Automatic welding control system and method for transformer oil tank production line

Abstract

The invention relates to the technical field of welding control, in particular to an automatic welding control system and method for a transformer oil tank production line, and the automatic welding method comprises the steps: obtaining a three-dimensional image of a positioning welding part, and determining the position of a welding point in a target welding area based on the three-dimensional image and a preset three-dimensional image; determining a rotation mode based on the position of the target welding area and the direction of the moving welding part, and determining a clamping position based on the rotation mode and the welding point position; the positioning welding part and the movable welding part are in butt joint, the actual groove angle and the butt joint gap of the butt joint position are detected, and the rotation angle or the movement amount of the movable welding part is determined based on the actual groove angle and the butt joint gap; and detecting the weld angle gradient of the weldment, and determining the welding angle based on the weld angle gradient. Through the key steps of determining the rotating mode and the clamping position and determining the welding angle according to the inclination of the welding seam angle, the welding precision and the welding efficiency of all parts of the welding piece are improved.

Description

Technical Field

[0001] This invention relates to the field of welding control technology, and in particular to an automatic welding control system and method for transformer tank production lines. Background Technology

[0002] The transformer oil tank serves as the mounting base for the transformer oil conservator. It is a pressure vessel constructed from welded steel plates, with the oil conservator horizontally mounted on top to regulate the oil level. The oil conservator employs a capsule-type, diaphragm-type, or corrugated structure to effectively isolate the oil from air, slowing down oil deterioration. The oil tank and oil conservator are connected by metal pipes, with gas relays installed for fault detection. Oil tank structures vary depending on capacity, ranging from bell-type to suspended-body type. Large transformers commonly utilize a fully enclosed bell-type welding process. The main body of the oil tank is a cylindrical container welded from steel plates. Medium and large transformers use a bell-type structure for fully enclosed welding, while small transformers use a suspended-body design. The oil conservator connects to the oil tank via curved connecting pipes, and its volume accounts for approximately 8% to 10% of the oil volume in the tank. Currently, due to the ongoing power grid upgrades in high-altitude areas of western China and the continued progress of the "West-to-East Power Transmission" project, the demand for transformer oil tanks in high-altitude regions is increasing.

[0003] Chinese Patent Publication No. CN103770323A discloses an automatic welding device and method for low-deformation circumferential seams in thin-walled aluminum alloy fuel tanks, used to weld the tank end plate and tank plate together in a ring. This invention simultaneously cools the weld periphery area before and after welding, increasing the cooling rate of the base material around the weld and reducing deformation before and after welding. Employing a robot-assisted control method ensures both effective cooling and accessibility of the welding position, facilitating fully automated welding of the periphery seams. When welding thin-walled aluminum alloy fuel tanks using this invention, the tack welding process can be eliminated, increasing welding efficiency by 20%–40%. This invention can achieve the welding and manufacturing of thin-walled aluminum alloy fuel tanks of different sizes, meeting the requirements for automated high-precision welding of various aluminum alloy fuel tank circumferential seams, thereby improving welding stability and enabling efficient and rapid robotic welding of thin-walled components.

[0004] It is evident that the existing technology has the following problems: In the automatic welding process, due to the lack of key steps to determine the rotation mode and clamping position within the target welding area, as well as to determine the welding angle based on the weld angle inclination, the positioning speed of each component of the welded workpiece is slow, the welding angle is prone to deviation, which in turn prolongs the welding cycle and reduces the welding accuracy. Summary of the Invention

[0005] Therefore, the present invention provides an automatic welding control system and method for transformer tank production lines to overcome the problems in the prior art where, in the automatic welding process, the key steps of determining the rotation mode and clamping position in the target welding area and determining the welding angle based on the weld angle inclination are lacking, resulting in slow positioning speed of each component of the welded workpiece, easy deviation of the welding angle, and thus extended welding cycle and reduced welding accuracy.

[0006] To achieve the above objectives, the present invention provides an automatic welding method for a transformer tank production line, comprising: A surround-layout shot is taken using several industrial cameras to obtain a three-dimensional image of the positioned welding component. The location of the welding point in the target welding area is determined based on the three-dimensional image and a preset three-dimensional image. The welding point vector is determined based on the target welding area position and the direction of the moving welding component. The rotation mode is determined based on the welding point vector, and the clamping position is determined based on the rotation mode and the position of the welding point in the target welding area. Based on the already determined rotation mode and clamping position of the positioning welding part, the positioning welding part is docked with the moving welding part to determine the welding point position. The actual bevel angle and docking gap of the docking position are detected. Based on the actual bevel angle and docking gap, the rotation angle and movement amount of the moving welding part are adjusted. Based on the welded parts after docking, the inclination of the weld seam is detected, and the welding angle is determined based on the inclination of the weld seam. The rotation method includes a full rotation method and a forward rotation method. The full rotation method is a method in which the positioning welding part rotates around a first rotation axis, and the forward rotation method is a method in which it rotates around a second rotation axis. The first rotation axis is the Z-axis perpendicular to the welding surface, and the second rotation axis is the X-axis parallel to the welding surface, and the X-axis coincides with the movement direction of the moving welding part.

[0007] Furthermore, the process of determining the location of the welding point in the target welding area based on the stereoscopic three-dimensional image and the preset three-dimensional image includes, Based on stereoscopic 3D image recognition, the actual physical coordinates of the welding points are extracted; The actual physical coordinates are compared with the standard position of the target welding area in the preset three-dimensional image to determine the specific location of the welding point within the target welding area, thus obtaining the target calibration position of the welding point within the target welding area.

[0008] Furthermore, the process of determining the welding point location vector based on the target welding area position and the direction of the moving weldment includes, The actual distance of the welding point vector is calculated based on the target calibration position and the position of the moving welding part. The actual distance is compared with the preset safe welding distance to obtain a distance comparison result. The rotation mode is determined based on the distance comparison result. The preset safe welding distance is a threshold value of the pre-set welding point position vector magnitude.

[0009] Furthermore, the process of determining the rotation mode based on the distance comparison results includes, If the actual distance is greater than the preset safe welding distance, the rotation method is determined based on the welding point vector; If the actual distance is less than or equal to the preset safe welding distance, the current relative position of the moving welding part and the welding point will be maintained.

[0010] Furthermore, the process of determining the welding point position by docking the positioning weldment with the moving weldment based on the rotation mode and clamping position determined by the positioning weldment includes, Based on the fact that the welding point position is in the same direction as the moving direction of the welding part, the welding point position is adjusted by forward rotation. The position of the welding point is adjusted by full rotation based on the direction perpendicular to the direction of movement of the moving weldment. Since the position of the welding point cannot be adjusted by rotation, the translation position of the moving welding part is adjusted to match the position of the welding point.

[0011] Furthermore, the process of determining the clamping position based on the rotation mode and the position of the welding point in the target welding area includes, Based on the location of the welding point in the target welding area, the clamping position is determined by excluding non-clamping surfaces and continuing to the location of welding points; Wherein, the non-interlocking surface is the curved welding surface of the welded part; the position of the point to be welded again is the point that needs to be welded again after the current welding point has been welded.

[0012] Furthermore, the process of detecting the actual bevel angle and gap at the docking position includes, If the bevel angle comparison result is unqualified but the butt gap comparison result is qualified, the rotation angle is adjusted to make the actual bevel angle qualified. If the bevel angle comparison result is acceptable, and the butt gap comparison result is unacceptable, the amount of movement of the moving weldment perpendicular to the welding direction is adjusted to make the butt gap acceptable. If the bevel angle comparison result is not up to standard, and the butt gap comparison result is not up to standard, the actual bevel angle is first adjusted to meet the standard by adjusting the rotation angle, and then the butt gap is adjusted to meet the standard by adjusting the movement amount. The bevel angle comparison result is a comparison between the actual bevel angle and the standard bevel angle; the butt gap comparison result is a comparison between the butt gap and the standard gap; the welding direction refers to the direction perpendicular to the butt edge.

[0013] Furthermore, the process of detecting the weld angle inclination of the welded component includes, The weld angle inclination is obtained by detecting the welding angle on a plane perpendicular to the center line of the welding angle, and the welding angle is determined based on the weld angle inclination. Wherein, the weld angle inclination is the angle between the plane containing the center line perpendicular to the welding angle and the plane containing the welding surface.

[0014] Furthermore, the process of determining the welding angle based on the weld angle inclination includes, The weld angle inclination is compared with the inclination threshold. If the weld angle inclination is less than or equal to the inclination threshold, the current welding angle is determined as the final welding angle. If the weld angle inclination is greater than the inclination threshold, a compensation angle is calculated based on the weld angle inclination. The welding angle of the welding mechanism is adjusted so that the compensated welding angle is perpendicular to the plane where the welding surface is located. The tilt threshold is set according to the sealing and strength requirements of the transformer tank welding, and the compensation angle is equal to the difference between the weld tilt angle and the tilt threshold.

[0015] The present invention also provides an automatic welding control system for a transformer tank production line, comprising, The image acquisition module is used to acquire three-dimensional images of the positioned welding parts; A welding point positioning module, which is connected to the image acquisition module, is used to compare the stereoscopic three-dimensional image with a preset three-dimensional image to determine the position of the welding point in the target welding area. The path planning module, which is connected to the welding point positioning module, is used to calculate the welding point vector based on the target welding area position and the direction of moving the welding part. An execution module, connected to the path planning module, is used to control the robotic arm to dock the positioning welding part with the moving welding part according to the determined rotation mode and gripping position. The parameter detection and adjustment module is connected to the execution module and is used to detect the actual bevel angle and docking gap at the docking position, and output rotation angle adjustment command or movement amount adjustment command to the docking execution module. The welding angle determination module is connected to the parameter detection and adjustment module to detect the weld angle inclination, calculate and output welding angle adjustment commands based on the inclination; The main control module is connected to the image acquisition module, the welding point positioning module, the path planning module, the execution module, the parameter detection and adjustment module, and the welding angle determination module, respectively, and coordinates and controls the timing and logic of the welding process.

[0016] Compared with existing technologies, the advantages of this invention lie in its ability to capture detailed features of the tank body and lid from all angles by using four industrial cameras arranged in a surround pattern and shooting simultaneously. Combined with camera intrinsic parameter correction and edge detection, irrelevant backgrounds are effectively eliminated, focusing on the crucial docking edge area and laying a precise foundation for subsequent processing. During feature point extraction and stereo matching, the uniqueness and rotation invariance of feature points, along with accurate identification of identical point pairs and removal of mismatched points, ensure reliable association of multi-view image information. Multi-view 3D coordinate calculation and point cloud fusion technology ultimately generate a complete stereo 3D model that accurately reproduces the geometry of the welded parts, providing high-precision 3D data support for welding point positioning and solving the problems of incomplete information and insufficient positioning accuracy in traditional single-view imaging. From the precise positioning of the welding point in the target welding area, to determining the welding point vector based on the target position and movement direction, and then selecting the rotation method and clamping position according to the direction, each step relies on precise 3D data to achieve a logical closed loop. The detection and adjustment of the actual bevel angle and joint gap during the welding process, along with the optimization of the welding angle based on the weld inclination, form a complete adaptive adjustment mechanism that can dynamically adapt to minor deviations or deformations in the welded parts. The flexible application of two rotation methods can specifically address position adjustment needs in different directions, ensuring precise welding and appropriate welding angles. This method achieves full automation and high precision in transformer tank welding, from image acquisition and point positioning to welding parameter adjustment. It effectively improves welding efficiency and weld quality stability, reduces errors caused by manual intervention, and meets the stringent requirements of transformer tanks for weld sealing and structural strength, providing reliable technical support for large-scale, high-quality tank production.

[0017] Furthermore, by utilizing the surround layout of a multi-camera system, the details of the mating edges between the box and the cover can be comprehensively captured. Combined with feature point extraction and edge detection technologies, key geometric features corresponding to the welding points, such as the apex of the V-groove, can be accurately identified. This provides a reliable basis for extracting the actual physical coordinates, ensuring that the coordinate data truly reflects the actual position of the welded component. By comparing the actual physical coordinates with the standard positions in the preset 3D model, the deviation between the two can be clearly quantified, clarifying the specific location of the welding point within the target welding area. This avoids the subjectivity and errors of relying on manual judgment in traditional visual positioning, making deviation assessment more objective and accurate. The deviation judgment mechanism within the allowable range strictly controls the positional accuracy of the welding point, ensuring that it is within a reasonable range of the target welding area, while retaining a certain degree of flexibility to adapt to minor deformations or installation errors of the workpiece in actual production, avoiding the problem of low adjustment efficiency caused by excessive pursuit of absolute precision. This process achieves full-process digitalization and automation of welding point positioning, from image recognition to precise localization. It provides a high-precision positional reference for subsequent welding path planning and attitude adjustment, effectively ensuring the accuracy and consistency of welding point positioning. This lays a solid foundation for improving the welding quality and production efficiency of transformer tanks. Furthermore, by clearly defining the spatial relationship between the target calibration position and the moving welding component, and using a preset safe welding distance as a benchmark, the precise determination of the welding point vector was achieved. The preset safe welding distance provides a clear boundary for adjusting the position of the moving welding component, effectively avoiding the risk of collisions caused by excessively close proximity, ensuring the safety of both the equipment and the workpiece, and building a solid safety barrier for subsequent welding operations. By calculating the difference between the actual distance and the preset safe distance, it is possible to clearly determine whether the moving welding component has reached the welding preparation state. This guides the movement direction without unnecessary operations, reducing ineffective adjustments, accelerating the pre-welding preparation pace, and improving the overall process efficiency. Using the target calibration position as a benchmark, combined with the real-time position of the moving welding component, the welding point vector is determined, ensuring a high degree of alignment between the direction and the actual docking requirements. This provides a reliable directional basis for subsequent steps such as selecting the rotation method and determining the clamping position, contributing to improved accuracy throughout the welding process. State judgment through distance comparison facilitates automated system execution, reducing the uncertainty of manual intervention and making the welding preparation stage more stable and controllable, laying a solid foundation for high-quality welding.

[0018] Furthermore, by comparing the actual distance with the preset safe welding distance, a clear adjustment logic is established to ensure that the moving welding component and the welding point are always in a safe and suitable relative position. This avoids the risk of collisions caused by excessively close distances and prevents inefficiency caused by excessively large distances. For deviations in different directions, both forward rotation and full rotation are flexibly employed to achieve precise adaptation to positional deviations. Forward rotation addresses deviations in the same direction of movement by adjusting the pitch angle to efficiently shorten the distance, ensuring positional calibration accuracy along the conveying direction. Full rotation focuses on deviations in the vertical direction, using horizontal torsion to correct offsets and ensure accurate bevel alignment. The targeted application of these two rotation methods improves the efficiency and accuracy of position adjustment. When rotation is limited, the translational position of the moving welding component is adjusted for adaptation, forming a complete adjustment loop. This avoids adjustment stagnation caused by equipment limitations and ensures that regardless of the type or magnitude of the deviation, a reasonable combination of adjustments can ensure that the actual distance meets the preset requirements. It achieves full-process adaptive adjustment from distance judgment to deviation correction, which not only ensures the safety of welding operations, but also improves the accuracy of welding point alignment, providing a reliable guarantee for the stable progress of subsequent welding processes.

[0019] Furthermore, by accurately identifying the position of the welding point within the target welding area and considering the requirements of the rotation method, the scientific elimination of non-clamping surfaces and areas where welding continues can effectively ensure the rationality and safety of the clamping position. Eliminating curved non-clamping surfaces prevents slippage during clamping, ensuring stable clamping of the weldment and reducing positional shifts caused by unstable clamping, thus providing a foundation for the accuracy of subsequent welding operations. Eliminating areas where welding continues and their surroundings provides ample space for welding operations, effectively preventing interference between the robotic arm and grippers during subsequent welding, ensuring a smooth welding process and reducing unnecessary adjustment time. Considering the specific requirements of the rotation method for the clamping position, such as symmetrical distribution on both sides of the rotation axis and maintaining a certain distance during forward rotation, the clamping position adapts to the rotation requirements, ensuring balanced force on the weldment during rotation and preventing deformation or positional deviation due to uneven force. This ensures precise alignment of the welding points after rotation, improving the quality of welding preparation. The optimized clamping position eliminates the need for readjustment when switching welding points, significantly improving the efficiency of the overall welding process, reducing time wastage caused by repetitive operations, and providing strong support for large-scale production.

[0020] Furthermore, through targeted adjustment strategies, precise control of the welding accuracy was achieved, demonstrating significant practical value. When the bevel angle is unqualified but the butt gap is qualified, correction by adjusting the rotation angle can quickly bring the bevel angle to standard without affecting the qualified gap, ensuring the welding surface fit angle meets process requirements and creating conditions for uniform molten pool formation during subsequent welding. When the bevel angle is qualified but the butt gap is unqualified, adjusting only the amount of movement perpendicular to the welding direction can precisely eliminate gap deviation while maintaining the correct angle, avoiding new deviations that might be caused by angle adjustments, ensuring the accuracy of the gap size, and facilitating control of the filler material amount and weld formation quality. For cases where both are unqualified, a step-by-step strategy of adjusting the angle first and then the gap is adopted, effectively avoiding mutual interference during the adjustment process. This ensures that the key parameter affecting welding strength, the bevel angle, is prioritized to meet the standard, while subsequent gap adjustments ensure the sealing of the weld, making the final butt joint fully meet process standards. The adjustment method, which takes into account both efficiency and precision, can flexibly respond to different types of docking deviations, significantly improve the quality and stability of transformer tank welding, and provide reliable support for ensuring the structural strength and sealing performance of the tank.

[0021] Furthermore, by accurately detecting the weld angle tilt and adjusting it accordingly, reliable support is provided for ensuring welding quality. Utilizing a laser line scanning sensor to detect within a specific plane, the degree of weld tilt deviating from the ideal state can be accurately captured. Combined with the setting of a tilt threshold, a scientific judgment is made as to whether the welding angle needs adjustment. When the tilt is within the allowable range, the current welding angle is directly adopted, simplifying the operation process while ensuring stable weld formation. When the tilt exceeds the limit, a compensation angle is calculated and the welding mechanism is adjusted to ensure that the welding torch is always perpendicular to the actual welding surface, effectively avoiding problems such as uneven weld penetration and poor weld formation caused by angle deviation. It can adapt to minor pitch deviations during weld butt joints and meets the stringent requirements of transformer tanks for weld sealing and structural strength, reducing quality risks such as leakage, improving the stability and reliability of the welding process, and providing strong protection for subsequent safe use. Attached Figure Description

[0022] Figure 1 This is a flowchart of an automated welding method for a transformer tank production line, as shown in the embodiment. Figure 2 This is a flowchart of a three-dimensional image acquisition method for an automated welding method used in a transformer tank production line, as shown in the embodiment. Figure 3 This is a flowchart illustrating the process of determining the target welding area location in the automated welding method for a transformer tank production line, as described in this embodiment. Figure 4This is a flowchart illustrating the process of determining the welding angle in the automatic welding method used in the transformer tank production line in this embodiment. Figure 5 This is a schematic diagram of the automatic welding control system used in the transformer tank production line in the embodiment. Figure 6 This is a schematic diagram of the welding device structure for the automatic welding method used in the transformer tank production line in the embodiment. Detailed Implementation

[0023] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0024] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0025] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0026] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0027] Please see Figure 1 As shown, Figure 1 This is a flowchart of an automated welding method for a transformer tank production line, as shown in the embodiment. This embodiment provides an automated welding method for a transformer tank production line, including: Step S1: Take a surround-layout shot using several industrial cameras to obtain a three-dimensional image of the positioned welding part, and determine the position of the welding point in the target welding area based on the three-dimensional image and a preset three-dimensional image. Step S2: Determine the welding point position vector based on the target welding area position and the direction of moving the welding part; Step S3: Determine the rotation mode based on the welding point vector, and determine the clamping position based on the rotation mode and the position of the welding point in the target welding area; Step S4: Based on the already determined rotation mode and clamping position of the positioning welding part, the positioning welding part is docked with the moving welding part to determine the welding point position. The actual bevel angle and docking gap of the docking position are detected. Based on the actual bevel angle and docking gap, the rotation angle and movement amount of the moving welding part are adjusted. Step S5: Based on the welded parts after docking, detect the weld angle inclination of the welded parts, and determine the welding angle based on the weld angle inclination. The rotation mode includes a full rotation mode and a forward rotation mode. The full rotation mode is a mode in which the positioning weldment rotates around a first rotation axis, and the forward rotation mode is a mode in which it rotates around a second rotation axis. The first rotation axis 1 is the Z-axis perpendicular to the welding surface, and the second rotation axis 2 is the X-axis parallel to the welding surface.

[0028] In the automated welding production line for transformer tanks, the welding components to be positioned are the tank body and the tank cover. A multi-camera system is needed to acquire three-dimensional images of both components for subsequent welding point positioning. The tank body is a rectangular cylindrical structure with dimensions of 1500mm × 1000mm × 800mm, while the tank cover is a flat structure with dimensions of 1600mm × 1100mm. Four high-resolution industrial cameras are positioned around the welding station, with the center of all camera lenses aligned with the edge of the housing to ensure complete imaging of the welding area. Among them, the front camera C1 is located 1.5m directly in front of the box, with its optical axis horizontally aligned with the center of the front of the box, to capture the front wall and edge bevel of the box; Rear camera C2: Located 1.5m directly behind the enclosure, symmetrical to C1, it captures the rear wall and edges of the enclosure; Left camera C3: Located 1.2m to the left of the enclosure, with its optical axis tilted 15° to the right, covering the edge where the left side wall of the enclosure meets the enclosure lid; Right camera C4: Located 1.2m to the right of the enclosure, symmetrical to C3, covering the edge where the right side wall of the enclosure meets the lid.

[0029] Please see Figure 2 As shown, Figure 2 This is a flowchart of an automated welding method for a transformer tank production line, as shown in the embodiment. This embodiment provides a method for acquiring a three-dimensional image of a positioning welded component. Step S1 includes: Step S11: Control 4 cameras to take pictures simultaneously, with the shooting time difference controlled within 0.1ms to avoid image misalignment caused by slight shaking of the workpiece. Each camera takes pictures of the edge contour of the welded part, the welding bevel angle of the box body, and the edge flatness of the box cover. Step S12: Correct the image based on camera intrinsic parameters, locate the outline of the welded part through edge detection algorithm, crop the background area, and retain only the docking edge between the box body and the box cover; Step S13: Extract 500-800 feature points from each of the four preprocessed images. Based on the scale and rotation invariance of the feature points, perform stereo matching between the images in the front-back direction of C1 and C2 and the left-right direction of C3 and C4 to obtain corresponding point pairs and remove mismatched points. Step S14: Based on the principle of binocular vision, using camera extrinsic parameters, the three-dimensional coordinates of matching point pairs are calculated by camera calibration according to the relative position relationship. Multi-view data are fused, and the three-dimensional point clouds calculated by C1-C2 and C3-C4 are fused to obtain a complete three-dimensional point cloud of the welded part. Step S15: Mesh the three-dimensional point cloud of the welded part to generate a three-dimensional image of the welded part. Among them, feature points are pixels in an image that are unique, stable, and repeatable, and can represent key geometric information of the object's surface; rotation invariance means that when the object is rotated, the way feature points are described will not change significantly, and they can still be accurately identified as the same feature point; corresponding point pairs can be understood as the imaging of point P1 in C1 and point P2 in C2 as the same physical point.

[0030] By employing a surround-seat layout with simultaneous shooting from four industrial cameras, the system can capture detailed features of the fuel tank body and lid from all angles. Combined with camera intrinsic parameter correction and edge detection, irrelevant background is effectively eliminated, focusing on the crucial docking edge area and laying a precise foundation for subsequent processing. During feature point extraction and stereo matching, the uniqueness and rotation invariance of feature points, along with accurate identification of identical point pairs and removal of mismatched points, ensure reliable association of multi-view image information. Multi-view 3D coordinate calculation and point cloud fusion technology ultimately generate a complete stereo model that realistically reproduces the geometry of the welded component, providing high-precision 3D data support for welding point positioning and solving the problems of incomplete information and insufficient positioning accuracy in traditional single-view imaging. From the precise positioning of the welding point in the target welding area, to determining the welding point vector based on the target position and movement direction, and then selecting the rotation method and clamping position according to the direction, each step relies on precise 3D data to achieve a logical closed loop. The detection and adjustment of the actual bevel angle and joint gap during the welding process, along with the optimization of the welding angle based on the weld inclination, form a complete adaptive adjustment mechanism that can dynamically adapt to minor deviations or deformations in the welded parts. The flexible application of two rotation methods can specifically address position adjustment needs in different directions, ensuring precise welding and appropriate welding angles. This method achieves full automation and high precision in transformer tank welding, from image acquisition and point positioning to welding parameter adjustment. It effectively improves welding efficiency and weld quality stability, reduces errors caused by manual intervention, and meets the stringent requirements of transformer tanks for weld sealing and structural strength, providing reliable technical support for large-scale, high-quality tank production.

[0031] Specifically, in step S1, the process of determining the location of the welding point in the target welding area based on the stereoscopic three-dimensional image and the preset three-dimensional image includes, Based on stereoscopic 3D image recognition, the actual physical coordinates of the welding points are extracted; The actual physical coordinates are compared with the standard position of the target welding area in the preset three-dimensional image to determine the specific location of the welding point within the target welding area, thus obtaining the target calibration position of the welding point within the target welding area.

[0032] A multi-camera system with four industrial cameras arranged in a surround layout is used to obtain a three-dimensional model of the box and the lid. The three-dimensional coordinate system takes the center of the production line workbench as the origin, the X-axis is the horizontal left and right direction with positive to the right, the Y-axis is the horizontal front and back direction along the production line conveying direction with positive forward, and the Z-axis is the vertical direction with positive upward. Please see Figure 3 As shown, Figure 3 This is a flowchart illustrating the process of determining the target welding area location in the automated welding method for a transformer tank production line, as described in this embodiment. In this embodiment, the corner weld between the vertical wall and the horizontal cover of the transformer tank is taken as an example. The target welding area is the edge of the 90° angle formed by the two, with a length of 2000mm. The preset welding points are 20 weld points numbered W1 to W20, evenly distributed along this edge, with a designed spacing of 100mm. The following is the process of determining the position of welding point W10 in the target welding area, including... Step S21: Extract image feature points, combine edge detection to locate the mating edge between the box body and the box cover, identify the V-shaped bevel vertex corresponding to welding point W10, characterized by the intersection of the two bevel edges, analyze the 3D point cloud data, and obtain the actual physical coordinates of welding point W10 as P1. W10 = (998.7, 1002.3, 501.1); Step S22: The preset 3D image is the 3D model of the fuel tank in the design phase, where the standard position of welding point W10 is P2. W10 = (X=1000, Y=1000, Z=500), where the point on the X-axis is 1000mm to the right of the geometric center origin of the worktable at the welding point, and is perpendicular to the conveying direction of the moving welding part cover, corresponding to the left-right position of the front edge of the tank body and matching the width of the tank body; the point on the Y-axis is 1000mm in front of the geometric center origin of the worktable along the production line conveying direction, corresponding to the front-back position of the front edge of the tank body and matching the length of the tank body, and is aligned with the feed path of the moving welding part; the point on the Z-axis is 500mm above the worktable, corresponding to the height of the vertical wall of the tank body and matching the height of the tank body, and is the apex height of the bevel between the tank body and the cover; The standard position is determined based on the structural characteristics and welding process requirements of the transformer tank. The tank body is a rectangular cylindrical structure measuring 1500mm × 1000mm × 800mm, and the tank cover is a flat plate structure measuring 1600mm × 1100mm. (P2) W10 The dimensions X=1000mm, Y=1000mm, and Z=500mm are all within the size range of the tank body and the tank cover, and correspond to the intersection of the vertical wall of the tank body and the edge of the tank cover at the corner weld joint where the two meet. The standard position is the key point of the 3D model of the fuel tank in the preset 3D image design stage. In the subsequent actual welding, the coordinates of the actual welding point of the positioning welding part of the tank body need to be compared with P2. W10 Compare with actual coordinates P1 W10 = (998.7, 1002.3, 501.1) and P2 W10 The deviation is calculated to determine whether adjustments are needed, ensuring that the welding point is within the target welding area; Step S23: Calculate the deviation between the actual physical coordinates and the standard position: △X = 998.7 - 1000 = -1.3 mm, 1.3 mm to the left along the X-axis; △Y = 1002.3 - 1000 = 2.3 mm, 2.3 mm forward along the Y-axis; △Z = 501.1 - 500 = 1.1 mm, 1.1 mm upward along the Z-axis. Step S24: If the deviation is within the allowable range, the welding point is in a reasonable position within the target welding area and no adjustment is required. The allowable range is ±3mm.

[0033] By utilizing a multi-camera system's surround layout, the system can comprehensively capture the details of the mating edges between the casing and the cover. Combined with feature point extraction and edge detection technologies, it can accurately identify key geometric features corresponding to the welding points, such as the apex of the V-groove. This provides a reliable basis for extracting the actual physical coordinates, ensuring that the coordinate data truly reflects the actual position of the welded component. By comparing the actual physical coordinates with the standard positions in the preset 3D model, the deviation between the two can be clearly quantified, clarifying the specific location of the welding point within the target welding area. This avoids the subjectivity and errors of traditional visual positioning that rely on manual judgment, making deviation assessment more objective and accurate. The allowable deviation judgment mechanism strictly controls the positional accuracy of the welding point, ensuring it is within a reasonable range of the target welding area, while retaining a certain degree of flexibility to adapt to minor deformations or installation errors of the workpiece in actual production, avoiding the problem of low adjustment efficiency caused by excessive pursuit of absolute precision. This process achieves full-process digitalization and automation of welding point positioning, from image recognition to precise positioning. It provides a high-precision position reference for subsequent welding path planning, posture adjustment, and other steps, effectively ensuring the accuracy and consistency of welding point positioning, and laying a solid foundation for improving the welding quality and production efficiency of transformer tanks.

[0034] Specifically, in step S2, the process of determining the welding point position vector based on the target welding area position and the direction of moving the weldment includes, The actual distance of the welding point vector is calculated based on the target calibration position and the position of the moving welding part. The actual distance is compared with the preset safe welding distance to obtain a distance comparison result. The rotation mode is determined based on the distance comparison result. The preset safe welding distance is a threshold value of the pre-set welding point position vector magnitude.

[0035] The moving welding component is the box cover to be docked. It is conveyed forward along the Y-axis of the production line. Its current position, identified by the multi-camera system, is K = (998.7, 1050.0, 501.1). It forms a 90° angle with the box body along the positive Y-axis. The target calibration position is the precise coordinates of welding point W10, which serves as the welding reference point. Moving the welding component (box cover) changes the actual distance between the current position and the target calibration position. The preset safe welding distance is determined according to welding process requirements; in this embodiment, it is set to 30mm. This refers to the shortest distance between the welding point and the moving welding component that allows the welding operation to begin. A distance less than this may cause a collision; a distance greater than this requires position adjustment. Based on the coordinates of two points in the three-dimensional coordinate system, the actual distance between the current position of the box cover and the calibration position of target W10 is calculated to be 47.7 mm. The calculation process is based on existing technology and will not be elaborated here. Since 47.7mm is greater than 30mm, it means that the moving welding part cover has not yet reached the welding preparation position. It needs to continue moving along the positive Y-axis until the actual distance is ≤30mm. When the cover moves to the actual distance equal to the preset safe welding distance, its position is K1=(998.7, 1032.3, 501.1). At this time, the welding point vector is the direction from the W10 target calibration position to the edge of the cover.

[0036] By clearly defining the spatial relationship between the target calibration position and the moving welding component, and using a preset safe welding distance as a benchmark, the precise determination of the welding point vector is achieved. The preset safe welding distance provides a clear boundary for adjusting the position of the moving welding component, effectively avoiding the risk of collisions caused by excessively close proximity, ensuring the safety of both the equipment and the workpiece, and building a solid safety barrier for subsequent welding operations. By calculating the difference between the actual distance and the preset safe distance, it is possible to clearly determine whether the moving welding component has reached the welding preparation state. This guides the movement direction without unnecessary operations, reducing ineffective adjustments, accelerating the pre-welding preparation pace, and improving the overall process efficiency. Using the target calibration position as a benchmark, combined with the real-time position of the moving welding component, the welding point vector is determined, ensuring a high degree of alignment between the direction and the actual docking requirements. This provides a reliable directional basis for subsequent steps such as selecting the rotation method and determining the clamping position, contributing to improved accuracy throughout the welding process. Status judgment through distance comparison facilitates automated system execution, reducing the uncertainty of manual intervention and making the welding preparation stage more stable and controllable, laying a solid foundation for high-quality welding.

[0037] Specifically, the process of determining the rotation mode based on the distance comparison results includes, If the actual distance is greater than the preset safe welding distance, the rotation method is determined based on the welding point vector; If the actual distance is less than or equal to the preset safe welding distance, the current relative position of the moving welding part and the welding point will be maintained.

[0038] Specifically, the process of determining the welding point location by aligning the positioning welding part with the moving welding part based on the rotation mode and clamping position determined by the positioning welding part includes, Based on the fact that the welding point position is in the same direction as the moving direction of the welding part, the welding point position is adjusted by forward rotation. The position of the welding point is adjusted by full rotation based on the direction perpendicular to the direction of movement of the moving weldment. Since the position of the welding point cannot be adjusted by rotation, the translation position of the moving welding part is adjusted to match the position of the welding point.

[0039] Forward rotation mode: Rotate around the X-axis to adjust the pitch angle of the cover and adapt to positional deviations along the Y-axis. Full rotation mode: Rotate around the Z-axis to adjust the horizontal torsion angle of the cover, accommodating deviations perpendicular to the Y-axis. The welding point is in the same direction as the movement, but deviates in the Y-axis direction. The cover is ahead along the Y-axis, with an actual distance of 47.7mm. However, the X and Z axis coordinates are consistent with the target calibration position. The relative position of the welding point and the moving welding part cover is in the same direction as the Y-axis. Using a forward rotation method, the cover is tilted forward by 3° around the X-axis, and the edge of the cover is slightly adjusted in the negative Y-axis direction, shortening the actual distance to 35mm. The cover is then moved 5mm along the positive Y-axis direction, and the final actual distance is 30mm, which meets the preset safe welding distance requirement. The welding point is located perpendicular to the direction of movement, with a deviation in the X-axis direction. The current position of the cover (1010.0, 1030.0, 501.1) has an actual distance of 29.8mm, approximately equal to 30mm. However, the X-axis deviation is 11.3mm, perpendicular to the direction of movement, causing the bevel alignment to shift. There is a vertical X-axis deviation between the welding point and the relative position of the moving welding part. A full rotation method is adopted, rotating around the Z-axis. The cover is controlled to rotate 2° clockwise around the Z-axis. This full rotation angle corrects the X-axis deviation from 11.3mm to 0.5mm, which is within the allowable range. At this time, the actual distance is still maintained at 30mm. No adjustment of the movement is required, and the docking process can proceed directly. The rotation method could not be adjusted. The cover position was (1020.0, 1080.0, 510.0), with an X-axis deviation of 21.3mm and a Z-axis deviation of 8.9mm. The actual distance was 81mm, and the rotation angle exceeded the limit. The maximum rotation angle of the equipment (±5°) could not be corrected. The translation position of the moving welded part was adjusted. The cover was moved 20mm in the negative X-axis direction and 8mm in the negative Z-axis direction. After translation, the position was (1000.0, 1080.0, 502.0). The actual distance after translation was calculated to be 77.72mm. Further adjustment was made by rotating the cover 2° around the X-axis using the forward rotation method. Due to the rotation, the edge of the cover moved about 3.49mm closer to the negative Y-axis direction. At this time, the actual distance was about 77.72-3.49=74.23mm. Finally, the cover was moved 44.23mm in the negative Y-axis direction. The cover position was finally reached, with an actual distance of 30mm, which met the requirements.

[0040] By comparing the actual distance with the preset safe welding distance, a clear adjustment logic is established to ensure that the moving welding component and the welding point are always in a safe and suitable relative position. This avoids the risk of collisions caused by excessively close distances and prevents inefficiency caused by excessively large distances. For deviations in different directions, two methods, forward rotation and full rotation, are flexibly employed to achieve precise adaptation to positional deviations. Forward rotation addresses deviations in the same direction of movement by adjusting the pitch angle to efficiently shorten the distance and ensure positional calibration accuracy along the conveying direction. Full rotation focuses on deviations in the vertical direction, using horizontal torsion to correct offsets and ensure accurate bevel alignment. The targeted application of these two rotation methods improves the efficiency and accuracy of position adjustment. When rotation is limited, the translational position of the moving welding component is adjusted to adapt, forming a complete adjustment loop. This avoids adjustment stagnation caused by equipment limitations and ensures that regardless of the type or magnitude of the deviation, a reasonable combination of adjustments can ensure that the actual distance meets the preset requirements. It achieves full-process adaptive adjustment from distance judgment to deviation correction, which not only ensures the safety of welding operations, but also improves the accuracy of welding point alignment, providing a reliable guarantee for the stable progress of subsequent welding processes.

[0041] Specifically, the process of determining the clamping position based on the rotation mode and the position of the welding point in the target welding area includes, Based on the location of the welding point in the target welding area, the clamping position is determined by excluding non-clamping surfaces and continuing to the location of welding points; Wherein, the non-interlocking surface is the curved welding surface of the welded part; the position of the point to be welded again is the point that needs to be welded again after the current welding point has been welded.

[0042] The lid is not a sandwich surface. There are two arc-shaped protrusions with a curvature radius of 50mm in the middle of the lid, which are non-clipped surfaces with curvature. The 20mm wide edge bevel area is excluded from the clamping range because welding is required. The clamping position around the X-axis should avoid the area near the rotation axis and ensure that the lid is balanced when rotating. The current welding point W10 is located at the midpoint of the front edge of the box cover. The next welding points W11 are 100mm to the right of W10, W12 is 100mm to the right of W11, and W13 is 100mm to the right of W12, distributed sequentially along the front edge. The target welding area is the 20mm wide bevel area on the front edge of the box cover. The clamping position must be at least 50mm away from this area to avoid obstructing the welding path. Identify the non-clamped surface of the lid. The coordinate range of the central arc-shaped protrusion area is 500-700mm in the X direction and 400-600mm in the Y direction. Due to its curvature, it is easy to slip when clamping, so it should be directly excluded. The bevel edge area where all welding points are located is 20mm wide. Exclude it from clamping to avoid damaging the bevel or affecting the welding.

[0043] The welding points W11-W13 are located to the right of W10. A 50mm radius around them, within the range X: 1098.7-1398.7mm and Y: 1002.3-1052.3mm, needs to be reserved for welding operations to prevent the robotic arm from interfering with the grippers during subsequent welding. The clamping positions for the front rotating mechanism around the X-axis must be symmetrically distributed on both sides of the rotation axis. The X-axis runs along the length of the cover, with a Y=550mm radius, and the distance from the rotation axis must be greater than or equal to 300mm to ensure stable rotational torque. The remaining selectable areas include flat, non-curved surfaces and locations far from the points to be welded and those to be welded further. Select two symmetrical grip points: The clamping point A = (300, 300, 501.1) is located in the middle of the left side of the box cover, flat and without curvature, and is ≥300mm away from W10 and the point to be welded. The clamping point B = (1300, 300, 501.1) is located in the middle of the right side of the box cover, and is symmetrical to point A about the X-axis, satisfying the force balance requirement of the forward rotation.

[0044] Both gripping points A and B avoid non-gripping surfaces and areas to be welded, and are 80mm away from the target welding area, without affecting the welding path. When gripping the box cover at these two positions and rotating it 2° around the X-axis, there is no slippage or interference. After rotation, point W10 is precisely aligned with the box bevel, meeting the welding preparation requirements. When welding W11-W13 subsequently, the grippers do not need to be readjusted, as operating space has been reserved, and the welding point can be switched directly, improving process efficiency.

[0045] By accurately identifying the welding point's location within the target welding area and considering the rotation requirements, non-clamping surfaces and areas awaiting further welding are scientifically excluded, effectively ensuring the rationality and safety of the clamping position. Excluding curved non-clamping surfaces prevents slippage during clamping, ensuring stable holding of the weldment and reducing positional shifts caused by unstable clamping, thus providing a foundation for the accuracy of subsequent welding operations. Excluding areas awaiting further welding and their surroundings provides ample space for welding operations, effectively preventing interference between the robotic arm and grippers during subsequent welding, ensuring a smooth welding process and reducing unnecessary adjustment time. Considering the specific requirements of the rotation method for the clamping position, such as symmetrical distribution on both sides of the rotation axis with a certain distance during forward rotation, the clamping position adapts to the rotation requirements, ensuring balanced force on the weldment during rotation and preventing deformation or positional deviation due to uneven force. This guarantees precise alignment of the welding points after rotation, improving the quality of welding preparation. The optimized clamping position eliminates the need for readjustment when switching welding points, significantly improving the efficiency of the overall welding process, reducing time wastage caused by repetitive operations, and providing strong support for large-scale production.

[0046] Specifically, the process of detecting the actual bevel angle and gap at the docking position includes, If the bevel angle comparison result is unqualified but the butt gap comparison result is qualified, the rotation angle is adjusted to make the actual bevel angle qualified. If the bevel angle comparison result is acceptable, and the butt gap comparison result is unacceptable, the amount of movement of the moving weldment perpendicular to the welding direction is adjusted to make the butt gap acceptable. If the bevel angle comparison result is not up to standard, and the butt gap comparison result is not up to standard, the actual bevel angle is first adjusted to meet the standard by adjusting the rotation angle, and then the butt gap is adjusted to meet the standard by adjusting the movement amount. The bevel angle comparison result is a comparison between the actual bevel angle and the standard bevel angle; the butt gap comparison result is a comparison between the butt gap and the standard gap; the welding direction refers to the direction perpendicular to the butt edge.

[0047] A laser profile sensor is used to detect the actual bevel angle and butt joint gap. The rotation angle is adjusted by rotating the cover around the Z-axis, and the movement is achieved by translating the cover along the Y-axis perpendicular to the welding direction. Since the welding direction is the negative X-axis, the perpendicular direction is achieved by translation along the Y-axis. In this embodiment, the standard bevel angle is set to 60°, and the standard gap is 2mm. The bevel angle is not up to standard, but the butt joint gap is up to standard. The actual bevel angle is 55°, and the butt joint gap is 2.0mm. Cause of deviation: The cover rotated 2.5° counterclockwise around the Z-axis, resulting in a smaller fitting angle between the bevels on both sides. Adjustment steps: Rotate the control box cover clockwise by 2.5° around the Z-axis to fully rotate the angle, so that the bevels on both sides reopen to 60°; Re-inspection: The actual bevel angle is 60°, and the mating gap is still 2.0mm. Because the rotating shaft passes through the bevel apex, the gap is not affected.

[0048] The bevel angle is acceptable, but the butt joint gap is not. Test results: Actual bevel angle 60°, butt joint gap 3.5mm; Cause of deviation: The cover deviates from the box body by 0.75mm along the positive Y-axis. This translational deviation perpendicular to the welding direction leads to an increase in the gap. Adjustment steps: Calculate the movement amount. According to the geometric relationship, for every 1mm increase in the butt gap, it needs to move 0.5mm along the negative Y-axis, perpendicular to the welding direction. Therefore, the required movement amount is (3.5-2.0)×0.5=0.75mm. The control box cover is moved 0.75mm along the negative Y-axis. Re-inspection: The gap between the joints is 2.0mm, the bevel angle is still 60°, and translation does not affect the angle.

[0049] Both the bevel angle and the joint gap are substandard. Test results: Actual bevel angle 53°, butt joint gap 1.0mm. Cause of deviation: The cover rotated 3.5° counterclockwise around the Z-axis, resulting in a smaller angle. Simultaneously, it shifted 0.5mm in the negative Y-axis direction, causing the clearance to be too small. Adjustment steps: Step 1: Adjust the angle: Rotate the control box cover 3.5° clockwise around the Z-axis to restore the actual bevel angle to 60°. At this point, the rotation will cause the box cover to shift slightly, reducing the mating gap to 1.2mm. The second step is to adjust the clearance: calculate the required movement along the positive Y-axis as (2.0-1.2)×0.5=0.4mm. The control box cover was moved 0.4mm along the positive Y-axis, and the mating gap was checked again to be 2.0mm, with a bevel angle of 60°.

[0050] Through targeted adjustment strategies, precise control of the welding accuracy of welded parts was achieved, demonstrating significant practical value. When the bevel angle is unqualified but the butt gap is qualified, correction by adjusting the rotation angle can quickly bring the bevel angle to standard without affecting the qualified gap, ensuring the welding surface fit angle meets process requirements and creating conditions for uniform molten pool formation during subsequent welding. When the bevel angle is qualified but the butt gap is unqualified, adjusting only the amount of movement perpendicular to the welding direction can precisely eliminate gap deviation while maintaining the correct angle, avoiding new deviations that may be caused by angle adjustments, ensuring the accuracy of the gap size, and facilitating control of the filler material amount and weld formation quality. For cases where both are unqualified, a step-by-step strategy of adjusting the angle first and then the gap is adopted, effectively avoiding mutual interference during the adjustment process. This ensures that the key parameter affecting weld strength, the bevel angle, is prioritized to meet the standard, while subsequent gap adjustments ensure the weld's sealing, resulting in a final butt joint that fully meets process standards. The adjustment method, which takes into account both efficiency and precision, can flexibly respond to different types of docking deviations, significantly improve the quality and stability of transformer tank welding, and provide reliable support for ensuring the structural strength and sealing performance of the tank.

[0051] Specifically, the process of detecting the weld angle inclination of the welded component includes, The weld angle inclination is obtained by detecting the welding angle on a plane perpendicular to the center line of the welding angle, and the welding angle is determined based on the weld angle inclination. Wherein, the weld angle inclination is the angle between the plane containing the center line perpendicular to the welding angle and the plane containing the welding surface.

[0052] Please see Figure 4 As shown, Figure 4 This is a flowchart illustrating the process of determining the welding angle in the automatic welding method used in the transformer tank production line in this embodiment. Specifically, the process of determining the welding angle based on the weld angle inclination includes, The weld angle inclination is compared with the inclination threshold. If the weld angle inclination is less than or equal to the inclination threshold, the current welding angle is determined as the final welding angle. If the weld angle inclination is greater than the inclination threshold, a compensation angle is calculated based on the weld angle inclination. The welding angle of the welding mechanism is adjusted so that the compensated welding angle is perpendicular to the plane where the welding surface is located. The tilt threshold is set according to the sealing and strength requirements of the transformer tank welding, and the compensation angle is equal to the difference between the weld tilt angle and the tilt threshold.

[0053] In this embodiment, the tilt threshold is set to 3°, which is set according to the fuel tank sealing requirements. The laser line scanning sensor detects a plane perpendicular to the welding angle centerline, i.e., along the YZ plane. Due to the angular deviation of the welding angle centerline along the X-axis, the welding torch can rotate around the X-axis to adjust the pitch angle, compensating for the weld angle inclination and ensuring that the welding torch axis is perpendicular to the welding surface. The centerline of the welding angle is along the X-axis, consistent with the welding direction, and is the theoretical axis of symmetry of the weld. The plane perpendicular to the centerline is the YZ plane, a vertical plane used to detect the vertical inclination of the weld. The plane containing the welding surface is the plane forming a 90° angle between the XZ plane of the front wall of the enclosure and the XY plane of the top surface of the enclosure. Ideally, the weld should be distributed along the angle bisector of this plane. The weld angle inclination is the angle between the actual weld in the YZ plane and the plane containing the welding surface, that is, the angle by which the weld deviates from the ideal angle bisector. A laser line scanning sensor emits a laser beam to scan the weld area along the YZ plane, acquiring weld cross-sectional contour data. Image processing is used to extract the projection of the actual weld centerline onto the YZ plane, which is then compared with the ideal angle bisector of the plane containing the weld surface to calculate the angle difference. For example: If the scan reveals that the actual weld centerline is inclined upwards in the YZ plane, forming a 2.5° angle with the ideal angle bisector, then the weld angle inclination is 2.5°. The weld angle inclination is less than 3° and within the allowable range. The current welding angle does not need to be adjusted, which can ensure the weld formation quality. The current welding angle is preset to 45°, which is perpendicular to the ideal welding surface, and is determined as the final welding angle. The welding torch is applied at a 45° angle. The weld metal fills the V-shaped groove evenly, and the weld is flat and meets the sealing requirements. The weld angle inclination is 4.2°, which is greater than 3°. The inclination direction is upward in the YZ plane. There is a slight pitch deviation when the box cover is joined, resulting in a 4.2° inclination between the actual plane and the ideal plane of the weld surface. Compensation angle = Weld angle inclination - Inclination threshold = 4.2° - 3° = 1.2° Adjust the welding mechanism: Control the welding torch to rotate upward by 1.2° around the X-axis, consistent with the tilt direction, so that the compensated welding angle is 45° + 1.2° = 46.2°. After compensation, the welding torch axis is perpendicular to the plane where the actual welding surface is located by 46.2°, which just cancels the 4.2° tilt.

[0054] By accurately detecting the weld angle and tilt and adjusting it accordingly, reliable support is provided for ensuring welding quality. Utilizing a laser line scanning sensor to detect within a specific plane, the degree of weld tilt deviating from the ideal state can be accurately captured. Combined with the setting of a tilt threshold, a scientific judgment is made as to whether the welding angle needs adjustment. When the tilt is within the allowable range, the current welding angle is directly adopted, simplifying the operation process while ensuring stable weld formation. When the tilt exceeds the limit, a compensation angle is calculated and the welding mechanism is adjusted to ensure that the welding torch is always perpendicular to the actual welding surface, effectively avoiding problems such as uneven weld penetration and poor weld formation caused by angle deviation. It can adapt to minor pitch deviations during weld butt joints and meets the stringent requirements of transformer tanks for weld sealing and structural strength, reducing quality risks such as leakage, improving the stability and reliability of the welding process, and providing strong protection for subsequent safe use.

[0055] This embodiment also provides an automatic welding control system for a transformer tank production line, including, The image acquisition module is used to acquire three-dimensional images of the positioned welding parts; A welding point positioning module, which is connected to the image acquisition module, is used to compare the stereoscopic three-dimensional image with a preset three-dimensional image to determine the position of the welding point in the target welding area. The path planning module, which is connected to the welding point positioning module, is used to calculate the welding point vector based on the target welding area position and the direction of moving the welding part. An execution module, connected to the path planning module, is used to control the robotic arm to dock the positioning welding part with the moving welding part according to the determined rotation mode and gripping position. The parameter detection and adjustment module is connected to the execution module and is used to detect the actual bevel angle and docking gap at the docking position, and output rotation angle adjustment command or movement amount adjustment command to the docking execution module. The welding angle determination module is connected to the parameter detection and adjustment module to detect the weld angle inclination, calculate and output welding angle adjustment commands based on the inclination; The main control module is connected to the image acquisition module, the welding point positioning module, the path planning module, the execution module, the parameter detection and adjustment module, and the welding angle determination module, respectively, and coordinates and controls the timing and logic of the welding process.

[0056] Please see Figure 6 , Figure 6 This is a schematic diagram of the welding device structure for the automatic welding method used in the transformer tank production line in the embodiment; The first rotation axis 1 is used to rotate along the Z-axis perpendicular to the welding surface; The second rotating shaft 2 is used to rotate along the Y-axis parallel to the welding surface; Welding head 3 is used for positioning and moving the welding parts.

[0057] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An automated welding method for a transformer tank production line, characterized in that, include: A surround-layout shot is taken using several industrial cameras to obtain a three-dimensional image of the positioned welding component. The location of the welding point in the target welding area is determined based on the three-dimensional image and a preset three-dimensional image. The welding point vector is determined based on the target welding area position and the direction of the moving welding component. The rotation mode is determined based on the welding point vector, and the clamping position is determined based on the rotation mode and the position of the welding point in the target welding area. Based on the already determined rotation mode and clamping position of the positioning welding part, the positioning welding part is docked with the moving welding part to determine the welding point position. The actual bevel angle and docking gap of the docking position are detected. Based on the actual bevel angle and docking gap, the rotation angle and movement amount of the moving welding part are adjusted. Based on the welded parts after docking, the inclination of the weld seam is detected, and the welding angle is determined based on the inclination of the weld seam. The rotation method includes a full rotation method and a forward rotation method. The full rotation method is a method in which the positioning welding part rotates around a first rotation axis, and the forward rotation method is a method in which it rotates around a second rotation axis. The first rotation axis is the Z-axis perpendicular to the welding surface, and the second rotation axis is the X-axis parallel to the welding surface, and the X-axis coincides with the movement direction of the moving welding part.

2. The automatic welding method for transformer tank production line according to claim 1, characterized in that, The process of determining the location of the welding point in the target welding area based on the stereoscopic three-dimensional image and the preset three-dimensional image includes, Based on stereoscopic 3D image recognition, the actual physical coordinates of the welding points are extracted; The actual physical coordinates are compared with the standard position of the target welding area in the preset three-dimensional image to determine the specific location of the welding point within the target welding area, thus obtaining the target calibration position of the welding point within the target welding area.

3. The automatic welding method for transformer tank production line according to claim 2, characterized in that, The process of determining the welding point location vector based on the target welding area location and the direction of the moving weldment includes, The actual distance of the welding point vector is calculated based on the target calibration position and the position of the moving welding part. The actual distance is compared with the preset safe welding distance to obtain a distance comparison result. The rotation mode is determined based on the distance comparison result. The preset safe welding distance is a threshold value of the pre-set welding point position vector magnitude.

4. The automatic welding method for transformer tank production line according to claim 3, characterized in that, The process of determining the rotation mode based on the distance comparison results includes: If the actual distance is greater than the preset safe welding distance, the rotation method is determined based on the welding point vector; If the actual distance is less than or equal to the preset safe welding distance, the current relative position of the moving welding part and the welding point will be maintained.

5. The automatic welding method for transformer tank production line according to claim 4, characterized in that, The process of determining the welding point position by aligning the positioning welding part with the moving welding part based on the rotation mode and clamping position determined by the positioning welding part includes, Based on the fact that the welding point position is in the same direction as the moving direction of the welding part, the welding point position is adjusted by forward rotation. The position of the welding point is adjusted by full rotation based on the direction perpendicular to the direction of movement of the moving weldment. Since the position of the welding point cannot be adjusted by rotation, the translation position of the moving welding part is adjusted to match the position of the welding point.

6. The automatic welding method for transformer tank production line according to claim 5, characterized in that, The process of determining the clamping position based on the rotation method and the position of the welding point in the target welding area includes, Based on the location of the welding point in the target welding area, the clamping position is determined by excluding non-clamping surfaces and continuing to the location of welding points; Wherein, the non-interlocking surface is the curved welding surface of the welded part; the position of the point to be welded again is the point that needs to be welded again after the current welding point has been welded.

7. The automatic welding method for transformer tank production line according to claim 6, characterized in that, The process of detecting the actual bevel angle and gap at the docking position includes, Based on the fact that the bevel angle comparison result is unqualified while the butt joint gap comparison result is qualified, the rotation angle is adjusted to make the actual bevel angle qualified. If the bevel angle comparison result is acceptable, and the butt gap comparison result is unacceptable, the amount of movement of the moving weldment perpendicular to the welding direction is adjusted to make the butt gap acceptable. If the bevel angle comparison result is not up to standard, and the butt gap comparison result is not up to standard, the actual bevel angle is first adjusted to meet the standard by adjusting the rotation angle, and then the butt gap is adjusted to meet the standard by adjusting the movement amount. The bevel angle comparison result is a comparison between the actual bevel angle and the standard bevel angle; the butt gap comparison result is a comparison between the butt gap and the standard gap; the welding direction refers to the direction perpendicular to the butt edge.

8. The automatic welding method for transformer tank production line according to claim 7, characterized in that, The process of detecting the weld angle inclination of the welded component includes, The weld angle inclination is obtained by detecting the welding angle on a plane perpendicular to the center line of the welding angle, and the welding angle is determined based on the weld angle inclination. Wherein, the weld angle inclination is the angle between the plane containing the center line perpendicular to the welding angle and the plane containing the welding surface.

9. The automatic welding method for a transformer tank production line according to claim 8, characterized in that, The process of determining the welding angle based on the weld inclination includes: The weld angle inclination is compared with the inclination threshold. If the weld angle inclination is less than or equal to the inclination threshold, the current welding angle is determined as the final welding angle. If the weld angle inclination is greater than the inclination threshold, a compensation angle is calculated based on the weld angle inclination. The welding angle of the welding mechanism is adjusted so that the compensated welding angle is perpendicular to the plane where the welding surface is located. The tilt threshold is set according to the sealing and strength requirements of the transformer tank welding, and the compensation angle is equal to the difference between the weld tilt angle and the tilt threshold.

10. An automatic welding control system for a transformer tank production line, which applies the automatic welding method for a transformer tank production line according to any one of claims 1-9, characterized in that, include, The image acquisition module is used to acquire three-dimensional images of the positioned welding parts; A welding point positioning module, which is connected to the image acquisition module, is used to compare the stereoscopic three-dimensional image with a preset three-dimensional image to determine the position of the welding point in the target welding area. The path planning module, which is connected to the welding point positioning module, is used to calculate the welding point vector based on the target welding area position and the direction of moving the welding part. An execution module, connected to the path planning module, is used to control the robotic arm to dock the positioning welding part with the moving welding part according to the determined rotation mode and gripping position. The parameter detection and adjustment module is connected to the execution module and is used to detect the actual bevel angle and docking gap at the docking position, and output rotation angle adjustment command or movement amount adjustment command to the docking execution module. The welding angle determination module is connected to the parameter detection and adjustment module to detect the weld angle inclination, calculate and output welding angle adjustment commands based on the inclination; The main control module is connected to the image acquisition module, the welding point positioning module, the path planning module, the execution module, the parameter detection and adjustment module, and the welding angle determination module, respectively, and coordinates and controls the timing and logic of the welding process.

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