Laser welding method for non-magnetic metal material

Abstract

A laser welding method for a non-magnetic metal material comprises the following steps that a welding target object is a plate made of a non-magnetic metal plate material, and the length of the welding target object is larger than or equal to 9 m; forming a welding seam on the spliced side edges of the first plate and the second plate, performing image acquisition on the welding seam, and converting to obtain an original line contour of the welding seam; a laser welder emits laser to start scanning and welding from one end of a welding seam; a welding seam image obtained after scanning welding is obtained in real time, and filtering processing is conducted on the welding seam image to obtain a two-dimensional image; analyzing line contours in the two-dimensional image, finding out lines conforming to features through edge detection and contour extraction, recognizing the position of a welding seam, and adjusting the position of a laser welder according to absolute coordinates of the welding seam when the actual position of the welding seam is changed, so that the error between the welding seam position obtained in real time and the absolute coordinates is within a set range. And dynamic accurate tracking is realized. Welding of long-weld-joint plates can be completed at a time, and the welding quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of laser welding, in particular to a laser welding method for non-magnetic metal materials. Background Art

[0002] At present, the welding of non-magnetic metal materials in the market can only stay in the traditional arc welding, deep fusion welding and other welding methods. There are generally problems such as large welding width, uneven welding depth, unsightly back molding, etc. The welding of the front and back is inconsistent and needs to be turned over. The welding speed is generally within 500mm per minute, and it is impossible to stably weld a weld longer than 9 meters at a time. The qualified rate after welding is not high, and the defects caused by instability need to be manually supplemented. The amount of filler wire is particularly large, the cost is high, and the efficiency is low. With the current structure, when welding a long weld, the welding head generates a lot of heat for a long time, which is difficult to dissipate in time and easily damages the lens. There is also a lack of effective positioning for the plate. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a laser welding device and method for non-magnetic metal materials.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] A laser welding method for non-magnetic metal materials comprises the following steps:

[0006] The welding target object is a plate made of non-magnetic metal plate material with a length greater than or equal to 9 meters;

[0007] On the work surface, the sides of the first plate and the second plate that need to be welded are spliced ​​together, the first plate and the second plate are pressed together to keep them stable, a weld is formed at the sides where the first plate and the second plate are spliced ​​together, an image of the weld is acquired, and the original line profile of the weld is obtained by conversion;

[0008] The laser welder is started, and the laser welder emits a laser to start scanning welding from one end of the weld;

[0009] The weld image after scanning welding is acquired in real time, and the weld image is filtered to obtain a two-dimensional image;

[0010] Analyze the line contours in the two-dimensional image, find the lines that meet the features through edge detection and contour extraction, identify the position of the weld, build an XY two-dimensional coordinate system in the two-dimensional image, and obtain the absolute coordinates of the weld. When the actual position of the weld changes, adjust the position of the laser welder according to the absolute coordinates of the weld so that the error between the real-time weld position and the absolute coordinates is within the set range, thereby achieving dynamic and accurate tracking.

[0011] Four guiding mechanisms are arranged on the work surface, and the four guiding mechanisms respectively guide and position the plate from the four sides. A downward pressure cylinder is arranged to press the plate from top to bottom, and a lifting cylinder is used to keep the first plate and the second plate at the same height.

[0012] During the laser welding process, an air blow pipe is used to purge and cool the lens of the laser welder.

[0013] After welding, the weld is purged from the side with inert gas to isolate and protect the weld.

[0014] The guide mechanism comprises a guide plate and a guide wheel. The guide wheel is mounted on the guide plate, and the first plate and the second plate are pushed and tightened by the guide wheel.

[0015] A three-axis moving mechanism is set to drive the laser welder to move, so that the laser welder can adjust its position in real time and adjust the laser emission position so that the laser can accurately scan the weld.

[0016] Several guide mechanisms are arranged on the work surface along the length direction to guide and position the plate at different length positions.

[0017] When the laser welder emits a line laser to scan the weld, it obtains the current weld image in the welding process in real time, and obtains the line contour of the current weld image in real time, and compares it with the original line contour. If the line contour of the current weld image is inconsistent with the original line contour, the position of the laser welder is adjusted.

[0018] Compared with the prior art, the present invention has the following beneficial technical effects:

[0019] 1. On this structure, the four-sided guiding effect solves the working deviation technology caused by the deformation of the weld when feeding super-long materials over 9 meters.

[0020] 2. In this mechanism, the use of circulating air blowing technology ensures that the lens is not easily burned, ensuring that the equipment can work stably and permanently.

[0021] 3. In this mechanism, the drag box side blowing is used to ensure isolation from the air during welding and to prevent oxidation after welding.

[0022] 4. In terms of welding technology, it is possible to achieve one-time welding of welds longer than 9 meters, thus improving welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a three-dimensional structural schematic diagram of the laser welding device involved in the present invention;

[0024] Figure 2 for Figure 1 A is an enlarged structural diagram;

[0025] Figure 3 It is a schematic diagram of the structure of the laser welder in the present invention. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0027] In the description of the present invention, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like are involved, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium. It can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] like Figure 1-3 As shown, a laser welding method for non-magnetic metal materials comprises the following steps:

[0030] The welding target object is a plate made of non-magnetic metal plate material with a length greater than or equal to 9 meters, so the weld formed is also greater than or equal to 9 meters. Welds of this length are usually called super-long welds.

[0031] On the work surface, the sides of the first plate and the second plate that need to be welded are spliced, and the first plate and the second plate are pressed to keep stable. The sides of the first plate and the second plate are spliced ​​to form a weld, and the weld is imaged and converted to obtain the original line profile of the weld. The guide mechanism is used to guide and position the sides of the first plate and the second plate. The guide mechanism includes a guide plate 2 and a guide wheel 3. The guide wheel 3 is mounted on the guide plate 2. The first plate and the second plate are pushed and pushed by the guide wheel. The contact between the roller and the plate can better contact and press the plate. The guide mechanism can solve the problem of material jamming caused by deformation of the incoming material. The disc-shaped cylinder can also be used to drive the piano keys to press down to form a compression on the plate. It has a 3-fold lever capacity, which reduces the problem of using high air pressure to flatten.

[0032] The laser welder 1 is started, and the laser welder 1 emits a laser to start scanning welding from one end of the weld, and scans along the weld until the entire weld is welded.

[0033] The weld image after scanning welding is acquired in real time, and the weld image is filtered to obtain a two-dimensional image.

[0034] Analyze the line contours in the two-dimensional image, find the lines that meet the features through edge detection and contour extraction, identify the position of the weld, construct an XY two-dimensional coordinate system in the two-dimensional image, obtain the absolute coordinates of the weld, and when the actual position of the weld changes, adjust the position of the laser welder according to the absolute coordinates of the weld so that the error between the real-time weld position and the absolute coordinates is within the set range, and dynamic and accurate tracking is achieved. Establish an XYZ coordinate system on the work surface, and establish the relationship between the XY two-dimensional coordinate system and the XYZ coordinate system. According to the calibration relationship between the two-dimensional XY axis image and the actual space, the specific ZY axis coordinates of the weld can be obtained. When using weld tracking for welding, there are certain errors in the installation of the line laser and the camera, and there are certain errors in the measurement process. There must also be errors in the coordinates of the machine. Since the weld is an absolute coordinate in the two-dimensional XY image, after the calibration relationship, when the weld position changes, you only need to adjust the position of the laser welder to get infinitely close to this absolute coordinate value, and dynamic and accurate tracking can be achieved.

[0035] During the laser welding process, an air blow pipe is used to purge and cool the lens of the laser welder. An air blow pipe 4 can be set on the laser welder to achieve circulating air blowing, ensuring that the lens is blown during the entire welding process, so that the temperature of the lens will not be too high, thereby playing a protective role and avoiding damage to the lens.

[0036] For the weld after welding, inert gas is used to blow from the side, which not only has an isolation effect during the welding process, but also can protect the welding for a period of time after the welding is completed, so that the color of the weld is consistent with that of the parent material, eliminating the problem of surface carbonization. A side blowing box 5 can be set on one side of the blowing pipeline 4, and side blowing is performed from the side blowing box 5.

[0037] A three-axis moving mechanism is set to drive the laser welder to move, so that the laser welder can adjust its position in real time and adjust the laser emission position so that the laser can accurately scan the weld.

[0038] When the laser welder emits a line laser to scan the weld, it obtains the current weld image in the welding process in real time, and obtains the line contour of the current weld image in real time, and compares it with the original line contour. If the line contour of the current weld image is inconsistent with the original line contour, the position of the laser welder is adjusted.

[0039] It should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A laser welding method for non-magnetic metal materials, characterized in that: The following steps are involved: The welding target object is a plate made of non-magnetic metal plate material with a length greater than or equal to 9 meters; On the work surface, the sides of the first plate and the second plate that need to be welded are spliced ​​together, the first plate and the second plate are pressed together to keep them stable, a weld is formed at the sides where the first plate and the second plate are spliced ​​together, an image of the weld is acquired, and the original line profile of the weld is obtained by conversion; The laser welder is started, and the laser welder emits a laser to start scanning welding from one end of the weld; The weld image after scanning welding is acquired in real time, and the weld image is filtered to obtain a two-dimensional image; Analyze the line contours in the two-dimensional image, find the lines that meet the features through edge detection and contour extraction, identify the position of the weld, build an XY two-dimensional coordinate system in the two-dimensional image, and obtain the absolute coordinates of the weld. When the actual position of the weld changes, adjust the position of the laser welder according to the absolute coordinates of the weld so that the error between the real-time weld position and the absolute coordinates is within the set range, thereby achieving dynamic and accurate tracking.

2. The laser welding method for non-magnetic metal materials according to claim 1, characterized in that: Four guiding mechanisms are arranged on the work surface, and the four guiding mechanisms respectively guide and position the plate from the four sides. A downward pressure cylinder is arranged to press the plate from top to bottom, and a lifting cylinder is used to keep the first plate and the second plate at the same height.

3. The laser welding method for non-magnetic metal materials according to claim 1, characterized in that: During the laser welding process, an air blow pipe is used to purge and cool the lens of the laser welder.

4. The laser welding method for non-magnetic metal materials according to claim 1, characterized in that: After welding, the weld is purged from the side with inert gas to isolate and protect the weld.

5. The laser welding method for non-magnetic metal materials according to claim 2, characterized in that: The guide mechanism comprises a guide plate and a guide wheel. The guide wheel is mounted on the guide plate, and the first plate and the second plate are pushed and tightened by the guide wheel.

6. The laser welding method for non-magnetic metal materials according to claim 1, characterized in that: A three-axis moving mechanism is set to drive the laser welder to move, so that the laser welder can adjust its position in real time and adjust the laser emission position so that the laser can accurately scan the weld.

7. The laser welding method for non-magnetic metal materials according to claim 2, characterized in that: Several guide mechanisms are arranged on the work surface along the length direction to guide and position the plate at different length positions.

8. The laser welding method for non-magnetic metal materials according to claim 1, characterized in that: When the laser welder emits a line laser to scan the weld, it obtains the current weld image in the welding process in real time, and obtains the line contour of the current weld image in real time, and compares it with the original line contour. If the line contour of the current weld image is inconsistent with the original line contour, the position of the laser welder is adjusted.

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