Steel plate laser welding method and laser-welded section steel thereof

Abstract

The invention provides a steel plate laser welding method and section steel welded by the same. The steel plate laser welding method comprises the following steps: forming a joint area between a first steel plate and a second steel plate; laser is used for welding the joint area from one side of the second steel plate, so that the first steel plate and the second steel plate are combined to form section steel; the laser power of the laser ranges from 10000 watts to 25000 watts, so that a welding bead formed in the joint area after laser welding has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width ranges from 1 to 5. Therefore, the process can be effectively simplified, the welding time is saved, and the machining area is reduced.

Description

Technical Field

[0001] The invention relates to a steel plate laser (laser) welding method and a laser welded steel section. Background Art

[0002] H-shaped steel and T-shaped steel are common steel materials used in the construction industry and various manufacturing industries. For example, T-shaped steel is formed by spot welding two steel plates and then welding them back and forth multiple times using electric welding. Not only is the process complicated and time-consuming, but the steel plates are also prone to deformation due to being exposed to high temperatures of electric welding for a long time.

[0003] Therefore, there is a technology that uses laser welding. For example, Japanese Patent Publication No. JP2005021912A provides a "H-shaped steel welding method", which mainly uses a carbon dioxide gas laser or a YAG laser to weld metal plates to obtain H-shaped steel or T-shaped steel without overheating and deformation of the metal plates.

[0004] However, the power of CO2 laser and YAG laser is relatively low. When the thickness of the metal plate is relatively thick, for example, more than 10 mm, it is difficult for CO2 laser and YAG laser to penetrate the metal plate to complete welding. The thicker metal plate still needs to be welded by traditional electric welding. Summary of the invention

[0005] Therefore, the present invention provides a steel plate laser welding method and a steel section welded by laser welding.

[0006] The present invention provides a steel plate laser welding method, comprising: connecting a first steel plate and a second steel plate at a joint angle, wherein the thickness of the second steel plate is between 8 and 20 mm, and a joint area is formed between the first steel plate and the second steel plate; welding the joint area from one side of the second steel plate with a laser, wherein the laser and the first steel plate are provided with a welding angle, thereby combining the first steel plate and the second steel plate to form a steel section; the laser diameter of the laser is between 0.1 and 0.5 mm, and the laser power of the laser is between 10,000 and 25,000 watts, so that a weld bead is formed in the joint area after the laser welding, and the weld bead has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width is between 1 and 5.

[0007] The present invention also provides another steel plate laser welding method, comprising: connecting a first steel plate and a second steel plate at a joint angle, wherein the thickness of the second steel plate is between 8 and 40 mm, and a joint area is formed between the first steel plate and the second steel plate; welding the joint area with two lasers: welding the joint area with one laser from one side of the second steel plate, and the one laser and the first steel plate are sandwiched at a welding angle; and welding the joint area with another laser from the other side of the second steel plate, and the other laser and the first steel plate are sandwiched at the welding angle, so that the first steel plate and the second steel plate are combined to form a steel section; the laser diameter of the laser is between 0.1 and 0.5 mm, and the laser power of the laser is between 10,000 and 25,000 watts, so that a weld is formed in the joint area after the laser welding, and the weld has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width is between 1 and 5.

[0008] Furthermore, when the laser is used to weld the joining region, the laser is used to melt the first steel plate and / or the second steel plate, thereby joining the first steel plate and the second steel plate.

[0009] Wherein, the laser is a fiber laser or a disk laser.

[0010] When the laser is welding the joint area, the moving speed of the laser is between 5 and 30 mm per second, and the welding angle is between 5 and 20 degrees.

[0011] When the laser is used to weld the joint area from both sides of the second steel plate, the laser power on both sides is different.

[0012] The present invention further provides a laser-welded steel section, comprising: a first steel plate; and a second steel plate, which is connected to the first steel plate at a joint angle, a joint area is formed between the first steel plate and the second steel plate, and the second steel plate is combined with the first steel plate after laser welding the joint area; the thickness of the second steel plate is between 8 and 20 mm, the laser diameter of the laser is between 0.1 and 0.5 mm, and the laser power of the laser is between 10,000 and 25,000 watts, so that a weld bead formed in the joint area after the laser welding has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width is between 1 and 5.

[0013] When the laser is welding the joint area, the moving speed of the laser is between 5 and 30 mm per second, and the welding angle of the laser is between 5 and 20 degrees.

[0014] The laser is a fiber laser or a disk laser.

[0015] According to the above technical features, the following effects can be preferably achieved:

[0016] 1. By using lasers with a laser power between 10,000 and 25,000 watts, for steel plates with a thickness of 8 to 40 mm, the process can be effectively simplified, welding time can be saved, and the processing area can be reduced.

[0017] 2. Welding both sides of the second steel plate can avoid deformation caused by temperature difference on both sides of the second steel plate.

[0018] 3. When welding the two sides of the second steel plate, the laser power on both sides can be different, thereby avoiding uneven welding or incomplete joining of the overlapping points of the welds on both sides, and also saving energy.

[0019] 4. By selecting the welding angle, the surface shape of the weld can be controlled without using welding wire, and the thickness of the second steel plate can also be adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flowchart of the first embodiment of the present invention.

[0021] Figure 2 It is an exploded view of the first embodiment of the present invention, illustrating the first steel plate and the second steel plate.

[0022] Figure 3 It is one of the implementation schematic diagrams of the first embodiment of the present invention, illustrating welding of the joint area.

[0023] Figure 4 This is the second implementation schematic diagram of the first embodiment of the present invention, illustrating the joint area after welding.

[0024] Figure 5 This is the third schematic diagram of the implementation of the first embodiment of the present invention, showing the welded steel section.

[0025] Figure 6 It is one of the implementation schematic diagrams of the second embodiment of the present invention, illustrating that the joint area is welded simultaneously from both sides of the second steel plate.

[0026] Figure 7 This is the second schematic diagram of the implementation of the second embodiment of the present invention, showing the welded steel section.

[0027] Figure 8 This is one of the photographs of the second embodiment of the present invention, illustrating a weld bead after single-side welding.

[0028] Fig. 9 This is the second photo of the second embodiment of the present invention, illustrating the weld after double-sided welding.

[0029] Fig.10 It is one of the photos of the prior art, showing the weld after double-sided welding.

[0030] Fig.11 This is the second photo of the prior art, showing the steel specimen after stretching.

[0031] Fig.12 is a photograph of the first embodiment of the present invention, showing the steel test piece after stretching.

[0032] Explanation of the accompanying drawings: 100, 100a-steel; 1, 1a-first steel plate; 2, 2a-second steel plate; 3, 3a-fiber laser; 4, 4a-third steel plate; A-joining area; B-weld bead; C-welding depth; D-welding width; T1, T2-thickness; θ1-joining angle; θ2-welding angle. DETAILED DESCRIPTION

[0033] Based on the above technical features, the main effects of the steel plate laser welding method and the laser welded steel sections of the present invention can be clearly presented in the following embodiments.

[0034] See also Figures 1 to 3 , is a first embodiment of the steel plate laser welding method of the present invention, to produce the laser (laser) welded steel section of the present invention (hereinafter referred to as steel section 100), the steel section 100 as Figure 5 shown.

[0035] The steel plate laser welding method comprises the following steps:

[0036] A first steel plate 1 and a second steel plate 2 are connected at a connection angle θ1, and a connection area A is formed between the first steel plate 1 and the second steel plate 2. In this embodiment, the connection angle θ1 is 90 degrees.

[0037] In actual implementation, in order to facilitate subsequent welding, a weld gap may exist between the first steel plate 1 and the second steel plate 2 , so that the first steel plate 1 and the second steel plate 2 are connected across the weld gap.

[0038] In this embodiment, the thickness T1 of the second steel plate 2 is between 8 and 20 mm.

[0039] Next, a laser is used to weld the joint area A from one side of the second steel plate 2, and the laser and the first steel plate 1 form a welding angle θ2. Preferably, the welding angle θ2 is between 5 and 20 degrees. In the preferred embodiment of the present invention, the laser is an optical fiber laser 3, but a disk laser may be used instead in actual implementation.

[0040] The laser diameter of the fiber laser 3 is between 0.1 and 0.5 mm, the laser power of the fiber laser 3 is between 10,000 and 25,000 watts, and the moving speed of the fiber laser 3 is between 5 and 30 mm per second.

[0041] See also Figure 1 , Figures 3 to 5 After the fiber laser welding 3, the first steel plate 1 and / or the second steel plate 2 will be melted in the joint area A due to the fiber laser 3, so that the first steel plate 1 and the second steel plate 2 are combined with each other, and the molten part will form a weld bead B in the joint area A after cooling, and the first steel plate 1 and the second steel plate 2 will jointly form a T-shaped T-steel.

[0042] By selecting the welding angle θ2, the surface morphology of the weld bead B can be controlled without using welding wire, and the thickness T1 of the second steel plate 2 can also be adjusted. For example, a thicker second steel plate 2 can use a smaller welding angle θ2 to ensure the welding effect.

[0043] At Figure 5 The steel section 100 is shown as being H-shaped after being combined with a third steel plate 4. The combination method between the third steel plate 4 and the second steel plate 2 is the same as the combination method between the first steel plate 1 and the second steel plate 2, and will not be repeated here.

[0044] The weld bead B has a welding depth C along the first steel plate 1 and a welding width D obliquely along the second steel plate 2 , and a ratio of the welding depth C to the welding width D is between 1 and 5.

[0045] See also Figure 6 and Figure 7 , and please match Figure 1 , is a second embodiment of the steel plate laser welding method of the present invention. The difference between this embodiment and the first embodiment is that: in the first embodiment, the first embodiment is suitable for the second steel plate 2 with a thickness T1 between 8 and 20 mm [the first embodiment please match Figure 3 ], and when the thickness T2 of the second steel plate 2a reaches 20 to 40 mm, the steel plate laser welding method of this embodiment is more suitable. In actual implementation, Figure 3 The second steel plate 2 can also adopt the steel plate laser welding method of this embodiment.

[0046] Similar to the first embodiment, the first steel plate 1 a and the second steel plate 2 a are first connected at the connection angle θ1 to form the connection area A between the first steel plate 1 a and the second steel plate 2 a .

[0047] Then, two groups of the fiber laser 3a are used to simultaneously weld the joint area A from both sides of the second steel plate 2a, and the two groups of the fiber laser 3a and the first steel plate 1a both have the welding angle θ2, thereby combining the first steel plate 1a and the second steel plate 2a to form a T-shaped steel.

[0048] Preferably, the welding of the two sides of the second steel plate 2a is performed simultaneously, and the laser powers on the two sides are different. The drawings of the present invention are only for illustration. Figure 7 The steel section 100a is shown as being H-shaped after being combined with the third steel plate 4a.

[0049] Welding both sides of the second steel plate 2a can not only ensure that the first steel plate 1a is firmly bonded to the second steel plate 2a, but also avoid deformation of the second steel plate 2a due to temperature difference on both sides of the second steel plate 2a when only one side is welded.

[0050] The laser powers on both sides are different, which can avoid uneven welding or incomplete joining of the overlapping points of the welds B on both sides. When the thickness T2 of the second steel plate 2a is thinner, using lower power on one side can also save energy.

[0051] The parameters of the optical fiber laser 3a and the welding process may be in the same range as those of the first embodiment, and will not be repeated here.

[0052] See also Figures 8 to 10 , and please match Figure 4 , Figure 8 It is a T-shaped steel with only one side welded. Fig. 9 The T-shaped steel is welded on both sides by the steel plate laser welding method of the second embodiment of the present invention. Fig.10 It is a T-shaped steel welded by electric welding using conventional technology.

[0053] It can be clearly seen from the comparison of the photos that the prior art has welding defects such as pores and poor melting, while the present invention has a more uniform welding effect, which can effectively simplify the process, save welding time, and reduce the processing area.

[0054] from Figure 8 The markings in FIG. 2 also confirm that the ratio of the welding depth C to the welding width D is indeed between 1 and 5, and that the welding depth C can indeed reach about 20 mm.

[0055] See also Fig.11 and Fig.12 , and the tensile test method of AWS D1.1 / D1.1M (2020) of Taiwan Inspection Technology Co., Ltd. was used to test two sets of conventional submerged arc welding (SAW) steel specimens (see Fig.11), and two sets of steel specimens using the steel plate laser welding method of the first embodiment (see Fig.12 ), the test results are shown in Table 1. Fig.11 and Fig.12 As shown:

[0056] Table 1 Tensile test results

[0057]

[0058] See also Figure 3 and Figure 4 , and please match Fig.11 and Fig.12 From the above test, the steel sections all broke from the middle of the second steel plate 2 rather than from the joint area B. It can be known that after using the steel plate laser welding method, the weld B does have sufficient strength as the conventional submerged arc welding.

[0059] Taking H-shaped combined steel (BH) as an example, in terms of production speed, the prior art takes more than 4 hours to weld each combined steel, while the present invention can complete the welding of one combined steel within 20 minutes.

[0060] In terms of manpower, for every 3,000 tons of combined steel, the conventional technology requires 6 people to perform welding operations, while the present invention only requires one person to perform welding operations.

[0061] In addition to increasing production speed and reducing labor costs, compared with the prior art, the present invention can also save 80% of welding materials and reduce 70% of carbon emissions.

[0062] Based on the description of the above embodiments, one should be able to fully understand the operation, use and effects of the present invention. The above embodiments are only preferred embodiments of the present invention and should not be used to limit the scope of implementation of the present invention. That is, all simple equivalent changes and modifications made according to the claims and description of the present invention are within the scope of the present invention.

Claims

1. A steel plate laser welding method, characterized in that: Include: A first steel plate and a second steel plate are connected at a joint angle, and the thickness of the second steel plate is between 8 and 20 mm, and a joint area is formed between the first steel plate and the second steel plate; The joint area is welded by a laser from one side of the second steel plate, and the laser and the first steel plate are provided with a welding angle, so that the first steel plate and the second steel plate are combined to form a steel section; The laser diameter of the laser is between 0.1 and 0.5 mm, and the laser power of the laser is between 10,000 and 25,000 watts, so that after laser welding, a weld is formed in the joint area, and the weld has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width is between 1 and 5.

2. A steel plate laser welding method, characterized in that: Include: A first steel plate and a second steel plate are connected at a joint angle, and the thickness of the second steel plate is between 8 and 40 mm, and a joint area is formed between the first steel plate and the second steel plate; The joint area is welded with two lasers: Using one of the lasers to weld the joint area from one side of the second steel plate, and the one of the lasers and the first steel plate form a welding angle; and welding the joint area from the other side of the second steel plate with another laser, wherein the other laser and the first steel plate are sandwiched at the welding angle, so that the first steel plate and the second steel plate are combined to form a steel section; The laser diameter of the laser is between 0.1 and 0.5 mm, and the laser power of the laser is between 10,000 and 25,000 watts, so that after the laser welding, a weld is formed in the joint area, and the weld has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width is between 1 and 5.

3. The steel plate laser welding method according to claim 1 or 2, characterized in that: Furthermore, when the laser is used to weld the joining region, the laser is used to melt the first steel plate and / or the second steel plate, thereby joining the first steel plate and the second steel plate.

4. The steel plate laser welding method according to claim 1 or 2, characterized in that: The lasers are all fiber lasers or disk lasers.

5. The steel plate laser welding method according to claim 1 or 2, characterized in that: When the laser is welding the joint area, the moving speed of the laser is between 5 and 30 mm per second, and the welding angle is between 5 and 20 degrees.

6. The steel plate laser welding method according to claim 2, characterized in that: When the laser is used to weld the joint area from both sides of the second steel plate, the laser power on both sides is different.

7. A laser welded steel section, characterized in that: Include: a first steel plate; and A second steel plate is connected to the first steel plate at a joint angle, a joint area is formed between the first steel plate and the second steel plate, and the second steel plate is combined with the first steel plate after the joint area is welded by a laser; The thickness of the second steel plate is between 8 and 40 mm, the laser diameter of the laser is between 0.1 and 0.5 mm, and the laser power of the laser is between 10,000 and 25,000 watts, so that a weld is formed in the joint area after laser welding, and the weld has a welding depth along the first steel plate and a welding width along the second steel plate, and the ratio of the welding depth to the welding width is between 1 and 5.

8. The laser welded steel section according to claim 7, characterized in that: When the laser is welding the joint area, the moving speed of the laser is between 5 and 30 mm per second, and the welding angle of the laser is between 5 and 20 degrees.

9. The laser welded steel section according to claim 7, characterized in that: The laser is a fiber laser or a disk laser.

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