Trenchless multi-stage pipe cleaning device and method combining artificial tornado and dagger-like mechanical sand

Abstract

A trenchless multi-stage pipe cleaning device and method combining an artificial tornado and dagger-like mechanical sand is provided. The trenchless multi-stage pipe cleaning device includes a primary pipe cleaning device and a secondary pipe cleaning device that are connected. An outer wall of the pipe cleaning device is provided with multiple air inlet joint pipes evenly distributed in a circumferential direction. The air inlet joint pipes are connected to an air compressor. Each of the air outlet joints is connected to a nozzle. The primary pipe cleaning device is connected to a vibrating screen. The trenchless multi-stage pipe cleaning device further includes a back-end sewage discharge device. In the trenchless multi-stage pipe cleaning method, the mechanical sand continuously scrape and collide with the inner wall of the cleaning target, so as to achieve a desired efficient trenchless water-free pipe cleaning effect.

Claims

1. A trenchless multi-stage pipe cleaning device combining an artificial tornado and dagger-like mechanical sand, comprising a front-end pipe cleaning device, wherein the front-end pipe cleaning device comprises a primary pipe cleaning device and a secondary pipe cleaning device; the primary pipe cleaning device comprises a primary right-end flange, a primary pipe cleaning device body and a primary left-end flange that are connected in sequence; multiple primary air inlet joint pipes are evenly distributed on an outer wall of the primary pipe cleaning device in a circumferential direction; and an axis of each of the primary air inlet joint pipes is diagonally intersecting with an axis of an inner chamber of the primary pipe cleaning device body in a same plane; the secondary pipe cleaning device comprises a secondary right-end flange, a secondary pipe cleaning device body and a secondary left-end flange that are connected in sequence; multiple secondary air inlet joint pipes are evenly distributed on an outer wall of the secondary pipe cleaning device in the circumferential direction; and an axis of each of the secondary air inlet joint pipes is diagonally tangent to a wall surface of an inner chamber of the secondary pipe cleaning device body; the primary left-end flange is connected to the secondary right-end flange, such that the primary pipe cleaning device is hermetically connected to the secondary pipe cleaning device; the primary air inlet joint pipes and the secondary air inlet joint pipes are hermetically connected to air outlet joints of a multi-channel directional valve, respectively; the multi-channel directional valve further comprises an air inlet joint and a hollow multi-channel directional valve body; the air inlet joint is connected to an air compressor; each of the air outlet joints is connected to a nozzle provided with an internal flow channel having a necked-down section; and each of the air outlet joints is provided with a shut-off valve for adjusting start, stop, and a flow rate of a compressed air flow; and the primary right-end flange of the primary pipe cleaning device is securely connected to an inlet flange of a feed pipe, and the feed pipe is connected to a discharge hole of a vibrating screen.

2. The trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand according to claim 1, further comprising a back-end sewage discharge device, wherein the front-end pipe cleaning device is mounted at one end of a cleaning target, and another end of the cleaning target is connected to the back-end sewage discharge device.

3. The trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand according to claim 1, wherein the primary air inlet joint pipes and the secondary air inlet joint pipes are adjustable joint pipes.

4. The trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand according to claim 3, wherein each of the adjustable joint pipes comprises a rigid sleeve and a crank-connecting angle changing mechanism; the crank-connecting angle changing mechanism comprises an S-shaped guide rail, a guide screw, an adjusting nut, and a telescopic guide rod; the S-shaped guide rail is provided with a guide groove; a bottom end of the guide screw is provided with a slider nested inside the guide groove; the guide screw is slidable freely along the guide groove in an S-shape; a top surface of the guide groove is provided with multiple limit holes at intervals; a lower part of the guide screw is provided with a limit base having screw holes on two sides; and when the guide screw slides to a suitable position, the limit base is securely connected to the limit holes through screws to fix the guide screw; a thread of the guide screw is connected to a thread of the adjusting nut; the adjusting nut is fixed at one end of the telescopic guide rod, and upper and lower sides of the adjusting nut are provided with fastening nuts; and the other end of the telescopic guide rod is hinged with the rigid sleeve; the rigid sleeve is coaxially sleeved outside a flexible corrugated pipe; and the flexible corrugated pipe is hermetically connected to each of the inner chamber of the primary pipe cleaning device body and the inner chamber of the secondary pipe cleaning device body wherein the plurality of S-shaped guide rails are evenly arranged on each of the outer wall of the primary pipe cleaning device and the outer wall of the secondary pipe cleaning device at intervals.

5. A trenchless multi-stage pipe cleaning method combining an artificial tornado and dagger-like mechanical sand, using the trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand according to claim 1, and comprising the following steps: mounting the front-end pipe cleaning device at one end of cleaning target, and connecting another end of the cleaning target to back-end sewage discharge device; opening shut-off valves of corresponding air outlet joints of the multi-channel directional valve according to a number of the primary air inlet joint pipes and a number of the secondary air inlet joint pipes; and starting the air compressor to deliver compressed air with a certain air pressure and air volume to the inner chamber of the primary pipe cleaning device body and the inner chamber of the secondary pipe cleaning device body through the multi-channel directional valve, the nozzles, the primary air inlet joint pipes, and the secondary air inlet joint pipes; starting the vibrating screen, and pouring mechanical sand particles onto a screen mesh of the vibrating screen; allowing sand particles filtered by the screen mesh to enter into the vibrating screen and slide along the feed pipe to a region adjacent to the primary right-end flange; sucking the sand particles by multiple streams of diagonally supplied high-speed air in the inner chamber of the primary pipe cleaning device body to form a primary gas-solid mixed flow, and allowing the primary gas-solid mixed flow to enter the inner chamber of the secondary pipe cleaning device body; forming the artificial tornado by multiple streams of diagonally tangential high-speed air entering the inner chamber of the secondary pipe cleaning device body; changing, by the artificial tornado, a movement trajectory of the primary gas-solid mixed flow entering the inner chamber of the secondary pipe cleaning device body into a spiral shape, tangential with an inner wall of the cleaning target; and driving the primary gas-solid mixed flow to move forward to form a secondary gas-solid mixed flow; wherein the sand particles continuously scrape and collide with the inner wall of the cleaning target, such that dirt attached to the inner wall of the cleaning target and accumulated on a bottom of the cleaning target is continuously removed; if the primary gas-solid mixed flow formed in the primary pipe cleaning device and the secondary gas-solid mixed flow formed in the secondary pipe cleaning device are found not sufficient to achieve a desired pipe cleaning effect, increasing the air pressure and air volume of the compressed air output by the air compressor; alternatively, adjusting inclination angles of the primary air inlet joint pipes and inclination angles of the secondary air inlet joint pipes, so as to adjust a movement state of the primary gas-solid mixed flow formed in the inner chamber of the primary pipe cleaning device body and a movement state of the secondary gas-solid mixed flow formed in the inner chamber of the secondary pipe cleaning device body, until the desired pipe cleaning effect is achieved; and discharging the removed dirt into the back-end sewage discharge device.

6. The trenchless multi-stage pipe cleaning method combining the artificial tornado and the dagger-like mechanical sand according to claim 5, wherein the trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand further comprises the back-end sewage discharge device.

7. The trenchless multi-stage pipe cleaning method combining the artificial tornado and the dagger-like mechanical sand according to claim 5, wherein in the trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand, the primary air inlet joint pipes and the secondary air inlet joint pipes are adjustable joint pipes.

8. The trenchless multi-stage pipe cleaning method combining the artificial tornado and the dagger-like mechanical sand according to claim 7, wherein in the trenchless multi-stage pipe cleaning device combining the artificial tornado and the dagger-like mechanical sand, each of the adjustable joint pipes comprises a rigid sleeve and a crank-connecting angle changing mechanism; the crank-connecting angle changing mechanism comprises an S-shaped guide rail, a guide screw, an adjusting nut, and a telescopic guide rod; the S-shaped guide rail is provided with a guide groove; a bottom end of the guide screw is provided with a slider nested inside the guide groove; the guide screw is slidable freely along the guide groove in an S-shape; a top surface of the guide groove is provided with multiple limit holes at intervals; a lower part of the guide screw is provided with a limit base having screw holes on two sides; and when the guide screw slides to a suitable position, the limit base is securely connected to the limit holes through screws to fix the guide screw; a thread of the guide screw is connected to a thread of the adjusting nut; the adjusting nut is fixed at one end of the telescopic guide rod, and upper and lower sides of the adjusting nut are provided with fastening nuts; and the other end of the telescopic guide rod is hinged with the rigid sleeve; the rigid sleeve is coaxially sleeved outside a flexible corrugated pipe; and the flexible corrugated pipe is hermetically connected to each of the inner chamber of the primary pipe cleaning device body and the inner chamber of the secondary pipe cleaning device body wherein the plurality of S-shaped guide rails are evenly arranged on each of the outer wall of the primary pipe cleaning device and the outer wall of the secondary pipe cleaning device at intervals.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1(a) is a schematic diagram showing a cleaning target with one end connected to a sewage storage tank and the other end connected to a pipe cleaning device;

(2) FIG. 1(b) is a schematic diagram showing a cleaning target with one end connected to a sewage suction truck and the other end connected to a pipe cleaning device;

(3) FIG. 1(c) is a schematic diagram showing a cleaning target with two ends connected to pipe cleaning devices, respectively;

(4) FIG. 2 is a structural diagram of a multi-channel directional valve according to the present disclosure;

(5) FIG. 3(a) is a schematic diagram showing a cleaning target with two threaded ends and an end flange of a pipe cleaning device;

(6) FIG. 3(b) is a schematic diagram showing a cleaning target with two flat ends and an end flange of a pipe cleaning device;

(7) FIG. 3(c) is an exploded view of a flat-end outlet flange;

(8) FIG. 3(d) is an overall structural diagram of the flat-end outlet flange;

(9) FIG. 4 is an overall structural diagram of a trenchless multi-stage pipe cleaning device combining an artificial tornado and dagger-like mechanical sand according to the present disclosure;

(10) FIG. 4(a) is an overall structural diagram of the trenchless multi-stage pipe cleaning device combining an artificial tornado and dagger-like mechanical sand according to the present disclosure;

(11) FIG. 4(b) is a perspective view of the trenchless multi-stage pipe cleaning device combining an artificial tornado and dagger-like mechanical sand according to the present disclosure;

(12) FIG. 4(c) is an exploded view of the trenchless multi-stage pipe cleaning device combining an artificial tornado and dagger-like mechanical sand according to the present disclosure;

(13) FIG. 5(a) is a perspective view of a primary pipe cleaning device according to the present disclosure;

(14) FIG. 5(b) is a section view of the primary pipe cleaning device according to the present disclosure;

(15) FIG. 6(a) is a perspective view of a secondary pipe cleaning device according to the present disclosure;

(16) FIG. 6(b) is an exploded view of the secondary pipe cleaning device according to the present disclosure;

(17) FIG. 7 is an overall structural diagram of a pipe cleaning device with an adjustable air supply angle according to the present disclosure;

(18) FIG. 8(a) is a perspective view of an adjustable joint pipe according to the present disclosure; and

(19) FIG. 8(b) is a perspective view of the adjustable joint pipe, with some components separated, according to the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(20) The specific technical solutions of the present disclosure are illustrated in conjunction with examples.

(21) As shown in FIGS. 1(a) to 1(c) and FIGS. 4(a) to 4(c), the present disclosure relates to a trenchless multi-stage pipe cleaning device combining an artificial tornado and dagger-like mechanical sand. The trenchless multi-stage pipe cleaning device includes vibrating screen 11, air compressor 12, multi-channel directional valve 13, sewage storage tank 14 or sewage suction truck 15, primary pipe cleaning device 21, secondary pipe cleaning device 22, S-shaped guide rails 31, guide screws 32, adjusting nuts 33, telescopic guide rods 34, rigid sleeves 36, flexible corrugated pipes 35, and other supporting accessory components.

(22) A target pipe (culvert) or drill string to be cleaned is referred to as cleaning target 01.

(23) The vibrating screen 11 is configured to screen sharp mechanical sand before the sharp mechanical sand is put into the pipe cleaning device for a pipe cleaning operation. The vibrating screen can effectively prevent clogging caused due to the concentration of a large amount of sand, and can ensure the supply of appropriate sand according to specifications. If the sand particles are too large, the suction force of the artificial tornado is required to be greater. However, during the pipe cleaning process, the artificial tornado will not easily carry the mechanical sand. The movement trajectory of the mechanical sand will be difficult to control, affecting the pipe cleaning effect. If the sand particles are too small, the scraping and collision effect on the inner wall of the cleaning target 01 is weak, and the cleaning effect is not desired. A screen mesh of the vibrating screen 11 allows particles with a size of 1-10 mm to pass through. The vibrating screen 11 is securely connected to primary right-end flange 211 of the primary pipe cleaning device 21 through feed pipe 110 and inlet flange 111.

(24) The multi-channel directional valve 13 is configured to distribute and deliver compressed air output from the air compressor 12 as needed. As shown in FIG. 2, the multi-channel directional valve mainly includes air inlet joint 130, hollow multi-channel directional valve body 131, and air outlet joints 132. Multiple primary air inlet joint pipes 213 and multiple secondary air inlet joint pipes 223 are evenly distributed on an outer wall of the primary pipe cleaning device and an outer wall of the secondary pipe cleaning device 21 and 22 in a circumferential direction, respectively. In order to increase the flow rate of the compressed air delivered to the multiple primary air inlet joint pipes and the multiple secondary air inlet joint pipes, nozzles 133 are securely connected at inlet ends of the primary air inlet joint pipes 213 and inlet ends of the secondary air inlet joint pipes 223, respectively. Each of the nozzles is provided with an internal flow channel having a necked-down section. The number of the air outlet joints 132 is greater than or equal to a sum of the number of the primary air inlet joint pipes 213 and the number of the secondary air inlet joint pipes 223. Each of the air outlet joints 132 is provided with a shut-off valve for adjusting start, stop, and a flow rate of the compressed air. The air outlet joint 132 is hermetically connected to the nozzle 133 through a high-pressure rubber hose. The air pressure and air volume of the compressed air provided by the air compressor 12 should meet the requirements of on-site working conditions. One or more parallel air compressors can be used. The number and connection method of the multi-channel directional valve 13 are flexibly adjustable according to the on-site working conditions.

(25) As shown in FIGS. 4(a) to 4(c) and FIGS. 5(a) to 5(b), the primary pipe cleaning device 21 mainly includes primary right-end flange 211, primary pipe cleaning device body 212, primary inlet joint pipes 213, and primary left-end flange 214. Multiple streams of the compressed air enter an inner chamber of the primary pipe cleaning device body 212 at a high speed through the multiple (3-8) primary air inlet joint pipes 213 evenly distributed on the outer wall of the primary pipe cleaning device in a circumferential direction. The multiple streams of the compressed air generate a suction force to suck the sharp mechanical sand that continuously slides into the feed pipe 110, forming a primary gas-solid (air-sand) mixed flow. A necked-down section (Laval nozzle) is located on a left side of the inner chamber of the primary pipe cleaning device body 212, before the primary air inlet joint pipes 213. When the air flow passes through the necked-down section, the flow rate of the air flow increases, thereby enhancing the suction effect of sand particles. The main purpose of the primary pipe cleaning device 21 is to continuously suck the sand particles to form the primary gas-solid mixed flow. Therefore, an axis of each of the primary air inlet joint pipes 213 is diagonally intersecting with an axis of the inner chamber of the primary pipe cleaning device body 212 in a same plane (with an angle of 20-70). However, no artificial tornado with spiral movement is generated here. To generate an artificial tornado in the inner chamber of the primary pipe cleaning device 21, it is necessary to adjust the angle between the primary air inlet joint pipe 213 and the inner chamber of the primary pipe cleaning device body 212.

(26) As shown in FIGS. 4(a) to 4(c) and FIGS. 6(a) to 6(b), the secondary pipe cleaning device 22 mainly includes secondary right-end flange 221, secondary pipe cleaning device body 222, secondary inlet joint pipes 223, and secondary left-end flange 224. The multiple (3-8) secondary air inlet joint pipes 223 are evenly distributed on an outer wall of the secondary pipe cleaning device in a circumferential direction. Multiple streams of the compressed air enter the inner chamber of the secondary pipe cleaning device body 222 at a high speed to generate an artificial tornado. The artificial tornado changes the movement trajectory of the primary gas-solid mixed flow formed by the primary pipe cleaning device 21, forming a secondary gas-solid mixed flow that moves forward in a spiral shape along an inner wall of the cleaning target 01. The artificial tornado also has a certain suction effect on the sand particles that slide from the vibrating screen 11. The sand particles in the secondary gas-solid mixed flow carried by the artificial tornado are like sharp daggers, continuously scraping and colliding with the inner wall of the cleaning target 01, thereby removing the dirt attached to the inner wall of the cleaning target and accumulated on the bottom of the cleaning target. The dirt is sucked and wrapped by the artificial tornado, and is discharged out of the cleaning target, thereby achieving the purpose of cleaning the inner wall of the pipe (culvert) or drill string. The main purpose of the secondary pipe cleaning device 22 is to form an artificial tornado with tangential and vertical movement and a strong suction force. Therefore, an axis of each of the secondary air inlet joint pipes 223 is diagonally tangent to a wall surface of the inner chamber of the secondary pipe cleaning device body 222 (with an angle of 25-75), causing the multiple streams of the compressed air tangentially entering the inner chamber of the secondary pipe cleaning device at a high speed to form an air flow (i.e., the artificial tornado) that is diagonally tangent to the inner wall of the secondary pipe cleaning device and moves forward in a spiral shape. If the power of the artificial tornado formed by one secondary pipe cleaning device 22 is insufficient and the secondary gas-solid mixed flow formed is not sufficient to achieve a desired pipe cleaning effect, more than one secondary pipe cleaning device 22 can be connected in series to enhance the power of the artificial tornado.

(27) As shown in FIG. 7, the primary air inlet joint pipes 213 and the secondary air inlet joint pipes 223 are adjustable joint pipes. Each of the adjustable joint pipes is provided with an angle-adjustable structure. The angle-adjustable structure includes flexible corrugated pipe 35 and rigid sleeve 36 coaxially sleeved outside the flexible corrugated pipe. The S-shaped guide rail 31, the guide screw 32, the adjusting nut 33, and the telescopic guide rod 34 form a crank-connecting angle changing mechanism. As shown in FIGS. 8(a) to 8(b), specifically, the S-shaped guide rails 31 are evenly arranged on each of the outer wall of the primary pipe cleaning device 21 and the outer wall of the secondary pipe cleaning device 22 at intervals, respectively. The S-shaped guide rail 31 can be fixed to the outer wall of the pipe cleaning device through a screw or strong adhesive. A bottom end of the guide screw 32 is provided with a slider nested inside the guide groove 311. The guide screw 32 is freely slidable along the guide groove 311 in an S-shape. Atop surface of guide groove 311 is provided with multiple limit holes 312 at intervals. A lower part of the guide screw 32 is provided with a limit base 321 having screw holes on two sides. When the guide screw 32 slides to a suitable position, the limit base 321 can be securely connected to the limit holes 312 through screws to fix the guide screw 32. The adjusting nut 33 is freely rotatable up and down along a thread of the guide screw 32. One end of the telescopic guide rod 34 is securely connected to a middle part of the adjusting nut 33. When the adjusting nut 33 is rotated to a suitable position, the adjusting nut can be tightened by fastening nuts 331 provided on two sides of the adjusting nut. The other end of the telescopic guide rod 34 is hinged with the rigid sleeve 36. The rigid sleeve 36 is coaxially sleeved outside the flexible corrugated pipe 35. The flexible corrugated pipe 35 is hermetically connected to each of the inner chamber of the primary pipe cleaning device body 212 and the inner chamber of the secondary pipe cleaning device body 222. By adjusting the length of the telescopic guide rod 34 and the positions of the guide screw 32 and the adjusting nut 33, the angle of the rigid sleeve 36 can be adjusted, thereby adjusting an inclination angle of the flexible corrugated pipe 35.

(28) The joint of the actual cleaning target 01 is not a fixed-type joint, and is usually a flanged, threaded, or flat-end joint. The joint type of the outlet flange 23 connected to the end of the cleaning target 01 can be flexibly selected according to the actual working conditions. As shown in FIG. 3(a), if the joint of the cleaning target 01 is a flanged joint, the secondary left-end flange 224 can be directly used. If the joint of the cleaning target 01 is a threaded joint, a threaded outlet flange 231 with a threaded joint on one side can be used. As shown in FIGS. 3(b), 3(c), and 3(d), if the joint of the cleaning target 01 is a flat-end joint, a flat-end outlet flange 232 with clamping groove 2321, positioning hole 2322, screw hole 2323, and expansion seal ring 2324 can be used. The expansion seal ring 2324 is made of rubber and can be inflated to expand or deflated to contract through inflation valve 2325. The expansion seal ring 2324 is nested in the clamping groove 2321, and the inflation valve 2325 of the expansion seal ring 2324 extends downwards from the positioning hole 2322. In order to facilitate the connection with the end of flat-joint cleaning target 01, the expansion sealing ring 2324 is initially not inflated but is in a contracting state. Flat-end outlet flange 232 with a suitable specification is nested in the flat-joint of the cleaning target 01. A screw passes through the screw hole 2323 and is securely connected to the inner wall of the cleaning target 01. A small air compressor is used to inflate the expansion seal ring 2324 through the inflation valve 2325 to make the expansion seal ring tightly fit with the inner wall of the cleaning target 01, thereby achieving the purpose of secure connection.

(29) Each two flanges are connected together by bolt 25.

(30) When it is necessary to perform in-situ trenchless pipe cleaning on the interior of an existing underground pipe (culvert) that has been in use for a certain period of time, or to clean the interior of a drill string after a drilling operation is completed, a first step is to select a suitable pipe cleaning device based on the specification, joint type, and internal dirt attachment/accumulation state of the cleaning target 01.

(31) The components of each part are hermetically connected according to the actual working conditions on site, ensuring that there is no air leakage at the pipes and joints. According to the number of the primary air inlet joint pipes 213 and the secondary air inlet joint pipes 223, shut-off valves of the corresponding air outlet joints 132 of the multi-channel directional valve 13 is opened. The air compressor 12 is started to deliver compressed air with a certain air pressure and air volume to the inner chamber of the primary pipe cleaning device body 212 and the inner chamber of the secondary pipe cleaning device body 222 through the multi-channel directional valve 13, the multiple high-pressure rubber hoses, the multiple nozzles 133, the primary air inlet joint pipes 213, and the secondary air inlet joint pipes 223. If the pipe cleaning on-site conditions permit, the mechanical sand can be one with required specifications directly purchased from the building materials market, or can be prepared by crushing large stones or construction solid waste to the required specifications through a rock crusher. The vibrating screen 11 is started, and the sharp mechanical sand is slowly poured onto a screen mesh of the vibrating screen 11. After being filtered by the screen mesh, sand particles with a size of 1-10 mm enter the vibrating screen 11 and slide along the feed pipe 110 to a region adjacent to the primary right-end flange 211. The sand particles are sucked by multiple streams of diagonally supplied high-speed air in the inner chamber of the primary pipe cleaning device body 212, forming a primary gas-solid mixed flow, and are carried to the inner chamber of the secondary pipe cleaning device body 222. Multiple streams of diagonally tangential high-speed air enter the inner chamber of the secondary pipe cleaning device body 222 to form an artificial tornado. The artificial tornado changes the movement trajectory of the primary gas-solid mixed flow entering the inner chamber of the secondary pipe cleaning device body 222 into a spiral shape, tangential with the inner wall of the cleaning target 01, and drives the primary gas-solid mixed flow to move forward, forming a secondary gas-solid mixed flow. During this process, the sand particles continuously scrape and collide with the inner wall of the cleaning target 01. The sand particles are like sharp daggers, allowing the dirt attached to the inner wall of the cleaning target and accumulated on the bottom of the cleaning target to be continuously peeled off.

(32) As shown in FIG. 1(a), if the outlet end of the cleaning target 01 is connected to the sewage storage tank 14, the dirt sucked and carried by the artificial tornado is discharged into the sewage storage tank 14 along with the secondary gas-solid mixed flow. As shown in FIG. 1(b), if the outlet end of the cleaning target 01 is connected to the sewage suction truck 15, the dirt sucked and carried by the artificial tornado is mixed with the secondary gas-solid mixed flow, and is discharged into the sewage suction truck 15. In this case, the dirt is also subjected to the suction force of the sewage suction truck 15. As shown in FIG. 1(c), if the outlet end of the cleaning target 01 is connected to the primary pipe cleaning device 21 and the secondary pipe cleaning device 22, the dirt is discharged to the sewage storage tank 14 or the sewage suction truck 15 under the suction action of double artificial tornados.

(33) During the pipe cleaning process, if it is found that the primary gas-solid mixed flow formed in the primary pipe cleaning device 21 and the secondary gas-solid mixed flow formed in the secondary pipe cleaning device 22 cannot achieve a desired pipe cleaning effect, the air pressure and air volume of the compressed air output by the air compressor should be increased. In addition, the fixed-type primary air inlet joint pipes 213 and the fixed-type secondary air inlet joint pipes 223 can be transformed into an angle-adjustable structure. That is, the positions of the guide screws 32, the adjusting nuts 33, the telescopic guide rods 34, the flexible corrugated pipes 35, and the rigid sleeves 36 are adjusted in a reasonable manner. Thus, the incoming states of the multiple streams of high-speed air entering the inner chamber of the primary pipe cleaning device body 212 through the primary air inlet joint pipes 213 and the inner chamber of the secondary pipe cleaning device body 222 through the secondary air inlet joint pipes 223 are adjusted. In this way, the movement state of the primary gas-solid mixed flow generated in the inner chamber of the primary pipe cleaning device body 212 and the movement state of the secondary gas-solid mixed flow generated in the secondary pipe cleaning device body 222 can be adjusted. All these attempts can achieve the desired pipe cleaning effect.

(34) After the pipe cleaning operation is completed, a closed-circuit television (CCTV) pipe detection robot (system) can be placed into the cleaning target 01 to check the condition of the inner wall of the cleaning target 01. When it is confirmed that the cleaning effect is acceptable, various components can be removed, and the on-site environment can be restored.