Underground drilling dust-falling blowout preventer for soft coal seam

Abstract

The invention relates to the technical field of roadway drilling safety, and discloses a soft coal seam underground drilling dust-falling blowout preventer which comprises a drill rod and an auxiliary assembly used in cooperation with the drill rod, the auxiliary assembly comprises a fixing flange, and the fixing flange is fixedly installed on a roadway wall near a drill hole; an adjusting assembly is fixedly installed on the fixed flange and comprises a fixed plate and a movable plate, the fixed plate is fixedly installed on the side, away from the sliding bin, of the fixed flange, a sealing bag is fixedly installed between the fixed plate and the movable plate, a plurality of fixing holes are formed in the fixed plate, and the movable plate is fixedly installed on the fixed plate. And a plurality of insertion rods are fixedly mounted on the movable plate. The movable plate is matched with the sealing bag. When shrinkage or collapse occurs in the drilled hole, the movable plate is matched with the sealing bag, so that the sealing bag moves and is arranged on the outer side of the movable plate in a sleeving mode, and the effects of improving the sealing performance and reducing gas and coal leakage are achieved.

Description

Technical Field

[0001] This invention relates to the field of tunnel drilling safety technology, specifically a dust suppression and blowout prevention device for drilling in soft coal seams. Background Technology

[0002] During underground drilling operations, the gas and broken coal in the coal and rock strata are prone to creating a high-pressure environment under the stress of the ground and the disturbance of the drill bit. During drilling, various reasons may cause blowouts, resulting in a large amount of gas and coal dust being released instantly. This can not only damage the equipment, but may also cause gas exceedances or even explosions, thereby threatening the lives of workers, disrupting production order, and reducing production efficiency.

[0003] Existing technologies mostly achieve blowout prevention through sealing orifices and simple barriers. A common method is to inject materials such as yellow mud into the orifice to seal the coal seam fissures. However, traditional sealing materials solidify slowly, have unstable sealing performance, and are generally inefficient in preventing blowouts, still posing risks of excessive gas levels and dust pollution.

[0004] Existing blowout preventers mostly seal the borehole exit with baffles or bladders, supplemented by other supporting structures, to achieve blowout prevention. However, in soft coal seams, the stability of the coal seam is poor, and collapse and narrowing of the borehole are prone to occur, resulting in an increase in the diameter of the borehole opening. At this time, the fixed-area baffles and bladders can no longer seal the exit, and gas and coal can easily leak out from the gaps between the baffles or bladders and the borehole wall, which may lead to problems such as excessive gas levels, affecting normal production, and even endangering the life and health of workers. Summary of the Invention

[0005] In view of this, a dust suppression and blowout prevention device for drilling in soft coal seams is proposed to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a dust suppression and blowout prevention device for drilling in soft coal seams, comprising a drill rod and auxiliary components used in conjunction with it, the auxiliary components comprising a fixed flange, a sliding chamber and an installation chamber connected sequentially to the fixed flange, a sealing plate fixedly installed on the installation chamber, and further comprising:

[0007] An indicator component is installed on the outer wall of the installation chamber to display the status of the nozzles in conjunction with the components inside the installation chamber;

[0008] A buffer assembly, disposed inside the sliding chamber, is used to deflect part of the impact force during nozzle ejection;

[0009] The fixed flange is fixedly installed on the tunnel wall near the borehole. An adjustment assembly is fixedly installed on the fixed flange. The adjustment assembly includes a fixed plate and a movable plate. The fixed plate is fixedly installed on the side of the fixed flange away from the sliding chamber. A sealing bag is fixedly installed between the fixed plate and the movable plate. The fixed plate has multiple fixing holes, and the movable plate has multiple insert rods fixedly installed.

[0010] Preferably, the sealing bag is a circular ring with a circular cross-section.

[0011] Preferably, the sealed bag is a ring with a trapezoidal cross-section.

[0012] Preferably, the indicator component includes an air outlet, which is fixedly installed on the outer wall of the installation chamber. An indicator bag is fixedly installed on the air outlet, and an air guide tube is fixedly installed at the end of the indicator bag away from the air outlet. The air guide tube is connected to an external storage mechanism.

[0013] Preferably, the buffer assembly includes a pressure plate that is slidably mounted on the inner wall of the sliding chamber. A buffer spring is fixedly mounted on the side of the pressure plate away from the fixed flange, and the end of the buffer spring away from the pressure plate is fixedly connected to the inner wall of the sliding chamber.

[0014] Preferably, the buffer assembly includes a pressure plate that is slidably mounted on the inner wall of the sliding chamber. A buffer spring assembly is fixedly mounted on the side of the pressure plate away from the fixed flange. The end of the buffer spring assembly away from the pressure plate is fixedly connected to the inner wall of the sliding chamber. A plurality of connecting rods are fixedly mounted on the pressure plate. A blocking plate is fixedly mounted on the end of each connecting rod away from the pressure plate. The blocking plate is slidably mounted on the inner wall of the installation chamber.

[0015] Preferably, both the pressure plate and the baffle plate are provided with multiple filter holes.

[0016] Preferably, a plurality of locking blocks are fixedly installed on the inner wall of the sliding chamber located on the side of the pressure plate near the borehole, and one side of the locking blocks is in contact with the pressure plate.

[0017] Preferably, the inner wall of the installation chamber is provided with multiple air vents, and the air vent is inserted into the air vent.

[0018] Preferably, when in the initial position, the baffle plate is located near the air outlet of the sliding chamber.

[0019] Compared with the prior art, the present invention provides a dust suppression and blowout prevention device for drilling in soft coal seams, which has the following beneficial effects:

[0020] 1. This invention utilizes the cooperation of a movable plate and a sealing bag. When borehole shrinkage or collapse occurs, the movable plate and the sealing bag work together to move the sealing bag, which then fits over the outside of the movable plate, thereby improving sealing performance and reducing gas and coal leakage.

[0021] 2. This invention utilizes the cooperation of a fixed plate, a movable plate, and a sealing bag. When a borehole shrinks or collapses, the cooperation of the fixed plate, movable plate, and sealing bag causes the sealing bag to deform, but its position remains between the fixed plate and the movable plate. This improves the sealing performance and reduces the probability of the sealing bag rupture.

[0022] 3. By combining the pressure plate and the buffer spring assembly, this invention reduces the damage to the device caused by the impact of gas and coal during a blowout, thereby reducing economic losses.

[0023] 4. This invention, through the cooperation of a baffle plate and an indicator component, allows workers to judge the severity of a blowout by observing the expansion of the indicator bags on different indicator components when a blowout occurs. This eliminates the need for excessive additional components to determine the condition and stage of the blowout, thereby reducing economic losses and improving work efficiency. Attached Figure Description

[0024] Figure 1 This is an overall structural diagram of the present invention;

[0025] Figure 2 This is an overall structural diagram of the present invention when the indicator component is installed;

[0026] Figure 3 This is an overall structural diagram of an adjustment component according to the present invention;

[0027] Figure 4 This is an overall structural diagram of another adjustment component of the present invention;

[0028] Figure 5 A cross-sectional view of another sealing bag according to the present invention;

[0029] Figure 6 This is an internal structural diagram of the present invention without the indicator component installed;

[0030] Figure 7 This is a diagram showing the internal structure of the sliding chamber when the indicator component is installed according to the present invention;

[0031] Figure 8 This is an internal structural diagram of the installation compartment when installing the indicator component of the present invention.

[0032] In the picture:

[0033] 1. Drill pipe; 2. Fixed flange; 21. Adjustment assembly; 211. Fixed plate; 212. Moving plate; 213. Fixed hole; 214. Insert rod; 215. Sealing bag;

[0034] 3. Sliding chamber; 4. Installation chamber; 5. Sealing plate;

[0035] 6. Indicator assembly; 61. Air outlet; 62. Indicator bag; 63. Air duct;

[0036] 7. Buffer assembly; 71. Pressure plate; 72. Buffer spring; 73. Buffer spring assembly; 74. Connecting rod; 75. Locking block; 76. Baffle plate; 77. Vent. Detailed Implementation

[0037] 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.

[0038] like Figures 1 to 8 As shown, this embodiment of the invention provides a dust suppression and blowout prevention device for drilling in soft coal seams, including a drill pipe 1 and auxiliary components used in conjunction with it. The auxiliary components include a fixed flange 2, a sliding chamber 3 and an installation chamber 4 connected sequentially to the fixed flange 2, a sealing plate 5 fixedly installed on the installation chamber 4, and further include:

[0039] Indicator component 6 is installed on the outer wall of the installation chamber 4 and is used to display the status of the nozzles in conjunction with the components inside the installation chamber 4;

[0040] The buffer assembly 7 is located inside the sliding chamber 3 and is used to absorb part of the impact force when the nozzle is sprayed.

[0041] The fixed flange 2 is fixedly installed on the tunnel wall near the borehole. An adjustment assembly 21 is fixedly installed on the fixed flange 2. The adjustment assembly 21 includes a fixed plate 211 and a movable plate 212. The fixed plate 211 is fixedly installed on the side of the fixed flange 2 away from the sliding chamber 3. A sealing bag 215 is fixedly installed between the fixed plate 211 and the movable plate 212. Multiple fixing holes 213 are opened on the fixed plate 211, and multiple insertion rods 214 are fixedly installed on the movable plate 212.

[0042] The working principle and beneficial effects of the above technical solution are as follows: The fixed flange 2 is fixedly installed on the roadway wall near the borehole. When a blowout occurs in the borehole, the impact force of the airflow will hit the adjusting component 21 on the fixed flange 2, which will drive the insert rod 214 on the moving plate 212 to slide in the fixing hole 213 on the fixed plate 211. That is, the fixed plate 211 and the moving plate 212 will have relative displacement. At this time, the sealing bag 215 will expand outward under the squeezing action of the two, so that the borehole can be sealed when a blowout occurs and the borehole expands and collapses, reducing the probability of gas leakage.

[0043] In one embodiment, the sealing bag 215 is a circular ring with a circular cross-section.

[0044] The working principle and beneficial effects of the above technical solution are as follows: Before drilling, the geology at the drilling site is surveyed. When the geology is relatively intact, the sealing bag 215 is selected as a circular ring with a circular cross-section. The sealing bag 215 is placed slightly outside the center of the fixed plate 211 and the moving plate 212. When squeezed, the sealing bag 215 will expand outward. When it reaches the limit, a small part of the sealing bag 215 will be clamped by the fixed plate 211 and the moving plate 212, and most of the sealing bag 215 will be located between the moving plate 212 and the hole wall after the hole is enlarged, thus achieving the sealing of the gap.

[0045] In one embodiment, the sealing bag 215 is a ring with a trapezoidal cross-section.

[0046] The working principle and beneficial effects of the above technical solution are as follows: Before drilling, the geology at the drilling site is surveyed. When the geology is relatively broken, the sealing bag 215 is selected as a ring with a trapezoidal cross-section. The sealing bag 215 is placed at the center of the fixed plate 211 and the moving plate 212. When squeezed, the sealing bag 215 will expand outward. When it reaches the limit, the sealing bag 215 will wrap around the side of the moving plate 212 that is close to the fixed plate 211, thus sealing the gap. Since the sealing bag 215 is located between the moving plate 212 and the fixed plate 211, the coal carried by the airflow will not come into direct contact with the sealing bag 215, reducing the possibility of the sealing bag 215 being torn by the coal.

[0047] In one embodiment: the indicator component 6 includes an air outlet 61, which is fixedly installed on the outer wall of the installation chamber 4. An indicator bag 62 is fixedly installed on the air outlet 61. An air guide tube 63 is fixedly installed at the end of the indicator bag 62 away from the air outlet 61, and the air guide tube 63 is connected to an external storage mechanism.

[0048] The working principle and beneficial effects of the above technical solution are as follows: After the airflow enters the installation chamber 4, it enters the indicator bag 62 through the air outlet 61, and then enters the external storage mechanism through the air guide pipe 63. The expansion of the indicator bag 62 can be used to determine whether there is gas flowing through the nozzle of the indicator component 6.

[0049] In one embodiment: the buffer assembly 7 includes a pressure plate 71, which is slidably mounted on the inner wall of the sliding chamber 3. A buffer spring 72 is fixedly mounted on the side of the pressure plate 71 away from the fixed flange 2, and the end of the buffer spring 72 away from the pressure plate 71 is fixedly connected to the inner wall of the sliding chamber 3.

[0050] The working principle and beneficial effects of the above technical solution are as follows: When the airflow enters the sliding chamber 3, it will impact the pressure plate 71, thereby driving the buffer spring 72 to compress. Under the buffering effect of the buffer spring 72 and the pressure plate 71, the impact on the device is reduced and the service life of the device is extended.

[0051] In one embodiment: the buffer assembly 7 includes a pressure plate 71, which is slidably mounted on the inner wall of the sliding chamber 3. A buffer spring assembly 73 is fixedly mounted on the side of the pressure plate 71 away from the fixed flange 2. The end of the buffer spring assembly 73 away from the pressure plate 71 is fixedly connected to the inner wall of the sliding chamber 3. A plurality of connecting rods 74 are fixedly mounted on the pressure plate 71. A baffle plate 76 is fixedly mounted on the end of the connecting rod 74 away from the pressure plate 71. The baffle plate 76 is slidably mounted on the inner wall of the installation chamber 4.

[0052] The working principle and beneficial effects of the above technical solution are as follows: When the airflow enters the sliding chamber 3, it will impact the pressure plate 71, which will in turn drive the buffer spring group 73 to compress. Under the buffering effect of the buffer spring group 73 and the pressure plate 71, the impact on the device is reduced and the service life of the device is extended. At the same time, when the pressure plate 71 moves, it will drive the connecting rod 74 to move, which will in turn drive the baffle plate 76 to move, making the buffering effect better.

[0053] In one embodiment, both the pressure plate 71 and the baffle plate 76 are provided with multiple filter holes.

[0054] The working principle and beneficial effects of the above technical solution are as follows: Due to the relatively loose soil in the soft coal seam, under the impact of the airflow from the nozzle, some solid materials will move along with the airflow from the nozzle. When passing through the pressure plate 71, the filter holes on the pressure plate 71 will filter some of the materials, preventing larger solid materials from entering the sliding chamber 3 and causing the device to jam. The diameter of the filter holes on the baffle plate 76 is smaller than the diameter of the filter holes on the pressure plate 71. Smaller solid materials can be stored in the installation chamber 4 for subsequent collection.

[0055] In one embodiment, a plurality of locking blocks 75 are fixedly installed on the inner wall of the sliding chamber 3 located on the side of the pressure plate 71 near the borehole, and one side of the locking block 75 is in contact with the pressure plate 71.

[0056] The working principle and beneficial effects of the above technical solution are as follows: After the spraying is completed, the pressure plate 71 will be reset under the action of the buffer spring group 73. The locking block 75 can prevent the pressure plate 71 from being over-impacted on the front adjustment component 21 and causing damage. At the same time, after the locking block 75 collides with the reset pressure plate 71, it can shake off some of the solid material adhering to the pressure plate 71 to prevent blockage.

[0057] In one embodiment: a plurality of air vents 77 are provided on the inner wall of the installation chamber 4, and the air vent 61 is inserted into the air vent 77.

[0058] The working principle and beneficial effects of the above technical solution are as follows: when the baffle plate 76 is located at the air outlet 77, the air outlet 77 cannot play a connecting role, and the indicator bag 62 on the indicator component 6 will not change in volume.

[0059] In one embodiment: when in the initial position, the baffle plate 76 is located near the air outlet 77 of the sliding chamber 3.

[0060] The working principle and beneficial effects of the above technical solution are as follows: When a jet occurs, the baffle plate 76 is moved by the gas impact. When it is in the initial stage of the jet, the movement of the baffle plate 76 will connect the initial air outlet 77 with the air nozzle 61. At this time, the indicator bag 62 at this location will expand, and the expansion speed is relatively fast, which can indicate the occurrence of the jet. At the same time, the indicator bag 62 at the other air outlet 77 will also expand, but the expansion speed is slower. If the jet pressure is high, the baffle plate 76 will move to the maximum position, that is, to the farthest air outlet 77. At this time, the farthest... The indicator bag 62 will stop expanding, and the expansion status of the indicator bag 62 can be used to determine the maximum pressure of the nozzle for early prevention. When the nozzle enters the stabilization stage, the expansion rate of the two indicator bags 62 is stable. If the pressure at the stabilization stage causes the baffle plate 76 to move to the maximum position, when the nozzle enters the decay period, the farthest indicator bag 62 will collide but at a slow speed, and then the nearest indicator bag 62 will stop expanding after a certain period of time. The above are some common situations, not all situations, but the condition of the nozzle can still be judged by the expansion status of the two indicator bags 62.

[0061] Working principle and usage process: The fixed flange 2 is fixedly installed on the tunnel wall near the borehole. When a blowout occurs in the borehole, the impact force of the airflow will hit the adjusting component 21 on the fixed flange 2, which will cause the insert rod 214 on the moving plate 212 to slide in the fixing hole 213 on the fixed plate 211. That is, the fixed plate 211 and the moving plate 212 are relatively displaced. At this time, the sealing bag 215 will expand outward under the squeezing action of the two, so that the borehole can be sealed when a blowout occurs and the borehole expands or collapses, reducing the probability of gas leakage.

[0062] Based on the above, before drilling, the geology at the drilling site is surveyed. When the geology is relatively intact, the sealing bag 215 is a circular ring with a circular cross-section. The sealing bag 215 is placed slightly outside the center of the fixed plate 211 and the moving plate 212. When squeezed, the sealing bag 215 will expand outward. When it reaches its limit, a small part of the sealing bag 215 will be clamped by the fixed plate 211 and the moving plate 212, and most of the sealing bag 215 will be located between the moving plate 212 and the hole wall after the hole is enlarged, thus achieving the sealing of the gap.

[0063] Before drilling, the geology at the drilling site is surveyed. When the geology is relatively fragmented, the sealing bag 215 is a trapezoidal ring. The sealing bag 215 is placed at the center of the fixed plate 211 and the moving plate 212. When squeezed, the sealing bag 215 will expand outward. When it reaches its limit, the sealing bag 215 will wrap around the side of the moving plate 212 that is close to the fixed plate 211, thus sealing the gap. Since the sealing bag 215 is located between the moving plate 212 and the fixed plate 211, the coal carried by the airflow will not come into direct contact with the sealing bag 215, reducing the possibility of the sealing bag 215 being torn by the coal.

[0064] In addition, after the airflow enters the installation chamber 4, it enters the indicator bag 62 through the air outlet 61, and then enters the external storage mechanism through the air guide tube 63. The expansion of the indicator bag 62 can be used to determine whether there is gas flowing through the nozzle of the indicator component 6.

[0065] Furthermore, when a nozzle erupts, the baffle plate 76 is moved by the gas impact. In the initial stage of the nozzle eruption, the movement of the baffle plate 76 connects the initial vent 77 with the vent nozzle 61. At this time, the indicator bag 62 at this location will expand rapidly, indicating the occurrence of a nozzle eruption. Simultaneously, the indicator bag 62 at the other vent 77 will also expand, but at a slower rate. If the nozzle pressure is high, the baffle plate 76 will move to its maximum position, i.e., to the furthest vent 77. At this point, the furthest indicator bag 62 will... Once expansion stops, the maximum pressure of the nozzle can be determined by observing the expansion of the indicator bag 62, allowing for early prevention. When the nozzle enters the stabilization phase, the expansion rate of the two indicator bags 62 stabilizes. If the pressure at the stabilization point causes the baffle plate 76 to move to its maximum position, the farthest indicator bag 62 will collide with the nozzle during the nozzle decay period, albeit at a slower speed. Then, the nearest indicator bag 62 will stop expanding after a certain period. These are some common scenarios, not all, but the condition of the nozzle can still be determined by observing the expansion of the two indicator bags 62.

[0066] Finally, when the airflow enters the sliding chamber 3, it impacts the pressure plate 71, which in turn compresses the buffer spring assembly 73. Under the buffering effect of the buffer spring assembly 73 and the pressure plate 71, the impact on the device is reduced, and the service life of the device is extended. At the same time, when the pressure plate 71 moves, it will drive the connecting rod 74 to move, which in turn drives the baffle plate 76 to move, making the buffering effect better. After the spraying ends, the pressure plate 71 will reset under the action of the buffer spring assembly 73. The locking block 75 can prevent the pressure plate 71 from excessively impacting the front adjustment component 21 and causing damage. At the same time, after the locking block 75 collides with the reset pressure plate 71, it can shake off some of the solid material adhering to the pressure plate 71, preventing blockage.

[0067] 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 dust suppression and blowout prevention device for drilling in soft coal seams, comprising a drill rod (1) and auxiliary components used in conjunction with it, the auxiliary components comprising a fixed flange (2), a sliding chamber (3) and an installation chamber (4) sequentially connected to the fixed flange (2), and a sealing plate (5) fixedly installed on the installation chamber (4), characterized in that, Also includes: Indicator component (6) is disposed on the outer wall of the mounting chamber (4) and is used to display the status of the nozzle in conjunction with the components inside the mounting chamber (4); A buffer assembly (7) is disposed inside the sliding chamber (3) to deflect part of the impact force when the nozzle is sprayed. The fixed flange (2) is fixedly installed on the roadway wall near the borehole. An adjustment assembly (21) is fixedly installed on the fixed flange (2). The adjustment assembly (21) includes a fixed plate (211) and a movable plate (212). The fixed plate (211) is fixedly installed on the side of the fixed flange (2) away from the sliding chamber (3). A sealing bag (215) is fixedly installed between the fixed plate (211) and the movable plate (212). Multiple fixing holes (213) are opened on the fixed plate (211). Multiple insertion rods (214) are fixedly installed on the movable plate (212).

2. The dust suppression and blowout prevention device for drilling in soft coal seams according to claim 1, characterized in that: The sealed bag (215) is a circular ring with a circular cross-section.

3. The dust suppression and blowout prevention device for drilling in soft coal seams according to claim 1, characterized in that: The sealed bag (215) is a ring with a trapezoidal cross-section.

4. The dust suppression and blowout prevention device for drilling in soft coal seams according to claim 3, characterized in that: The indicator component (6) includes an air outlet (61), which is fixedly installed on the outer wall of the installation chamber (4). An indicator bag (62) is fixedly installed on the air outlet (61), and an air guide tube (63) is fixedly installed at one end of the indicator bag (62) away from the air outlet (61). The air guide tube (63) is connected to an external storage mechanism.

5. The dust suppression and blowout prevention device for drilling in soft coal seams according to claim 4, characterized in that: The buffer assembly (7) includes a pressure plate (71), which is slidably installed on the inner wall of the sliding chamber (3). A buffer spring (72) is fixedly installed on the side of the pressure plate (71) away from the fixed flange (2), and the end of the buffer spring (72) away from the pressure plate (71) is fixedly connected to the inner wall of the sliding chamber (3).

6. The dust suppression and blowout prevention device for drilling in soft coal seams according to claim 4, characterized in that: The buffer assembly (7) includes a pressure plate (71), which is slidably mounted on the inner wall of the sliding chamber (3). A buffer spring assembly (73) is fixedly mounted on the side of the pressure plate (71) away from the fixed flange (2). The end of the buffer spring assembly (73) away from the pressure plate (71) is fixedly connected to the inner wall of the sliding chamber (3). A plurality of connecting rods (74) are fixedly mounted on the pressure plate (71). A baffle plate (76) is fixedly mounted on the end of the connecting rod (74) away from the pressure plate (71). The baffle plate (76) is slidably mounted on the inner wall of the installation chamber (4).

7. A dust suppression and blowout prevention device for drilling in soft coal seams according to claim 6, characterized in that: Both the pressure plate (71) and the baffle plate (76) are provided with multiple filter holes.

8. The dust suppression and blowout prevention device for drilling in soft coal seams according to claim 7, characterized in that: Multiple locking blocks (75) are fixedly installed on the inner wall of the sliding chamber (3) located on the side of the pressure plate (71) near the borehole, and one side of the locking block (75) is in contact with the pressure plate (71).

9. A dust suppression and blowout prevention device for drilling in soft coal seams according to claim 8, characterized in that: The inner wall of the installation chamber (4) is provided with multiple air vents (77), and the air vent (61) is inserted into the air vents (77).

10. A dust suppression and blowout prevention device for drilling in soft coal seams according to claim 9, characterized in that: When in the initial position, the baffle plate (76) is located near the air outlet (77) of the sliding chamber (3).

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