Cleaning device and cleaning method for oxide skin on inner wall of heating surface pipe of power station boiler

Abstract

The invention relates to a power station boiler heating surface pipe inner wall oxide skin cleaning device and method. The power station boiler heating surface pipe inner wall oxide skin cleaning device comprises a moving assembly, a cutting assembly and a detecting assembly which are connected from top to bottom. The moving assembly comprises a through type lead screw motor, a lead screw and a centering pipe. The cutting assembly comprises a cutting motor, a motor disc, a driving gear, a transmission gear, a transmission gear ring, a rotating sleeve, an oil passing inner pipe, an oil passing outer pipe and a cutting cylinder. The detection assembly comprises a camera with a lighting function and a loading cylinder; according to the device, whether oxide skin exists on the inner wall of the heated surface pipe or not is judged through the detection assembly, the cutting assembly is used for cutting, and the moving assembly is used for driving the cutting assembly and the detection assembly to move axially. According to the method, the oxide skin is judged more accurately, and the maintenance cost can be reduced; the cleaning method is easy to operate and convenient to use, the maintenance efficiency is improved, and the maintenance period is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of cleaning the inner wall oxide scale of the heating surface pipes of power station boilers, and particularly relates to a device and a method for cleaning the inner wall oxide scale of the heating surface pipes of power station boilers. Background Art

[0002] The heating surface of a power station boiler is a pipe system composed of components such as water walls, superheaters, reheaters, and economizers. Its function is to absorb the heat released by fuel combustion and gradually heat the feed water into superheated steam for steam turbine power generation. The heating surface pipes are often made of ferritic steel materials. During the long-term use of the heating surface pipes of power station boilers, the inner wall is prone to generating oxide scale due to high-temperature oxidation. As the boiler temperature rises, the high-temperature oxidation phenomenon on the inner wall of the heating surface pipes intensifies. Especially for some units with deep peak shaving, due to long-term low-load operation, uneven burning in the furnace, low working fluid flow rate in the pipes, and poor hydrodynamic characteristics, they are more likely to experience overheating, accelerating the formation of oxide scale. The oxide scale will affect the heat transfer performance of the heating surface pipes, resulting in low working efficiency of the heating surface pipes. Moreover, over time, the thickness of the oxide scale continues to increase. When the thickness of the oxide scale exceeds the critical thickness, the oxide scale will flake off and accumulate at the turning points of the heating surface pipes, leading to overheating and tube rupture. The measures of the prior art to deal with the problem of the inner wall oxide scale of the heating surface pipes are to detect the thickness of the oxide scale according to relevant power standards. Once it is detected that the thickness of the oxide scale reaches the standard, the corresponding part of the heating surface pipes will be replaced on a large scale. The prior art has the following problems: 1. The oxide scale detection only detects specific positions, which may not necessarily conform to the actual situation of the entire heating surface pipe, and it is easy to cause mis-replacement of pipes; 2. The maintenance cost of large-scale pipe replacement is high, the maintenance period is long, resulting in a waste of a large amount of human and physical resources of power generation enterprises. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a device and a method for cleaning the inner wall oxide scale of the heating surface pipes of power station boilers.

[0004] The technical solution of the present invention is: A device for cleaning the inner wall oxide scale of the heating surface pipes of a power station boiler includes a moving component, a cutting component, and a detection component that are connected in sequence from top to bottom; the moving component is responsible for driving the cutting component and the detection component to move axially along the heating surface pipe; the cutting component is responsible for cutting the oxide scale on the inner wall of the heating surface pipe; the detection component is responsible for detecting the thickness of the oxide scale on the inner wall of the heating surface pipe;

[0005] The moving component includes a through-type lead screw motor, a lead screw, and a centering tube; the through-type lead screw motor is vertically arranged at the nozzle of the heating surface tube; the lead screw is matched with the through-type lead screw motor; the through-type lead screw motor outputs torque to drive the axial movement of the lead screw; the lower end of the lead screw is connected to the upper end of the centering tube; the axially moving lead screw drives the axial movement of the centering tube; at least three circumferentially distributed telescopic wheel mechanisms are arranged in the middle of the centering tube; the circumferentially distributed telescopic wheel mechanisms keep the centering tube in a centered state; the telescopic wheel mechanism includes a telescopic rod, a traveling wheel, an outer top spring, and a limit nut; the traveling wheel is rotatably connected to the outer end of the telescopic rod; the circumferentially distributed telescopic wheel mechanisms keep the centering tube in a centered state; the telescopic rod passes through the outer top spring, penetrates the centering tube, and is threadedly matched with the limit nut, so that the traveling wheel slides on the inner wall of the heating surface tube to provide guidance for the axial movement of the centering tube; the limit nut prevents the telescopic rod from coming out; a baffle is fixedly connected to the outer end of the telescopic rod; one end of the outer top spring abuts against the baffle, and the other end abuts against the outer wall of the centering tube; the outer top spring drives the traveling wheel to keep abutting against the inner wall of the heating surface tube;

[0006] The cutting component includes a cutting motor, a motor disk, a driving gear, a transmission gear, a transmission gear ring, a rotating sleeve, an inner oil-passing tube, an outer oil-passing tube, and a cutting cylinder;

[0007] The cutting motor is installed on the motor disk; the motor disk is respectively connected to the centering tube and the inner oil-passing tube; the output shaft of the cutting motor is coaxially fixedly connected with the driving gear; the cutting motor outputs torque to drive the driving gear to rotate; the transmission gear ring is sleeved outside the driving gear; the transmission gear is arranged between the driving gear and the transmission gear ring, leaving a gap between the transmission gear ring and the driving gear for the oil pipe and the wire to pass through; the transmission gear meshes with the driving gear and the transmission gear ring, so that the torque output by the cutting motor can be transmitted to the transmission gear ring; the transmission gear ring is connected to the outer oil-passing tube through the rotating sleeve to transmit the torque to the outer oil-passing tube; the cutting cylinder is radially fixed on the outer wall of the outer oil-passing tube; a cutting head is arranged at the end of the piston rod of the cutting cylinder; the piston rod extends outwards, and the cutting head abuts against the inner wall of the heating surface tube; the outer oil-passing tube rotates to drive the cutting head to cut the oxide scale; several oil-passing ports and an axial oil-passing cavity are arranged at the upper end of the inner oil-passing tube; the oil-passing ports are connected to the oil pipe to realize the passage of the oil circuit; several oil-passing ring grooves are axially evenly distributed on the outer wall of the inner oil-passing tube; the oil-passing ports, the oil-passing cavity, and the oil-passing ring grooves are connected in one-to-one correspondence to form the oil circuit route inside the inner oil-passing tube; sealing rings are arranged on both sides of the oil-passing ring grooves to seal the oil-passing ring grooves to prevent the oil circuits of the respective oil-passing ring grooves from interfering with each other and also ensure that the outer oil-passing tube can rotate relative to the inner oil-passing tube; the outer oil-passing tube is hermetically sleeved outside the lower end of the inner oil-passing tube to avoid oil leakage; an oil supply port corresponding to the oil-passing ring groove is arranged on the outer wall of the outer oil-passing tube; the oil supply port is connected to the cutting cylinder through a hose to supply oil to the cutting cylinder and realize the expansion and contraction of the piston rod;

[0008] The detection component includes an illumination camera and a loading cylinder; the loading cylinder is correspondingly arranged below the illumination camera; a hardness indenter is fixed on the piston rod of the loading cylinder; the loading cylinder drives the hardness indenter to press against the inner wall of the heating surface tube to form an indentation; the illumination camera takes a picture of the indentation; whether there is scale on the inner wall of the heating surface tube is judged by the size of the indentation to determine whether to use a cutting tool head for cutting; the oil pipe passes through the oil-passing inner tube and is communicated with the loading cylinder.

[0009] Preferably, most of the heating surface tubes are arranged vertically; the moving component further includes a mounting end plate; the mounting end plate is connected to the through-type lead screw motor by screw A and forms an integral body with the through-type lead screw motor; the mounting end plate is buckled on the pipe orifice of the heating surface tube; the through-type lead screw motor is also left outside the heating surface tube; the mounting end plate is provided with a radial groove A corresponding to the lead screw; the inner end of the radial groove A can allow the lead screw to pass through; the outer end of the radial groove A penetrates the edge of the mounting end plate to open a channel that can enter the inside of the heating surface tube, so as to facilitate the entry of the oil pipe or wire.

[0010] Preferably, the lower end of the lead screw is rotatably connected to the upper end of the centering tube, which can reduce the influence of the self-rotation of the lead screw on the axial movement stability of the cutting component and the detection component.

[0011] Preferably, an end ring sleeved on the lead screw is installed at the upper end of the centering tube; a clamping plate is fixedly connected to the lower end of the lead screw; a shaft clamp is also installed at the lower end of the lead screw; the end ring is arranged between the clamping plate and the shaft clamp to realize the rotational connection between the centering tube and the lead screw.

[0012] Furthermore, an arc-shaped connecting plate extending downward is provided at the outer edge of the end ring; screw B penetrates the arc-shaped connecting plate and is threadedly connected to the centering tube; in this way, the end ring and the centering tube are detachably connected, which is convenient for assembly.

[0013] Furthermore, the threaded end of screw B penetrates the tube wall of the centering tube and is located below the clamping plate; when the shaft clamp fails, the threaded end of screw B can limit the clamping plate to ensure that the lead screw can normally drive the cutting component and the detection component to move axially downward.

[0014] Preferably, a limit spring groove corresponding to the telescopic rod is provided on the outer wall of the middle part of the centering tube; the outer top spring abuts against the bottom of the limit spring groove; the bottom of the limit spring groove is a plane, which realizes effective contact with the outer top spring; the groove wall of the limit spring groove limits the outer top spring to prevent the outer top spring from bending sideways, ensuring that the elastic force of the outer top spring fully acts on the baffle plate and ensuring that the traveling wheels are in full contact with the inner wall of the heating surface tube.

[0015] Furthermore, the radial cross-section of the inner end of the telescopic rod is square; a square hole corresponding to the telescopic rod is provided at the bottom of the limit spring groove; the inner end of the telescopic rod is slidably matched with the square hole to realize the guidance of the radial expansion and contraction of the telescopic rod.

[0016] Preferably, the oil inlet is arranged on the side of the upper end of the inner oil pipe, saving axial space and making the structure more compact; the upper end of the oil cavity penetrates through the inner oil pipe; the oil cavity can be machined by drilling from the upper end of the inner oil pipe; a plug is installed at the upper port of the oil cavity to seal the upper end of the oil cavity.

[0017] Preferably, there are two cutting cylinders, which are respectively arranged at the upper and lower parts of the outer oil pipe; the cutting tool head on the piston rod of the upper cutting cylinder is a fine turning tool head for fine turning the inner wall of the heating surface pipe to remove the oxide scale; the cutting tool head on the piston rod of the lower cutting cylinder is a rough turning tool head for rough turning the inner wall of the heating surface pipe to remove the oxide scale.

[0018] Preferably, the device for cleaning the oxide scale on the inner wall of the heating surface pipe of a power station boiler further includes stud bolt A, stud bolt B, stud bolt C, large ring, and small disc; the upper end of the lighting camera is connected to the large ring; the loading cylinder is installed on the loading cylinder; stud bolt A connects the lower end of the centering pipe to the motor disc; stud bolt B connects the motor disc to the upper end of the inner oil pipe; the upper end of stud bolt C penetrates through the large ring and is threadedly connected to the lower end of the inner oil pipe; the outer diameter of the large ring > the inner diameter of the outer oil pipe; the lower end of stud bolt C is connected to the small disc; the detachable structure of the oxide scale cleaning device is realized through stud bolt A, stud bolt B, and stud bolt C, which is convenient for later maintenance and replacement.

[0019] Furthermore, the motor disc is provided with a radial groove B; the wires connected to the lighting camera and the oil pipes connected to the loading cylinder and the oil inlet pass through the radial groove B to reduce the wear of the wires and oil pipes on the heating surface pipe.

[0020] A cleaning method for the above-mentioned device for cleaning the oxide scale on the inner wall of the heating surface pipe of a power station boiler includes the following steps:

[0021] ① Install the oxide scale cleaning device onto the heating surface pipe

[0022] The loading cylinder, the detection component, the cutting component, and the centering pipe enter the inside of the heating surface pipe in sequence; when the centering pipe enters the heating surface pipe, first contract the telescopic rod towards the heating surface pipe, and then release the telescopic rod after the walking wheels enter the heating surface pipe; the telescopic rod is pushed outwards by the external spring; the walking wheels abut against the inner wall of the heating surface pipe; when the through-type lead screw motor base is at the upper end of the heating surface pipe, the cutting component and the detection component are centered with the centering pipe and are at the axial center position of the heating surface pipe;

[0023] ② The oxide scale cleaning device works

[0024] 2.1 Deliver hydraulic oil with a pressure of 9.8 N to the loading cylinder to extend the piston rod of the loading cylinder, make the hardness indenter abut against the inner wall of the heating surface pipe for a certain period of time to leave an indentation; retract the piston rod of the loading cylinder;

[0025] 2.2 Drive the lead screw shaft to move downward by a distance h1 through the through-type lead screw motor; h1 is the height difference between the lighting camera and the loading cylinder; the lighting camera also descends and just stays at the place opposite to the indentation to take a photo of the indentation.

[0026] 2.3 Judge whether there is scale on the inner wall of the heating surface tube according to the size of the indentation in the photo; if it is judged that there is scale, execute step 2.4; if it is judged that there is no scale, execute step 2.1.

[0027] 2.4 Deliver hydraulic oil to the cutting cylinder to make the cutting tool head abut against the inner wall of the heating surface tube; start the cutting motor to make the cutting cylinder rotate, and the cutting tool head cuts the inner wall of the heating surface tube; drive the lead screw shaft to move downward by a distance h2 through the through-type lead screw motor; h2 is the height difference between the cutting tool head and the lighting camera; retract the piston rod of the cutting cylinder; h1 and h2 are equivalent.

[0028] 2.5 Repeat step 2.1 until the detection component passes through the entire section of the heating surface tube.

[0029] The beneficial effects of the present invention are:

[0030] (1) The present invention judges whether there is scale on the inner wall of the heating surface tube through the detection component, uses the cutting component for cutting, and uses the moving component to drive the cutting component and the detection component to move axially. The judgment of the present invention on the scale is more accurate and can reduce the maintenance cost; generally, the hardness of the scale on the heating surface tube is much higher than that of the heating surface tube body. The loading cylinder of the detection component presses the hardness indenter against the inner wall of the heating surface tube; the indentation depth of the hardness indenter remaining on the heating surface tube body > the indentation depth of the hardness indenter remaining on the scale; what is reflected on the image obtained by the lighting camera is the size on the two-dimensional figure of the indentation, and the maximum diagonal dimension can be used as the index parameter of the indentation size; so when the diagonal dimension of the indentation obtained by the lighting camera is small to a certain extent, it can be judged that the position where the hardness indenter abuts is the scale, otherwise it is determined that the position where the hardness indenter abuts is the heating surface tube body; according to the judgment result, assist the cutting component to perform cutting and cut the scale specifically.

[0031] (2) The threaded end of the screw B of the present invention penetrates through the wall of the centering tube and is under the clamping plate; when the shaft clamp fails, the threaded end of the screw B can limit the clamping plate to ensure that the lead screw can normally drive the cutting component and the detection component to move downward axially.

[0032] (3) This cleaning method is simple in operation, convenient to use, improves the maintenance efficiency and shortens the maintenance cycle. Description of the Drawings

[0033] Figure 1 is a schematic diagram of the use state of the device for cleaning the scale on the inner wall of the heating surface tube of the power station boiler of the present invention;

[0034] Figure 2 is Figure 1 the enlarged view I of

[0035] Figure 3 is Figure 1 the enlarged view II of

[0036] Figure 4 is Figure 1 the sectional view A - A of

[0037] Figure 5 is Figure 1 the sectional view B - B of

[0038] Figure 6 is Figure 1 the sectional view C - C of

[0039] Figure 7 is Figure 6 the enlarged view III of

[0040] Figure 8 is Figure 6 the enlarged view IV of

[0041] Figure 9 is the perspective view of the moving component;

[0042] Figure 10 is Figure 9 the enlarged view V of

[0043] Figure 11 is the perspective view of the detection component;

[0044] Figure 12 is Figure 11 the vertical sectional view of

[0045] Figure 13 is the indentation photo of the hardness indenter on the heating surface tube made of T91 ferritic steel;

[0046] Figure 14 is the indentation photo of the hardness indenter on the oxide scale of the heating surface tube made of T91 ferritic steel;

[0047] Figure 15 is the indentation photo of the hardness indenter on the heating surface tube made of G102 ferritic steel;

[0048] Figure 16 is the indentation photo of the hardness indenter on the oxide scale of the heating surface tube made of G102 ferritic steel;

[0049] Figure 17 is the flow chart of the device for cleaning the inner wall oxide scale of the heating surface tubes of the power station boiler of the present invention;

[0050] In the figure: 00. Heating surface tube, 11. Penetrating type lead screw motor, 12. Lead screw, 121. Clamping plate, 122. Shaft clamp, 13. Centering tube, 1311. Telescopic rod, 13111. Baffle plate, 1312. Traveling wheel, 1313. Outer top spring, 1314. Limit nut, 132. End ring, 1321. Arc-shaped connecting plate, 133. Limit spring groove, 1331. Square hole, 14. Installation end plate, 141. Radial groove A, 15. Screw A, 16. Screw B, 21. Cutting motor, 22. Motor disc, 23. Driving gear, 24. Driven gear, 25. Driven gear ring, 26. Rotating sleeve, 27. Oil-passing inner tube, 271. Oil-passing port, 272. Oil-passing cavity, 273. Sealing ring, 274. Plug, 275. Oil-passing ring groove, 28. Oil-passing outer tube, 281. Oil supply port, 29. Cutting cylinder, 2911. Fine turning tool bit, 2912. Rough turning tool bit, 31. Camera, 32. Loading cylinder, 321. Hardness indenter, 4. Double-headed bolt A, 5. Double-headed bolt B, 6. Double-headed bolt C, 7. Large ring, 8. Small disc. Specific embodiments

[0051] Example 1: Refer to Figure 1-16 , a device for cleaning the inner wall oxide scale of the heating surface tube of a power station boiler includes a moving component, a cutting component, and a detection component connected in sequence from top to bottom; the moving component is responsible for driving the cutting component and the detection component to move axially along the heating surface tube 00; the cutting component is responsible for detecting the inner wall oxide scale of the heating surface tube 00; the detection component is responsible for detecting the thickness of the inner wall oxide scale of the heating surface tube 00;

[0052] The moving component includes a through-type lead screw motor 11, a lead screw 12, and a centering pipe 13; the through-type lead screw motor 11 is vertically arranged at the nozzle of the heating surface pipe 00; the lead screw 12 is matched with the through-type lead screw motor 11; the through-type lead screw motor 11 outputs torque to drive the axial movement of the lead screw 12; the lower end of the lead screw 12 is connected to the upper end of the centering pipe 13; the axially moving lead screw 12 drives the axial movement of the centering pipe 13; at least three circumferentially distributed telescopic wheel mechanisms are provided in the middle of the centering pipe 13; the circumferentially distributed telescopic wheel mechanisms keep the centering pipe 13 in a centered state; the telescopic wheel mechanism includes a telescopic rod 1311, a traveling wheel 1312, an outer top spring 1313, and a limit nut 1314; the traveling wheel 1312 is rotatably connected to the outer end of the telescopic rod 1311; the circumferentially distributed telescopic wheel mechanisms keep the centering pipe 13 in a centered state; the telescopic rod 1311 passes through the outer top spring 1313, penetrates the centering pipe 13, and is threadedly engaged with the limit nut 1314, so that the traveling wheel 1312 slides on the inner wall of the heating surface pipe 00 to provide guidance for the axial movement of the centering pipe 13; the limit nut 1314 prevents the telescopic rod 1311 from coming out; a baffle 13111 is fixedly connected to the outer end of the telescopic rod 1311; one end of the outer top spring 1313 abuts against the baffle 13111, and the other end abuts against the outer wall of the centering pipe 13; the outer top spring 1313 drives the traveling wheel 1312 to keep abutting against the inner wall of the heating surface pipe 00;

[0053] The cutting component includes a cutting motor 21, a motor disc 22, a driving gear 23, a transmission gear 24, a transmission gear ring 25, a rotating sleeve 26, an oil-passing inner pipe 27, an oil-passing outer pipe 28, and a cutting cylinder 29;

[0054] The cutting motor 21 is installed on the motor disc 22; the motor disc 22 is respectively connected to the centering pipe 13 and the oil-passing inner pipe 27; the output shaft of the cutting motor 21 is coaxially and fixedly connected to the driving gear 23; the cutting motor 21 outputs torque to drive the driving gear 23 to rotate; the transmission gear ring 25 is sleeved outside the driving gear 23; the transmission gear 24 is arranged between the driving gear 23 and the transmission gear ring 25, leaving a gap between the transmission gear ring 25 and the driving gear 23 for the oil pipe and the electric wire to pass through; the transmission gear 24 meshes with the driving gear 23 and the transmission gear ring 25, so that the torque output by the cutting motor 21 can be transmitted to the transmission gear ring 25; the transmission gear ring 25 is connected to the oil-passing outer pipe 28 through the rotating sleeve 26 to transmit the torque to the oil-passing outer pipe 28; the cutting cylinder 29 is radially fixed on the outer wall of the oil-passing outer pipe 28; the piston rod end of the cutting cylinder 29 is provided with a cutting tool head; the piston rod extends outwards, and the cutting tool head abuts against the inner wall of the heating surface pipe 00; the oil-passing outer pipe 28 rotates to drive the cutting tool head to cut the oxide skin; several oil-passing ports 271 and an axial oil-passing cavity 272 are arranged at the upper end of the oil-passing inner pipe 27; the oil-passing ports 271 are connected to the oil pipe to realize the passage of the oil circuit; several oil-passing ring grooves 275 are axially distributed on the outer wall of the oil-passing inner pipe 27; the oil-passing ports 271, the oil-passing cavity 272 and the oil-passing ring grooves 275 are in one-to-one correspondence and communication to form the oil circuit route inside the oil-passing inner pipe 27; sealing rings 273 are arranged on the upper and lower sides of the oil-passing ring grooves 275 to seal the oil-passing ring grooves 275, so as to prevent the oil circuits of the respective oil-passing ring grooves 275 from interfering with each other and also ensure that the oil-passing outer pipe 28 can rotate relative to the oil-passing inner pipe 27; the oil-passing outer pipe 28 is hermetically sleeved outside the lower end of the oil-passing inner pipe 27 to prevent oil leakage; an oil supply port 281 corresponding to the oil-passing ring groove 275 is arranged on the outer wall of the oil-passing outer pipe 28; the oil supply port 281 is connected to the cutting cylinder 29 through a hose to realize oil supply to the cutting cylinder 29 and the telescopic movement of the piston rod;

[0055] The detection assembly includes a lighting camera 31 and a loading cylinder 32; the loading cylinder 32 is correspondingly arranged below the lighting camera 31; a hardness indenter 321 is fixed on the piston rod of the loading cylinder 32; the loading cylinder 32 drives the hardness indenter 321 to press against the inner wall of the heating surface pipe 00 to form an indentation; the lighting camera 31 takes a picture of the indentation; it is judged whether there is oxide skin on the inner wall of the heating surface pipe 00 by the size of the indentation to decide whether to use the cutting tool head for cutting; the oil pipe passes through the oil-passing inner pipe 27 and is connected to the loading cylinder 32.

[0056] Compared with the prior art, the present invention makes a judgment on whether there is oxide skin on the inner wall of the heating surface pipe 00 through the detection assembly, uses the cutting assembly for cutting, and uses the moving assembly to drive the cutting assembly and the detection assembly to move axially. The present invention makes a more accurate judgment on the oxide skin and can reduce the maintenance cost.

[0057] Most of the heating surface tubes 00 are vertically arranged; the moving component further includes a mounting end plate 14; the mounting end plate 14 is connected to the through-type lead screw motor 11 by screw A 15 and forms an integral body with the through-type lead screw motor 11; the mounting end plate 14 is buckled on the nozzle of the heating surface tube 00; the through-type lead screw motor 11 is also left outside the heating surface tube 00; the mounting end plate 14 is provided with a radial groove A 141 corresponding to the lead screw 12; the inner end of the radial groove A 141 can allow the lead screw 12 to pass through; the outer end of the radial groove A 141 penetrates the edge of the mounting end plate 14, opening a channel that can enter the interior of the heating surface tube 00 to facilitate the entry of oil pipes or electric wires.

[0058] The lower end of the lead screw 12 is rotatably connected to the upper end of the centering tube 13, which can reduce the influence of the self-rotation of the lead screw 12 on the axial movement stability of the cutting component and the detection component.

[0059] The upper end of the centering tube 13 is provided with an end ring 132 sleeved outside the lead screw 12; the lower end of the lead screw 12 is fixedly connected with a clamping plate 121; the lower end of the lead screw 12 is also provided with a shaft clamp 122; the end ring 132 is arranged between the clamping plate 121 and the shaft clamp 122 to realize the rotational connection between the centering tube 13 and the lead screw 12.

[0060] The outer edge of the end ring 132 is provided with an arc-shaped connecting plate 1321 extending downward; the screw B 16 penetrates the arc-shaped connecting plate 1321 and is threadedly connected with the centering tube 13; in this way, the end ring 132 and the centering tube 13 are detachably connected, which is convenient for assembly.

[0061] The threaded end of the screw B 16 penetrates the wall of the centering tube 13 and is located below the clamping plate 121; when the shaft clamp 122 fails, the threaded end of the screw B 16 can limit the clamping plate 121 to ensure that the lead screw 12 can normally drive the cutting component and the detection component to move axially downward.

[0062] The outer wall of the middle part of the centering tube 13 is provided with a limit spring groove 133 corresponding to the telescopic rod 1311; the outer top spring 1313 abuts against the bottom of the limit spring groove 133; the bottom of the limit spring groove 133 is a plane, which realizes effective contact with the outer top spring 1313; the groove wall of the limit spring groove 133 limits the outer top spring 1313 to prevent the outer top spring 1313 from bending sideways, ensuring that the elastic force of the outer top spring 1313 acts fully on the baffle 13111 and ensuring that the walking wheel 1312 is in full contact with the inner wall of the heating surface tube 00.

[0063] The inner end of the telescopic rod 1311 has a square radial cross-section; the bottom of the limit spring groove 133 is provided with a square hole 1331 corresponding to the telescopic rod 1311; the inner end of the telescopic rod 1311 is slidably matched with the square hole 1331 to realize the guiding of the radial expansion and contraction of the telescopic rod 1311.

[0064] The oil passage port 271 is arranged on the side surface of the upper end of the oil passage inner pipe 27, saving axial space and making the structure more compact; the upper end of the oil passage cavity 272 penetrates through the oil passage inner pipe 27; the oil passage cavity 272 can be machined by drilling from the upper end of the oil passage inner pipe 27; a plug 274 is installed at the upper port of the oil passage cavity 272 to seal the upper end of the oil passage cavity 272.

[0065] The device for cleaning the inner wall oxide scale of the heating surface tube of a power station boiler further includes a double-headed bolt A 4, a double-headed bolt B 5, a double-headed bolt C 6, a large ring 7, and a small disc 8; the upper end of the lighting camera 31 is connected to the large ring; the loading cylinder 32 is installed on the loading cylinder 32; the double-headed bolt A 4 connects the lower end of the centering pipe 13 to the motor disc 22; the double-headed bolt B 5 connects the motor disc 22 to the upper end of the oil passage inner pipe 27; the upper end of the double-headed bolt C 6 penetrates through the large ring 7 and is threadedly connected to the lower end of the oil passage inner pipe 27; the outer diameter of the large ring 7 > the inner diameter of the oil passage outer pipe 28; the lower end of the double-headed bolt C 6 is connected to the small disc 8; the detachable structure of the oxide scale cleaning device is realized through the double-headed bolt A 4, the double-headed bolt B 5, and the double-headed bolt C 6, which is convenient for later maintenance and replacement.

[0066] The working principle of this embodiment is as follows: the moving component is responsible for driving the cutting component and the detection component to move axially along the heated surface tube 00; the cutting component is responsible for detecting the oxide scale on the inner wall of the heated surface tube 00; the detection component is responsible for detecting the thickness of the oxide scale on the inner wall of the heated surface tube 00; in general, the oxide scale hardness of the heated surface tube 00 is much higher than that of the heated surface tube 00 body; the hardness level of the heated surface tube 00 body made of ferrite steel T91 is below 250HV1, and the hardness level of its oxide scale is above 400HV1; the hardness level of the heated surface tube 00 body made of ferrite steel G102 is below 220HV1, and the hardness level of its oxide scale is above 400HV1; the hardness level of the heated surface tube 00 body made of ferrite steel 12Cr1MoV is below 195HV1, and the hardness level of its oxide scale is above 400HV1. The loading cylinder 32 of the detection component presses the hardness press head 321 against the inner wall of the heated surface tube 00; the depth of the indentation left by the hardness press head 321 on the main body of the heated surface tube 00 is greater than the depth of the indentation left by the hardness press head 321 on the oxide scale; the image obtained by the camera 31 with lighting is reflected in the size of the indentation on the two-dimensional graph, and the maximum diagonal size can be used as an indicator parameter of the indentation size; therefore, if the diagonal size of the indentation obtained by the camera 31 with lighting is small to a certain extent, it can be judged that the position pressed by the hardness press head 321 is the oxide scale, otherwise it is determined that the position pressed by the hardness press head 321 is the main body of the heated surface tube 00; according to the judgment result, the cutting component is assisted to perform cutting, and the oxide scale is cut in a targeted manner. The piston rod extension and retraction control of the cutting cylinder 29 and the loading cylinder 32 can be achieved by monitoring the oil pipe flow; taking the cutting cylinder 29 as an example, hydraulic oil is transported to the far rod chamber, and the hydraulic oil of the near rod chamber is transported outward; if the hydraulic oil flow of the near rod chamber is greatly reduced, it means that the end of the piston rod has been against the inner wall of the heated surface tube 00; the timing starts from the time when the hydraulic oil flow of the near rod chamber begins to decrease significantly, and the oil pipe also transports hydraulic oil to the far rod chamber for a certain time before stopping; the cutting head feeds a certain amount of cutting; hydraulic oil is transported to the near rod chamber, and the hydraulic oil of the far rod chamber is transported outward; if the hydraulic oil flow of the far rod chamber stops, it means that the piston rod has retracted to the limit position; the control of the loading cylinder 32 is basically the same as that of the cutting cylinder 29, the difference is that the timing starts from the time when the hydraulic oil flow of the near rod chamber begins to decrease significantly, and the oil pipe also transports hydraulic oil to the far rod chamber for a certain time before stopping, which is carried out according to the requirements of the loading test.

[0067] Embodiment 2: It is basically the same as Embodiment 1, and the similarities are not repeated here. The differences are as follows: there are two cutting cylinders 29, which are respectively arranged at the upper and lower parts of the oil-passing outer tube 28; the cutting tool head on the piston rod of the upper cutting cylinder 29 is a fine turning tool head 2911, which is used for fine turning the inner wall of the heated surface tube 00 to remove the oxide scale; the cutting tool head on the piston rod of the upper cutting cylinder 29 is a rough turning tool head 2912, which is used for rough turning the inner wall of the heated surface tube 00 to remove the oxide scale.

[0068] There are several lighting cameras 31; the several lighting cameras 31 are circumferentially distributed relative to the lead screw 12 and cover a 360° viewing angle.

[0069] The motor disk 22 is provided with a radial groove B; the wires connected to the lighting camera 31 and the oil pipes communicating with the loading cylinder 32 and the oil port 271 pass through the radial groove B to reduce the wear of the wires and oil pipes on the heated surface pipe 00.

[0070] Embodiment 3: Refer to Figure 17 , a cleaning method for the inner wall oxide scale of the heated surface pipe of a power station boiler described in Embodiment 1, comprising the following steps:

[0071] ① Install the oxide scale cleaning device on the heated surface pipe 00

[0072] The loading cylinder 32, the detection component, the cutting component, and the centering pipe 13 sequentially enter the interior of the heated surface pipe 00; when the centering pipe 13 enters the heated surface pipe 00, first contract the telescopic rod 1311 towards the heated surface pipe 00. When the traveling wheel 1312 enters the heated surface pipe 00, then release the telescopic rod 1311; the telescopic rod 1311 is pushed outwards by the external spring 1313; the traveling wheel 1312 abuts against the inner wall of the heated surface pipe 00; when the through-type lead screw motor 11 is seated at the upper end of the heated surface pipe 00, the cutting component and the detection component are centered along with the centering pipe 13 and are located at the axial center position of the heated surface pipe 00;

[0073] ② The oxide scale cleaning device works

[0074] 2.1 Deliver hydraulic oil with a pressure of 9.8 N to the loading cylinder 32 to extend the piston rod of the loading cylinder 32, make the hardness indenter 321 abut against the inner wall of the heated surface pipe 00 for a certain period of time to leave an indentation; retract the piston rod of the loading cylinder 32;

[0075] 2.2 Drive the lead screw 12 to move downward by a distance h1 through the through-type lead screw motor 11; h1 is the height difference between the lighting camera 31 and the loading cylinder 32; the lighting camera 31 also descends and is just at a place opposite to the indentation to take a photo of the indentation;

[0076] 2.3 Judge whether there is oxide scale at this place according to the size of the indentation in the photo; if it is judged that there is oxide scale, execute step 2.4; if it is judged that there is no oxide scale, execute step 2.1;

[0077] 2.4 Hydraulic oil is delivered to the cutting cylinder 29 to make the cutting head contact the inner wall of the heated surface tube 00; the cutting motor 21 is started to rotate the cutting cylinder 29, and the cutting head cuts the inner wall of the heated surface tube 00; the through-type lead screw motor 11 drives the lead screw 12 to move axially downward by a distance h2; h2 is the height difference between the cutting head and the camera with lighting 31; the piston rod of the cutting cylinder 29 is retracted; h1 and h2 are equivalent;

[0078] 2.5 Repeat step 2.1 until the detection component passes through the entire section of the heated surface tube 00;

[0079] ③Review of oxide skin cleaning

[0080] 3.1 Rotate the cleaning device to a certain angle to avoid the original placement of the cleaning device;

[0081] 3.2 The through-type screw motor 11 drives the screw 12 to rise axially by a distance h3=h1+h2; the camera 31 with lighting and the loading cylinder 32 also rise; the hydraulic oil with a pressure of 9.8N is delivered to the loading cylinder 32, so that the piston rod of the loading cylinder 32 extends outward, and the hardness pressure head 321 is pressed against the inner wall of the heated surface tube 00 for a certain period of time, leaving an indentation; the piston rod of the loading cylinder 32 is retracted;

[0082] 3.3 The through-type lead screw motor 11 drives the lead screw 12 to descend axially by a distance h1; the camera 31 with illumination also descends and is located at a position opposite to the indentation to take a photo of the indentation;

[0083] 3.4 Determine whether there is oxide scale at the location based on the size of the indentation in the photo; if it is determined that there is oxide scale, proceed to step 3.5; if it is determined that there is no oxide scale, proceed to step 3.2;

[0084] 3.5 Hydraulic oil is delivered to the cutting cylinder 29 so that the cutting head is pressed against the inner wall of the heated surface tube 00; the cutting motor 21 is started to rotate the cutting cylinder 29 so that the cutting head cuts the inner wall of the heated surface tube 00; the through-type lead screw motor 11 drives the lead screw 12 to descend axially by a distance h2; the piston rod of the cutting cylinder 29 is retracted; the through-type lead screw motor 11 drives the lead screw 12 to ascend axially by a distance h2;

[0085] 3.6 Execute step 3.2 until the centering tube 13 returns to the upper end of the heating surface tube 00.

[0086] This embodiment can clean the oxide scale on most of the heating surface tubes 00.

[0087] Embodiment 4: It is basically the same as Embodiment 3, and the similarities are not repeated here. The difference is that: the oxide scale cleaning device for the inner wall of the heating surface tube of the power station boiler described in Embodiment 2 is used. The circumferentially distributed cameras with lighting 31 can monitor the inner wall of the heating surface tube 00.

[0088] In step 3.2, the illumination camera 31 monitors the inner wall of the heating surface tube 00 during the ascending process; traces will be left on the inner wall of the heating surface tube 00 after cutting; there will be edge lifting if the oxide scale cutting is incomplete; if the image captured by the illumination camera 31 shows edge lifting of the oxide scale, it is directly determined that it is due to the oxide scale, and step 3.7 is executed.

[0089] 3.7 Supply hydraulic oil to the cutting cylinder 29 to make the cutting head abut against the inner wall of the heating surface tube 00; start the cutting motor 21 to rotate the cutting cylinder 29, and the cutting head cuts the inner wall of the heating surface tube 00; drive the lead screw 12 to axially descend by a distance h3 through the through-type lead screw motor 11; retract the piston rod of the cutting cylinder 29; drive the lead screw 12 to axially ascend by a distance h3 through the through-type lead screw motor 11; execute step 3.6.

[0090] In this embodiment, h2 is the height difference between the rough turning tool head 2912 and the illumination camera 31; h4 is the height difference between the finish turning tool head 2911 and the rough turning tool head 2912.

[0091] In step ②, supply oil to the cutting cylinder 29 with the rough turning tool head 2912; in step ③, supply oil to the cutting cylinder 29 with the finish turning tool head 2911.

[0092] In step 3.2, drive the lead screw 12 to axially ascend by a distance h3 = h1 + h2 + h4 through the through-type lead screw motor 11;

[0093] In step 3.5, drive the lead screw 12 to axially descend by a distance h2 + h4 through the through-type lead screw motor 11; retract the piston rod of the cutting cylinder 29; drive the lead screw 12 to axially ascend by a distance h2 + h4 through the through-type lead screw motor 11.

[0094] Embodiment Five: It is basically the same as Embodiment Three or Four, and the same parts will not be elaborated again. The differences are as follows: The recheck of the oxide scale cleaning situation in step ③ is combined with the operation of the oxide scale cleaning device in step ②.

[0095] In step 2.5, drive the lead screw 12 to axially ascend by a distance h3 = h1 + h2 through the through-type lead screw motor 11; execute step 2.1 until the detection component passes through the entire section of the heating surface tube 00.

Claims

1. A device for cleaning the inner wall oxide scale of the heating surface tubes of a power station boiler, characterized in that, It includes a moving component, a cutting component, and a detection component that are connected successively from top to bottom; The moving component includes a through-type lead screw motor, a lead screw, and a centering tube; the through-type lead screw motor is vertically arranged at the nozzle of the heating surface tube; the lead screw is matched with the through-type lead screw motor; the lower end of the lead screw is connected to the upper end of the centering tube; at least three circumferentially distributed telescopic wheel mechanisms are provided in the middle of the centering tube; the telescopic wheel mechanism includes a telescopic rod, a traveling wheel, an outer top spring, and a limit nut; the traveling wheel is rotatably connected to the outer end of the telescopic rod; the telescopic rod passes through the outer top spring, penetrates the centering tube, and is threadedly matched with the limit nut; a baffle is fixedly connected to the outer end of the telescopic rod; one end of the outer top spring abuts against the baffle, and the other end abuts against the outer wall of the centering tube; The cutting component includes a cutting motor, a motor disc, a driving gear, a transmission gear, a transmission gear ring, a rotating sleeve, an oil-passing inner tube, an oil-passing outer tube, and a cutting cylinder; The cutting motor is installed on the motor disc; the motor disc is connected to the centering tube and the oil-passing inner tube respectively; the output shaft of the cutting motor is coaxially fixedly connected with the driving gear; the transmission gear ring is sleeved outside the driving gear; the transmission gear is arranged between the driving gear and the transmission gear ring; the transmission gear meshes with the driving gear and the transmission gear ring; the transmission gear ring is connected to the oil-passing outer tube through the rotating sleeve; the cutting cylinder is radially fixed on the outer wall of the oil-passing outer tube; a cutting tool head is provided at the end of the piston rod of the cutting cylinder; several oil-passing ports and an axial oil-passing cavity are provided at the upper end of the oil-passing inner tube; several oil-passing ring grooves are axially evenly distributed on the outer wall of the oil-passing inner tube; the oil-passing ports, the oil-passing cavity, and the oil-passing ring grooves are in one-to-one correspondence and communication; sealing rings are provided on both sides above and below the oil-passing ring grooves; the oil-passing outer tube is hermetically sleeved outside the lower end of the oil-passing inner tube; an oil supply port corresponding to the oil-passing ring groove is provided on the outer wall of the oil-passing outer tube; the oil supply port is connected to the cutting cylinder through a hose; The detection component includes a camera with illumination and a loading cylinder; the loading cylinder is correspondingly arranged below the camera with illumination; a hardness indenter is fixed on the piston rod of the loading cylinder; an oil pipe passes through the oil-passing inner tube and is connected to the loading cylinder.

2. The device for cleaning the inner wall oxide scale of the heating surface tubes of a power station boiler according to claim 1, wherein: The moving component further includes a mounting end plate; the mounting end plate is connected to the through-type lead screw motor by screw A; the mounting end plate is buckled on the nozzle of the heating surface tube; the mounting end plate is provided with a radial groove A that matches the lead screw; the outer end of the radial groove A penetrates the edge of the mounting end plate.

3. The device for cleaning the inner wall oxide scale of the heating surface tubes of a utility boiler according to claim 1, wherein: The lower end of the lead screw is rotatably connected to the upper end of the centering tube.

4. The device for cleaning the inner wall oxide scale of the heating surface tubes of a power station boiler according to claim 1, wherein: A limit spring groove corresponding to the telescopic rod is provided on the outer wall of the middle part of the centering tube; the outer top spring abuts against the bottom of the limit spring groove.

5. The device for cleaning the inner wall of the heating surface tube of a power station boiler according to claim 4, wherein: The inner end of the telescopic rod has a square cross-section; a square hole corresponding to the telescopic rod is provided at the bottom of the limit spring groove; the inner end of the telescopic rod is slidably matched with the square hole.

6. The device for cleaning the inner wall of the oxidized skin of the heating surface tubes of a power station boiler according to claim 1, wherein: The oil-passing ports are arranged on the side surface of the upper end of the oil-passing inner tube; the upper end of the oil-passing cavity penetrates the oil-passing inner tube; a plug is installed at the upper port of the oil-passing cavity.

7. The device for cleaning the inner wall oxide scale of the heating surface tubes of a power station boiler according to claim 1, wherein: There are two cutting cylinders, which are respectively arranged at the upper and lower parts of the oil-passing outer tube; the cutting tool head on the piston rod of the upper cutting cylinder is a fine turning tool head; the cutting tool head on the piston rod of the lower cutting cylinder is a rough turning tool head.

8. The device for cleaning the inner wall oxide scale of the heating surface tubes of a power station boiler according to claim 1, wherein: It also includes stud A, stud B, stud C, large ring, and small disc; the upper end of the lighting camera is connected to the large disc; the loading cylinder is installed on the loading cylinder; stud A connects the lower end of the centering pipe to the motor disc; stud B connects the motor disc to the upper end of the oil-passing inner pipe; the upper end of stud C penetrates through the large ring and is threadedly connected to the lower end of the oil-passing inner pipe; the outer diameter of the large ring > the inner diameter of the oil-passing outer pipe; the lower end of stud C is connected to the small disc.

9. The device for cleaning the inner wall oxide scale of the heating surface tubes of a power station boiler according to claim 8, characterized in that: The motor disc is provided with a radial groove B; the wires connected to the lighting camera and the oil pipes connected to the loading cylinder and the oil port pass through the radial groove B.

10. A cleaning method for the inner wall oxide scale cleaning device of the heating surface tubes of a utility boiler as described in claim 1, characterized in that: It includes the following steps: ① Install the scale removal device onto the heating surface pipe The loading cylinder, the detection component, the cutting component, and the centering pipe enter the interior of the heating surface pipe in sequence; when the centering pipe enters the heating surface pipe, first contract the telescopic rod towards the heating surface pipe, and when the traveling wheels enter the heating surface pipe, then release the telescopic rod; the telescopic rod extends outwards under the top pressure of the outer top spring; the traveling wheels abut against the inner wall of the heating surface pipe; when the through-type lead screw motor base is at the upper end of the heating surface pipe, the cutting component and the detection component are centered along with the centering pipe and are at the axial center position of the heating surface pipe; ② The scale removal device operates 2.1 Deliver hydraulic oil with a pressure of 9.8 N to the loading cylinder to extend the piston rod of the loading cylinder, make the hardness indenter abut against the inner wall of the heating surface pipe for a certain period of time to leave an indentation; retract the piston rod of the loading cylinder; 2.2 Drive the lead screw shaft to move downward by a distance h1 through the through-type lead screw motor; h1 is the height difference between the lighting camera and the loading cylinder; the lighting camera also descends and is just at a position opposite to the indentation to take a photo of the indentation. 2.3 Judge whether there is scale at this place according to the size of the indentation in the photo; if it is judged that there is scale, execute step 2.4; if it is judged that there is no scale, execute step 2.1; 2.4 Deliver hydraulic oil to the cutting cylinder to make the cutting tool head abut against the inner wall of the heating surface pipe; start the cutting motor to rotate the cutting cylinder, and the cutting tool head cuts the inner wall of the heating surface pipe; drive the lead screw shaft to move downward by a distance h2 through the through-type lead screw motor; h2 is the height difference between the cutting tool head and the lighting camera; retract the piston rod of the cutting cylinder; h1 and h2 are equivalent. 2.5 Repeat step 2.1 until the detection component passes through the entire section of the heating surface pipe.

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