Universal method capable of automatically generating end socket welding seam X-ray detection point location
By automatically generating X-ray inspection points for end cap welds using image processing technology, the problems of complex manual operation and insufficient accuracy are solved, achieving efficient and accurate automatic inspection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHONGQING UNICOMP TECH CO LTD
- Filing Date
- 2026-01-28
- Publication Date
- 2026-04-17
AI Technical Summary
Existing technologies rely on manual visual inspection for X-ray inspection of head welds, resulting in a high risk of missed defects, complex and time-consuming operations, and low efficiency, especially in customized head inspections.
The head is rotated 360 degrees to collect attitude data, and a proportional head contour image is drawn. Image processing technology is used to extract the weld contour coordinates, automatically generate X-ray detection points, and calculate the rotation angle and movement coordinates of the detector and the X-ray source to achieve automatic detection.
It significantly improves the efficiency and accuracy of point generation, reduces manual intervention, enhances the intelligence and accuracy of detection, and avoids the cumbersome operations of traditional methods.
Smart Images
Figure CN121883476A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of detection technology, and in particular to a general method for automatically generating X-ray inspection points for end cap welds. Background Technology
[0002] With the continuous development of testing technology, X-ray non-destructive testing has been widely used for the quality inspection of welds on pressure vessel heads. This method involves emitting X-rays through an X-ray tube, which penetrates the weld. The transmitted signal is received by a detector and converted into a digital image by electrons, allowing inspectors to determine whether the weld is qualified.
[0003] Currently, the commonly used inspection method relies on a general point-to-point programming approach. The inspector must enter the lead room before each inspection point, manually adjust the detector's rotation angle, visually determine the tangent position between the detector and the weld, measure the distance between the detector and the weld, and then move the detector to an equidistant position. After confirmation, the point information is saved, and the above operations are repeated point by point to generate a point program, which is then sent to the controller. The controller drives the hardware to complete the automatic inspection. This method has the following drawbacks: it relies on manual visual confirmation, which can easily lead to missed defects and poses a risk of equipment collision; each inspection point requires manual adjustment, which is time-consuming, especially in the inspection of customized heads where different sizes and multiple welds are distributed, requiring reprogramming and being particularly time-consuming; and the repeated adjustment of the detector's rotation angle and equidistant position from the weld makes the operation complex.
[0004] Therefore, there is an urgent need for a universal and automatic method to generate inspection points for head welds, in order to improve the efficiency and accuracy of point coordinate generation, reduce manual intervention, reduce the risk of missed inspections, and enhance the overall intelligence level of inspection. Summary of the Invention
[0005] The purpose of this invention is to provide a general method for automatically generating X-ray inspection points for end cap welds, aiming to solve the problems of implementation difficulties and insufficient accuracy in the point editing process.
[0006] To achieve the above objectives, the present invention provides a general method for automatically generating X-ray inspection points for end cap welds, comprising the following steps:
[0007] The head is rotated 360 degrees to collect attitude data, and a proportional head outline image is drawn. The number of regular and irregular welds, weld type, actual weld length and product perimeter are input.
[0008] Process regular weld types and irregular weld types, extract the outline points of the side view and top view of the regular weld type and the irregular weld type respectively, and calculate the weld length and angle of the regular weld type and the irregular weld type;
[0009] Calculate the starting and ending points of the regular weld type and the irregular weld type respectively, and calculate the slope of the regular perpendicular line passing through the endpoint between the starting and ending points and the slope of the irregular perpendicular line.
[0010] The rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source are calculated based on the slope of the regular vertical line and the slope of the irregular vertical line, respectively.
[0011] The true physical relative coordinates of the detector and the X-ray source are restored based on the magnification of the image and the actual weld.
[0012] The regular weld types include regular longitudinal welds and regular circumferential welds.
[0013] Specifically, the processing of regular and irregular weld types involves extracting the contour points of the side and top views of the regular and irregular weld types, respectively, and calculating the weld length and angle of the regular and irregular weld types as follows:
[0014] For regular weld types, extract the contour points of the side and top views of the regular weld type, and calculate the weld length and angle;
[0015] For irregular weld types, extract the contour points of the side and top views of the irregular weld type, and calculate the weld length and angle.
[0016] Specifically, the following methods are used to calculate the starting and ending points of the regular weld type and the irregular weld type, and to calculate the slopes of the regular and irregular perpendicular lines passing through the endpoints between the starting and ending points:
[0017] Calculate the start and end points of the regular weld type, and calculate the slope of the regular perpendicular line passing through the end point between the start and end points;
[0018] Calculate the starting and ending points of the irregular weld type, and calculate the slope of the irregular vertical line passing through the endpoint between the starting and ending points.
[0019] The specific methods for calculating the rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source based on the slope of the regular vertical line and the slope of the irregular vertical line are as follows:
[0020] The rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source are calculated based on the slope of the vertical line described above.
[0021] The rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source are calculated based on the slope of the irregular vertical line.
[0022] This invention provides a general method for automatically generating X-ray inspection points for head welds. The method involves rotating the head 360 degrees to collect attitude data, drawing a scaled-down outline image of the head, and inputting the number of regular and irregular welds, weld type, actual weld length, and product perimeter. The method processes the regular and irregular weld types, extracting the side and top view outline points for each type, and calculating the weld length and angle. Finally, it calculates the starting and ending points for each type of weld, and then calculates the relationship between the starting point and the end point. The method calculates the slopes of regular and irregular perpendicular lines passing through the endpoints between beam points; it also calculates the rotation angle, coordinate offset, and bottom rotation angle between the detector and the X-ray source based on the slopes of the regular and irregular perpendicular lines; and it restores the true physical relative coordinates between the detector and the X-ray source based on the magnification of the image and the actual weld. This method uses images of the head weld dimensions (top and side views) and extracts the contour coordinates of the head and its weld using image processing technology. The image pixel information is converted into a geometric model, and finally, through corresponding calculations, the coordinates of the X-ray detection points of the head weld are obtained. This method can meet the detection requirements of welds on most spherical heads. This method first obtains the weld distribution from the top-view image. The magnification ratio is then determined by comparing the actual size of the end cap with the pixel size in the image to obtain the distribution of each weld in the top view. Next, a corresponding detection coordinate system is established for each weld in the side view. The optimal detection coordinates and angles for welds of different lengths and types in the image are calculated. Finally, the coordinates in the image are transformed to the actual detection coordinate system using the magnification ratio. The end cap is placed on a 360-degree rotating mechanism for detection. The detector and X-ray source are always on the same plane, and each axis works in coordination during detection. This method automatically generates X-ray detection points using the dimensional images of the end cap welds (side and top views), avoiding the tedious manual point-by-point editing of traditional methods. This significantly improves the efficiency of point generation. The generated point information can automatically calculate the rotation angle required for the detector / X-ray source to be tangent to the weld and the movement coordinates at that angle. Compared to manual observation, this method is simple to operate, has high positioning accuracy, and good versatility, ensuring the accuracy and reliability of subsequent X-ray flaw detection. It effectively solves the implementation difficulties and insufficient accuracy problems in the point editing process. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0024] The terms "first," "second," "third," and "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.
[0025] It should be noted that all information (including but not limited to user device information, user personal information, etc.), data (including but not limited to data used for analysis, stored data, displayed data, etc.), and signals involved in this application have been authorized by the user or fully authorized by all parties, and the collection, use, and processing of related data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. For example, the strain data, acceleration data, displacement data, pressure data, and video data involved in this application were all obtained with full authorization.
[0026] Figure 1 This is a flowchart of a general method for automatically generating X-ray inspection points for end cap welds, provided by the present invention.
[0027] Figure 2 This is a schematic diagram of the X-ray source, detector, and weld to be inspected during a specific inspection process according to the present invention.
[0028] Figure 3 This is an example diagram of a regular weld seam present on the end cap in this invention, including a side view and a top view.
[0029] Figure 4 This is an example diagram of an irregular weld seam on the end cap in this invention, including a side view and a top view.
[0030] Figure 5 This is a schematic diagram of each point to be calculated in the side view and top view of the regular weld in this invention.
[0031] Figure 6 This is a schematic diagram illustrating the inspection sequence of regular weld seams on the end cap in this invention.
[0032] Figure 7 This is a schematic diagram showing the angle to be calculated and the bottom length of the irregular weld seam on the end cap in this invention. Detailed Implementation
[0033] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.
[0034] Please see Figures 1-7 The present invention provides a general method for automatically generating X-ray inspection points for end cap welds, comprising the following steps:
[0035] The S1360-degree rotating head collects attitude data, draws a proportional head outline image, and inputs the number of regular and irregular welds, weld type, actual weld length, and product perimeter.
[0036] In this embodiment of the invention, the regular weld seam includes two types: regular longitudinal weld seam and regular circumferential weld seam, while the irregular weld seam has only one type.
[0037] S2 processes regular and irregular weld types, extracts the side and top view contour points of the regular and irregular weld types respectively, and calculates the weld length and angle of the regular and irregular weld types;
[0038] Specific methods:
[0039] S21 processes regular weld types, extracts the side and top view contour points of the regular weld type, and calculates the weld length and angle;
[0040] S22 processes irregular weld types, extracts the contour points of the side view and top view of the irregular weld type, and calculates the weld length and angle.
[0041] S3 calculates the starting and ending points of the regular weld type and the irregular weld type respectively, and calculates the slope of the regular perpendicular line passing through the endpoint between the starting point and the ending point and the slope of the irregular perpendicular line.
[0042] Specific methods:
[0043] S31 calculates the start and end points of the regular weld type, and calculates the slope of the regular perpendicular line passing through the end point between the start and end points;
[0044] S32 calculates the starting and ending points of the irregular weld type, and calculates the slope of the irregular vertical line passing through the endpoint between the starting and ending points.
[0045] S4 calculates the rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source based on the slope of the regular vertical line and the slope of the irregular vertical line, respectively.
[0046] Specific methods:
[0047] S41 calculates the rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source based on the slope of the vertical line described above.
[0048] S42 calculates the rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source based on the slope of the irregular vertical line.
[0049] S5 restores the true physical relative coordinates of the detector and the X-ray source based on the magnification of the image and the actual weld seam.
[0050] To better understand this technical solution, the following embodiments are provided for further explanation:
[0051] 1. Draw dimensional images of the head weld from the side and top views. Using CAD or other drawing software, draw a scaled-down outline of the head's external contour from the side view and a scaled-down outline of the external contour and weld from the top view. These must be consistent with the actual weld distribution, with one end of the longitudinal weld located at the far right of the top view, and the remaining weld ends arranged counter-clockwise. This ensures the accuracy and logical consistency of the software calculations. Examples of regular and irregular welds are listed below, such as... Figure 3 , 4 As shown:
[0052] 2. Input the number of regular welds and irregular welds, as well as the corresponding weld type, actual weld length, product perimeter, and other information (regular welds include regular longitudinal welds and regular circumferential welds, while irregular welds have only one type).
[0053] 3. After binarizing the image (processed according to Formula 1, assuming the original image is s, and y and x are the number of rows and columns respectively), the contour binarized images g of the side view and top view can be obtained.
[0054] Formula 1:
[0055] Here, thresh is the threshold, which is usually set to 128.
[0056] 4. Apply contour extraction methods from image processing algorithms to the binarized image g, referring to Formula 2 (traverse the image pixels, where a foreground white pixel is adjacent to a black pixel, or a black pixel is adjacent to a white pixel). (Indicates that adjacent points satisfy the 8-neighborhood relationship) Extract the contour of g. Based on the different positions of the contour points, the side view contour g1 and the top view contour g2 can be obtained.
[0057] Formula 2:
[0058] 5. First, process the top view g2. The outermost circular pixels are now known. By calculating the sum of the distances between points sequentially according to Formula 3, the perimeter of the outer contour in pixels can be obtained. .
[0059] Formula 3:
[0060]
[0061] VI. The actual circumference of the bottom of the end cap can be obtained through actual measurement. Formula 4 can be used to obtain the magnification ratio between the actual size and the pixel size. The value of .
[0062] Formula 4:
[0063] VII. For regular weld treatment, both the side view and top view are drawn to scale from the same header; therefore, Figure 3 In the middle, lm equals af, and ab equals ln length. The position of point n can be obtained from the length of ab and point l. Draw a perpendicular line from point n to lm and intersect it with the outer contour of the side view at point p. The annular area of the head where point p is located is the area where the circumferential weld is located.
[0064] 8. In the top-view contour diagram g2, use the opening and closing operations in image processing technology (Formula 5 represents the structuring element b, and Formula 6 is the opening and closing operation formula) to find the positions of each intersecting point (a, b, c, d, e, f, g, h), and calculate the lengths of ef, gh, ab, and cd, as well as the relative horizontal angle information A_ef, A_gh, A_ab, and A_cd (angle range 0-360 degrees). After rotating each longitudinal weld by the corresponding angle, it will be located in a horizontal position, such as... Figure 5 As shown.
[0065] Formula 5:
[0066] Formula 6:
[0067] 9. In the test profile g1, obtain all points of the profile. After sorting, the contour points between points lp are obtained. The pixel distance between lp can be calculated using Formula 7. .
[0068] Formula 7:
[0069] 10. Given the number of regular welds and the respective numbers and distributions of regular longitudinal and circumferential welds, inspect them sequentially, first inspecting the longitudinal welds, then the circumferential welds. Figure 6 As shown.
[0070] 11. The distance d between the detector and the weld cross-section, the focal length f between the detector and the optical tube, and the width w of the detector's imaging area are known conditions. Based on the properties of similar triangles, the weld length r that the detector can detect is calculated, as shown in Formula 8.
[0071] Formula 8:
[0072] 12. The actual weld length len of lp is obtained by measurement. The weld overlap area during the front and rear shots is c. The minimum number of shots n required to photograph the weld can be calculated using formula 9.
[0073] Formula 9:
[0074] 13. Use Formula 10 to calculate the length for each shot. The lengths between points lp are calculated sequentially according to Formula 7, when the condition is met. The length is recorded at this point, and finally the starting point of each shot can be obtained. End point and the center point (where i represents the current weld segment being inspected, and r is shown in step eleven), k can be obtained, as shown in formula 11.
[0075] Formula 10:
[0076] Formula 11:
[0077] Fourteen, the rotation angle of the detector can then be obtained. And the detector's x-coordinate and y-coordinate, as well as the rotation angle and x-coordinate of the radiation source. y-axis As shown in formulas 12, 13, 14, 15, and 16, the xy coordinates and angles of the detector and the X-ray source relative to the center point m of each weld segment on a longitudinal weld seam are now obtained.
[0078] Formula 12:
[0079] Formula 13:
[0080] Formula 14:
[0081] Formula 15:
[0082] Formula 16:
[0083] 15. The length h of the detector's imaging area is a known condition. When inspecting the circumferential weld, the starting and ending points are obtained with point p as the center. Similarly, calculations are performed according to formulas 12, 13, 14, 15, and 16 to obtain the relative angle and xy coordinate information between the detector and the X-ray source at the current circumferential weld. Given the actual circumference C of the circumferential weld, refer to step 11 and use formula 17 to calculate the weld length t that the detector can detect each time. All points in one cycle can be calculated using formula 9.
[0084] Formula 17:
[0085] 16. Treatment of irregular welds: Extract the side view contour g1 and the top view contour g2 respectively, as described in step four. Figure 7 As shown, the two ends of the irregular weld are respectively i Point, center of the circle The point is obtained by fitting the smallest circumcircle of the outer contour g2 of the top view. The perpendicular line from o to hi intersects hi at point j and the outer contour at point k. ∠β is half the rotation angle of the weld, which also corresponds to the highest position of the weld in the side view.
[0086] 17. The length of oh pixels can be calculated using formula 18. The β angle is calculated using formula 19, and the oj pixel length is calculated using formula 20. Finally, the pixel length of jk can be obtained. As shown in Formula 21.
[0087] Formula 18:
[0088] Formula 19:
[0089] Formula 20:
[0090] Formula 21:
[0091] 18. According to By mapping the length to the side view outline, we can obtain the lp point position in a similar regular weld. When the movement reaches the highest point, we obtain the number of shots num using the same processing method as before (step thirteen). We then obtain the angle information for each rotation according to formula 22. .
[0092] Formula 22:
[0093] 19. Reference Figure 5When the bottom rotating mechanism rotates counterclockwise, moving point i to point k, the detector is at its highest position. The other half of the weld seam points are arranged in reverse order, and this process is repeated with each rotation. For the angle, referring to step 14, the relative coordinates and angle information of the detector and the X-ray source can be obtained when there is an irregular weld.
[0094] 20. The coordinates obtained from steps 14, 18, and 19 are relative coordinates in the image and need to be mapped to the physical coordinate system. The physical relative coordinates of the detector can be obtained through magnification conversion. and the physical relative coordinates of the radiation source This means that the actual detection position is relative to the coordinates, and the angle does not need to be converted, as shown in formulas 23 and 24.
[0095] Formula 23:
[0096] Formula 24:
[0097] The above-disclosed method is merely a preferred embodiment of a general method for automatically generating X-ray inspection points of end cap welds, and should not be construed as limiting the scope of this application. Those skilled in the art can understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of this application still fall within the scope of this application.
Claims
1. A universal method capable of automatically generating X-ray inspection points for head welds, characterized in that, Includes the following steps: The head is rotated 360 degrees to collect attitude data, and a proportional head outline image is drawn. The number of regular and irregular welds, weld type, actual weld length and product perimeter are input. Process regular weld types and irregular weld types, extract the outline points of the side view and top view of the regular weld type and the irregular weld type respectively, and calculate the weld length and angle of the regular weld type and the irregular weld type; Calculate the starting and ending points of the regular weld type and the irregular weld type respectively, and calculate the slope of the regular perpendicular line passing through the endpoint between the starting and ending points and the slope of the irregular perpendicular line. The rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source are calculated based on the slope of the regular vertical line and the slope of the irregular vertical line, respectively. The true physical relative coordinates of the detector and the X-ray source are restored based on the magnification of the image and the actual weld.
2. The general method for automatically generating X-ray inspection points of head welds as described in claim 1, characterized in that, The regular weld types include regular longitudinal welds and regular circumferential welds.
3. The general method for automatically generating X-ray inspection points of head welds as described in claim 1, characterized in that, The specific method for processing regular and irregular weld types, extracting the contour points of the side and top views of the regular and irregular weld types respectively, and calculating the weld length and angle of the regular and irregular weld types is as follows: For regular weld types, extract the contour points of the side and top views of the regular weld type, and calculate the weld length and angle; For irregular weld types, extract the contour points of the side and top views of the irregular weld type, and calculate the weld length and angle.
4. The general method for automatically generating X-ray inspection points of head welds as described in claim 1, characterized in that, The specific method for calculating the starting and ending points of the regular weld type and the irregular weld type, respectively, and for calculating the slopes of the regular and irregular perpendicular lines passing through the endpoints between the starting and ending points, is as follows: Calculate the start and end points of the regular weld type, and calculate the slope of the regular perpendicular line passing through the end point between the start and end points; Calculate the starting and ending points of the irregular weld type, and calculate the slope of the irregular vertical line passing through the endpoint between the starting and ending points.
5. The general method for automatically generating X-ray inspection points of head welds as described in claim 1, characterized in that, The specific method for calculating the rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source based on the slope of the regular vertical line and the slope of the irregular vertical line, respectively: The rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source are calculated based on the slope of the vertical line described above. The rotation angle, coordinate offset, and bottom rotation angle of the detector relative to the X-ray source are calculated based on the slope of the irregular vertical line.