A system and method for repairing waste boilers.

Abstract

This invention discloses a repair system for a waste heat exchanger, comprising a welding unit and a detection unit. The welding unit consists of three mutually perpendicular embedded linkage components (X, Y, Z) and a welding assembly. The detection unit is installed circumferentially along the waste heat exchanger, dividing the circumference into a first detection zone, a second detection zone, and a flaw detection zone. The first ultrasonic transmitter performs a preliminary scan of the first detection zone, and the second ultrasonic transmitter performs a preliminary scan of the second detection zone. If either the first or second ultrasonic receiver receives an echo signal higher than its rated value, it is recorded. After the preliminary scan, the ultrasonic detector detects the defect waveform of the waste heat exchanger, and a verification scan is performed based on the abnormal echo signal and the defect waveform of the waste heat exchanger structure. This system provides a more comprehensive and accurate detection of the weld quality of the waste heat exchanger, enabling timely discovery and handling of potential defects.

Description

Technical Field

[0001] This invention relates to waste pot repair technology, and more particularly to a waste pot repair system and repair method. Background Technology

[0002] In coal chemical conversion systems, the waste heat exchange boilers are prone to defects (cracks) due to their operating environment and the media they pass through, resulting in a generally short service life. To extend their service life, welding repair is usually performed. Existing repair processes generally use direct welding, which often leads to secondary cracking after repair, resulting in a low welding success rate. Summary of the Invention

[0003] To address the shortcomings of the existing technology, this invention proposes a system and method for repairing waste boilers.

[0004] The technical solution of the present invention is achieved as follows:

[0005] A system for repairing waste cookers, characterized in that it comprises:

[0006] The welding unit consists of three mutually perpendicular embedded linkage components (X, Y, and Z) and a welding assembly. The Z-axis linkage component is an adjustment axis, the Y-axis linkage component is a control axis, and the X-axis linkage component is a correction axis, all used to control the movement of the welding assembly. A vision sensor is provided at one end of the welding assembly, and the vision sensor is horizontally opposite the welding assembly along the Y-axis linkage component. The vision sensor is used to control the movement of the welding assembly along the weld centerline.

[0007] A detection unit is installed circumferentially along the waste boiler, dividing the circumference into a first detection area, a second detection area, and a flaw detection area. The detection unit includes a first ultrasonic transmitter, a first ultrasonic receiver, a second ultrasonic transmitter, a second ultrasonic receiver, and an ultrasonic detector. The first ultrasonic transmitter and the first ultrasonic receiver are located in the first detection area, the second ultrasonic transmitter and the second ultrasonic receiver are located in the second detection area, and the ultrasonic detector is located in the flaw detection area.

[0008] The first ultrasonic transmitter performs a preliminary scan of the first detection area, and the second ultrasonic transmitter performs a preliminary scan of the second detection area. If the first ultrasonic receiver or the second ultrasonic receiver receives an echo signal higher than the rated value, it is recorded and marked. After the preliminary scan, the ultrasonic detector detects the defect waveform of the waste pot and performs a verification scan based on the abnormal echo signal and the defect waveform of the waste pot structure.

[0009] In this invention, the first ultrasonic transmitter includes a connecting plate, and both ends of the connecting plate are provided with connecting hinges. The two connecting hinges are connected by a fitting hinge. A probe is provided below the connecting plate. The fitting hinge is used to control the contact force between the probe and the waste pot wall.

[0010] In this invention, a transition component is provided between the first ultrasonic transmitters. The transition component includes connecting plates on the left and right sides, a hinge rod is provided between the two connecting plates, a roller is provided directly above the connecting plates, and multiple connecting rods are provided inside the connecting plates. The multiple connecting rods are connected to the mounting rod, and the first ultrasonic transmitter is provided below the mounting rod. The vertical movement distance of the mounting rod is controlled by the multiple connecting rods, thereby ensuring that the first ultrasonic transmitter is always coupled to the pot wall.

[0011] In this invention, the probe has multiple sets of ultrasonic refraction angles, and the probe refraction angles K are K1, K2, K3, K4 and K5, wherein the refraction angle K1 is 70.6°, the refraction angle K2 is 67.5°, the refraction angle K3 is 56.6°, the refraction angle K4 is 50.1° and the refraction angle K5 is 44.7°.

[0012] In this invention, the welding unit includes two Y-axis extension frames, with a Y-axis slide rail above each Y-axis extension frame. The gantry frame has an N-type structure and is slidably connected above the two Y-axis slide rails. A first drive motor is provided on one side of the gantry frame to control the movement of the gantry frame on the slide rail. A top plate is provided at the top of the gantry frame, with an X-axis slide rail arranged laterally on the top plate. A sliding frame is slidably mounted along the X-axis slide rail. A second drive motor is provided on one side of the X-axis slide rail to control the movement of the sliding frame on the X-axis slide rail. A Z-axis guide plate is provided below the sliding frame, with a Z-axis slider slidably mounted on the outer side of the Z-axis guide plate.

[0013] In this invention, a welding assembly is installed on the Z-axis slider, and a third drive motor is also installed on the top of the Z-axis guide plate. The third drive motor is used to drive the Z-axis slider and the welding assembly to slide along the Z-axis.

[0014] In this invention, the welding assembly includes a connecting seat, which is fixedly connected to the Z-axis slider and moves up and down with the Z-axis slider. One end of the connecting seat is provided with a large arm, which is connected to a rocker arm via a middle arm. The other end of the rocker arm is connected to the welding head.

[0015] A method for repairing a waste pot, characterized by comprising the following steps:

[0016] Step 1: The waste boiler is inspected using the waste boiler repair system, and the defective parts are marked.

[0017] Step 2: Remove defects with a depth of no more than 20mm. Grind the defect with a grinder to clean it. For defects with a depth greater than 20mm, clean the defect with a carbon arc gouging machine and grind it with a grinder to clean away slag and other debris. Perform MT testing on the ground area to check whether the defect has been cleaned and whether there are any other defects.

[0018] Step 3: Hydrogen removal treatment. The entire equipment to be repaired is heated to about 350 degrees Celsius using heat treatment equipment and kept at 350 degrees Celsius for 24 hours.

[0019] Step 4: Repair welding of defective parts. Before repair welding, preheat the welding area with electric heating. The preheating temperature is ≥150℃, and the interpass temperature is less than or equal to 200℃. Weld the defective parts according to the corresponding welding process. The equipment temperature is not lower than 300 degrees during the welding process.

[0020] Step 5: Non-destructive testing of the repaired weld area. After the weld has cooled for 24 hours, the weld joint is subjected to 100% UT and MT testing.

[0021] Step 6: Heat treatment. Stress relief heat treatment is performed on the entire weld seam between the tube sheet and the tube box using electric heating. Electric heating plates are required on both the inner and outer surfaces of the weld seam, and the internal heating plates are fixed with an annular ring.

[0022] Step 7: Non-destructive testing of internal and external welds to determine whether the welds are complete.

[0023] The waste pot repair system and method of this invention have the following beneficial effects:

[0024] 1. Three-axis linkage design of the welding unit: The welding unit consists of three mutually perpendicular and linked embedded sliding rails (X, Y, and Z), enabling precise positioning and movement of the welding components in three-dimensional space. The Z-axis serves as the adjustment axis, ensuring precise alignment of the welding components with the weld seam of the waste heat exchanger; the Y-axis acts as the control axis, controlling the forward or backward movement of the welding components along the weld seam; and the X-axis serves as the correction axis, ensuring the welding components are aligned with the weld centerline in real time. This design significantly improves welding accuracy and efficiency.

[0025] 2. Application of PLC Controllers: By installing PLC controllers on the X-axis and Y-axis slide rails, high-speed pulses can be generated to control the speed and position of the drive motors, thereby achieving real-time detection and tracking of the weld position. This not only improves the automation level of welding but also reduces the difficulty and error of manual operation.

[0026] 3. Application of Vision Sensors: The vision sensors installed on the sliding frame can detect and locate the welding position of the waste pot, acquire and process images of the weld, and extract the weld centerline. This feeds motion parameters back to the drive motor in real time, driving the welding components to perform the welding operation and keeping them always located on the weld centerline. This design further improves the accuracy and quality of welding.

[0027] 4. Zonal Inspection Design of the Inspection Unit: The inspection unit divides the waste heat exchanger into different inspection zones using an ultrasonic transmitter and receiver, including a first inspection zone, a second inspection zone, and a flaw detection zone. This zonal inspection design allows for more comprehensive and accurate inspection of the weld quality of the waste heat exchanger, enabling timely detection and handling of potential defects.

[0028] 5. Application of Ultrasonic Detectors: Ultrasonic detectors can perform defect waveform detection on waste heat exchangers, conduct detailed scanning of marked areas, and determine the type of weld defect based on the location and waveform of abnormal echo signals. This design improves the accuracy and reliability of detection, providing strong support for subsequent weld quality assessment.

[0029] 6. Fitting Hinge Design: The fitting hinge in the ultrasonic transmitter ensures that the probe is always in contact with the transducer, while also providing a certain degree of floating capability. This design guarantees good coupling between the probe and the transducer, while avoiding damage to the probe due to excessive friction. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the welding unit of the present invention;

[0031] Figure 2 This is a schematic diagram of the welding unit of the present invention from another angle;

[0032] Figure 3 This is another angular structural diagram of the welding unit of the present invention;

[0033] Figure 4 This is a schematic diagram of the installation structure of the detection unit of the present invention;

[0034] Figure 5 This is a partial structural schematic diagram of the detection unit of the present invention;

[0035] Figure 6 This is a schematic diagram of the structure of the waste pot of the present invention;

[0036] Figure 7 This is a schematic diagram showing the installation of the detection unit and the waste heat exchanger of the present invention;

[0037] Figure 8 This is a partial structural schematic diagram of the detection unit of the present invention;

[0038] Figure 9 This is a schematic diagram illustrating the principle of the detection unit of the present invention;

[0039] Figure 10 A flowchart for changing the waste boiler repair method.

[0040] The reference numerals in the attached drawings are as follows: 100 Welding unit, 101 Y-axis extension frame, 102 Y-axis slide rail, 103 First drive motor, 104 Gantry frame, 105 Top plate, 106 X-axis slide rail, 107 Second drive motor, 108 Sliding frame, 109 Z-axis guide plate, 110 Z-axis slider, 111 Third drive motor, 112 Connecting seat, 113 Main arm, 114 Middle arm, 115 Rocker arm, 116 Welding head, 117 Vision sensor, 200 Detection unit, 21 First ultrasonic transmitter, 22 First ultrasonic receiver, 23 Second ultrasonic transmitter, 24 Second ultrasonic receiver, 25 Ultrasonic detector, 201 Connecting plate, 202 Connecting hinge, 203 Fitting hinge, 204 Probe, 21A Adapter component, 21A1 Connecting plate, 21A2 Hinge rod, 21A3 Roller, 21A4 Connecting rod, 21A5 Mounting rod. Detailed Implementation

[0041] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0042] like Figures 1 to 9 As shown, the waste pot repair system of this embodiment includes a welding unit 100 and a detection unit 200.

[0043] like Figures 1 to 3 As shown, the welding unit 100 consists of three interconnected components—X, Y, and Z—with mutually perpendicular embedded sliding rails. The Z-axis is an adjustment axis, used before welding to ensure the welding assembly aligns with the weld seam of the boiler; during welding, the Z-axis remains stationary. The Y-axis is a control axis, used to control the forward or backward movement of the weld assembly along the weld seam. The X-axis is a correction axis, primarily used to ensure the weld assembly is aligned with the weld centerline in real time.

[0044] Specifically, the welding unit 100 includes two Y-axis extension frames 101, with Y-axis slide rails 102 positioned above each Y-axis extension frame 101. The gantry frame 104 has an N-type structure and is slidably connected above the two Y-axis slide rails 102. A first drive motor 103 is located on one side of the gantry frame 104, controlling its movement on the slide rails. An upper top plate 105 is located at the top of the gantry frame 104, with an X-axis slide rail 106 arranged laterally on the upper top plate 105. A sliding frame 108 is slidably mounted along the X-axis slide rail 106, with a second drive motor 107 located on one side of the X-axis slide rail 106, controlling its movement on the X-axis slide rail 106. A Z-axis guide plate 109 is located below the sliding frame 108, with a Z-axis slider 110 slidably mounted on the outer side of the Z-axis guide plate 109. A welding assembly is mounted on the Z-axis slider 110, and a third drive motor 111 is mounted on the top of the Z-axis guide plate 109. The third drive motor 111 is used to drive the Z-axis slider 110 and the welding assembly to slide along the Z-axis. PLC controllers are mounted on the X-axis slide rail 106 and the Y-axis slide rail 102, respectively. High-speed pulses generated by the PLC controllers control the speed and position of the first drive motor 103, the second drive motor 107, and the third drive motor 111, enabling real-time detection and tracking of the weld position.

[0045] In this embodiment, a vision sensor 117 is provided at the end of the sliding frame 108 away from the welding assembly, and the vision sensor 117 is horizontally opposite the welding assembly along the Y-axis.

[0046] First, ensure that the gap between the waste pot and the welding rod is sufficiently tight and that there is no misalignment, and that the direction of the gap is consistent with the axis. Then, adjust the distance and position between the gap and the vision sensor 117 to roughly align them. The vision sensor 117 detects and positions the welding position of the waste pot, acquires and processes images of the weld seam, and extracts the weld centerline. The motion parameters are fed back in real time to the first drive motor 103, the second drive motor 107, and the third drive motor 111, driving the welding assembly to perform the welding operation, keeping it always located on the weld centerline. The welding assembly includes a connecting seat 112, which is fixedly connected to the Z-axis slider 110 and moves up and down with the Z-axis slider 110. One end of the connecting seat 112 is provided with a large arm 113, which is connected to a rocker arm 115 via a middle arm 114. The other end of the rocker arm 115 is connected to the welding head 116. The welding head 116 is finely adjusted at the welding position of the waste pot by the main arm 113, the middle arm 114 and the rocker arm 115 to ensure welding quality.

[0047] like Figures 4 to 5As shown, a detection unit 200 is also provided in the axial direction of the welding unit 100. The detection unit 200 includes a first ultrasonic transmitter 21, a first ultrasonic receiver 22, a second ultrasonic transmitter 23, a second ultrasonic receiver 24, and an ultrasonic detector 25 installed circumferentially on the waste transfer pot 20. The first ultrasonic transmitter 21 and the second ultrasonic transmitter 23 are located on both sides of their upper ends, and the angle between the first ultrasonic transmitter 21 and the second ultrasonic transmitter 23 is 90°. The first ultrasonic receiver 22 and the second ultrasonic receiver 24 are installed on both sides of the waste transfer pot 20, and the first ultrasonic receiver 22 and the second ultrasonic receiver 24 are on the same horizontal line. The ultrasonic detector 25 is located on the top of the waste transfer pot 20, and the angle between it and the first ultrasonic receiver 22 or the second ultrasonic receiver 24 is 90°. The detection unit 200 divides the waste transfer pot 20 into a first detection area, a second detection area, and a flaw detection area. The first ultrasonic transmitter 21 and the first ultrasonic receiver 22 are located in the first detection area, the second ultrasonic transmitter 23 and the second ultrasonic receiver 24 are located in the second detection area, and the ultrasonic detector 25 is located in the flaw detection area.

[0048] Specifically, the first ultrasonic transmitter 21 first performs a preliminary scan of the weld seam according to the flaw detection surface divided by the first detection area. The detection probe is placed at one end of the weld seam and scanned cyclically perpendicular to the weld crack direction to ensure the ultrasonic beam can penetrate the first detection area. A slow scanning speed should be maintained, and the overlap rate of the probe width should be kept between 5% and 10%. If the first ultrasonic receiver 22 receives an echo signal higher than the rated value, it is recorded. The second ultrasonic transmitter 23 and the second ultrasonic receiver 24 operate on the same principle as the first ultrasonic transmitter 21 and the first ultrasonic receiver 22. After the preliminary scan, the defect waveform of the waste heat exchanger is detected by the ultrasonic detector 25. At this time, a fine scan is performed on the recorded marked area. Based on the location and waveform of the abnormal echo signal, combined with the defect waveform identification characteristics of the waste heat exchanger structure, the type of weld defect is determined, and the waveform amplitude is recorded. For defects with abnormal waveforms and no corresponding waveform characteristics, a verification scan can be performed to further ensure the accuracy of the detection.

[0049] The first ultrasonic transmitter 21 and the second ultrasonic transmitter 23 have the same structure. The first ultrasonic transmitter 21 includes a connecting plate 201, with connecting hinges 202 at both ends. The two connecting hinges 202 are connected by a fitting hinge 203. A probe 204 is located below the connecting plate 201, which is used to emit and receive reflected waves. When the probe 204 is in contact with the wall of the waste heat exchanger, the force needs to be controlled. If the force is too small, the coupling effect will be poor; if the force is too large, it will easily increase friction and damage the probe. Therefore, during installation, the fitting hinge 203 is in contact with the side wall of the waste heat exchanger to ensure that the probe 204 is always in contact with the waste heat exchanger, while also having a certain degree of floating function.

[0050] Furthermore, such as Figures 6 to 8 As shown, the walls of the waste pot 20 have misaligned joints, resulting in inconsistent heights on both sides. When the probe 204 is positioned against the walls, it tilts, affecting the distance between the probe 204 and the pot wall, and consequently, the coupling between the probe 204 and the waste pot wall. Therefore, a transition component 21A is provided between the two first ultrasonic transmitters 21. The transition component 21A includes connecting plates 21A1 on the left and right sides, and a hinge rod 21A2 is provided between the two connecting plates 21A1. A roller 21A3 is provided directly above the connecting plate 21A1, and multiple connecting rods 21A4 are provided inside the connecting plate 21A1, which are connected to the mounting rod 21A5. The first ultrasonic transmitter 21 is located below the mounting rod 21A5, and the vertical movement distance of the mounting rod 21A5 is controlled by the multiple connecting rods 21A4, thereby ensuring that the first ultrasonic transmitter 21 is always coupled to the pot wall.

[0051] Furthermore, such as Figure 9 As shown, to ensure the scanning range of the ultrasonic transmitter, probe 204 has multiple sets of ultrasonic refraction angles. Kmax represents the coverage range of the probe with the largest K-value, and Kmin represents the coverage range of the probe with the smallest K-value. Multiple probes with different K-values ​​are arranged linearly to form a probe group, which can expand the sound beam coverage and scan a larger area at once. The K-values ​​of probes 204 are K1, K2, K3, K4, and K5. The refraction angles are K1 (70.6°), K2 (67.5°), K3 (56.6°), K4 (50.1°), and K5 (44.7°).

[0052] Furthermore, such as Figure 10 As shown, this embodiment also discloses a method for repairing a waste pot, including the following steps:

[0053] Step 1: Using the waste boiler repair system according to any one of claims 1-7, inspect the waste boiler and mark the defective parts;

[0054] Step 2: Remove defects with a depth of no more than 20mm. Grind the defect with a grinder to clean it. For defects with a depth greater than 20mm, clean the defect with a carbon arc gouging machine and grind it with a grinder to clean away slag and other debris. Perform MT testing on the ground area to check whether the defect has been cleaned and whether there are any other defects.

[0055] Step 3: Hydrogen removal treatment. The entire equipment to be repaired is heated to approximately 350 degrees Celsius using heat treatment equipment and held at this temperature for 24 hours. After hydrogen removal treatment, the entire equipment will not experience hydrogen embrittlement during subsequent welding processes, greatly improving the welding success rate.

[0056] Step 4: Repair welding of defective parts. Before repair welding, preheat the welding part with electric heating. The preheating temperature is ≥150℃. Keep the interpass temperature less than or equal to 200℃. Weld the defective part according to the corresponding welding process. During the welding process, the equipment temperature is not lower than 300 degrees. A smaller interpass temperature difference will improve the success rate of welding in one go and reduce the welding difficulty caused by excessive temperature difference.

[0057] Step 5: Non-destructive testing of the repaired weld area. After the weld has cooled for 24 hours, the weld joint is subjected to 100% UT and MT testing.

[0058] Step 6: Heat treatment. Stress-relieving heat treatment is performed on the entire weld seam between the tube sheet and the tube box using electric heating. Electric heating elements are installed on both the inner and outer surfaces of the weld seam, with the internal heating elements fixed by a ring. Stress relief eliminates secondary cracking caused by stress during equipment use, thus extending the equipment's service life.

[0059] Step 7: Non-destructive testing of internal and external welds to determine whether the welds are complete.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A system for repairing waste boilers, characterized in that, include: The welding unit consists of three mutually perpendicular embedded linkage components (X, Y, and Z) and a welding assembly. The Z-axis linkage component is an adjustment axis, the Y-axis linkage component is a control axis, and the X-axis linkage component is a correction axis, all used to control the movement of the welding assembly. A vision sensor is provided at one end of the welding assembly, and the vision sensor is horizontally opposite the welding assembly along the Y-axis linkage component. The vision sensor is used to control the movement of the welding assembly along the weld centerline. A detection unit is installed circumferentially along the waste boiler, dividing the circumference into a first detection area, a second detection area, and a flaw detection area. The detection unit includes a first ultrasonic transmitter, a first ultrasonic receiver, a second ultrasonic transmitter, a second ultrasonic receiver, and an ultrasonic detector. The first ultrasonic transmitter and the first ultrasonic receiver are located in the first detection area, the second ultrasonic transmitter and the second ultrasonic receiver are located in the second detection area, and the ultrasonic detector is located in the flaw detection area. The first and second ultrasonic transmitters are located on opposite sides of the upper end, with an angle of 90° between them. The first and second ultrasonic receivers are mounted on opposite sides of the waste conversion vessel, aligned horizontally. The ultrasonic detector is located at the top of the waste conversion vessel, with an angle of 90° between it and either the first or second ultrasonic receiver. In this process, the first ultrasonic transmitter performs a preliminary scan of the first detection area, and the second ultrasonic transmitter performs a preliminary scan of the second detection area. If either the first or second ultrasonic receiver receives an echo signal higher than the rated value, it is recorded and marked. After the preliminary scan, the ultrasonic detector detects the defect waveform of the waste pot and performs a verification scan based on the abnormal echo signal and the defect waveform of the waste pot structure. The first ultrasonic transmitter includes a connecting plate, with connecting hinges at both ends. The two connecting hinges are connected by a fitting hinge. A probe is disposed below the connecting plate. The fitting hinge is used to control the contact force between the probe and the waste pot wall. A connecting component is provided between the first ultrasonic transmitters. The connecting component includes connecting plates on the left and right sides, and a hinge rod is provided between the two connecting plates. A roller is provided directly above the connecting plates, and multiple connecting rods are provided inside the connecting plates. The multiple connecting rods are connected to a mounting rod, and the first ultrasonic transmitter is provided below the mounting rod. The vertical movement distance of the mounting rod is controlled by the multiple connecting rods. Therefore, even when there are misaligned joints in the waste pot wall, resulting in inconsistent heights on both sides of the pot wall, the first ultrasonic transmitter is always coupled to the pot wall. The probe has multiple sets of ultrasonic refraction angles, and the probe refraction angles K are K1, K2, K3, K4 and K5, respectively. Among them, the refraction angle K1 is 70.6°, the refraction angle K2 is 67.5°, the refraction angle K3 is 56.6°, the refraction angle K4 is 50.1° and the refraction angle K5 is 44.7°.

2. The waste boiler repair system according to claim 1, characterized in that, The welding unit includes two Y-axis extension frames, with Y-axis slide rails mounted above the Y-axis extension frames. The gantry frame has an N-type structure and is slidably connected above the two Y-axis slide rails. A first drive motor is mounted on one side of the gantry frame to control the movement of the gantry frame on the slide rails. A top plate is mounted on the top of the gantry frame, with an X-axis slide rail mounted laterally on the top plate. A sliding frame is slidably mounted along the X-axis slide rail. A second drive motor is mounted on one side of the X-axis slide rail to control the movement of the sliding frame on the X-axis slide rail. A Z-axis guide plate is mounted below the sliding frame, with a Z-axis slider slidably mounted on the outer side of the Z-axis guide plate.

3. The waste boiler repair system according to claim 2, characterized in that, A welding assembly is mounted on the Z-axis slider, and a third drive motor is also mounted on the top of the Z-axis guide plate. The third drive motor is used to drive the Z-axis slider and the welding assembly to slide along the Z-axis.

4. The waste boiler repair system according to claim 3, characterized in that, The welding assembly includes a connecting seat, which is fixedly connected to the Z-axis slider and moves up and down with the Z-axis slider. One end of the connecting seat is provided with a large arm, which is connected to a rocker arm via a middle arm. The other end of the rocker arm is connected to the welding head.

5. A method for repairing a waste boiler, characterized in that, Includes the following steps: Step 1: Using the waste boiler repair system according to any one of claims 1-4, inspect the waste boiler and mark the defective parts; Step 2: Remove defects with a depth of no more than 20mm. Grind the defect with a grinder to clean it. For defects with a depth greater than 20mm, clean the defect with a carbon arc gouging machine and grind it with a grinder to clean away slag and other debris. Perform MT testing on the ground area to check whether the defect has been cleaned and whether there are any other defects. Step 3: Hydrogen removal treatment. The entire equipment to be repaired is heated to about 350 degrees Celsius using heat treatment equipment and kept at 350 degrees Celsius for 24 hours. Step 4: Repair welding of defective parts. Before repair welding, preheat the welding area with electric heating. The preheating temperature is ≥150℃, and the interpass temperature is less than or equal to 200℃. Weld the defective parts according to the corresponding welding process. The equipment temperature is not lower than 300 degrees during the welding process. Step 5: Non-destructive testing of the repaired weld area. After the weld has cooled for 24 hours, the weld joint is subjected to 100% UT and MT testing. Step 6: Heat treatment. Stress relief heat treatment is performed on the entire weld seam between the tube sheet and the tube box using electric heating. Electric heating plates are required on both the inner and outer surfaces of the weld seam, and the internal heating plates are fixed with an annular ring. Step 7: Non-destructive testing of internal and external welds to determine whether the welds are complete.

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