A sealing surface cleaning, inspection and defect measurement device for use in radioactive environments

Abstract

The present invention discloses a sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment, comprising a traveling mechanism, wherein the traveling mechanism comprises a vehicle chassis, one end of which is provided with a driving system, and the vehicle chassis is also provided with a sealing surface cleaning module or an inspection and defect measurement module. The beneficial effect is that the device can effectively replace the existing manual operation mode, effectively reduce the radiation dose of personnel and improve the cleaning efficiency, avoid the blind spot of human eye inspection, and obtain three-dimensional visualization data of the sealing surface quality of the top cover. At the same time, the defect position can be located and the size can be measured, providing a reliable basis for defect judgment to ensure the integrity of the pressure boundary of a circuit.

Description

Technical Field

[0001] The present invention belongs to the field of on-site maintenance of nuclear power plants, and specifically relates to a sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment, which can execute and complete multiple tasks such as automatic cleaning of the top cover sealing surface, video inspection and three-dimensional defect measurement. Background Art

[0002] The reactor pressure vessel is mainly composed of the vessel body and the top cover, which are connected by multiple main bolts and sealed with two inner and outer sealing rings. The pressure vessel sealing ring, the top cover sealing groove, and the vessel flange sealing surface together form the primary circuit pressure boundary.

[0003] Due to the peculiarity of the nuclear field, as the operation time of the unit increases, the pressure vessel top cover has extremely high radioactivity. At present, the cleaning and inspection of the pressure vessel top cover sealing groove of the existing pressurized water reactor units are all completed manually by maintenance personnel. During the overhaul, the pressure vessel top cover needs to be hoisted and stored on the legs of the top cover storage room, and the cleaning and inspection of the sealing groove must be completed during the low water level period. The cleaning and inspection of the top cover sealing groove is time-consuming. The maintenance personnel need to maintain a squatting posture for a long time during the entire work process and are in a high-irradiation environment. They will be exposed to a large radiation dose and have the risk of body surface contamination. During the cleaning and inspection process of the personnel, if the cleaning is not in place or the sealing surface defects are not discovered, it may also cause the pressure vessel seal to fail, resulting in the overhaul retreat mode and delaying the overhaul main line time, seriously affecting the economic benefits of the power plant.

[0004] At present, there is no such equipment in China, and the cleaning and inspection of the top cover sealing surface rely on manual work. The existing top cover sealing surface cleaning equipment abroad only has simple cleaning and inspection functions, and no sealing surface defect identification and measurement functions. In addition, the positioning accuracy of the equipment is affected by the top cover hoisting storage position and the track preset position accuracy, and there is no positioning compensation related function, so the practicality is poor. Summary of the invention

[0005] The purpose of the present invention is to provide a sealing surface cleaning, inspection and defect measurement device in a radioactive environment, which can effectively replace the existing manual operation mode, effectively reduce the radiation dose of personnel and improve the cleaning efficiency, avoid the blind spot of human eye inspection, and obtain three-dimensional visualization data of the sealing surface quality of the top cover. At the same time, the defect position can be located and the size can be measured, providing a reliable basis for defect judgment to ensure the integrity of the pressure boundary of the primary circuit.

[0006] The technical solution of the present invention is as follows: a sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment, comprising a traveling mechanism, wherein the traveling mechanism comprises a vehicle chassis, a driving system is provided at one end of the vehicle chassis, and a sealing surface cleaning module or an inspection and defect measurement module is also provided on the vehicle chassis.

[0007] Wheels are installed at the bottom of the vehicle chassis.

[0008] A guide wheel mechanism is provided on the vehicle chassis, and the guide wheel mechanism can prevent the device from tipping over.

[0009] The vehicle chassis is provided with a rotational compensation, the rotational compensation is provided with a radial compensation, the radial compensation is provided with a top mounting platform, the radial compensation is provided with a downward pressure mechanism, a window is opened in the middle of the top mounting platform, and the top mounting platform is provided with a sealing surface cleaning module or an inspection and defect measurement module.

[0010] Functional components are installed on the window of the top mounting platform. The top mounting platform and the functional components serve as the mounting platform for cleaning, video inspection, and defect measurement modules and are kept in contact with the top cover sealing surface through a pre-tightening spring. Travel wheels and guide wheels are provided on the top mounting platform. The travel wheels are in contact with the top cover flange and are kept in contact. The guide wheels are removed into the top cover sealing groove for precise guiding. A cleaning brush and a steam nozzle are installed in the functional component. Video monitoring modules are installed at both ends of the top mounting platform to monitor the sealing surface condition.

[0011] A vehicle body cleaning control box is arranged on one side of the vehicle body chassis, and a steam module and a waste liquid collection box are stacked up and down and arranged on the side of the vehicle body cleaning control box.

[0012] The radial compensation is provided with an X-axis slide rail and a Y-axis slide rail, a laser three-dimensional measurement module is installed on the Y-axis slide rail, and the laser three-dimensional measurement module can move on the X-axis slide rail and the Y-axis slide rail.

[0013] A video inspection module is provided at one end of the top mounting platform.

[0014] The four corners on the radial compensation are mounted with a top mounting platform via preloaded springs.

[0015] The beneficial effects of the present invention are: it can realize walking and positioning in a narrow space (the equipment realizes circular motion between the legs of the top cover storage room and the cement shielding wall, and the maximum radial width does not exceed 250mm), and has an integrated design with multiple functions such as top cover sealing surface cleaning, inspection and defect measurement; modular structure, through module replacement and adjustment, it can be applied to pressure vessel top covers of different sizes of each unit; lightweight design, the device body is made of lightweight aluminum alloy material; it has automatic mode and manual mode, and the mode can be switched remotely; the material in contact with the top cover surface is made of non-metallic material to prevent damage to the sealing surface; it has a radial positioning compensation function to ensure accurate alignment with the pressure vessel top cover sealing groove; it has a fitting function with the sealing groove to compensate for height direction errors; the high radiation resistance video inspection module can automatically identify suspected defects; it has a circumferential position calibration function to automatically locate the defect position; it has a defect three-dimensional modeling function, and can measure the defect size; it has a cleaning spray function to enhance the cleaning effect; it has a waste liquid recovery function to prevent the spread of radioactive waste; it has an anti-tipping function design. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of a sealing surface cleaning module in a sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment provided by the present invention;

[0017] Figure 2 This is a schematic diagram of an inspection and defect measurement module in a sealing surface cleaning, inspection and defect measurement device in a radioactive environment provided by the present invention.

[0018] In the figure: 1 control box, 2 steam module, 3 waste liquid collection box, 4 guide wheel mechanism, 5 vehicle chassis, 6 pressing mechanism, 7 rotation compensation mechanism, 8 radial compensation mechanism, 9 driving system, 10 preload spring, 11 video monitoring module, 12 top mounting platform, 13 functional component, 14 cleaning brush, 15 steam nozzle, 16 walking wheel, 17 guide wheel, 18 X-axis slide rail, 19 Y-axis slide rail, 20 video inspection module, 21 laser 3D measurement module. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] A sealing surface cleaning, inspection and defect measurement device for use in radioactive environments is made of lightweight aluminum alloy material and has a modular design. The module can be replaced to be suitable for pressure vessel top cover sealing surfaces of different sizes.

[0021] like Figure 1-2As shown, a sealing surface cleaning, inspection and defect measurement device in a radioactive environment includes a traveling mechanism, which includes a vehicle chassis 5, a driving system 9 is installed at one end of the vehicle chassis 5, a wheel is installed at the bottom of the vehicle chassis 5, and a guide wheel mechanism 4 is provided on the vehicle chassis 5, which can prevent the device from tipping over. The vehicle chassis 5 is also provided with a sealing surface cleaning module and an inspection and defect measurement module.

[0022] A rotation compensation 7 is installed on the chassis 5 of the vehicle body, and a radial compensation 8 is installed on the rotation compensation 7. A top mounting platform 12 is installed on the four corners of the radial compensation 8 through a preload spring 10. A downward pressing mechanism 6 is also provided on the radial compensation 8. A window is opened in the middle of the top mounting platform 12, and a functional component 13 is installed on the window. The top mounting platform 12 and the functional component 13 are used as mounting platforms for cleaning, video inspection, and defect measurement modules, and are kept in contact with the top cover sealing surface through the preload spring 10. A running wheel 16 and a guide wheel 17 are provided on the top mounting platform 12. The running wheel 16 is in contact with the top cover flange to keep in contact, and the guide wheel 17 is removed into the top cover sealing groove for precise guidance. A cleaning brush 14 and a steam nozzle 15 are installed in the functional component 13. Video monitoring modules 11 are installed at both ends of the top mounting platform 12 to monitor the sealing surface condition.

[0023] Before the device is installed, the preload spring 10 is compressed by the pressing mechanism 6 and released after the device is in place.

[0024] In order to solve the positioning error problem between the track below the equipment and the sealing surface of the top cover, the cleaning car body control box 1 is set on the left side, and the steam module 2 and the waste liquid collection box 3 are stacked up and down on the side, which can enhance the cleaning effect and avoid the spread of radioactive waste liquid. The video inspection and defect measurement car body has the same structure as the cleaning car body.

[0025] The radial compensation 8 may also be provided with an X-axis slide rail 18 and a Y-axis slide rail 19, on which a laser three-dimensional measurement module 21 is installed, and the laser three-dimensional measurement module 21 can move on the X-axis slide rail 18 and the Y-axis slide rail 19. A video inspection module 20 is provided at one end of the top mounting platform 12.

[0026] The specific working process of the present invention is as follows:

[0027] Cleaning function:

[0028] 1 The preload spring 10 is compressed by the pressing mechanism 6, the cleaning trolley is installed on the track, and the guide wheel mechanism 4 is locked to prevent the device from tipping over.

[0029] 2 After the guide wheel 17 and the cleaning brush 14 are inserted into the sealing groove of the pressure vessel, release the preload spring 10.

[0030] 3 The cleaning trolley automatically runs, the steam nozzle 15 releases steam to dissolve the dirt on the sealing surface, and the cleaning brush 14 moves to clean the sealing surface. The video monitoring module 11 monitors the status of the sealing surface before and after cleaning in real time.

[0031] 4 The drive system 9 performs circumferential motion to clean the sealing surface. During this period, the rotation compensation 7 and radial compensation 8 mechanisms compensate for positioning errors during the cleaning process.

[0032] 5 After all cleaning work is completed, the preload spring 10 is compressed by the pressing mechanism 6 and the cleaning trolley is removed.

[0033] Video inspection and defect measurement functions:

[0034] 1 Compress the preload spring 10 through the pressing mechanism 6, install the video inspection and defect measurement trolley on the track, and lock the guide wheel mechanism 4 to prevent the device from tipping over.

[0035] 2 After the guide wheel 17 and the cleaning brush 14 are inserted into the sealing groove of the pressure vessel, release the preload spring 10.

[0036] 3 Video inspection and defect measurement The trolley automatically moves in a circumferential direction, and the cleaning quality of the sealing surface is inspected and stored through the video inspection module 20, while suspected defects are automatically identified and the defect coordinates are located.

[0037] 4 After the video inspection is completed, the trolley automatically locates and moves to the suspected defect coordinates. The laser 3D measurement module 21 accurately locates the suspected defect through the X-axis slide rail 18 and the Y-axis slide rail 19 and performs laser 3D reconstruction, and displays and records the defect data.

[0038] 5 After all video inspection and defect measurement work is completed, the preload spring 10 is compressed by the pressing mechanism 6, and the video inspection and defect measurement trolley is removed.

[0039] The present invention has been successfully applied to the cleaning, inspection and defect measurement of the existing reactor pressure vessel top cover sealing surface, successfully replacing the existing manual operation method, effectively reducing the radiation dose of personnel and improving the cleaning efficiency. The top cover sealing surface inspection obtains visual data storage to avoid missed inspections due to human errors. At the same time, it can automatically identify and locate the defect position for three-dimensional model reconstruction and size measurement, providing a reliable basis for defect judgment, ensuring the integrity of the primary circuit pressure boundary, and improving the safety and economic benefits of the power plant, with significant results.

Claims

1. A sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment, characterized in that: It includes a running mechanism, wherein the running mechanism includes a vehicle chassis, one end of which is provided with a driving system, and the vehicle chassis is also provided with a sealing surface cleaning module or an inspection and defect measurement module; Wheels are installed at the bottom of the vehicle chassis; The vehicle chassis is provided with a guide wheel mechanism, which can prevent the device from tipping over; The vehicle chassis is provided with a rotation compensation, the rotation compensation is provided with a radial compensation, the radial compensation is provided with a top mounting platform, the radial compensation is provided with a pressing mechanism, a window is opened in the middle of the top mounting platform, and the top mounting platform is provided with a sealing surface cleaning module or an inspection and defect measurement module; The four corners of the radial compensation are equipped with a top mounting platform through preloaded springs; Functional components are installed on the window of the top mounting platform. The top mounting platform and the functional components serve as the mounting platform of the cleaning, inspection and defect measurement modules and are kept in contact with the top cover sealing surface through a pre-tightening spring. Travel wheels and guide wheels are provided on the top mounting platform. The travel wheels are in contact with the top cover flange and are kept in contact. The guide wheels are inserted into the top cover sealing groove for precise guiding. A cleaning brush and a steam nozzle are installed in the functional component. Video monitoring modules are installed at both ends of the top mounting platform to monitor the sealing surface condition.

2. A sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment as claimed in claim 1, characterized in that: A vehicle body cleaning control box is arranged on one side of the vehicle body chassis, and a steam module and a waste liquid collection box are stacked up and down and arranged on the side of the vehicle body cleaning control box.

3. The sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment according to claim 1, characterized in that: The radial compensation is provided with an X-axis slide rail and a Y-axis slide rail, a laser three-dimensional measurement module is installed on the Y-axis slide rail, and the laser three-dimensional measurement module can move on the X-axis slide rail and the Y-axis slide rail.

4. The sealing surface cleaning, inspection and defect measurement device for use in a radioactive environment according to claim 1, characterized in that: A video inspection module is provided at one end of the top mounting platform.

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