Underground coal gasification ash layer stripping device

Abstract

The invention discloses an underground coal gasification ash layer stripping device, and relates to the technical field of underground coal gasification ash layer stripping. The execution unit comprises a fixing disc, a gun barrel, a propelling assembly and a stripping assembly. According to the device, the transmission unit is controlled on the ground to drive the gun barrel to rotate, the spray head can rotate in the horizontal plane, and the circumferential cleaning blind area of a channel ash layer is eliminated. And meanwhile, the propelling assembly can control stretching and retracting of the spray head, so that the spray head can adapt to channels with different diameters and keep the optimal spraying distance, and the device can be flexibly attached to irregular channels. Secondly, uniform distribution and stable pressure of a high-pressure medium can be ensured by a flow dividing cavity arranged in the spray head; the spiral flow deflector in each injection pipe converts high-voltage direct flow into high-speed rotational flow to generate strong shear stress, so that a compact ash layer with strong adhesive force is efficiently crushed and stripped.

Description

Technical Field

[0001] This invention relates to underground coal gasification ash layer stripping technology, and more particularly to an underground coal gasification ash layer stripping device. Background Technology

[0002] During underground coal gasification, the combustion and gasification of coal produces a large amount of coal ash, which easily adheres to the inner wall of the gasification channel, forming an ash layer. As the ash layer thickens, it reduces the efficiency of the gasification reaction, leading to a decrease in gas production. In severe cases, it can block the gasification channel, causing the gasification process to be interrupted. Therefore, it is necessary to regularly and effectively clean the ash layer from the inner wall of the gasification channel.

[0003] Currently, the commonly used cleaning method employs high-pressure gas jetting devices, which generally consist of three parts: a high-pressure gas source, a delivery pipeline, and nozzles. However, this technology has significant drawbacks when practically applied to underground gasification channels: First, the jetting direction is fixed, while the underground gasification channel has a complex geometry and many bends. Therefore, conventional jetting methods inevitably leave a large number of blind spots and dead angles, resulting in poor cleaning effects. Second, traditional direct-flow jetting methods have very limited ability to remove dense ash layers with extremely strong adhesion. This is because the high-speed airflow easily diffuses after impacting the wall, so most of its kinetic energy cannot be effectively transferred to the bottom of the sediment. The impact energy utilization rate is extremely low, so repeated flushing is often required to achieve an acceptable cleaning effect. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is: the traditional DC jetting method has limited ability to peel off dense ash layers with strong adhesion, low impact energy utilization, and often requires repeated rinsing, which is time-consuming and energy-intensive.

[0005] The above-mentioned technical problems are solved by the following technical solution: The present invention proposes an underground coal gasification ash layer stripping device, which includes a drive unit including a drive component and an output shaft that is transmissionally connected to the drive component; The execution unit is located on one side of the output shaft and includes a fixed plate, a barrel connected to the axis of the fixed plate, a propulsion assembly fixed to the inside of the barrel, and a stripping assembly located at the front end of the propulsion assembly. A transmission unit, located between the drive unit and the execution unit, is used to transmit the rotational motion of the output shaft to the barrel, so as to drive the barrel and the stripping assembly to rotate around the axis of the barrel. The detection unit is used to detect the rotation angle of the barrel or the stripping assembly.

[0006] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the transmission unit includes a first direction output component and a second direction output component that mesh with each other, and a housing for accommodating the first direction output component and the second direction output component; The first directional output component is fixed to the end of the output shaft, and the second directional output component is fixedly sleeved on the end of the fixed disk shaft.

[0007] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the gun barrel is provided with an independent first channel and a second channel through one end near the fixed plate; The first channel is connected to the propulsion component and is used to provide a driving medium to the propulsion component; The second channel communicates with the inner cavity formed inside the barrel and is used to deliver the stripping working medium to the stripping assembly.

[0008] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the stripping component includes an air blowing pipe fixedly connected to the propulsion component, and an air blowing element connected to the end of the air blowing pipe.

[0009] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the air blowing pipe includes a straight pipe section and a bent pipe section connected to the straight pipe section.

[0010] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the inlet hole of the straight pipe section near the side of the propulsion component, and the sealing plate fixedly sleeved on the outside of the straight pipe section.

[0011] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the propulsion assembly includes a cylinder communicating with the first channel and a piston rod connected to the cylinder.

[0012] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the air blowing component includes a connecting pipe connected to the air blowing pipe and a nozzle connected to the connecting pipe.

[0013] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the nozzle is a diversion nozzle, which has a diversion cavity and a plurality of injection pipes communicating with the diversion cavity. At least one of the jet pipes is provided with a spiral guide vane.

[0014] In a preferred embodiment of the underground coal gasification ash layer stripping device of the present invention: the detection unit includes an angle sensor connected to one side of the output shaft axis.

[0015] The beneficial effects of this invention are as follows: First, the device drives the gun barrel to rotate via a ground-controlled transmission unit, allowing the nozzle to rotate and spray clean the circumferential layer of ash, thereby eliminating blind spots in the circumferential cleaning of the ash layer in the channel. Simultaneously, the propulsion assembly controls the extension and retraction of the nozzle, enabling it to adapt to channels of different diameters and maintain the optimal spray distance. Second, the nozzle's built-in flow-dividing chamber ensures uniform distribution and stable pressure of the high-pressure medium; the spiral guide vanes within each spray tube convert high-pressure direct current into high-speed swirling flow, generating strong shear stress, thus achieving efficient breaking and peeling of dense, strongly adhered ash layers. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 A schematic diagram of the underground coal gasification ash layer stripping device of the present invention is shown. Figure 2 A partial cross-sectional structural schematic diagram of the transmission unit of the present invention is shown; Figure 3 A partial cross-sectional structural diagram of the execution unit of the present invention is shown; Figure 4 A full cross-sectional schematic diagram of the execution unit structure of the present invention is shown; Figure 5 An exploded half-section schematic diagram of the air blowing component structure of the present invention is shown. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0019] Reference Figures 1-5 This embodiment provides an underground coal gasification ash layer stripping device, including a drive unit 1 including a drive component 11 and an output shaft 12 that is drively connected to the drive component 11; The execution unit 2 is located on one side of the output shaft 12 and includes a fixed plate 21, a gun barrel 22 connected to the axis of the fixed plate 21, a propulsion assembly 23 fixed to the inside of the gun barrel 22, and a stripping assembly 24 located at the front end of the propulsion assembly 23. The transmission unit 3 is located between the drive unit 1 and the execution unit 2, and is used to transmit the rotational motion of the output shaft 12 to the barrel 22 to drive the barrel 22 and the stripping assembly 24 to rotate around the axis of the barrel 22. The detection unit 4 is used to detect the rotation angle of the barrel 22 or the stripping assembly 24.

[0020] In this embodiment, as Figures 1 to 3 As shown, its overall structure mainly includes a drive unit 1, an execution unit 2, a transmission unit 3, and a detection unit 4.

[0021] The drive unit 1 is mounted on a ground operating platform; it includes a drive component 11 as a power source, which is preferably a servo motor or a stepper motor to provide precise rotation control. The output end of the drive component 11 is connected to an output shaft 12, which is connected to the transmission unit 3.

[0022] Preferably, the execution unit 2 is lowered into the underground gasification channel to perform the actual ash stripping operation. It is installed at the end of the output shaft 12 and specifically includes: a disc-shaped fixing plate 21 for providing an installation reference and load-bearing capacity, which is fixedly installed in the inlet structure of the gasification channel, serving as the rotational support base for the entire execution unit 2. The barrel 22 is a hollow tubular component, its tail end rigidly connected to the axial position of the fixing plate 21. The main body of the barrel 22 extends axially into the gasification channel. The propulsion assembly 23 is fixedly installed inside the barrel 22, driving the stripping assembly 24 linearly along the axial direction of the barrel 22. The stripping assembly 24 is fixedly located at the front end of the propulsion assembly 23, facing the depth of the gasification channel. Driven by the propulsion assembly 23, it can move axially relative to the barrel 22 to adjust its distance from the channel wall. Preferably, the peeling component 24 can peel off the ash layer, and it can be a nozzle capable of spraying high-pressure fluid gas or liquid.

[0023] When it is necessary to clean the inner wall of a section of the vaporization channel, the drive unit 1's drive component 11 first actuates, driving the output shaft 12 to rotate. This rotational motion is transmitted through the transmission unit 3, converting it into torque that drives the barrel 22 in the execution unit 2 to rotate around its axis. The rotation of the barrel 22 causes the stripping assembly 24 at its front end to rotate circumferentially. During this process, the detection unit 4 monitors the rotation angle in real time and feeds the data back to the control system. Based on this, the operator or automatic program can precisely control the spray direction of the stripping assembly 24, aligning it with the wall area to be cleaned. After determining the direction, the stripping assembly 24 can be activated, such as by turning on the high-pressure medium for stripping operations. Simultaneously, the distance between the stripping assembly 24 and the wall can be finely adjusted using the propulsion component 23 to achieve the best cleaning effect.

[0024] Reference Figure 2 As an optional embodiment, in one embodiment provided by the present invention, the transmission unit 3 includes a first direction output member 31 and a second direction output member 32 that mesh with each other, and a housing 33 for accommodating the first direction output member 31 and the second direction output member 32; The first direction output component 31 is fixed to the end of the output shaft 12, and the second direction output component 32 is fixedly sleeved on the shaft end of the fixed disk 21.

[0025] In a preferred embodiment of this invention, such as Figure 2 As shown, the transmission unit 3 connects the drive unit 1 and the execution unit 2. Its function is to change the direction of the rotational motion output by the drive unit 1 and transmit it to the execution unit 2. Specifically, this unit includes a sealed housing 33, which is fixed at a specific position at the wellhead channel entrance by a bracket. The housing 33 houses a first-direction output component 31 and a second-direction output component 32. The first-direction output component 31 is fixedly installed at the end of the output shaft 12 of the drive unit 1 via a key connection or other means, and rotates with it. The second-direction output component 32 is fixedly sleeved on the rearward-extending shaft end of the fixed disk 21 of the execution unit 2. When the drive unit 11 is activated, power is transmitted through the output shaft 12 and the first-direction output component 31 to the second-direction output component 32, thereby driving the entire fixed disk 21 and its connected barrel 22 and stripping assembly 24 to rotate around the axis of the barrel 22. The housing 33 serves to protect the gears and provide a seal, preventing the intrusion of downhole dust and moisture.

[0026] Preferably, the transmission unit 3 is used to change the direction of power transmission and drive the fixed disk 21 to rotate. In one specific embodiment, such as Figure 2As shown, it includes a pair of meshing bevel gears, namely the driving bevel gear as the longitudinal output member 31 and the driven bevel gear as the lateral output member 32. It is understood that the transmission unit 3 can also employ other mechanisms capable of achieving the same function, such as worm gear pairs, cross-shaft helical gear pairs, universal joint mechanisms, etc. The angle sensor of the detection unit 4 can be connected to the rotating shaft of the lateral output member 32 to detect its rotation angle.

[0027] Reference Figure 3 and Figure 4 As an optional embodiment, in one embodiment provided by the present invention, the barrel 22 near the fixed plate 21 has an independent first channel 221 and a second channel 222. The first channel 221 is connected to the propulsion component 23 and is used to provide the propulsion component 23 with a driving medium; The second channel 222 communicates with the inner cavity 223 formed inside the barrel 22 and is used to deliver the stripping working medium to the stripping assembly 24.

[0028] Furthermore, the propulsion assembly 23 includes a cylinder 231 communicating with the first channel 221, and a piston rod 232 connected to the cylinder 231.

[0029] Furthermore, the stripping assembly 24 includes an air pipe 241 fixedly connected to the propulsion assembly 23, and an air blowing element 242 connected to the end of the air pipe 241.

[0030] Furthermore, the air blowing pipe 241 includes a straight pipe section 2411 and a bent pipe section 2412 connected to the straight pipe section 2411.

[0031] Furthermore, the straight pipe section 2411 has an inlet hole 51 on the side near the propulsion assembly 23, and a sealing plate 52 fixedly sleeved on the outside of the straight pipe section 2411.

[0032] In this embodiment, as Figure 3 and 4 As shown, at the end of the barrel 22 near the fixed plate 21, two independent first channels 221 and second channels 222 are drilled through it. The first channel 221 is connected to the pneumatic source of the propulsion assembly 23 via a pipe, specifically for supplying compressed air to the propulsion assembly 23. The second channel 222 directly communicates with a through-cavity 223 formed inside the barrel 22. This cavity 223 extends forward to accommodate the stripping assembly 24 and supplies it with a high-pressure stripping working gas medium.

[0033] like Figure 4As shown, the stripping assembly 24 includes an air blowing pipe 241 and an air blowing element 242. The rear end of the air blowing pipe 241 is threadedly fixedly connected to the piston rod 232 of the propulsion assembly 23, and can be pushed by it to move back and forth. The front end of the air blowing pipe 241 is threadedly connected to the air blowing element 242.

[0034] Specifically, the air blowing pipe 241 is integrally formed by a straight pipe section 2411 and a curved pipe section 2412. The straight pipe section 2411 is sealed and hinged within the inner cavity 223 of the barrel 22. A pair of symmetrical inlet holes 51 are located at the rear end of the straight pipe section 2411 near the propulsion assembly 23. These inlet holes 51 are positioned within the inner cavity 223 of the barrel 22 to receive compressed air from within the inner cavity 223. At least one sealing plate 52, which can be an O-ring, is fixedly fitted onto the outer circumference of the straight pipe section 2411 and fits tightly against the inner wall of the barrel 22. The sealing plate 52 not only prevents compressed air from escaping but also allows the air blowing pipe 241 to slide within the barrel 22. The curved pipe section 2412 is connected to the front end of the straight pipe section 2411, and its bending angle is typically 90°, allowing the medium injection direction to be perpendicular to the channel axis, impacting the dust layer on the side wall.

[0035] like Figure 4 As shown, the propulsion assembly 23 includes a cylinder 231 and a piston rod 232. The cylinder 231 is fixed inside the barrel 22, and its air inlet is connected to the first channel 221 on the barrel 22 via a pipe. The front end of the piston rod 232 is fixed to the rear end of the straight section 2411 of the air blowing pipe 241. When compressed air passes through... Figure 4 When the path shown is b, that is, when it enters the corresponding chamber of the cylinder 231 through the first channel 221, the piston rod 232 can be pushed to extend or retract, thereby driving the entire stripping assembly 24 to advance or retreat along the barrel 22 axially to adapt to the cleaning needs of ash layers of different depths.

[0036] When the device is in operation, the execution unit 2 is first lowered into the underground gas channel corresponding to the predetermined section; the drive unit 1 drives the output shaft 12 to rotate, which in turn drives the barrel 22 and the stripping assembly 24 of the execution unit 2 to rotate around their own central axis through the transmission unit 3; then the detection value of the detection unit 4 determines whether it is adjusted to the direction of the channel wall to be cleaned; next, the propulsion assembly 23 is started, causing the stripping assembly 24 to be pushed forward to a position a certain distance away from the ash layer; then the air pump is turned on to allow compressed air to pass through. Figure 4After entering the second channel 222, inner cavity 223, and air blowing pipe 241 in the barrel 22 via the central path a, it reaches each spray pipe 62 in the nozzle 2422 and forms a high-speed vortex at the position of the aforementioned channel. The vortex is ejected through the spray pipe 62, thus achieving a large spray force and strong impact force, knocking off the attached dust layer on the channel wall. The peeled-off dust is also discharged with the airflow. Finally, with the rotation angle and axial position adjustable in a timely manner, the entire inner wall of the channel in this area is cleaned.

[0037] In summary, this device drives the barrel 22 to rotate via the transmission unit 3, thereby enabling the nozzle 2422 to achieve 360° stepless rotation in the horizontal plane. This rotation alone allows the spray beam to cover the entire annular area centered on the barrel, fundamentally eliminating the circumferential blind spot caused by a fixed spray direction. Furthermore, by controlling the propulsion assembly 23, the nozzle 2422 can extend or retract. This allows the nozzle 2422 to adapt to channels of different diameters, ensuring it is always at the optimal spray distance.

[0038] Reference Figures 3-5 As an optional embodiment, in one embodiment provided by the present invention, the air blowing component 242 includes a connecting pipe 2421 connected to the air blowing pipe 241, and a nozzle 2422 connected to the connecting pipe 2421.

[0039] Furthermore, the nozzle 2422 is a split nozzle, which has a split cavity 61 and multiple spray pipes 62 connected to the split cavity 61 inside. At least one injection pipe 62 is provided with a spiral guide vane 63.

[0040] Furthermore, the detection unit 4 includes an angle sensor 41 connected to one side of the axis of the output shaft 12.

[0041] In this embodiment, as Figure 4 As shown, the air blowing component 242 mainly consists of two parts: a connecting pipe 2421 and a nozzle 2422. The two work together to convert the high-pressure medium into a high-efficiency stripping jet.

[0042] The connecting pipe 2421 connects the bend section 2412 of the air blowing pipe 241 and the nozzle 2422. One end of the connecting pipe 2421 is connected to the outlet end of the bend section 2412 by thread, and the other end is connected to the inlet end of the nozzle 2422 in the same way, so as to quickly replace the nozzle 2422 after wear.

[0043] Preferably, the 2422 nozzle is a split-flow nozzle, and its shape is roughly spherical, as shown in the figure below. Figure 5As shown, a relatively spacious flow-dividing chamber 61 is machined inside the nozzle 2422. This chamber serves as a space for media buffering and uniform distribution, and its inlet is connected to the connecting pipe 2421 to receive the high-pressure working medium from the rear. The shape of the flow-dividing chamber 61 can be spherical, allowing the medium to be smoothly guided to each injection pipe 62. Multiple injection pipes 62 are drilled in different directions on the circumferential wall of the flow-dividing chamber 61. These injection pipes 62 are evenly distributed; for example, an axial hole can be provided at the center of the nozzle end face, and multiple radial holes can be evenly distributed around the nozzle circumference to achieve omnidirectional coverage of the dust layer in front and to the sides. The diameter and number of injection pipes 62 are designed according to the required total flow rate and impact pressure.

[0044] A spiral guide vane 63 is fixedly embedded in the diameter of each injection pipe 62. This guide vane is spiral-shaped; when the high-pressure medium flows through the injection pipe 62, the spiral guide vane 63 forces the medium to flow along a spiral trajectory, thereby converting most of the medium's pressure energy into rotational kinetic energy, forming a high-speed pneumatic vortex with extremely strong shear force. Compared to ordinary direct current, this vortex can improve the peeling effect on the attached ash layer.

[0045] The spiral guide vane 63 guides the linear airflow from the jet pipe 62 along a spiral trajectory, generating a high-speed cyclone. This cyclone exhibits a three-layer enhanced stripping effect: first, the radial shear force generated by the rotation laterally scrapes the ash layer, destroying its adhesion structure; second, the radial diffusion flow formed after impacting the wall penetrates and overturns the cracks in the ash layer; and third, the low-pressure zone at the core of the cyclone rapidly entrains and removes the stripped ash. These three factors work synergistically to transform the cyclone from simple impact into a complex process of shearing, tearing, and removal, thereby rapidly stripping away the dense sintered ash layer.

[0046] Better, such as Figure 2 As shown, the angle sensor 41 is existing technology, used to accurately measure the real-time rotation angle of the barrel 22 or the stripping assembly 24. The angle sensor 41 is mounted on the first direction output component 31 of the transmission unit 3. Specifically, its detection shaft is coaxially connected to the first direction output component 31, located on one side of the axis of the first direction output component 31. The stator portion of the angle sensor 41 is fixed to the housing 33, and the rotor portion is rigidly connected to the shaft of the first direction output component 31. The signal cable attached to the sensor is led to the ground control console along the protective sleeve of the output shaft 12 or a separately laid cable conduit. The sensor transmits the detected angle signal, such as a digital pulse or analog voltage, to the control system in real time.

[0047] In summary, this device achieves uniform distribution and pressure stabilization of high-pressure medium through the built-in diversion cavity 61 of the nozzle 2422, expands the coverage of single-point spray by using the circumferential multi-hole arrangement, and converts DC into forced rotational motion along its spiral channel by the spiral guide vane 63 in the spray pipe 62, thereby generating strong shear stress and achieving rapid peeling of dense and strongly adhesive ash layers.

[0048] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. An underground coal gasification ash layer stripping device, characterized in that: include, The drive unit (1) includes a drive element (11) and an output shaft (12) that is connected to the drive element (11) in a transmission manner. The execution unit (2) is located on one side of the output shaft (12), and includes a fixed plate (21), a gun barrel (22) connected to the axis of the fixed plate (21), a propulsion assembly (23) fixed to the inside of the gun barrel (22), and a stripping assembly (24) located at the front end of the propulsion assembly (23). The transmission unit (3) is located between the drive unit (1) and the execution unit (2) for transmitting the rotational motion of the output shaft (12) to the barrel (22) to drive the barrel (22) and the stripping assembly (24) to rotate around the axis of the barrel (22); The detection unit (4) is used to detect the rotation angle of the barrel (22) or the stripping assembly (24).

2. The underground coal gasification ash layer stripping device according to claim 1, characterized in that: The transmission unit (3) includes a first direction output member (31) and a second direction output member (32) that mesh with each other, and a housing (33) for accommodating the first direction output member (31) and the second direction output member (32). The first directional output component (31) is fixed to the end of the output shaft (12), and the second directional output component (32) is fixedly sleeved on the shaft end of the fixed disk (21).

3. The underground coal gasification ash layer stripping device according to claim 1 or 2, characterized in that: The barrel (22) has an independent first channel (221) and a second channel (222) through one end near the fixed plate (21). The first channel (221) is connected to the propulsion component (23) and is used to provide a driving medium to the propulsion component (23); The second channel (222) communicates with the inner cavity (223) formed inside the barrel (22) and is used to deliver the stripping working medium to the stripping assembly (24).

4. The underground coal gasification ash layer stripping device according to claim 3, characterized in that: The stripping assembly (24) includes an air pipe (241) fixedly connected to the propulsion assembly (23) and an air blowing element (242) connected to the end of the air pipe (241).

5. The underground coal gasification ash layer stripping device according to claim 4, characterized in that: The air blowing pipe (241) includes a straight pipe section (2411) and a bent pipe section (2412) connected to the straight pipe section (2411).

6. The underground coal gasification ash layer stripping device according to claim 5, characterized in that: The straight pipe section (2411) has an inlet hole (51) on the side near the propulsion assembly (23), and a sealing plate (52) fixedly sleeved on the outside of the straight pipe section (2411).

7. The underground coal gasification ash layer stripping device according to claim 6, characterized in that: The propulsion assembly (23) includes a cylinder (231) communicating with the first channel (221) and a piston rod (232) connected to the cylinder (231).

8. The underground coal gasification ash layer stripping device according to claim 5, characterized in that: The air blowing component (242) includes a connecting pipe (2421) connected to the air blowing pipe (241) and a nozzle (2422) connected to the connecting pipe (2421).

9. The underground coal gasification ash layer stripping device according to claim 8, characterized in that: The nozzle (2422) is a split nozzle, which has a split cavity (61) and a plurality of spray pipes (62) communicating with the split cavity (61). At least one of the jet pipes (62) is provided with a spiral guide vane (63).

10. The underground coal gasification ash layer stripping device according to claim 1, characterized in that: The detection unit (4) includes an angle sensor (41) connected to one side of the axis of the output shaft (12).

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