drill bit 10, and a limiting sleeve 32 that is fixedly connected to the hollow drill rod 20. A connecting sleeve 33 is fixedly connected to the outside of the threaded sleeve 31. The outer diameter of the connecting sleeve 33 is adapted to the outer diameter of the return pipe sleeve 40 and is smaller than the inner diameter of the drill hole of the drill bit 10. A limiting groove 34 is opened on the outer side of the threaded sleeve 31 and the inner side of the connecting sleeve 33. The limiting sleeve 32 is slidably connected inside the limiting groove 34. Through the axial limiting effect of the limiting sleeve 32 and the limiting groove 34, it can be ensured that the hollow drill rod 20 and the connecting sleeve 33 do not separate during assembly and operation.

[0038] Connecting rods A35 are fixedly connected at equal intervals on the outer side of the connecting sleeve 33. The connecting rods A35 and the grouting hole 21 are staggered in the circumferential direction of the hollow drill rod 20 to avoid obstructing the grout output from the grouting hole 21. The end of the connecting rod A35 away from the connecting sleeve 33 is fixedly connected to the return pipe sleeve 40.

[0039] That is, the connecting structure 30 is fixedly connected to the drill bit 10 and the return pipe sleeve 40, and the connecting structure 30 is slidably connected to the hollow drill rod 20.

[0040] The flow guiding and switching structure 50 includes a piston rod 51 that slides inside the hollow drill rod 20 and can seal the grouting hole 21. An annular groove is provided on the outside of the piston rod 51. A connecting pipe 52 that is fixedly connected to the threaded sleeve 31 is slidably connected inside the annular groove. A snap-fit ​​component is provided between the piston rod 51 and the connecting pipe 52. A flow guiding channel 53 is provided inside the piston rod 51. The flow guiding channel 53 consists of a cylindrical section close to the threaded sleeve 31 and a conical section away from the threaded sleeve 31. The conical section of the flow guiding channel 53 narrows away from the threaded sleeve 31. A sealing component is provided inside the flow guiding channel 53.

[0041] When the drill bit 10 is driven by surface equipment to drill, the drill bit 10 is pressed against the rock strata, the hollow drill rod 20 is pressed against the end of the threaded sleeve 31, and the piston column 51 is sealed on the outside of the grouting hole 21. At the same time, the piston column 51 and the connecting pipe 52 are retracted to their shortest state, and maintaining the shortest state between the piston column 51 and the connecting pipe 52 requires the use of a clamping device, specifically as follows: Figure 2 - Figure 3 As shown, the flushing water inside the hollow drill rod 20 can enter the drill bit 10 through the guide channel 53 and be discharged through the slag discharge hole on the drill bit 10, so that the flushing water carries the rock slag and is discharged upward through the gap between the hollow drill rod 20 and the borehole wall, so as to achieve slag discharge during the drilling process.

[0042] When the hollow drill rod 20 is raised a predetermined distance by the surface equipment, the hollow drill rod 20 moves the grouting hole 21 away from the piston column 51, and also moves the sealing component to seal the guide channel 53 (during this process, the piston column 51 and the connecting pipe 52 are still kept in the shortest state by the snap-fit ​​component), so that the grouting hole 21 is opened and the guide channel 53 is sealed, as detailed below. Figure 5 As shown, grout can then be injected into the hollow drill rod 20 through surface equipment, allowing the grout to enter the overburden mining fracture space through the grouting hole 21 to achieve grouting after drilling;

[0043] When the hollow drill rod 20 is raised by the surface equipment to move it a predetermined distance, the hollow drill rod 20 moves the grouting hole 21 closer to the return hole 41, and the piston rod 51 moves away from the drill bit 10 simultaneously through the sealing component (during this process, the piston rod 51 and the connecting pipe 52 are no longer locked together by the snap-fit ​​component), so that the opened grouting hole 21 is aligned with the return hole 41, as shown in the following details. Figure 6 As shown, flushing water can then be injected into the hollow drill rod 20 through surface equipment, so that the flushing water washes the inside of the hollow drill rod 20 and enters the return pipe sleeve 40 through the grouting hole 21 and the return hole 41 to achieve flushing after grouting.

[0044] The snap-fit ​​component includes damping grooves equidistantly opened inside the piston rod 51 and snap-fit ​​grooves 54 equidistantly opened inside the connecting pipe 52. The two ends of the damping groove are respectively connected to the annular groove and the flow channel 53. A snap-fit ​​protrusion 55 that can enter the snap-fit ​​groove 54 is slidably connected inside the damping groove. When the snap-fit ​​protrusion 55 enters the snap-fit ​​groove 54, the piston rod 51 and the connecting pipe 52 cannot slide relative to each other.

[0045] When drilling with drill bit 10, one end of the locking protrusion 55 is located inside the locking groove 54, and the other end abuts against the outside of the sealing block 58. When grouting with hollow drill rod 20, one end of the locking protrusion 55 is still located inside the locking groove 54, and the other end is aligned with the outside of the embedded groove 59. When flushing with hollow drill rod 20, one end of the locking protrusion 55 disengages from the locking groove 54, and the other end enters the locking groove 54.

[0046] The sealing component includes a connecting frame 56 fixedly connected inside the hollow drill rod 20. A sealing block 58 extending into the guide channel 53 is fixedly connected to the middle of the connecting frame 56 via a connecting rod B57. When the sealing block 58 moves away from the drill bit 10 along with the hollow drill rod 20, it can seal the guide channel 53. An inner groove 59 is provided at equal intervals on the outer side of the sealing block 58. The end of the snap-fit ​​protrusion 55 away from the snap-fit ​​groove 54 can enter the inner groove 59.

[0047] When drilling through the drill bit 10, the flow channel 53 is in the open state. When grouting is performed through the hollow drill rod 20, the flow channel 53 is blocked by the sealing block 58 to prevent grout from entering the interior of the drill bit 10 and causing grout to accumulate inside the drill bit 10. When flushing through the hollow drill rod 20, the flow channel 53 is also blocked by the sealing block 58 to prevent flushing water from entering the grout filling space through the drill bit 10 and affecting the grouting filling quality.

[0048] The specific working principle of this implementation is as follows: the grouting device in its initial state is as follows: Figure 1 As shown, when the drill bit 10 is driven by the surface equipment to drill, the drill bit 10 is pressed against the rock strata, causing the threaded sleeve 31 connected to its end to abut against the end of the hollow drill rod 20. The piston rod 51 is sealed outside the grouting hole 21, and the flow channel 53 is open. Simultaneously, one end of the locking protrusion 55 is located inside the locking groove 54, and the other end abuts against the outside of the sealing block 58. That is, during this process, the piston rod 51 and the connecting pipe 52 are kept at their shortest distance by the locking mechanism, specifically as follows... Figure 2 - Figure 4 As shown, flushing water is injected into the hollow drill rod 20 through the surface equipment. The flushing water inside the hollow drill rod 20 enters the drill bit 10 through the guide channel 53 and is discharged through the slag discharge hole on the drill bit 10. This allows the flushing water to carry rock slag and be discharged upward through the gap between the hollow drill rod 20 and the borehole wall, so as to achieve slag discharge during the drilling process.

[0049] After drilling is completed, the hollow drill rod 20 is raised by the surface equipment, moving it upward a predetermined distance. This causes the hollow drill rod 20 to move the grouting hole 21 away from the piston column 51 (during this process, the limiting sleeve 32 slides inside the limiting groove 34). The connecting frame 56 and connecting rod B57 then drive the sealing block 58 to seal the guide channel 53, opening the grouting hole 21 and sealing the guide channel 53. During this process, one end of the snap-fit ​​protrusion 55 remains inside the snap-fit ​​groove 54, while the other end changes from abutting against the outside of the sealing block 58 to aligning with the outside of the embedded groove 59. In other words, the piston column 51 and the connecting pipe 52 remain in their shortest possible position through the snap-fit ​​mechanism. Specifically... Figure 5 As shown, grout can then be injected into the hollow drill rod 20 through surface equipment. The grout inside the hollow drill rod 20 enters the overburden mining fracture space through the grouting hole 21, and the guide channel 53 is blocked by the sealing block 58 to prevent the grout from entering the drill bit 10 and causing grout to accumulate inside the drill bit 10, thereby achieving grouting after drilling.

[0050] After a prolonged grouting process, grout will accumulate inside the hollow drill rod 20. When the hollow drill rod 20 is further lifted by surface equipment to move it a predetermined distance, it will cause the grouting hole 21 to approach the return hole 41 (during this process, the limiting sleeve 32 slides inside the limiting groove 34). Simultaneously, the sealing block 58 will cause the piston rod 51 to move away from the drill bit 10. During this process, one end of the locking protrusion 55 disengages from the locking groove 54, and the other end enters the locking groove 54. That is, the piston rod 51 and the connecting pipe 52 are no longer locked together by the locking component, allowing the opened grouting hole 21 to align with the return hole 41. Specifically, as shown... Figure 6 As shown, flushing water can then be injected into the hollow drill rod 20 through surface equipment. The flushing water inside the hollow drill rod 20 will flush the inside of the hollow drill rod 20 and enter the return pipe sleeve 40 through the grouting hole 21 and the return hole 41. The guide channel 53 is also blocked by the sealing block 58 to prevent the flushing water from entering the grout filling space through the drill bit 10 and affecting the grouting filling quality, thereby achieving flushing after grouting.

[0051] After the flushing work is completed, the hollow drill rod 20 can be lowered by the surface equipment to move it down a predetermined distance, so that the grouting hole 21 is reopened. Then, grout can be injected into the hollow drill rod 20 through the surface equipment to continue the grouting and filling work.

[0052] The embodiments of the present invention have been described above, but the embodiments are not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the embodiments described above, all of which are within the protection scope of the embodiments described above.

Claims

1. A grouting device for grouting and filling overburden isolation, comprising a drill bit (10), characterized in that, Also includes: A hollow drill rod (20) is disposed outside the drill bit (10), and grouting holes (21) are provided at equal intervals on the outer side of the hollow drill rod (20). A connecting structure (30) is disposed between the drill bit (10) and the hollow drill rod (20); A return pipe sleeve (40) is sleeved on the outside of the hollow drill rod (20), and return holes (41) are opened at equal intervals on the inner side of the return pipe sleeve (40). A flow-directing switching structure (50) is installed inside the hollow drill rod (20). During drilling, the flow-directing switching structure (50) allows flushing water to pass through and enter the drill bit (10). During grouting, the flow-directing switching structure (50) obstructs the passage of grout, and the grout enters the overburden mining fracture space through the grouting hole (21). During flushing, the flow-directing switching structure (50) obstructs the passage of flushing water, and the flushing water enters the return pipe sleeve (40) through the grouting hole (21) and the return hole (41).

2. The grouting device for grouting and filling overburden isolation according to claim 1, characterized in that, The grouting hole (21) is inclined through the hollow drill rod (20), and the grout output end of the grouting hole (21) is oriented toward the drilling direction of the drill bit (10).

3. A grouting device for grouting and filling overburden isolation according to claim 2, characterized in that, The connection structure (30) includes a threaded sleeve (31) that is threaded to the end of the drill bit (10) and a limiting sleeve (32) that is fixedly connected to the hollow drill rod (20). A connecting sleeve (33) is fixedly connected to the outside of the threaded sleeve (31). A limiting groove (34) is opened on the outer side of the threaded sleeve (31) and the inner side of the connecting sleeve (33). The limiting sleeve (32) is slidably connected inside the limiting groove (34). A connecting rod A (35) is fixedly connected at equal intervals to the outer side of the connecting sleeve (33). The end of the connecting rod A (35) away from the connecting sleeve (33) is fixedly connected to the return pipe sleeve (40).

4. A grouting device for grouting and filling overburden isolation according to claim 3, characterized in that, The connecting rod A (35) and the grouting hole (21) are staggered in the circumferential direction of the hollow drill rod (20).

5. A grouting device for grouting and filling overburden isolation according to claim 4, characterized in that, The return hole (41) can be aligned with the grouting hole (21), and the outside of the return hole (41) is provided with a sealing ring that can fit against the outer wall of the hollow drill rod (20).

6. A grouting device for grouting and filling overburden isolation according to claim 5, characterized in that, The flow-guiding switching structure (50) includes a piston column (51) that slides inside the hollow drill rod (20) and can seal the grouting hole (21). An annular groove is provided on the outside of the piston column (51). A connecting pipe (52) that is fixedly connected to the threaded sleeve (31) is slidably connected inside the annular groove. A snap-fit ​​component is provided between the piston column (51) and the connecting pipe (52). A flow-guiding channel (53) is provided inside the piston column (51). A sealing component is provided inside the flow-guiding channel (53).

7. A grouting device for grouting and filling overburden isolation according to claim 6, characterized in that, The snap-fit ​​component includes a damping groove equidistantly disposed inside the piston rod (51) and a snap-fit ​​groove (54) equidistantly disposed inside the connecting pipe (52). The two ends of the damping groove are respectively connected to the annular groove and the flow channel (53). A snap-fit ​​protrusion (55) that can enter the snap-fit ​​groove (54) is slidably connected inside the damping groove.

8. A grouting device for grouting and filling overburden isolation according to claim 7, characterized in that, The flow channel (53) consists of a cylindrical section near the threaded sleeve (31) and a conical section away from the threaded sleeve (31), with the conical section of the flow channel (53) narrowing away from the threaded sleeve (31).

9. A grouting device for grouting and filling overburden isolation according to claim 8, characterized in that, The sealing component includes a connecting frame (56) fixedly connected inside the hollow drill rod (20). A sealing block (58) extending into the guide channel (53) is fixedly connected to the middle of the connecting frame (56) via a connecting rod B (57). An embedded groove (59) is provided at equal intervals on the outer side of the sealing block (58). The end of the snap-fit ​​protrusion (55) away from the snap-fit ​​groove (54) can enter the embedded groove (59).

Images