Hydraulic fracturing jetting device

Abstract

The invention relates to the technical field of oil and gas field fracturing, in particular to a hydraulic fracturing jetting device. According to the hydraulic fracturing jetting device, a damaged jetting head can be rapidly replaced, obstacles in the moving direction of a pipeline can be detected and removed, and the fracturing operation progress is guaranteed. A hydraulic fracturing jetting device comprises a main liquid conveying pipe, an auxiliary liquid conveying pipe and the like, the main liquid conveying pipe is connected into a tailstock, a hole is formed in the right portion of the main liquid conveying pipe, a jetting base is connected to the right portion of the main liquid conveying pipe, and the auxiliary liquid conveying pipe is connected into the jetting base. The rotating controller controls the mounting cover to rotate through the rotating ring, drives the spraying nozzle to rotate and replaces the spraying nozzle, and cooperates with the trigger head to detect obstacles in the moving direction and trigger the obstacle removing spraying sleeve to spray water pressure, so that the damaged spraying head can be quickly replaced, and the working efficiency is improved. And obstacles in the moving direction of the pipeline can be detected and removed, and the effect of the fracturing operation process is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field fracturing technology, and in particular to a hydraulic fracturing jetting device. Background Technology

[0002] Hydraulic fracturing is a technology used to extract oil and gas resources. It involves injecting high-pressure water and a liquid with certain additives into the wellhead to create fractures and fracture networks in underground rocks.

[0003] Existing hydraulic fracturing jetting devices first inject a mixture of high-pressure water and additives into the ground through the wellhead to increase the fluid's fluidity in the formation. The fluid gradually increases the internal pressure of the formation, exceeding the rock's compressive strength, thus creating fractures. These fractures continue to expand, forming a fracture network and increasing the fracture range. Fine sand particles are then injected to keep the fractures expanding, thereby increasing the flow channels for oil and gas. However, the nozzles of existing devices are prone to damage due to the scouring effect of high-speed fluid and the need for long-term operation. Damaged nozzles affect fluid injection, and replacement is inconvenient as the nozzles are deep within the rock formation. Furthermore, existing nozzles typically have side fluid outlets, but not in the forward direction, making it difficult to remove obstacles encountered in the pores, which seriously affects the fracturing operation process.

[0004] Therefore, a hydraulic fracturing jetting device has been developed that can quickly replace damaged jetting heads and detect and remove obstacles in the direction of pipeline movement, thus ensuring the progress of fracturing operations. Summary of the Invention

[0005] To overcome the shortcomings of existing devices, such as the inconvenience of replacing damaged nozzles and the difficulty in clearing obstacles encountered during propulsion within the orifice, which seriously affects the fracturing operation process, this invention provides a hydraulic fracturing jetting device that can quickly replace damaged nozzles and detect and clear obstacles in the pipeline's movement direction, ensuring the smooth progress of the fracturing operation.

[0006] Technical solution: A hydraulic fracturing jetting device includes a main infusion pipe, a secondary infusion pipe, a tailstock, a jetting seat, a switching mechanism, and a clearing mechanism. The tailstock is internally connected to the main infusion pipe, which has a hole on its right side. The jetting seat is internally connected to the main infusion pipe, which has holes on both its left and right sides. The right side of the main infusion pipe is connected to the left side of the secondary infusion pipe. The jetting seat is equipped with a switching mechanism to ensure the jetting state, and the secondary infusion pipe is equipped with a clearing mechanism to remove obstacles in the direction of the infusion jetting.

[0007] Furthermore, it is particularly preferred that the switching mechanism includes a mounting cover, a nozzle, a rotation controller, and a rotating ring. The mounting cover is rotatably connected to the spray seat, and multiple nozzles are connected to the mounting cover. The rotation controller is connected to the left side of the auxiliary infusion tube, and the rotating ring is connected to the right side of the rotation controller. The rotating ring is connected to the mounting cover. The liquid in the main infusion tube is input into the spray seat, and then guided into the nozzle through the spray seat and sprayed out. When the nozzle that is spraying liquid is damaged, the rotation controller controls the rotating ring to rotate, which in turn rotates the mounting cover to control the movement of the nozzle, so that the spare nozzle can replace the damaged nozzle, thereby adapting to the requirements of long-term operation.

[0008] Furthermore, it is particularly preferred that the obstacle-clearing mechanism includes an obstacle-clearing spray sleeve, a trigger head, a connecting rod, a movable valve, and a spring. The obstacle-clearing spray sleeve is connected to the right side of the auxiliary infusion tube. The trigger head is slidably connected to the inner side of the right side of the auxiliary infusion tube. The connecting rod is connected to the left side of the trigger head. The movable valve is slidably connected to the left side of the auxiliary infusion tube. The movable valve is connected to the left side of the connecting rod. A spring is connected between the movable valve and the auxiliary infusion tube. When the trigger head touches an obstacle, it is squeezed and moves to the left. The movable valve moves to the left to compress the spring. The leftward movement of the movable valve allows the liquid in the spray seat to enter the auxiliary infusion tube and be introduced into the obstacle-clearing spray sleeve through the auxiliary infusion tube, thereby clearing obstacles in the direction of the infusion spray.

[0009] Furthermore, it is particularly preferred that the device also includes a stabilizing mechanism for the main and auxiliary infusion tubes to advance. The stabilizing mechanism includes a device base, an electric push rod, a supporting arc plate, and a locking protrusion. The main and auxiliary infusion tubes are each connected to a device base, and multiple electric push rods are connected to each device base. The extension end of each electric push rod is connected to a supporting arc plate. The right side of the device base is connected to a locking protrusion, which engages with the obstacle-clearing spray sleeve. The extension end of the electric push rod controls the supporting arc plate to unfold and contact the inner wall of the spray hole, thereby stabilizing the main and auxiliary infusion tubes to advance and blocking falling stones inside the spray hole, thus protecting the main and auxiliary infusion tubes.

[0010] Furthermore, it is particularly preferred that the device also includes a protective mechanism to prevent the cleaning spray sleeve from becoming clogged. The protective mechanism includes a protective cover, a fixed base, a flap valve, a torsion spring, and an electromagnetic block. The protective cover is connected to the cleaning spray sleeve. Multiple fixed bases are connected to the inner right side of the protective cover. A flap valve is rotatably connected to the side of the fixed bases that are close to each other. Multiple torsion springs are connected between each flap valve and the adjacent fixed base. An electromagnetic block is connected to the side of the fixed bases that are far apart from each other. When the liquid inside the cleaning spray sleeve is sprayed out, it impacts the flap valve, causing the flap valve to rotate and contact the adjacent electromagnetic block. The electromagnetic block attracts and fixes the flap valve, allowing the liquid to spray out continuously. After the cleaning is completed, the electromagnetic block is controlled to release the flap valve. Under the reset action of the torsion spring, the flap valve covers and protects the cleaning spray sleeve again.

[0011] In addition, it is particularly preferred that an isolation cover is included, with the right side of the mounting base connected to the isolation cover, which isolates and protects the location of the rotation controller to prevent damage to the rotation controller.

[0012] In addition, it is particularly preferred that the device also includes an extension frame, which is connected to the right side of the trigger head. The extension frame can expand the contact area of ​​the trigger head and improve the obstacle clearing accuracy.

[0013] Furthermore, it is particularly preferred that the extension frame has a fan-shaped structure, which can increase the contact area while adapting to the arc shape of the inner wall of the spray hole to improve obstacle clearing accuracy.

[0014] The present invention has the following advantages: 1. The present invention uses a rotating controller to control the installation cover to rotate through a rotating ring, thereby driving the nozzle to rotate and replace the nozzle. It also uses a trigger head to detect obstacles in the direction of movement and trigger the clearing spray sleeve to spray water pressure. This can achieve the rapid replacement of damaged nozzles and the detection and removal of obstacles in the direction of pipeline movement, ensuring the effectiveness of fracturing operations.

[0015] 2. The present invention controls the expansion of the support arc plate and its contact with the inner wall of the injection hole by the telescopic end of the electric push rod. This can stabilize the main infusion tube and the auxiliary infusion tube as they move forward and protect them from collision damage.

[0016] 3. The present invention uses a torsion spring and a flap valve to cover and protect the obstacle clearing spray sleeve, which can prevent the obstacle clearing spray sleeve from becoming blocked when it is not in operation. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0018] Figure 2 This is a three-dimensional structural cross-sectional view of the present invention.

[0019] Figure 3 This is a partial three-dimensional structural schematic diagram of the present invention.

[0020] Figure 4 This is a three-dimensional structural cross-sectional view of the switching mechanism and the obstacle clearing mechanism of the present invention.

[0021] Figure 5 This is a cross-sectional view of the switching mechanism of the present invention.

[0022] Figure 6 This is a three-dimensional structural cross-sectional view of the obstacle-clearing mechanism of the present invention.

[0023] Figure 7This is a three-dimensional structural diagram of the stabilizing mechanism of the present invention.

[0024] Figure 8 This is a three-dimensional structural cross-sectional view of the protection mechanism of this invention.

[0025] Figure 9 This is a three-dimensional structural diagram of the protection mechanism of the present invention.

[0026] Figure 10 This is a three-dimensional structural diagram of the isolation cover and extension frame of the present invention.

[0027] The meanings of the reference numerals in the diagram are as follows: 1: Main infusion tube, 11: Auxiliary infusion tube, 12: Tailstock, 13: Spray seat, 2: Switching mechanism, 20: Mounting cover, 21: Spray nozzle, 22: Rotation controller, 23: Rotating ring, 3: Obstacle clearing mechanism, 30: Obstacle clearing spray sleeve, 31: Trigger head, 32: Connecting rod, 33: Moving valve, 34: Spring, 4: Stabilizing mechanism, 40: Equipment base, 41: Electric push rod, 42: Support arc plate, 43: Snap-fit ​​protrusion, 5: Protection mechanism, 50: Protective cover, 51: Fixed base, 52: Flip valve, 53: Torsion spring, 54: Electromagnetic block, 6: Isolation cover, 7: Extension frame. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] A hydraulic fracturing jetting device, such as Figures 1-3 As shown, it includes a main infusion tube 1, a secondary infusion tube 11, a tailstock 12, a spray seat 13, a switching mechanism 2, and a clearing mechanism 3. The main infusion tube 1 is connected inside the tailstock 12. The main infusion tube 1 has a hole on its right side. The spray seat 13 is connected to the right side of the main infusion tube 1. The spray seat 13 has three spray holes. The secondary infusion tube 11 is connected inside the spray seat 13. The secondary infusion tube 11 has holes on both its left and right sides. The right side of the main infusion tube 1 is connected to the left side of the secondary infusion tube 11. The switching mechanism 2 is provided on the spray seat 13, and the clearing mechanism 3 is provided on the secondary infusion tube 11.

[0030] like Figure 1 , Figure 2 , Figure 4 and Figure 5As shown, the switching mechanism 2 includes a mounting cover 20, a spray nozzle 21, a rotation controller 22, and a rotating ring 23. The mounting cover 20 is rotatably connected to the spray seat 13, and six spray nozzles 21 are connected to the mounting cover 20. The rotation controller 22 is connected to the left side of the auxiliary infusion tube 11, and the rotating ring 23 is connected to the right side of the rotation controller 22. The rotating ring 23 is connected to the mounting cover 20.

[0031] like Figure 1 , Figure 2 , Figure 4 and Figure 6 As shown, the obstacle clearing mechanism 3 includes an obstacle clearing spray sleeve 30, a trigger head 31, a connecting rod 32, a moving valve 33, and a spring 34. The obstacle clearing spray sleeve 30 is connected to the right side of the auxiliary infusion tube 11. The trigger head 31 is slidably connected to the inner side of the right side of the auxiliary infusion tube 11. The connecting rod 32 is connected to the left side of the trigger head 31. The moving valve 33 is slidably connected to the left side of the auxiliary infusion tube 11. The moving valve 33 is connected to the left side of the connecting rod 32. A spring 34 is connected between the moving valve 33 and the auxiliary infusion tube 11.

[0032] like Figure 2 and Figure 10 As shown, it also includes an isolation cover 6, which is connected to the right side of the mounting base.

[0033] like Figure 1 , Figure 2 and Figure 10 As shown, it also includes an extension frame 7. The extension frame 7 is connected to the right side of the trigger head 31. The extension frame 7 has a fan-shaped structure, which can increase the contact area and adapt to the arc of the inner wall of the spray hole to improve the obstacle clearing accuracy.

[0034] In use, this invention first connects the main fluid delivery pipe 1 to the water injection pipe in the hydraulic fracturing device. During operation, the main fluid delivery pipe 1 is driven into the pore of the injection hole downhole through the water injection pipe. After reaching the fracturing position, fracturing fluid is introduced into the main fluid delivery pipe 1 through the water injection pipe, and then flows into the injection seat 13 through the main fluid delivery pipe 1. Afterward, it is introduced into the injection nozzle 21 through the injection seat 13 and ejected. The injection nozzle 21 continuously injects fracturing fluid, gradually increasing the pressure inside the formation until it exceeds the compressive strength of the rock, thus creating fractures. After the rock fractures, further fracturing fluid is injected. The fracturing fluid expands and extends further through the fractures, causing the fracture network to expand to a larger area. Then, the sand injection pipe in the hydraulic fracturing device injects sand into the fractures. Fine sand particles are injected into the fracture to keep it expanded, thereby increasing the flow path for oil and gas. Afterward, the injection is stopped, and the injection pressure is reduced to keep the fracture open, allowing oil and gas to flow out. During injection, the hydraulic fracturing jetting device uses high-pressure fluid, resulting in a high fluid velocity at the nozzle 21. This high-speed fluid impacts and erodes the surface of the nozzle 21, subjecting it to mechanical stress and erosion, making it prone to damage. Since the nozzle 21 needs to operate for extended periods, when the nozzle 21 is damaged, the rotating controller 22 controls the rotating ring 23 to rotate, causing the mounting cover 20 to rotate and move the nozzle 21, allowing a backup nozzle to be moved. The nozzle 21 replaces the damaged nozzle 21, thus adapting to the requirements of long-term operation. During fracturing operations, the isolation cover 6 can isolate and protect the location of the rotation controller 22, preventing damage. When the injection seat 13 encounters an obstacle while moving, the trigger head 31 touches the obstacle and is squeezed to the left. This movement is controlled by the connecting rod 32, causing the moving valve 33 to move to the left and compress the spring 34. The leftward movement of the moving valve 33 allows the liquid in the injection seat 13 to enter the auxiliary infusion pipe 11, which then guides it into the obstacle-clearing injection sleeve 30, thereby clearing obstacles in the direction of the infusion injection. After the obstacle is cleared, the spring 34 rebounds, causing... The moving valve 33 resets to the right, blocking the inlet hole of the auxiliary infusion pipe 11 and controlling the connecting rod 32 and trigger head 31 to reset in order to deal with the next obstacle interception. The extension frame 7 can expand the contact area of ​​the trigger head 31, improving the obstacle clearing identification and triggering accuracy. The rotation controller 22 controls the installation cover 20 to rotate through the rotating ring 23, driving the nozzle 21 to rotate and replace the nozzle 21. It also works with the trigger head 31 to detect obstacles in the direction of movement and trigger the obstacle clearing spray sleeve 30 to spray water pressure. This can achieve the rapid replacement of damaged nozzles and the detection and removal of obstacles in the direction of pipeline movement, ensuring the effectiveness of the fracturing operation.

[0035] like Figure 1 , Figure 2 and Figure 7 As shown, it also includes a stabilizing mechanism 4, which includes an equipment base 40, an electric push rod 41, a supporting arc plate 42, and a snap-fit ​​protrusion 43. The main infusion tube 1 and the auxiliary infusion tube 11 are both connected to the equipment base 40, and three electric push rods 41 are connected to the equipment base 40. The telescopic end of the electric push rod 41 is connected to the supporting arc plate 42. The right side of the equipment base 40 is connected to the snap-fit ​​protrusion 43, which snaps into the obstacle clearing spray sleeve 30.

[0036] Using the stabilizing mechanism 4 of the present invention, the main infusion tube 1 and the auxiliary infusion tube 11 can be stabilized and moved forward. The telescopic end of the electric push rod 41 controls the support arc plate 42 to unfold and contact the inner wall of the spray hole, thereby stabilizing the main infusion tube 1 and the auxiliary infusion tube 11 and blocking stones falling into the spray hole, thus protecting the main infusion tube 1 and the auxiliary infusion tube 11. By controlling the extension end of the electric push rod 41 to unfold the support arc plate 42 and contact the inner wall of the spray hole, the main infusion tube 1 and the auxiliary infusion tube 11 can be stabilized and moved forward, and the main infusion tube 1 and the auxiliary infusion tube 11 can be protected from collision damage.

[0037] like Figure 1 , Figure 2 , Figure 8 and Figure 9 As shown, it also includes a protection mechanism 5, which includes a protective cover 50, a fixed base 51, a flap valve 52, a torsion spring 53, and an electromagnetic block 54. The protective cover 50 is connected to the obstacle clearing spray sleeve 30. Six fixed bases 51 are connected to the inner right side of the protective cover 50. A flap valve 52 is rotatably connected to the side of the fixed bases 51 that are close to each other. Two torsion springs 53 are connected between each flap valve 52 and the adjacent fixed base 51. An electromagnetic block 54 is connected to the side of the fixed bases 51 that are far apart from each other.

[0038] Using the protective mechanism 5 of the present invention, the obstacle clearing spray sleeve 30 can be prevented from becoming contaminated and clogged. When the obstacle clearing spray sleeve 30 is not in operation, the torsion spring 53 and the flap valve 52 cooperate to cover and protect the obstacle clearing spray sleeve 30, preventing it from becoming contaminated and clogged. When liquid discharge is required, the liquid inside the obstacle clearing spray sleeve 30 is sprayed out and impacts the flap valve 52, causing the flap valve 52 to rotate and contact the adjacent electromagnetic block 54. The electromagnetic block 54 attracts and fixes the flap valve 52, allowing the liquid to be sprayed continuously. After the obstacle clearing is completed, the electromagnetic block 54 is controlled to release the flap valve 52. Under the reset action of the torsion spring 53, the flap valve 52 covers and protects the obstacle clearing spray sleeve 30 again. Through the above-mentioned operation of the torsion spring 53 and the flap valve 52 cooperating to cover and protect the obstacle clearing spray sleeve 30, the blockage problem of the obstacle clearing spray sleeve 30 when not in operation can be prevented.

[0039] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A hydraulic fracturing jetting apparatus comprising It has a main infusion tube (1), a secondary infusion tube (11), a tail seat (12), a jet seat (13), a switching mechanism (2), and a clearing mechanism (3). The main infusion tube (1) is connected inside the tail seat (12). The main infusion tube (1) has a hole on its right side. The jet seat (13) is connected to the right side of the main infusion tube (1). The secondary infusion tube (11) is connected inside the jet seat (13). The secondary infusion tube (11) has holes on both its left and right sides. The right side of the main infusion tube (1) is connected to the left side of the secondary infusion tube (11). The jet seat (13) is equipped with a switching mechanism (2) to ensure the jetting state. The secondary infusion tube (11) is equipped with a clearing mechanism (3) to clear obstacles in the direction of infusion jetting.

2. A hydraulic fracturing jetting apparatus as defined in claim 1, wherein, The switching mechanism (2) includes a mounting cover (20), a nozzle (21), a rotation controller (22), and a rotating ring (23). The mounting cover (20) is rotatably connected to the spray seat (13), and multiple nozzles (21) are connected to the mounting cover (20). The rotation controller (22) is connected to the left side of the auxiliary infusion pipe (11), and the rotating ring (23) is connected to the right side of the rotation controller (22). The rotating ring (23) is connected to the mounting cover (20). The liquid in the main infusion pipe (1) is input into the spray seat (13) and guided into the nozzle (21) through the spray seat (13) and sprayed out. When the nozzle (21) that is spraying liquid is damaged, the rotating ring (23) is controlled to rotate by the rotation controller (22), so that the mounting cover (20) rotates to control the nozzle (21) to move, so that the spare nozzle (21) replaces the damaged nozzle (21), thereby adapting to the requirements of long-term operation.

3. A hydraulic fracturing jetting apparatus as defined in claim 2, wherein, The obstacle clearing mechanism (3) includes an obstacle clearing spray sleeve (30), a trigger head (31), a connecting rod (32), a moving valve (33), and a spring (34). The obstacle clearing spray sleeve (30) is connected to the right side of the auxiliary infusion tube (11). The trigger head (31) is slidably connected to the inner side of the right side of the auxiliary infusion tube (11). The connecting rod (32) is connected to the left side of the trigger head (31). The moving valve (33) is slidably connected to the left side of the auxiliary infusion tube (11). The moving valve (33) is connected to the left side of the connecting rod (32). The moving valve (33) is connected to the left side of the connecting rod (32). A spring (34) is connected between the auxiliary infusion tubes (11). When the trigger head (31) touches the obstacle, it is squeezed and moves to the left. The moving valve (33) is controlled by the connecting rod (32) to move, so that the moving valve (33) moves to the left to compress the spring (34). The moving valve (33) moves to the left so that the liquid in the spray seat (13) can enter the auxiliary infusion tube (11) and be introduced into the obstacle clearing spray sleeve (30) through the auxiliary infusion tube (11), thereby clearing the obstacle in the direction of the infusion spray.

4. A hydraulic fracturing jetting apparatus as defined in claim 3, wherein, It also includes a stabilizing mechanism (4) for advancing the main infusion tube (1) and the auxiliary infusion tube (11). The stabilizing mechanism (4) includes a device base (40), an electric push rod (41), a support arc plate (42), and a snap-fit ​​protrusion (43). The main infusion tube (1) and the auxiliary infusion tube (11) are both connected to the device base (40). Multiple electric push rods (41) are connected to the device base (40). The telescopic ends of the electric push rods (41) are all connected to a support. The right side of the equipment base (40) of the support plate (42) is connected to the snap-fit ​​protrusion (43). The snap-fit ​​protrusion (43) snaps into the obstacle clearing spray sleeve (30). The extension end of the electric push rod (41) controls the support plate (42) to unfold and contact the inner wall of the spray hole, thereby stabilizing the main infusion pipe (1) and the auxiliary infusion pipe (11) to move forward and blocking the stones falling into the spray hole, thereby protecting the main infusion pipe (1) and the auxiliary infusion pipe (11).

5. A hydraulic fracturing jetting apparatus as defined in claim 4, wherein, It also includes a protective mechanism (5) to prevent the clearing spray sleeve (30) from being contaminated and clogged. The protective mechanism (5) includes a protective cover (50), a fixed seat (51), a flap valve (52), a torsion spring (53), and an electromagnetic block (54). The clearing spray sleeve (30) is connected to the protective cover (50). Multiple fixed seats (51) are connected to the inner right side of the protective cover (50). A flap valve (52) is rotatably connected to the side of the fixed seats (51) that are close to each other. Multiple torsion springs are connected between the flap valve (52) and the adjacent fixed seat (51). (53) Electromagnetic blocks (54) are connected to the opposite sides of the fixed base (51). When the liquid inside the obstacle clearing spray sleeve (30) is sprayed out, it impacts the flap valve (52), causing the flap valve (52) to rotate and contact the adjacent electromagnetic block (54). The electromagnetic block (54) attracts and fixes the flap valve (52), so that the liquid can be continuously sprayed out. After the obstacle clearing is completed, the electromagnetic block (54) is controlled to release the flap valve (52). Under the reset action of the torsion spring (53), the flap valve (52) covers and protects the obstacle clearing spray sleeve (30) again.

6. A hydraulic fracturing jetting apparatus as defined in claim 5, wherein, It also includes an isolation cover (6), which is connected to the right side of the mounting base. The isolation cover (6) isolates and protects the location of the rotation controller (22) to prevent damage to the rotation controller (22).

7. A hydraulic fracturing jetting apparatus as defined in claim 6, wherein, It also includes an extension frame (7), which is connected to the right side of the trigger head (31). The extension frame (7) can expand the contact area of ​​the trigger head (31) and improve the obstacle clearing accuracy.

8. A hydraulic fracturing jetting apparatus as defined in claim 7, wherein, The extension frame (7) has a fan-shaped structure, which can increase the contact area while adapting to the arc shape of the inner wall of the spray hole to improve the obstacle clearing accuracy.

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