A coal seam bedding drilling hole orifice dust removal device and method

Abstract

The present application relates to a kind of coal seam bedding borehole orifice dust removal device and method, belong to coal seam bedding borehole construction dust prevention technical field, orifice dust removal device includes telescopic dust removal device, telescopic dust removal device includes flexible bag, multiple water sprayers are installed in flexible bag, the upper side and the lower side of flexible bag are equipped with gas outlet and slag outlet respectively;Telescopic dust removal device is close to the one end of borehole orifice and is equipped with the detachable connection of expansion assembly, expansion assembly includes the cylinder of the inner diameter greater than the outer diameter of drill rod and the bladder around cylinder, bladder is equipped with inflation port to realize the expansion of expansion assembly by injecting fluid into bladder through inflation port and expansion fixed;Telescopic dust removal device is equipped with connection assembly to realize dynamic seal connection with drill rod at the end away from borehole orifice.The present application has good dust removal effect, solves the problem of coal seam bedding borehole orifice dust, and orifice dust removal device can be folded, with the characteristics of light weight, convenient to carry.

Description

Technical Field

[0001] This invention belongs to the field of dust control technology in coal seam drilling, and relates to a dust removal device and method for the borehole opening of coal seam drilling. Background Technology

[0002] During drilling operations in soft coal seams, due to the fragility of the coal seam, hydraulic slag removal drilling along the seam is prone to phenomena such as blowouts, hole collapses, and stuck drill bits. In actual practice, pneumatic slag removal is often used to improve the borehole success rate. However, using pneumatic slag removal to drill holes can easily generate a large amount of coal dust at the borehole opening, affecting the visibility of construction personnel and leading to potential safety hazards on site. In addition, dust entering the roadway can cause great harm to the health of drilling personnel and roadway workers.

[0003] Existing orifice dust removal devices mainly use mechanical bolt connections, which are bulky and difficult to transport during on-site construction. They are also quite complicated to connect to extraction boreholes, and the on-site application effect is not ideal. In particular, when a large number of boreholes are drilled along the coal seam in the working face, the amount of work involved in transporting the drilling rig and dust removal system is large, which is not conducive to on-site work. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a dust removal device and method for coal seam boreholes along the seam, so as to solve the problem that existing borehole dust removal devices are bulky and difficult to transport.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A dust removal device for coal seam borehole openings includes a retractable dust removal device comprising a flexible bag with multiple water sprayers installed inside. The upper and lower sides of the flexible bag are respectively provided with an air outlet and a slag outlet. An expansion assembly is detachably connected to the end of the retractable dust removal device near the borehole opening. The expansion assembly includes a cylinder with an inner diameter larger than the outer diameter of the drill rod and a bag surrounding the cylinder. The bag has an inflation port to inject fluid into the bag, thereby expanding and fixing the expansion assembly. A connecting assembly is provided at the end of the retractable dust removal device away from the borehole opening to achieve a dynamic sealing connection with the drill rod.

[0007] Optionally, the connecting assembly includes a mounting sleeve. An elastic sleeve is provided on the inner side of the end of the mounting sleeve away from the flexible bag. The elastic sleeve includes a conical section and a cylindrical section connected to the large end of the conical section. The cylindrical section is located at the end of the conical section away from the flexible bag. Multiple sliders are fixedly connected to the outer wall of the elastic sleeve corresponding to the conical section. A groove corresponding to the position of the slider is provided on the inner wall of the mounting sleeve. A slide rod is provided in the groove, which is arranged parallel to the axial direction of the elastic sleeve. The slider is provided with a sliding opening that matches the slide rod. A spring is sleeved on the slide rod to make the elastic sleeve fit against the drill rod. The two ends of the spring are connected to the slider and the inner wall of the groove, respectively.

[0008] Optionally, a sealing ring is provided at the end of the elastic sleeve away from the flexible bag.

[0009] Optionally, it also includes a water supply assembly for supplying water to the sprayers. The water supply assembly includes a high-pressure pipe with an inlet at one end and branch pipes on the lower side of the high-pressure pipe in the same number as the number of sprayers. The branch pipes are provided with connectors for detachable connection to the sprayers. A second gate valve is provided at the inlet.

[0010] Optionally, the water sprayer includes a main ring body, with a water inlet at the top and multiple nozzles surrounding the edge of the main ring body.

[0011] Optionally, the inflation port can be connected to a downhole medium-pressure air pipe to inject medium-pressure air into the bag through the downhole medium-pressure air pipe; a first gate valve is provided at the inflation port.

[0012] Optionally, the expansion assembly and the retractable dust removal device are connected by hooking or plugging.

[0013] Optionally, the expansion component and the retractable dust removal device are connected by a hook and ring structure. The hook and ring structure includes multiple rings fixedly connected to one end of the bag near the retractable dust removal device, and multiple hooks fixedly connected to the flexible bag and matched with the rings.

[0014] Optionally, the water inlet of the water supply component can be connected to the water inlet pipe of the drilling rig operating platform to supply water to the water supply component through the water inlet pipe of the drilling rig operating platform.

[0015] A method for dust removal at the borehole opening of a coal seam in-seam drilling operation is provided, comprising the above-described dust removal device. When drilling a coal seam in-seam drilling operation with a borehole diameter of d1, after the drilling depth exceeds 1.5 to 2 times the length L1 of the expansion assembly's cylinder, the drill bit and drill rod are removed, a new drill bit is installed, and the borehole opening is enlarged until the hole length is L1 and the hole diameter is d2. Then, the drill bit and drill rod are removed, the expansion assembly is installed, and medium-pressure air is injected into the bladder of the expansion assembly through a downhole medium-pressure air pipe until the expansion assembly expands and is fixed at the borehole diameter of d2. Inside the borehole, a retractable dust removal device is connected, which is then connected to a water supply assembly. The inlet of the water supply assembly is connected to the water inlet pipe of the drilling rig's operating platform. During drilling, compressed air enters through the drill rod. Under the action of air pressure, coal slag, gas, and air are discharged from the borehole and enter the retractable dust removal device. The coal slag settles under the action of dust removal water sprayed from the water sprayer of the retractable dust removal device and is discharged from the slag outlet of the retractable dust removal device. Air and gas are discharged through an external extraction pipeline connected to the air outlet of the retractable dust removal device.

[0016] The beneficial effects of this invention are: it can effectively reduce coal dust in the borehole and roadway coal seam, with good dust removal effect, solving the problem of dust at the borehole opening of the coal seam in the same direction, and the dust removal device at the borehole opening is foldable, lightweight and easy to transport.

[0017] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0018] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0019] Figure 1 This is a schematic diagram of the structure of a coal seam in-seam borehole dust removal device according to the present invention;

[0020] Figure 2 This is a longitudinal cross-sectional view of the expansion component;

[0021] Figure 3 This is a cross-sectional view of the expansion component;

[0022] Figure 4 This is a front view of the expansion component;

[0023] Figure 5 This is a schematic diagram of the water supply components;

[0024] Figure 6 This is a schematic diagram of the retractable dust removal device.

[0025] Figure 7 This is a schematic diagram of the water sprayer.

[0026] Figure 8 for Figure 6 A magnified view of part A.

[0027] Reference numerals: 1. Drill bit; 2. Drill rod; 3. Compressed air; 4. Cinder; 5. Hole wall; 6. Expansion assembly; 601. Bag; 602. Cylinder; 603. Inflation port; 604. Hanging ring; 605. First gate valve; 606. Air; 7. Connecting assembly; 701. Mounting sleeve; 702. Elastic sleeve; 703. Slider; 704. Sliding rod; 705. Spring; 706. Sealing ring; 8. Water supply assembly; 801. Connector; 802. High-pressure pipe; 803. Second gate valve; 804. Water inlet; 804. Telescopic dust removal device; 9. Hook; 901. Flexible bag; 902. Water sprayer; 903. Air outlet; 904. Slag outlet; 905. Water injection port; 931. Nozzle; 932. Main ring body; 933. Drilling rig; 10. Detailed Implementation

[0028] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0030] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0031] Please see Figure 1 A dust removal device for coal seam boreholes includes a retractable dust removal device 9, which comprises a flexible bag 902. Multiple water sprayers 903 are installed inside the flexible bag 902. An air outlet 904 and a slag outlet 905 are respectively provided on the upper and lower sides of the flexible bag 902. An expansion component 6, detachably connected to the end of the retractable dust removal device 9 near the borehole opening, is provided. The expansion component 6 includes a cylinder with an inner diameter larger than the outer diameter of a drill rod 2 and a bag 601 arranged around the cylinder. An inflation port 603 is provided on the bag 601 to inject fluid into the bag 601, thereby expanding and fixing the expansion component 6. A connecting component 7 is provided at the end of the retractable dust removal device 9 away from the borehole opening to achieve a dynamic sealing connection with the drill rod 2. The drill rod 2 is connected to the output end of a drilling rig 10, and a drill bit 1 is fixedly connected to the end of the drill rod 2 away from the drilling rig 10.

[0032] The dust removal device at the borehole opening of this invention can effectively reduce coal dust in the borehole opening and roadway coal seam, with good dust removal effect. It solves the problem of dust at the borehole opening of the coal seam in the same direction. Moreover, the dust removal device at the borehole opening is foldable, lightweight and easy to transport.

[0033] The structure of the connecting component 7 can be as follows: it includes a mounting sleeve 701, an elastic sleeve 702 is provided on the inner side of the end of the mounting sleeve 701 away from the flexible bag 902, the elastic sleeve 702 includes a conical section and a cylindrical section connected to the large end of the conical section, the cylindrical section is located at the end of the conical section away from the flexible bag 902, a plurality of sliders 703 are fixedly connected to the outer wall of the elastic sleeve 702 corresponding to the conical section, a groove is provided on the inner wall of the mounting sleeve 701 corresponding to the position of the slider 703, a slide rod 704 arranged parallel to the axial direction of the elastic sleeve 702 is fixedly connected in the groove, the slider 703 is provided with a sliding opening that matches the slide rod 704, a spring 705 is sleeved on the slide rod 704 to make the elastic sleeve 702 fit with the drill rod 2, the two ends of the spring 705 are fixedly connected to the slider 703 and the inner wall of the groove respectively; a sealing ring 706 is provided at the end of the elastic sleeve 702 away from the flexible bag 902.

[0034] The water sprayer 903 in this invention is supplied with water through a water supply assembly 8. The water supply assembly 8 includes a high-pressure pipe 802, one end of which has a water inlet 804. The lower side of the high-pressure pipe 802 has the same number of branch pipes as the number of water sprayers 903. Each branch pipe has a connector 801 for detachable connection to the water sprayer 903. A second gate valve 803 is provided at the water inlet 804. The water sprayer 903 includes a main ring body 933, with a water inlet 931 at its top. Multiple nozzles 932 are arranged around the edge of the main ring body 933. The water inlet 804 of the water supply assembly 8 can be connected to the water inlet pipe of the drilling rig operating platform to supply water to the water supply assembly 8 through the drilling rig operating platform's water inlet pipe.

[0035] The air inlet 603 of this invention can be connected to the underground medium-pressure air pipe to inject medium-pressure air 606 into the bag 601 through the underground medium-pressure air pipe; a first gate valve 605 is provided at the air inlet 603.

[0036] The expansion component 6 and the retractable dust removal device 9 in this invention can be detachably connected by hooking or plugging. The hooking method can be achieved by fixing multiple hanging rings 604 to one end of the pouch 601 of the expansion component 6 near the retractable dust removal device 9, and fixing multiple hooks 901 matching the hanging rings 604 to the flexible bag 902 of the retractable dust removal device 9. The connection between the expansion component 6 and the retractable dust removal device 9 is achieved through the connection between the hooks 901 and the hanging rings 604.

[0037] A method for dust removal at the borehole opening of a coal seam in-seam drilling operation, providing the aforementioned borehole opening dust removal device, involves drilling a coal seam in-seam borehole with a diameter of d1. When the drilling depth exceeds 1.5 to 2 times the length L1 of the expansion assembly 6, the drill bit 1 and drill rod 2 are removed, and drill bit 1 is replaced. The borehole opening is then enlarged to a length of L1 and a diameter of d2. The drill bit 1 and drill rod 2 are then removed, and the expansion assembly 6 is installed. Medium-pressure air 606 is injected into the bag 601 of the expansion assembly 6 through an underground medium-pressure air pipe until the expansion assembly 6 expands and is fixed within the borehole opening with a diameter of d2. The retractable dust removal device 9 is then connected to the water supply component 8. The water inlet 804 of the water supply component 8 is connected to the water inlet pipe of the drilling rig operating platform. During the drilling process, compressed air 3 enters through the drill rod 2. Coal slag 4, gas, and air 606 are discharged from the borehole and enter the retractable dust removal device 9 under the action of air pressure. Coal slag 4 is precipitated under the action of dust removal water sprayed from the water sprayer 903 of the retractable dust removal device 9 and is discharged from the slag outlet 905 of the retractable dust removal device 9. Air and gas are discharged through the external extraction pipeline connected to the air outlet 904 of the retractable dust removal device 9.

[0038] Example 1:

[0039] A dust removal device for coal seam borehole openings, referring to Figure 1 The system includes an expansion assembly 6, a water supply assembly 8, and a retractable dust removal device 9. The output end of the drilling rig 10 is fixedly connected to a drill rod 2, and the end of the drill rod 2 away from the drilling rig 10 is fixedly connected to a drill bit 1. The expansion assembly 6 and the retractable dust removal device 9 are both sleeved on the outside of the drill rod 2. One end of the expansion assembly 6 is connected to the retractable dust removal device 9, and the output end of the water supply assembly 8 is connected to the input end of the retractable dust removal device 9 to introduce dust removal water into the retractable dust removal device 9.

[0040] In this embodiment, refer to Figures 2-4 The expansion assembly 6 includes a bag 601, a steel cylinder 602 is fixedly inserted inside the bag 601, and an inflation port 603 is fixedly connected to one side of the bag 601 to facilitate inflation. A first gate valve 605 is threadedly connected to the inflation port 603 to control the amount of gas introduced.

[0041] In this embodiment, a plurality of hanging rings 604 are fixedly connected to one end of the bag 601 near the retractable dust removal device 9, and a plurality of hooks 901 corresponding to the hanging rings 604 are fixedly connected to the flexible bag 902, so as to facilitate connecting the bag 601 and the flexible bag 902.

[0042] In this embodiment, refer to Figure 6The retractable dust removal device 9 includes a flexible bag 902, and multiple water sprayers 903 are fixedly inserted inside the flexible bag 902 for spraying water to reduce dust. The end of the flexible bag 902 away from the expansion component 6 is provided with an air outlet 904 and a slag outlet 905 respectively. A connecting component 7 corresponding to the drill rod 2 is fixedly connected to the flexible bag 902 to facilitate the connection between the flexible bag 902 and the drill rod 2.

[0043] In this embodiment, refer to Figure 8 The connecting component 7 includes an installation sleeve 701. An elastic sleeve 702 is slidably inserted into the end of the installation sleeve 701 away from the flexible bag 902. Multiple sliders 703 are fixedly connected to the outer wall of the elastic sleeve 702. The inner wall of the installation sleeve 701 is provided with a groove corresponding to the slider 703. A slide rod 704 is fixedly connected in the groove. The slider 703 is provided with a sliding opening corresponding to the slide rod 704 for supporting the slider 703. A spring 705 is sleeved on the slide rod 704. The two ends of the spring 705 are fixedly connected to the slider 703 and the inner wall of the groove, respectively, to provide a certain elastic support for the slider 703. A sealing ring 706 is provided at the end of the elastic sleeve 702 away from the flexible bag 902 for sealing.

[0044] In this embodiment, refer to Figure 5 The water supply component 8 includes a high-pressure pipe 802. One end of the high-pressure pipe 802 is provided with a water inlet 804 for introducing clean water. A second gate valve 803 is threadedly connected to the water inlet 804. The bottom of the high-pressure pipe 802 is connected to the water sprayer 903 through multiple threaded joints 801 for introducing dust removal water into the retractable dust removal device 9.

[0045] In this embodiment, refer to Figure 7 The water sprayer 903 includes a main ring body 933, with a water inlet 931 at the top of the main ring body 933 and multiple nozzles 932 surrounding the edge of the main ring body 933 for spraying water to suppress dust.

[0046] In this embodiment, when drilling along the coal seam with a borehole diameter of d1 in the coal mine, after drilling for about 2m, the drill bit 1 and drill rod 2 are removed, the drill bit 1 is replaced, and the borehole opening is enlarged to a length of L1 and a diameter of d2. An expansion component 6 is installed, with its inner diameter not protruding from the borehole wall 5. The expansion component 6 consists of a cylinder 602 with an inner diameter of d3, a bag 601, a first gate valve 605, and an air inlet 603. Medium-pressure air is injected through the underground medium-pressure air pipe to fill the expansion component 6 until the borehole diameter d2 is filled, ensuring pressurization.

[0047] In this embodiment, a retractable dust removal device 9 is installed, and a hook 901 is hung on the hanging ring 604 of the expansion component 6; the retractable dust removal device 9 and the water supply component 8 are connected, and the threaded connector 801 is connected to the connector of the water sprayer 903. The threaded connector 801 is rotated and tightened to prevent water leakage, and the water inlet 804 is connected to the water inlet pipe of the operating table.

[0048] In this embodiment, during the drilling process, medium-pressure air enters through the drill rod 2. After the drill bit 1 breaks the coal body, coal slag 4, gas, and air are formed. Under the action of compressed air, the coal slag 4, gas, and air are discharged from the borehole and enter the retractable dust removal device 9. The coal slag 4 settles under the action of dust removal water and is discharged from the slag outlet 905. The air and gas are discharged from the external extraction pipeline connected to the air outlet 904. The dust removal water enters the high-pressure pipe 802 from the water inlet 804, enters the water sprayer 903 through the high-pressure pipe 802, and is sprayed out from the nozzle 932 through the main ring body 933 and enters the internal space of the retractable dust removal device.

[0049] In this embodiment, the expansion component 6 allows for inflation, filling the borehole d2 completely to ensure pressurization. The retractable dust removal device 9 can be connected to the drill rod 2 via the connecting component 7. Dust removal water can be introduced via the water supply component 8. This invention employs modular assembly, with internal expansion for fixation, and can directly utilize medium-pressure air from underground coal mines as power. The retractable dust removal device 9, as the core component, adopts a flexible and foldable structure, significantly reducing operating space and weight compared to existing technologies. Furthermore, this invention has lower material requirements, lower cost, and lower manufacturing difficulty, giving it a greater market advantage.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A dust removal device for the borehole opening of a coal seam along the seam, characterized in that: It includes a retractable dust removal device (9), which includes a flexible bag (902), a plurality of water sprayers (903) installed inside the flexible bag (902), and an air outlet (904) and a slag outlet (905) respectively on the upper and lower sides of the flexible bag (902). The retractable dust removal device (9) is detachably connected to the expansion component (6) at one end near the borehole opening by means of hooking or plugging. The expansion component (6) includes a cylinder (602) with an inner diameter larger than the outer diameter of the drill rod and a bag (601) arranged around the cylinder (602). The bag (601) is provided with an air inlet (603) to inject fluid into the bag through the air inlet (603) to achieve expansion and fixation of the expansion component. The retractable dust removal device (9) has a connecting component (7) at the end away from the borehole opening to achieve a dynamic sealing connection with the drill rod (2); The connecting component (7) includes a mounting sleeve (701). An elastic sleeve (702) is provided on the inner side of the end of the mounting sleeve (701) away from the flexible bag (902). The elastic sleeve (702) includes a conical section and a cylindrical section connected to the large end of the conical section. The cylindrical section is located at the end of the conical section away from the flexible bag (902). Multiple sliders (703) are fixedly connected to the outer wall of the elastic sleeve (702) corresponding to the conical section. A groove corresponding to the position of the slider (703) is provided on the inner wall of the mounting sleeve (701). A slide rod (704) is arranged parallel to the axial direction of the elastic sleeve in the groove. A sliding opening matching the slide rod (704) is provided on the slider (703). A spring (705) is sleeved on the slide rod (704) to make the elastic sleeve (702) fit with the drill rod. The two ends of the spring (705) are respectively connected to the slider (703) and the inner wall of the groove.

2. The dust removal device for coal seam borehole openings according to claim 1, characterized in that: A sealing ring (706) is provided at the end of the elastic sleeve (702) away from the flexible bag (902).

3. The dust removal device for coal seam borehole openings according to claim 1, characterized in that: The water sprayer (903) includes a main ring body (933), with a water inlet (931) at the top of the main ring body (933) and multiple nozzles (932) surrounding the edge of the main ring body (933).

4. The dust removal device for coal seam borehole openings according to claim 1, characterized in that: It also includes a water supply assembly (8) to supply water to the water sprayer (903). The water supply assembly (8) includes a high-pressure pipe (802), one end of which is provided with an inlet (804). The lower side of the high-pressure pipe (802) is provided with branch pipes in the same number as the number of water sprayers. The branch pipes are provided with connectors (801) for detachable connection with the water sprayer (903). A second gate valve (803) is provided at the inlet (804).

5. A dust removal device for coal seam borehole openings according to claim 4, characterized in that: The air inlet (603) can be connected to the downhole medium-pressure air pipe to inject medium-pressure air into the bag (601) through the downhole medium-pressure air pipe; a first gate valve (605) is provided at the air inlet (603).

6. A dust removal device for coal seam borehole openings according to claim 1, characterized in that: The expansion component (6) and the retractable dust removal device (9) are connected by a hook and ring structure. The hook and ring structure includes multiple rings (604) fixedly connected to one end of the bag (601) near the retractable dust removal device (9), and multiple hooks (901) fixedly connected to the flexible bag (902) and matched with the rings (604).

7. A dust removal device for coal seam borehole openings according to claim 5, characterized in that: The inlet (804) of the water supply assembly (8) can be connected to the water inlet pipe of the drilling rig operating table to supply water to the water supply assembly (8) through the water inlet pipe of the drilling rig operating table.

8. A method for dust removal at the orifice of a coal seam borehole, characterized in that: The orifice dust removal device as described in claim 7 is provided. When drilling a coal seam with a borehole diameter of d1, after the drilling depth is greater than 1.5 to 2 times the length L1 of the cylinder (602) of the expansion component (6), the drill bit (1) and drill rod (2) are removed, the drill bit (1) is replaced, and the borehole opening is enlarged until the hole length is L1 and the hole diameter is d2. Then the drill bit and drill rod (2) are removed, the expansion component (6) is installed, and medium-pressure air is injected into the bag (601) of the expansion component (6) through the underground medium-pressure air pipe until the expansion component (6) expands and is fixed in the borehole opening with a hole diameter of d2. Then the telescopic dust removal device is connected. The retractable dust removal device (9) is connected to the water supply component (8). The water inlet (804) of the water supply component (8) is connected to the water inlet pipe of the drilling rig operating platform. During the drilling process, compressed air enters through the drill rod (2). Under the action of air pressure, coal slag (4), gas and air are discharged from the borehole and enter the retractable dust removal device (9). The coal slag (4) settles under the action of dust removal water sprayed from the water sprayer (903) of the retractable dust removal device (9) and is discharged from the slag outlet (905) of the retractable dust removal device (9). Air and gas are discharged through the external extraction pipeline connected to the air outlet (904) of the retractable dust removal device (9).

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