Flexible weld bead complete protection device and welding method

Abstract

The present invention relates to a flexible weld bead complete protection device and welding method, wherein the flexible weld bead complete protection device includes a protective cover, a first protective gas pipe, and a partition plate, wherein openings are formed at the lower and front ends of the protective cover, the partition plate is located inside the protective cover and fixed to the protective cover, the partition plate divides the inside of the protective cover into an upper chamber and a lower chamber, the protective cover and partition plate are expandable and contractible, and the exhaust port of the first protective gas pipe is located inside the lower chamber. The compressed air of the present invention blows below the protective lens, enters the upper chamber, flows within the upper chamber, and generates negative pressure, thereby drawing high-temperature welding fumes into the upper chamber, moving the welding fumes away from above the welding site, reducing the adverse effect of welding fumes on the weld bead, and preventing welding fumes from blocking the laser light emitted from the laser head.

Description

Technical Field

[0001] The present invention relates to the field of welding bead protection, and particularly to a flexible welding bead complete protection device and a welding method.

Background Art

[0002] Laser welding has advantages such as highly concentrated energy, a small heat affected zone, and small post-welding deformation, and has been widely applied in the metal industry such as carbon steel, stainless steel, aluminum alloy, titanium alloy, etc. In the laser welding process, if the welding bead of a metal that is prone to oxidation is not effectively protected, oxidation and ablation are likely to occur, further affecting the performance of the welding bead. Commonly used coaxial protection devices or side-blowing protection devices can only guarantee effective protection of the liquid molten pool and molten droplet metal, and the welding bead metal immediately after solidification and the high-temperature adjacent bead part after welding are not effectively protected. When the welding bead metal immediately after solidification and the high-temperature adjacent bead part cool in the atmospheric environment, they react with oxygen, nitrogen, hydrogen, etc. in the air. In mild cases, oxidation and discoloration occur, and in severe cases, it may even lead to embrittlement of the welding bead and a decrease in the plasticity of the welding bead.

[0003] In addition, the welding fumes generated during welding are located above the welded member, affecting the quality of the welding bead, blocking the laser light emitted from the laser head and causing a decrease in output energy, and damaging the respiratory system of nearby workers.

Summary of the Invention

[0004] The present invention is made to solve the above problems, and provides a flexible welding bead complete protection device and a welding method, solving the problems of oxidation, discoloration, and performance degradation of the welding bead.

[0005] A flexible weld bead complete protection device comprising a protective cover, a first protective gas pipe, and a partition plate, wherein openings are formed at the lower and front ends of the protective cover, the partition plate is located inside the protective cover and fixed to the protective cover, the partition plate divides the inside of the protective cover into an upper chamber and a lower chamber, the protective cover and partition plate are expandable and contractible, and the exhaust port of the first protective gas pipe is located inside the lower chamber.

[0006] Based on the above technical plan, the system further includes compressed gas piping in which the exhaust port is located inside the upper chamber.

[0007] Based on the above technical plan, the invention further includes a first guide plate and a second guide plate, The first guide plate is located on the front side of the protective cover, the rear side of the first guide plate is higher than the front side, and the upper part of the first guide plate communicates with the upper chamber. The second guide plate is located above the first guide plate, and the compressed gas piping is fixedly connected to the second guide plate by passing through it. The positions of the first guide plate and the second guide plate are fixed relative to the front end of the protective cover.

[0008] Based on the above technical solution, the protective cover further includes a first fixing frame and a second fixing frame, the front and rear ends of the protective cover are fixedly connected to the first fixing frame and the second fixing frame, respectively, and the first guide plate and the second guide plate are fixedly connected to the first fixing frame, respectively.

[0009] Based on the above technical plan, the invention further includes a first shielding plate, a second shielding plate, and an exhaust pipe, The first shielding plate and the second fixing frame are fixedly connected, and the first shielding plate shields the rear end of the lower chamber; the second shielding plate and the first fixing frame are fixedly connected, and the second shielding plate shields the front end of the lower chamber; The rear end of the first protective gas piping passes through the first shielding plate, and the exhaust pipe and the exhaust port of the first protective gas piping are fixedly connected and in communication. The exhaust pipe is located inside the lower chamber and its exhaust port faces downward, and the position of the exhaust pipe is fixed with respect to the first fixed frame.

[0010] Based on the above technical plan, the system further includes side plates, the two side plates being located on the left and right sides of the first guide plate and the second guide plate, respectively, and the upper and lower sides of the side plates being fixedly connected to the second guide plate and the first guide plate, respectively, forming an intake passage surrounded by the first guide plate, the second guide plate and the two side plates.

[0011] Based on the above technical plan, the protective cover is a bellows-type protective cover, the partition plate is a folding plate, and the first protective gas piping is expandable and retractable.

[0012] Based on the above technical solution, the protective cover further includes a band seal, and both lower ends of the protective cover are fixedly connected to the band seal.

[0013] Step S1 involves placing the welding member on top of the welding table and cleaning the welding area of ​​the welding member. Step S2 involves connecting the laser head to the front end of the protective cover, fixing the rear end of the protective cover to the welding table, and connecting the rear end of the lower chamber to the intake port of the exhaust gas treatment device. Compressed air is supplied from the intake port of the laser head, and after passing below the protective lens of the laser head, the compressed air leaves the intake port and enters the compressed gas piping before entering the upper chamber. Step S3 involves supplying protective gas to the first protective gas piping and the second protective gas piping, The laser head is moved along the welding direction to weld the weld members, and the front ends of the first protective gas pipe and protective cover follow the movement on both the front and rear sides of the laser head, respectively, and the protective cover covers the top of the weld bead in step S4, A welding method using the flexible weld bead complete protection device, comprising step S5, which involves shutting off the protective gas in the first protective gas piping and the second protective gas piping, and the compressed air in the air intake, and stopping the laser head after welding is complete.

[0014] Based on the above technical plan, if the welding direction is changed, stopper sliders are installed on both sides of the point where the welding direction is changed before welding to restrict the movement of the protective cover. If rapid cooling of the weld bead is required, a second protective gas pipe is used to supply the cooling protective gas.

[0015] The present invention has the following advantages. 1. After welding, a protective atmosphere is formed on the weld bead metal immediately after solidification and on the high-temperature adjacent bead area. Additionally, all weld beads are covered with an expandable protective cover, thereby achieving complete protection of the entire weld bead during the cooling process and preventing oxidation, discoloration, and performance degradation of the weld bead. 2. Compressed air blows below the protective lens, then enters the upper chamber and flows through it, generating negative pressure. This draws high-temperature welding fumes into the upper chamber, keeping them away from the welding area, reducing their adverse effect on the weld bead, and preventing them from blocking the laser beam emitted from the laser head. 3. The airflow ejected from the second protective gas piping facilitates the separation of welding fumes and protective gases due to their temperature differences, thereby reducing the amount of protective gas drawn into the upper chamber. 4. For welded components requiring rapid cooling, the protective gas from the second protective gas piping is cooled before being ejected to cool the weld bead and simultaneously increase the temperature difference between the protective gas and the welding fume, thereby achieving better layer separation between the two. 5. The protective cover is flexible, and with the movement restriction action of the stopper slider, the protective cover can be bent, thereby adapting to the bending welding direction. [Brief explanation of the drawing]

[0016] To clearly explain the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the following description of the embodiments or the prior art will be briefly described. The drawings in the following description are only one embodiment of the present invention, and it is obvious to those skilled in the art that other drawings can be derived based on the provided drawings without creative work. [Figure 1] It is a schematic top view of the upper surface structure of the present invention. [Figure 2] It is a schematic cross-sectional structure view taken along A-A in FIG. 1. [Figure 3] It is a schematic three-dimensional structure view of one of the present inventions. [Figure 4] It is a schematic partial enlarged structure view at B in FIG. 3. [Figure 5] It is another schematic three-dimensional structure view of the present invention. [Figure 6] It is a schematic top view of the upper surface structure of the stopper-slider.

Mode for Carrying Out the Invention

[0017] Hereinafter, the present invention will be further described with reference to the drawings and examples.

[0018] Hereinafter, the embodiments of the present invention will be described in detail. The embodiments are shown in the drawings. In all the drawings, the same or similar reference numerals indicate the same or similar elements, or elements having the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and should not be construed as limiting the present invention.

[0019] In the description of the present invention, unless there are clear regulations or limitations, the terms "attachment", "connection", and "connection" should be interpreted broadly. For example, they may be fixedly connected, removably connected, or integrally connected, may be directly connected, or may be indirectly connected through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific situation.

[0020] In the description of this invention, terms such as "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," and "outside" refer to directions or positional relationships based on the directions or positional relationships shown in the drawings. These terms are merely for the purpose of simplifying the description and mention of this invention and do not indicate or suggest that the shown devices or elements have a specific direction or must be configured and operated in a specific direction. Therefore, it should be understood that these terms should not be interpreted as limiting the invention.

[0021] Example 1: As shown in Figures 1 to 6, this embodiment provides a flexible weld bead complete protection device, which includes a protective cover 1, a first protective gas pipe 2, and a partition plate 10. The protective cover 1 has openings at its lower and front ends, the partition plate 10 is located inside the protective cover 1 and fixed to it, the partition plate 10 divides the inside of the protective cover 1 into an upper chamber 11 and a lower chamber 12, the protective cover 1 and the partition plate 10 are expandable and contractible, and the exhaust port of the first protective gas pipe 2 is located inside the lower chamber 12.

[0022] Based on the above technical plan, the system further includes a compressed gas piping 5 whose exhaust port is located inside the upper chamber 11. Preferably, the exhaust port of the compressed gas piping 5 is located at the front of the upper chamber 11.

[0023] Based on the above technical solution, a first guide plate 3 is further included, wherein the first guide plate 3 is located on the front side of the protective cover 1, the rear side of the first guide plate 3 is higher than the front side, the upper part of the first guide plate 3 is in communication with the upper chamber 11, and the first guide plate 3 plays a role in guiding welding fumes.

[0024] The system further includes a second guide plate 4, the second guide plate 4 being located above the first guide plate 3, and the compressed gas piping 5 being fixedly connected to the second guide plate 4 through the second guide plate 4. The positions of the first guide plate 3 and the second guide plate 4 are fixed to the front end of the protective cover 1, respectively.

[0025] Based on the above technical solution, the protective cover 1 further includes a first fixing frame 13 and a second fixing frame 14, the front and rear ends of the protective cover 1 are fixedly connected to the first fixing frame 13 and the second fixing frame 14, respectively, and the first guide plate 3 and the second guide plate 4 are fixedly connected to the first fixing frame 13, respectively.

[0026] Based on the above technical plan, the system further includes a first shielding plate 15, a second shielding plate 31, and an exhaust pipe 21. The first shielding plate 15 and the second fixing frame 14 are fixedly connected, and the first shielding plate 15 shields the rear end of the lower chamber 12. The second shielding plate 31 and the first fixing frame 13 are fixedly connected, and the second shielding plate 31 shields the front end of the lower chamber 12. The rear end of the first protective gas piping 2 passes through the first shielding plate 15, and the exhaust pipe 21 and the exhaust port of the first protective gas piping 2 are fixedly connected and in communication. The exhaust pipe 21 is located inside the lower chamber 12 and its exhaust port faces downward, and the position of the exhaust pipe 21 is fixed with respect to the first fixing frame 13.

[0027] Based on the above technical plan, the system further includes side plates 41, the two side plates 41 being located on the left and right sides of the first guide plate 3 and the second guide plate 4, respectively, and the upper and lower sides of the side plates 41 being fixedly connected to the second guide plate 4 and the first guide plate 3, respectively, forming an intake passage surrounded by the first guide plate 3, the second guide plate 4 and the two side plates 41. The intake passage reduces the diffusion of welding fumes to the outside and allows as many fumes as possible to enter the intake passage and the upper chamber 11.

[0028] Based on the above technical solution, the protective cover 1 is a bellows-type protective cover, and the first protective gas piping 2 is expandable and retractable. The first protective gas piping 2 is a Bourdon tube. Preferably, the protective cover 1 and the partition plate 10 are made of aluminum foil, and the partition plate 10 is a folding plate.

[0029] Based on the above technical solution, a band seal 6 is further included, and the lower ends on both sides of the protective cover 1 are fixedly connected to the band seal 6. Preferably, the shape of the band seal 6 is zigzag to conform to the shape of the protective cover 1, and the band seal 6 is foldable.

[0030] A welding method using the flexible weld bead complete protection device, comprising the following steps S1 to S5. In step S1, the welding member 9 is placed on top of the welding table, and the welding area of ​​the welding member 9 is cleaned. In step S2, the laser head 7 is connected to the front end of the protective cover 1, the rear end of the protective cover 1 is fixed to the welding table, the rear end of the lower chamber 12 is connected to the intake port of the exhaust gas treatment device, and preferably the second fixing frame 14 or the first shielding plate 15 is fixedly connected to the welding table. In step S3, compressed air is supplied from the intake port 71 of the laser head 7. The compressed air passes below the protective lens 73 of the laser head 7, then leaves the intake port 71, enters the compressed gas piping 5, and then enters the upper chamber 11. A protective gas is supplied to the first protective gas piping 2 and the second protective gas piping 8, preferably the protective gas being argon. In step S4, the laser head 7 is moved along the welding direction to weld the welding member 9, and the front ends of the first protective gas pipe 2 and the protective cover 1 follow the movement of the laser head 7 on both the front and rear sides, respectively, and the protective cover 1 covers the top of the weld bead 91, preferably the laser head 7 is fixedly connected to the front end of the protective cover 1, the second guide plate 4, or the first fixed frame 13, or is hinged to it. In step S5, after welding is complete, the protective gases in the first protective gas piping 2 and the second protective gas piping 8, and the compressed air in the air intake 71 are shut off, and the laser head 7 is stopped. Preferably, the protective gas in the first protective gas piping 2 is shut off last, after the weld bead has almost cooled, thereby maintaining the protective gas concentration in the lower chamber 12.

[0031] Based on the above technical plan, when the welding direction is changed (as shown in Figure 6), stopper sliders 16 are installed on both sides of the point where the welding direction is changed before welding. The protective cover 1 moves between the stopper sliders 16 on both sides and comes into contact with the stopper sliders 16. The stopper sliders 16 are used to restrict the movement of the protective cover 1, and the position of the stopper sliders 16 is fixed with respect to the welding table or rotates around its own axis.

[0032] If the weld bead 91 needs to be cooled rapidly, the cooled protective gas is supplied to the second protective gas pipe 8, and the temperature of the protective gas is lower than room temperature.

[0033] Operating principle: During welding, compressed air blows below the protective lens 73, keeping the welding fumes generated by welding away from below the protective lens 73, preventing the fume particles from covering the protective lens 73 and blocking the laser beam. The compressed air, along with the welding fumes, then exits the inside of the laser head 7 through the exhaust port 72. Subsequently, the compressed air passes through the vent pipe and the compressed gas piping 5 in sequence. After leaving the outlet of the compressed gas piping 5, the compressed air flows from front to back. The compressed gas piping 5 flows at high speed into the upper chamber 11, generating negative pressure which draws the fumes from above the welding site. The fumes then move from front to back in the upper chamber 11 until they enter the exhaust gas treatment device and are processed.

[0034] During the welding process, argon ejected from the second protective gas pipe 8 forms a gas layer flowing from front to back above the welding area, thereby separating the welding fumes from the welding area. Although the temperature of the fumes generated from welding is high, the temperature of argon is lower than that of the fumes, which is advantageous for separating the layers of the two. Furthermore, the high-temperature fumes spontaneously move upward, and the fumes are drawn into the upper chamber 11.

[0035] After passing through the welding area, the argon gas travels between the first guide plate 3 and the welded member 9, protecting the weld bead 91. Because there is a gap between the second shielding plate 31 and the welded member 9, the protective gas that overflows from the gap without stopping the weld bead 91 reaches the area between the first guide plate 3 and the second shielding plate 31, further protecting the weld bead 91.

[0036] The exhaust pipe 21 ejects a protective gas (e.g., argon) downwards, so that the area above the weld bead 91 is filled with the protective gas instead of air, preventing the weld bead 91 from reacting with oxygen, nitrogen, hydrogen, etc., in the air immediately after solidification. The lower end opening of the protective cover 1 is sealed by the welding member 9, and the band seal 6 is in contact with the upper surface of the welding member 10, further improving the sealing effect. At this time, the protective gas in the lower chamber 12 can only overflow through the gap between the front second shielding plate 31 and the welding member 9, thus reducing the overflow of protective gas from the lower chamber 12 and improving the protective gas content above the weld bead 91.

[0037] By supplying thermal protection gas or hot air to the first protective gas pipe 2, slow cooling of the weld bead can be achieved, making it suitable for welding high-alloy steel materials such as nickel-based steels. By supplying cooling water to the first protective gas pipe 2, rapid cooling of the weld bead can be achieved, making it suitable for welding high-strength steels and ultra-high-strength steels where the weld bead structure is required.

[0038] Furthermore, the protective cover 1 and the first protective gas pipe 2 may expand and contract in a straight line or in a curved line.

[0039] In this application, "expandable" refers to the ability to change the distance between the ends of components such as the protective cover 1, protective gas pipe 2, and partition plate 10.

[0040] Although the present invention has been described with examples above, the present invention is not limited to the specific embodiments described above, and any modifications or variations based on the present invention are all within the scope of protection of the present invention.

Claims

1. A flexible weld bead complete protection device comprising a protective cover (1), a first protective gas pipe (2), and a partition plate (10), A flexible weld bead complete protection device, characterized in that openings are formed at the lower and front ends of the protective cover (1), the partition plate (10) is located inside the protective cover (1) and fixed to the protective cover (1), the partition plate (10) divides the inside of the protective cover (1) into an upper chamber (11) and a lower chamber (12), the protective cover (1) and the partition plate (10) are expandable and contractible, and the exhaust port of the first protective gas pipe (2) is located inside the lower chamber (12).

2. The flexible weld bead complete protection device according to claim 1, further comprising a compressed gas pipe (5) whose exhaust port is located inside the upper chamber (11).

3. The present invention further includes a first guide plate (3) and a second guide plate (4), The first guide plate (3) is located on the front side of the protective cover (1), the rear side of the first guide plate (3) is higher than the front side, and the upper part of the first guide plate (3) is in communication with the upper chamber (11). The second guide plate (4) is located above the first guide plate (3), and the compressed gas piping (5) is fixedly connected to the second guide plate (4) by passing through the second guide plate (4). The flexible weld bead complete protection device according to claim 2, characterized in that the positions of the first guide plate (3) and the second guide plate (4) are fixed to the front end of the protective cover (1).

4. Further including a first fixed frame (13) and a second fixed frame (14), The flexible weld bead complete protection device according to claim 3, characterized in that the front and rear ends of the protective cover (1) are fixedly connected to a first fixing frame (13) and a second fixing frame (14), respectively, and the first guide plate (3) and the second guide plate (4) are fixedly connected to the first fixing frame (13), respectively.

5. It further includes a first shielding plate (15), a second shielding plate (31), and an exhaust pipe (21), The first shielding plate (15) and the second fixing frame (14) are fixedly connected, and the first shielding plate (15) shields the rear end of the lower chamber (12). The second shielding plate (31) and the first fixing frame (13) are fixedly connected, and the second shielding plate (31) shields the front end of the lower chamber (12). The flexible weld bead complete protection device according to claim 4, characterized in that the rear end of the first protective gas pipe (2) passes through the first shielding plate (15), the exhaust pipe (21) is fixedly connected to and communicates with the exhaust port of the first protective gas pipe (2), the exhaust pipe (21) is located inside the lower chamber (12) and its exhaust port faces downward, and the position of the exhaust pipe (21) is fixed with respect to the first fixing frame (13).

6. Further including side panels (41), The flexible weld bead complete protection device according to claim 3, characterized in that the two side plates (41) are located on the left and right sides of the first guide plate (3) and the second guide plate (4), respectively, and the upper and lower sides of the side plates (41) are fixedly connected to the second guide plate (4) and the first guide plate (3), respectively, and an intake passage is formed surrounded by the first guide plate (3), the second guide plate (4) and the two side plates (41).

7. The flexible weld bead complete protection device according to claim 1, characterized in that the protective cover (1) is a bellows-type protective cover, the partition plate (10) is a folding plate, and the first protective gas pipe (2) is expandable and retractable.

8. Further including a band seal (8), The flexible weld bead complete protection device according to claim 1, characterized in that the lower ends on both sides of the protective cover (1) are fixedly connected to the strip seal (8).

9. Step S1 involves placing the welding member (9) on top of the welding table and cleaning the welding area of ​​the welding member (9), Step S2 involves connecting the laser head (7) to the front end of the protective cover (1), fixing the rear end of the protective cover (1) to the welding table, and connecting the rear end of the lower chamber (12) to the intake port of the exhaust gas treatment device. Compressed air is supplied from the intake port (71) of the laser head (7), and after passing below the protective lens (73) of the laser head (7), the compressed air leaves the intake port (71), enters the compressed gas piping (5), and then enters the upper chamber (11). Step S3 involves supplying protective gas to the first protective gas piping (2) and the second protective gas piping (8), The laser head (7) is moved along the welding direction to weld the welding member (9), and the first protective gas pipe (2) and the front end of the protective cover (1) follow the movement on both the front and rear sides of the laser head (7), and the protective cover (1) covers the top of the weld bead (91) in step S4, A welding method using a flexible weld bead complete protection device according to any one of claims 1 to 8, characterized by including step S5 of shutting off the protective gas in the first protective gas pipe (2) and the second protective gas pipe (8), and the compressed air in the air intake (71), and stopping the laser head (7) after welding is completed.

10. If the welding direction is to be changed, stopper sliders (16) are installed on both sides of the point where the welding direction is to be changed before welding to restrict the movement of the protective cover (1). The welding method according to claim 9, characterized in that, when it is necessary to rapidly cool the weld bead (91), the cooled protective gas is supplied to the second protective gas pipe (8).

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