A magnetic intelligent nondestructive testing device and method for nuclear power plant steel lining welds

Abstract

The present application relates to the field of nuclear engineering construction technology, and specifically to a magnetic intelligent non-destructive testing device and method for steel lining welds in nuclear power plants. The testing device includes a trolley body, a controller, a sealing mechanism, a vacuum device, a spraying mechanism, and an image acquisition mechanism; a magnetic suction mechanism is provided on the trolley body; the controller is provided on the trolley body; the sealing mechanism is movably connected to the trolley body, and the sealing mechanism has a sealing trough body; the vacuum device is provided on the trolley body and is connected to the sealing trough body; the spraying mechanism is provided on the trolley body and is controlled by the controller to spray the foaming agent; the image acquisition mechanism is provided on the trolley body and is controlled by the controller to collect the display image of the foaming agent bubbles in the inspection area. The present application can improve the detection efficiency, avoid non-destructive testing personnel from climbing high operations, reduce the safety risks of construction operations, and realize the technical innovation and application of automation, digitization, and intelligence of vacuum leak detection methods in the field of non-destructive testing of nuclear power plants.

Description

Technical Field

[0001] The present application relates to the technical field of nuclear engineering construction, and in particular to a magnetically intelligent nondestructive testing device and method for steel lining welds in nuclear power plants. Background Art

[0002] In the "Hualong One" project under construction, the steel lining has a larger pile type and a larger number of welds; in the field of nuclear power, it is necessary to detect the leakage of the steel lining butt welds. Previously, the commonly used detection method was the vacuum hood leak detection method, that is, to apply the display liquid in the area to be inspected, and then use the vacuum hood to seal the area to be inspected and evacuate the vacuum hood, and finally manually observe the foaming in the vacuum hood; this method is suitable for low-altitude environments, and through continuous human observation, the detection results have good credibility. However, for steel lining structures with larger pile types, the welds are longer and more numerous, and the position is higher, which requires continuous human high-altitude operations, and the labor intensity is high. The credibility of the detection results will be reduced, and the welds also involve curves. It is not easy for workers to adjust their positions at high altitudes, and the operation is difficult and risky. Summary of the invention

[0003] The present application provides a magnetic intelligent nondestructive testing device and method for steel lining welds in nuclear power plants, which utilizes an automated, digital integrated robot perspective to replace the manual operation and observation of conventional testing methods, realizes remote intelligent control through a control panel, identifies and analyzes leakage bubbles in the welds, and marks leakage points. The technical functions of the integrated robot device are used to reduce human involvement, and avoid the professional and technical difficulties of conventional vacuum leakage detection methods, such as difficulty in high-altitude operations, high risks, traceability of the testing process and data results, and low degree of review.

[0004] This application is implemented through the following technical solutions:

[0005] In a first aspect, the present application provides a magnetic intelligent nondestructive testing device for steel lining welds in nuclear power plants, comprising:

[0006] A trolley body, wherein a magnetic attraction mechanism is provided on the trolley body;

[0007] A controller, wherein the controller is arranged on the vehicle body;

[0008] A sealing mechanism, the sealing mechanism is movably connected to the trolley body and is controlled by the controller, and the sealing mechanism has a sealing groove body;

[0009] A vacuum device, which is arranged on the trolley body and communicated with the sealing tank body, and is controlled by the controller to suck the air in the sealing tank body;

[0010] A spraying mechanism, the spraying mechanism is arranged on the trolley body and is controlled by the controller to spray the foaming agent;

[0011] An image acquisition mechanism is disposed on the vehicle body and is controlled by the controller to collect an image of the foaming agent bubbles in the area to be inspected.

[0012] The magnetic intelligent nondestructive testing device for steel lining welds of nuclear power plants provided in the present application can enable the trolley body to automatically walk in a high-altitude state on the welds of steel lining wall panels of nuclear power plants by arranging a magnetic attraction mechanism on the trolley body, and then control the sealing mechanism and the vacuum equipment through the controller, so that the foaming agent applied by the spraying mechanism can be in a vacuum environment, and finally the image acquisition mechanism is used to collect the image of the foaming agent and identify the leakage bubbles in the image, so that it can automatically determine whether there is a leakage point at the weld position, thereby realizing the automatic detection of vacuum leakage of steel lining welds; compared with the conventional vacuum leakage detection method, it saves human resources, avoids the inspector's climbing operation, and greatly reduces the safety risk of the operation, the image acquisition mechanism can continuously observe and judge the foaming agent in real time, there is no problem of visual fatigue, and the entire detection process can be automatically converted into electronic image storage later, and the credibility of the detection result is stable and the traceability is strong.

[0013] In some optional embodiments, a marking mechanism is provided on the trolley body, and the marking mechanism is controlled by the controller to print a mark on the target object.

[0014] In some optional embodiments, the marking mechanism is slidably connected to the trolley body, and the marking mechanism is controlled by the controller to slide on the trolley body.

[0015] In some optional embodiments, the magnetic attraction mechanism is configured as a permanent magnet, wherein the position of the magnetic attraction mechanism on the trolley body is configured so that when the trolley body is located on the steel lining wall panel, there is a gap between the magnetic attraction mechanism and the steel lining wall panel.

[0016] In a second aspect, the present application provides a magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants, which is implemented based on any one of the magnetic intelligent nondestructive testing devices for steel lining welds in nuclear power plants described in the first aspect, and includes the following contents:

[0017] Apply foaming agent to the area of ​​the weld to be inspected;

[0018] Seal the area to be inspected so that the foaming agent is in a sealed space;

[0019] The sealed space is evacuated and images showing bubbles of the foaming agent in the sealed space are collected at intervals;

[0020] The leakage bubbles in the foaming agent bubble display image are identified and the weld leakage point is located based on the position of the leakage bubbles.

[0021] The magnetic intelligent nondestructive testing method for nuclear power plant steel lining welds provided in the present application can locate weld leakage points according to leakage bubbles by collecting foaming agent bubble display images and identifying leakage bubbles in the foaming agent bubble display images, thereby eliminating the need for human judgment, reducing the labor intensity of staff, and having high detection efficiency and accuracy.

[0022] In some optional embodiments, evacuating the sealed space includes the following steps:

[0023] Obtain the negative pressure value in the sealed space;

[0024] When the negative pressure value reaches a first threshold, the pressure in the sealed space is maintained for a first time period;

[0025] If no bubbles are generated in the sealed space, increase the negative pressure value in the sealed space;

[0026] When the negative pressure value reaches a second threshold value, the pressure in the sealed space is maintained for a second period of time.

[0027] In some optional embodiments, the images showing the bubbles of the foaming agent in the sealed space are continuously collected at a frame rate of 30 fps.

[0028] In some optional embodiments, identifying leakage bubbles in the foaming agent bubble display image and locating the leakage point based on the position of the leakage bubble includes the following:

[0029] Preprocessing the continuous frame foaming agent bubble display images;

[0030] Identify bubbles in each frame of the foaming agent bubble display image and determine whether it is a leakage display;

[0031] If the bubbles in the next frame of the foaming agent bubble display image are larger than those in the previous frame, the bubbles that gradually increase with the increase of the negative pressure in the sealed space are marked as leaking bubbles;

[0032] Locate the weld leak based on the location of the leak bubble.

[0033] In some optional embodiments, after identifying the bubbles in each frame of the foaming agent bubble display image, the following steps are also included:

[0034] Calculate the bubble area and perimeter;

[0035] If the bubble area and bubble perimeter in the last frame of the foaming agent bubble display image are equal to or larger than the bubble at the same position in the first frame of the foaming agent bubble display image, the bubble is marked as a leaking bubble;

[0036] The leak source is located based on the location of the leak bubble.

[0037] In some optional embodiments, preprocessing of the continuous frame foaming agent bubble display images includes removing noise using a median filter and enhancing image contrast using an adaptive threshold algorithm.

[0038] Compared with the prior art, this application has the following advantages and beneficial effects:

[0039] 1. The magnetic intelligent nondestructive testing device for steel lining welds of nuclear power plants provided by the present application can enable the trolley body to automatically walk in a high-altitude state on the welds of steel lining wall panels of nuclear power plants by arranging a magnetic attraction mechanism on the integrated all-in-one machine trolley body, and then control the sealing mechanism and the vacuum equipment through the controller, so that the foaming agent applied by the spraying mechanism can be in a vacuum environment, and finally the image acquisition mechanism is used to collect the image of the foaming agent bubble display and identify the leakage bubbles in the image, so that it can automatically determine whether there is a leakage point at the weld position, thereby realizing the automatic detection of vacuum leakage of steel lining welds; compared with the conventional vacuum leakage detection method, it saves human resources, avoids the inspector's climbing operation, and greatly reduces the safety risk of the operation. The image acquisition mechanism can continuously observe and judge the bubble situation of the HJ-Nulong leak detection foaming agent in real time, and there is no problem of visual fatigue. At the same time, the entire detection process can be automatically converted into electronic image storage later, and the credibility of the detection result is stable and the traceability is strong.

[0040] 2. The magnetic intelligent nondestructive testing method for nuclear power plant steel lining welds provided in the present application can locate weld leakage points based on leakage bubbles by collecting images displayed by foaming agent bubbles and identifying leakage bubbles in the images displayed by foaming agent bubbles, thereby eliminating the need for human judgment and reducing the labor intensity of testing personnel. The automated, digital, and intelligent innovative integrated testing equipment has a high testing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0042] Figure 1 A schematic diagram of the shaft side structure of the magnetic intelligent nondestructive testing device for steel lining welds of nuclear power plants provided in an embodiment of the present application, behind the housing of the trolley body;

[0043] Figure 2A schematic diagram of the front view of the structure of the housing of the trolley attached to the magnetic intelligent nondestructive testing device for the steel lining weld of a nuclear power plant provided in an embodiment of the present application;

[0044] Figure 3 A schematic flow chart of the intelligent magnetic nondestructive testing method for steel lining welds in nuclear power plants provided in an embodiment of the present application.

[0045] Marks and corresponding parts names in the attached drawings:

[0046] 1-trolley body, 2-controller, 3-sealing mechanism, 4-vacuum equipment, 5-spraying mechanism, 6-image acquisition mechanism, 7-power supply, 8-magnetic suction mechanism, 9-marking mechanism. DETAILED DESCRIPTION

[0047] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with examples and drawings. The illustrative implementation scheme of the present application and its description are only used to explain the present application and are not intended to limit the present application.

[0048] In the first aspect, the present application provides a magnetic intelligent nondestructive testing device for steel lining welds in nuclear power plants, such as Figure 1~Figure 2 As shown, the magnetic suction type intelligent nondestructive testing device for steel lining welds of nuclear power plants includes a trolley body 1, a controller 2, a sealing mechanism 3, a vacuum device 4, a spraying mechanism 5 and an image acquisition mechanism 6.

[0049] The trolley body 1 may include a base plate and running wheels arranged on the base plate. The base plate may be made of aluminum alloy sheet metal. A trolley body shell is arranged on the base plate to protect the structure, electrical components, etc. installed on the base plate. A driving mechanism and a power supply 7 are provided on the base plate. The power supply 7 may be set as a lithium battery. The driving mechanism cooperates with the running wheels to drive the running wheels, thereby realizing the movement of the trolley body 1. In actual implementation, the driving mechanism may be configured as a servo driving mechanism to ensure the movement accuracy of the trolley body 1, wherein the servo driver in the driving mechanism is connected to the controller 2 to be controlled by the controller 2 to work, and the servo driver cooperates with the servo motor to drive the running wheels to rotate; a magnetic attraction mechanism 8 is arranged on the trolley body 1, and the magnetic attraction mechanism 8 is controlled by the controller 2 to work, and the magnetic attraction mechanism 8 can be applied to the steel lining in the working state. The structure is attracted so that the running wheel is pressed on the steel lining wall panel structure. In actual implementation, the running wheel can be configured as a rubber wheel to prevent the steel lining wall panel parent material structure from being worn or scratched. At the same time, there is a large friction coefficient between the running wheel and the steel lining wall panel, so as to prevent the trolley body 1 from slipping during the movement. The position of the magnetic attraction mechanism 8 on the trolley body 1 is configured so that when the running wheel of the trolley body 1 contacts the steel lining wall panel, there is a gap between the magnetic attraction mechanism 8 and the steel lining wall panel, that is, the magnetic attraction mechanism 8 does not contact the steel lining wall panel, so as to prevent the magnetic attraction mechanism 8 from wearing or scratching the steel lining wall panel parent material structure. At the same time, no friction resistance is generated between the magnetic attraction mechanism 8 and the steel lining wall panel, and the traction force required for the trolley body 1 to move is smaller, which can save electric energy. Among them, the magnetic attraction mechanism 8 can use the strongest nepheline iron boron magnet as the magnetic unit, and an aluminum alloy shell is provided on the outside of the magnetic unit for protection.

[0050] The controller 2 is arranged on the trolley body 1, and the controller 2 is powered by a lithium battery. The lithium battery can adopt a DC48V, 20AH power supply. The lithium battery is detachably connected to the base plate for easy replacement and maintenance. The controller 2 can be configured as a programmable controller 2, a single-chip microcomputer, an embedded system, a field programmable gate array, etc. In actual implementation, the controller 2 can be configured as a microprocessor.

[0051] The sealing mechanism 3 is movably connected to the trolley body 1 and is controlled by the controller 2. The sealing mechanism 3 is used to provide a sealed environment for the foaming agent in the area to be inspected. The sealing mechanism 3 has a sealing groove. After the sealing mechanism 3 is controlled by the controller 2, the foaming agent in the area to be inspected can be enclosed in the sealing groove. In actual implementation, the sealing mechanism 3 may include a vacuum cover and a cylinder. The vacuum cover is connected to the bottom plate of the trolley body 1 through the cylinder. The cylinder is equipped with an action solenoid valve. The action solenoid valve is controlled by the controller 2 to act so that the cylinder can The vacuum hood is driven to move, and the internal groove body of the vacuum hood serves as a sealing groove body. When the vacuum hood is driven to move by the cylinder, the vacuum hood can enclose the foaming agent in the area to be inspected in the hood mouth so that the foaming agent is in a sealed environment. Taking into account the unevenness and curved surface structure at the weld, a flexible sealing body can be provided at the hood mouth of the vacuum hood. For example, a vacuum adsorption sponge can be installed on the hood mouth, so that the hood mouth can have sufficient fit with the uneven steel lining wall panel, thereby ensuring the sealing inside the vacuum hood after the vacuum hood contacts the steel lining wall panel and the steel lining weld.

[0052] The vacuum device 4 is arranged on the trolley body 1 and connected with the sealing groove body. The vacuum device 4 is controlled by the controller 2 to suck the air in the sealing groove body. Specifically, the vacuum device 4 can be configured as a vacuum tank, which is connected to the vacuum cover in the sealing mechanism 3 so that the sealing groove body is connected to the internal space of the vacuum tank. A solenoid valve controlled by the controller 2 and an adjustable pressure maintaining valve are arranged between the vacuum tank and the vacuum cover. A pressure gauge connected to the controller 2 is arranged in the vacuum cover or between the vacuum cover and the solenoid valve to monitor the air pressure in the vacuum cover in real time.

[0053] The spray mechanism 5 is arranged on the trolley body 1 and is controlled by the controller 2 to spray the foaming agent. The spray mechanism 5 can adopt a sprayer commonly used in the prior art. The spray mechanism 5 has a foaming agent storage tank for storing the foaming agent and a spray gun connected to the foaming agent storage tank. A hollow gravity ball negative pressure liquid suction system can be arranged inside the foaming agent, and an electromagnetic valve controlled by the action of the controller 2 can be arranged between the spray gun and the foaming agent storage tank.

[0054] The image acquisition mechanism 6 is arranged on the trolley body 1 and is controlled by the controller 2 to collect the display image of the foaming agent bubbles in the inspection area. The image acquisition mechanism 6 can be configured as a high-definition camera. In actual implementation, the vacuum cover can be configured as a transparent material to facilitate the image acquisition mechanism 6 to easily obtain the display image of the foaming agent bubbles, wherein the vacuum cover can be constructed to be transparent as a whole or partially transparent. In actual implementation, the number of image acquisition mechanisms 6 can be configured as two, one of which is used to collect the display image of the foaming agent bubbles, and the other can be connected to the bottom plate through a pan-tilt head to facilitate observation of the situation around the trolley body 1, realizing the automatic obstacle avoidance function. At the same time, when the pressure gauge is arranged outside the vacuum cover, the image acquisition mechanism 6 can monitor the pressure gauge to check whether the display value of the pressure gauge is consistent with the value fed back to the controller 2 by the pressure gauge.

[0055] The magnetic intelligent nondestructive testing device for steel lining welds of nuclear power plants provided in the embodiment of the present application can enable the trolley body 1 to walk on a high-altitude curved surface by arranging a magnetic attraction mechanism 8 on the trolley body 1, and then control the sealing mechanism 3 and the vacuum equipment 4 through the controller 2, so that the foaming agent applied by the spraying mechanism 5 can be in a vacuum environment, and finally the image acquisition mechanism 6 is used to capture the image of the foaming agent and identify the leakage bubbles in the image, so that it can automatically determine whether there is a leakage point at the location, thereby realizing automatic detection of weld leakage; compared with the usual detection method, it saves human resources, avoids high-altitude operations, and greatly reduces the operation risk. The image acquisition mechanism 6 can continuously observe the foaming agent bubbles, there is no problem of visual fatigue, and the credibility of the detection result is stable and the traceability is strong.

[0056] In some optional embodiments, a marking mechanism 9 is provided on the trolley body 1, and the marking mechanism 9 is controlled by the controller 2 to print a mark on the target object; the marking mechanism 9 mainly marks the corresponding position of the steel lining weld after the leakage point is detected, and the marking mechanism 9 can be configured as a laser printing device in the prior art, and can also be configured as a painting device; thereby, the staff can conveniently locate the leakage point when performing weld repair work, thereby improving work efficiency.

[0057] In some optional embodiments, the marking mechanism 9 is slidably connected to the trolley body 1, and the marking mechanism 9 is controlled by the controller 2 to slide on the trolley body 1. When a leak point is detected, the marking mechanism 9 can be controlled by the controller 2 to slide on the trolley body 1, so that the marking mechanism 9 can be aligned with the leak point, which is convenient for the staff to manually locate the specific position of the leak point.

[0058] In some optional embodiments, the magnetic attraction mechanism 8 is configured as a permanent magnet, which is independent of electrical energy and has a stable adsorption effect, thereby preventing the entire device from falling due to insufficient power.

[0059] In the second aspect, the embodiment of the present application provides a magnetic intelligent non-destructive testing method for a nuclear power plant steel lining weld, which is implemented based on any one of the magnetic intelligent non-destructive testing devices for a nuclear power plant steel lining weld described in the first aspect, and can be referred to Figure 3 , including the following:

[0060] S1. Apply foaming agent to the area of ​​the weld to be inspected.

[0061] The trolley body 1 can move on the steel lining wall panel in a stepping manner, that is, the trolley body 1 moves a fixed distance each time. Specifically, during two movements of the trolley, the overlapping distance of the two areas to be inspected is not less than 50 mm. During the movement of the trolley, the spray mechanism 5 can be controlled by the controller 2 to spray the foaming agent therein on the area to be inspected on the steel lining weld. The foaming agent can be a nuclear-grade special type of foaming agent, namely HJ-Nulong leak detection foaming agent.

[0062] S2. Seal the area to be inspected so that the foaming agent is in a sealed space.

[0063] When the amount of foaming agent in the area to be inspected meets the requirement, the controller 2 controls the sealing mechanism 3 to make the vacuum cover fit the steel lining wall and apply a certain pressure to ensure that the foaming agent is in the sealed space.

[0064] S3, evacuating the sealed space and collecting images of the bubbles of the foaming agent in the sealed space at intervals.

[0065] The vacuum device 4 is controlled by the controller 2 to make the vacuum tank evacuate the sealed space. During the evacuation process, the pressure in the vacuum cover is monitored by the pressure gauge. When the pressure gauge index reaches -0.02Mpa, the adjustable pressure-maintaining valve is controlled by the controller 2 to maintain the pressure of the vacuum cover for 10s, and then the vacuum cover is continuously evacuated. When the pressure gauge index reaches -0.06Mpa, the adjustable pressure-maintaining valve is controlled by the controller 2 to maintain the pressure of the vacuum cover for 30s. During the evacuation process, the image acquisition mechanism 6 continuously acquires the image display of the foaming agent bubbles. In actual implementation, the image of the foaming agent in the vacuum cover can be acquired at a frame rate of 30fps, and the acquired image can be stored in the controller 2 as a JPEG format file.

[0066] S4. Identify leakage bubbles in the foaming agent bubble display image and locate the weld leakage point based on the position of the leakage bubble.

[0067] Specific:

[0068] S41, preprocessing the continuous frame foaming agent bubble display image, including removing noise by using median filtering and enhancing image contrast by using an adaptive threshold algorithm. Preprocessing the image by using median filtering and an adaptive threshold algorithm can effectively improve the clarity and feature recognizability of the continuous frame foaming agent bubble display image, and can provide higher quality input data, thereby supporting more accurate algorithm decisions and more efficient image processing processes. Among them, the image can be converted into a binary image by using an adaptive threshold algorithm.

[0069] S42, identifying bubbles in each frame of the foaming agent bubble display image and counting the number of bubbles.

[0070] Image edge information is extracted through Canny edge detection, Sobel operator and other methods to assist in locating the bubble area; contours are extracted from binary images using tools such as OpenCV's findContours function; contours of suspected bubbles are screened out based on features such as size, shape, and roundness of the contours; and the fitEllipse or fitline function of OpenCV is used to perform circle fitting on the screened contours to identify bubbles.

[0071] S43, if the bubbles in the next frame of the foaming agent bubble display image are larger than those in the previous frame, the enlarged bubbles are marked as weld leakage bubbles.

[0072] During the vacuuming process, if there is a penetrating defect in the weld structure of the steel lining wall panel, the air will flow from the high-pressure side to the low-pressure side. Since there is a foaming agent in the sealed space, new bubbles will be generated in the sealed space. If new bubbles appear in the next frame of the foaming agent bubble display image and gradually increase with the increase of negative pressure in the vacuum cover, the bubbles can be identified as weld leakage bubbles.

[0073] S44. Locate the weld leakage point based on the position of the leakage bubble.

[0074] Of course, in the process of vacuuming, the original bubbles generated by brushing may be broken. For example, there are 10 bubbles in the sealed space initially. During the vacuuming process, a new bubble is generated due to a weld defect, and the bubbles in the sealed space initially may be broken. This may result in the number of bubbles in the previous frame of the foaming agent bubble display image being 10, while the number of bubbles in the next frame of the foaming agent bubble display image is also 10, and the controller 2 will make a misjudgment. Therefore, in some optional embodiments, after the bubbles in each frame of the foaming agent bubble display image are identified, the following contents are also included:

[0075] S421. Calculate the bubble area and perimeter.

[0076] S422: If the bubble area and bubble perimeter in the last frame of the foaming agent bubble display image are equal to or larger than the bubble at the same position in the first frame of the foaming agent bubble display image, mark the bubble as a leaking bubble.

[0077] During the vacuuming process, if the bubbles are not replenished with air, the bubbles will become smaller and smaller. However, the air in the bubbles generated by defects can be replenished, and their size can be maintained or gradually increased. When the number of bubbles does not change, the size of the bubbles in the foaming agent bubble display image before and after can be compared to further determine the leakage bubbles and avoid misjudgment.

[0078] During the actual detection process, the foaming agent bubble display image can also be uploaded to the terminal through the controller 2, for example, it can be uploaded to the cloud, mobile phone, computer, notebook and other devices that can express images, and the tester can manually record the leakage bubbles for verification.

[0079] S423. Locate the weld leakage point based on the position of the leakage bubble.

[0080] The magnetic intelligent nondestructive testing method for nuclear power plant steel lining welds provided in the present application can locate weld leakage points according to leakage bubbles by collecting foaming agent bubble display images and identifying leakage bubbles in the foaming agent bubble display images, thereby eliminating the need for human judgment, reducing the labor intensity of staff, and having high detection efficiency.

[0081] The above specific embodiments illustrate the implementation methods of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with some embodiments, this does not mean that the features of this application are limited to the implementation methods. On the contrary, the purpose of introducing the application in conjunction with the implementation methods is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide an in-depth understanding of the present application, the above description contains many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0082] It should be noted that in this specification, similar numbers and letters represent similar items in the above drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of this application, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0083] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants, characterized in that: It is based on the magnetic intelligent non-destructive testing device for the steel lining weld of the nuclear power plant. The device includes: A trolley body (1), wherein a magnetic attraction mechanism (8) is provided on the trolley body (1); A controller (2), the controller (2) being arranged on the trolley body (1); A sealing mechanism (3), the sealing mechanism (3) being movably connected to the trolley body (1) and being controlled by the controller (2), the sealing mechanism (3) comprising a sealing groove; A vacuum device (4), the vacuum device (4) being arranged on the trolley body (1) and being connected to the sealing groove body, the vacuum device (4) being controlled by the controller (2) to suck the air in the sealing groove body; A spraying mechanism (5), the spraying mechanism (5) being arranged on the trolley body (1) and being controlled by the controller (2) to spray the foaming agent; An image acquisition mechanism (6), the image acquisition mechanism (6) being arranged on the trolley body (1) and being controlled by the controller (2) to acquire an image of bubbles of the foaming agent in the area to be inspected; The method comprises the following steps: Apply foaming agent to the area of ​​the weld to be inspected; Seal the area to be inspected so that the foaming agent is in a sealed space; The sealed space is evacuated and images of bubbles of the foaming agent in the sealed space are collected at intervals. During the evacuation process, the pressure in the vacuum cover is monitored by a pressure gauge. When the pressure gauge index reaches -0.02 Mpa, the adjustable pressure-maintaining valve is controlled by the controller (2) to maintain the pressure of the vacuum cover for 10 seconds, and then the vacuum cover is continuously evacuated. When the pressure gauge index reaches -0.06 Mpa, the adjustable pressure-maintaining valve is controlled by the controller (2) to maintain the pressure of the vacuum cover for 30 seconds. Identify leakage bubbles in the foaming agent bubble display image and locate the weld leakage point based on the position of the leakage bubble; Among them, identifying the leakage bubbles in the foaming agent bubble display image and locating the weld leakage point based on the position of the leakage bubbles includes the following: Preprocessing the continuous frame foaming agent bubble display images; Identify bubbles in each frame of the foaming agent bubble display image and count the number of bubbles to determine whether it is a leakage display; If the bubbles in the next frame of the foaming agent bubble display image are larger than those in the previous frame, the bubbles that gradually increase with the increase of the negative pressure in the sealed space are marked as leaking bubbles; Locate and mark the weld leak point based on the position of the leak bubble; Among them, after identifying the bubbles in each frame of the foaming agent bubble display image, the following contents are also included: Calculate the bubble area and perimeter; If the bubble area and bubble perimeter in the last frame of the foaming agent bubble display image are equal to or larger than the bubble at the same position in the first frame of the foaming agent bubble display image, the bubble is marked as a leaking bubble; Locate the weld leak based on the location of the leak bubble; Among them, during the two travels of the trolley, the overlapping distance of the two areas to be inspected shall not be less than 50mm.

2. The magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants according to claim 1 is characterized in that: The trolley body (1) is provided with a marking mechanism (9), and the marking mechanism (9) is controlled by the controller (2) to print a mark on the target object.

3. The magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants according to claim 2 is characterized in that: The marking mechanism (9) is slidably connected to the trolley body (1), and the marking mechanism (9) is controlled by the controller (2) to slide on the trolley body (1).

4. The magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants according to claim 1 is characterized in that: The magnetic attraction mechanism (8) is configured as a permanent magnet, wherein the position of the magnetic attraction mechanism (8) on the trolley body (1) is configured such that when the trolley body (1) is located on the steel lining wall plate, there is a gap between the magnetic attraction mechanism (8) and the steel lining wall plate.

5. The magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants according to claim 1 is characterized in that: The following are included when vacuuming a sealed space: Obtain the negative pressure value in the sealed space; When the negative pressure value reaches a first threshold, the pressure in the sealed space is maintained for a first time period; If no bubbles are generated in the sealed space, increase the negative pressure value in the sealed space; When the negative pressure value reaches a second threshold value, the pressure in the sealed space is maintained for a second period of time.

6. The magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants according to claim 1 is characterized in that: The images showing the bubbles of the foaming agent in the sealed space are continuously collected at a frame rate of 30fps.

7. The magnetic intelligent nondestructive testing method for steel lining welds in nuclear power plants according to claim 1 is characterized in that: The preprocessing of the continuous frame foaming agent bubble display images includes removing noise using median filtering and enhancing image contrast through an adaptive threshold algorithm.

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