Welding device and method integrating laser cleaning and laser arc hybrid welding

Abstract

The invention discloses a welding device and method integrating laser cleaning and laser arc hybrid welding. The welding device comprises a laser device, an optical splitter and a laser galvanometer which are connected through optical fibers. The laser is used for generating a beam of high-energy laser, and the high-energy laser is transmitted to the optical splitter through the optical fiber and is divided into two parts by the optical splitter; and the two beams of laser after light splitting are transmitted to the laser galvanometer through the optical fiber, and the laser galvanometer outputs two beams of laser with different laser scanning shapes to a workpiece to be welded. High-quality welding can be carried out on the welding seam of the steel bridge corrugated plate and the shear nail beam, and technical support is provided for construction of a novel bridge structure.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and in particular to a welding device and method integrating laser cleaning and laser arc hybrid welding. Background Art

[0002] In order to implement the new development concept and promote the new industrialization of bridge engineering construction, a dense beam H-shaped steel composite bridge structure with controllable overall cost, low resource consumption, low carbon and environmental protection, and convenient and fast construction has been designed. Except for the pile foundation, the rest of the structure of this bridge type is steel structure or steel-concrete composite structure. Steel boxes and steel pipes are used to replace a large number of construction templates of the original concrete structure. It has the characteristics of lightweight, simple and fast construction, and has great promotion value in small and medium span simply supported bridges.

[0003] During the construction of this steel composite bridge, the welding problem of the corrugated plate (material: Q235B) and the shear nail beam (material: 355NHC) will be involved. Since the bridge is built in an open-air environment, impurities such as rust, dust, and oil will appear on the surface of the weathering steel. At the same time, at the bend of the bridge, in order to ensure the stability of the vehicle during driving, there will be a height difference between the inside and outside of the bridge deck, which will cause the displacement of the corrugated plate and the shear nail beam, and a gap of no more than 8mm will appear at the weld between them. If these two problems are not dealt with, it will cause problems such as low welding efficiency, poor welding quality, and poor welding forming, resulting in substandard weld quality and affecting the safety of bridge use. Summary of the invention

[0004] In view of the above problems, the present invention aims to provide a welding device and method integrating laser cleaning and laser arc hybrid welding.

[0005] The technical solution of the present invention is as follows:

[0006] On the one hand, a welding device integrating laser cleaning and laser arc hybrid welding is provided, comprising a laser, a beam splitter and a laser galvanometer connected by an optical fiber;

[0007] The laser is used to generate a beam of high-energy laser, which is transmitted to the beam splitter through the optical fiber and split into two by the beam splitter; the two split laser beams are transmitted to the laser galvanometer through the optical fiber and the laser galvanometer outputs two laser beams with different laser scanning shapes to the workpiece to be welded.

[0008] Preferably, a half-mirror and a total reflection mirror are provided inside the beam splitter, and a beam of high-energy laser generated by the laser is divided into laser beam one and laser beam two through the half-mirror. Laser beam one directly enters the optical fiber and is transmitted to the laser galvanometer through the optical fiber, and laser beam two enters the optical fiber through the total reflection mirror and is transmitted to the laser galvanometer through the optical fiber.

[0009] Preferably, the semi-mirror comprises a laser-transmitting lens and a metal lattice arranged on the laser-transmitting lens, and the laser transmittance and laser reflectivity of the semi-mirror are adjusted by adjusting the density of the metal lattice.

[0010] Preferably, the laser light-transmitting lens is made of quartz, and the metal lattice is made of copper.

[0011] Preferably, the light intensity ratio of the laser beam one to the laser beam two is 3:7.

[0012] Preferably, the laser galvanometer comprises a shell, in which a motor 1 and a motor 2 are arranged, and the motor 1 and the motor 2 are connected to the total reflector through a transmission rod, and the total reflectors on the two motors are vertically parallel and relatively arranged.

[0013] Preferably, a protective lens is also provided at the output end of the laser galvanometer.

[0014] On the other hand, a welding method integrating laser cleaning and laser arc hybrid welding is also provided, and welding is performed using a welding device integrating laser cleaning and laser arc hybrid welding as described in any one of the above.

[0015] Preferably, the corrugated plate and the shear nail beam of the steel bridge are welded by using any one of the welding devices integrating laser cleaning and laser arc hybrid welding as described above.

[0016] Preferably, during welding, the laser scanning frequency is 50-150 Hz, the diameter of a single circle is 10-20 mm, the laser power is 1000-2000 W, the arc current is 200-350 A, the voltage is 20-35 V, and the welding speed is 4-10 mm / s.

[0017] The beneficial effects of the present invention are:

[0018] The present invention divides the input laser into two by arranging a beam splitter, wherein one beam of laser is responsible for laser cleaning of the weld to remove impurities such as rust, dust, oil, moisture, etc., to avoid the influence of impurities on weld formation and structure, and to improve weld quality; the other beam of laser is responsible for welding the weld in combination with the arc to enhance the weld such as input and guide the arc, and to increase the weld width, thereby realizing the functions of laser cleaning and laser-arc composite welding in one, thereby achieving the effect of high-quality welding of the welds of the corrugated plate and the shear nail beam of the steel bridge. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a structural schematic diagram of a welding device integrating laser cleaning and laser arc hybrid welding according to the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of the beam splitter of the welding device integrating laser cleaning and laser arc hybrid welding of the present invention;

[0022] Figure 3 It is a structural schematic diagram of a half-mirror of a welding device integrating laser cleaning and laser arc hybrid welding according to the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of the laser galvanometer of the welding device integrating laser cleaning and laser arc hybrid welding of the present invention;

[0024] Figure 5 It is a schematic diagram of the welding device integrating laser cleaning and laser arc hybrid welding of the present invention performing swing pulse laser-pulse current hybrid welding;

[0025] Figure 6 It is a schematic diagram of the principle of laser cleaning performed by the welding device integrating laser cleaning and laser arc hybrid welding of the present invention;

[0026] Figure 7 It is a schematic diagram of the mechanism of swing pulse laser-pulse current hybrid welding performed by the welding device integrating laser cleaning and laser arc hybrid welding of the present invention;

[0027] Figure 8 It is a schematic diagram of the morphology of a T-shaped weld joint of a joint without laser cleaning and laser welding in a specific embodiment;

[0028] Fig. 9 A schematic diagram of the morphology of a T-shaped weld joint of a laser cleaning and laser arc hybrid welding joint in a specific embodiment;

[0029] Fig.10 It is a schematic diagram of the tensile strength results of two T-weld joints in a specific embodiment; wherein a) is a schematic diagram of the results of the joint without laser cleaning and laser welding, and b) is a schematic diagram of the results of the joint with laser cleaning and laser welding arc hybrid welding.

[0030] Numbers in the figure: 1-optical fiber, 2-beam splitter, 3-laser galvanometer, 4-workpiece to be welded, 5-high-energy laser, 6-semi-mirror, 7-laser beam one, 8-laser beam two, 9-full-reflecting mirror, 10-motor one, 11-motor two, 12-protective lens, 13-output laser beam one, 14-output laser beam two, 15-welding molten pool, 16-welding gun, 17-shear nail beam, 18-corrugated plate. DETAILED DESCRIPTION

[0031] The present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, in the absence of conflict, the embodiments in this application and the technical features in the embodiments can be combined with each other. It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as those generally understood by those of ordinary skill in the art to which this application belongs. The words "including" or "comprising" and the like used in the disclosure of the present invention mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0032] On the one hand, if Figure 1 As shown, the present invention provides a welding device integrating laser cleaning and laser arc hybrid welding, including a laser (not shown in the figure) connected by an optical fiber 1, a beam splitter 2 and a laser galvanometer 3;

[0033] The laser is used to generate a beam of high-energy laser 5, which is transmitted to the beam splitter 2 through the optical fiber 1 and split into two by the beam splitter 2; the two split laser beams are transmitted to the laser galvanometer 3 through the optical fiber 1 and the laser galvanometer 3 outputs two laser beams with different laser scanning shapes to the workpiece 4 to be welded.

[0034] It should be noted that the laser galvanometer 3 uses an oscillating motor to control the laser reflection path of the reflector using an electrical signal to deflect the light beam. By applying a periodic electrical signal to the electric field, different laser scanning shapes can be output.

[0035] In the above embodiment, the laser galvanometer 3 outputs two laser beams with different laser scanning shapes, one of which is used to laser clean the oxide film, oil stains, impurities, etc. on the weld surface, and the other laser is used in conjunction with the arc to perform laser-arc composite welding on the weld.

[0036] In a specific embodiment, Figure 2As shown, a half-mirror 6 and a total reflection mirror 9 are provided inside the beam splitter 2. A beam of high-energy laser 5 generated by the laser is divided into a laser beam 1 7 and a laser beam 2 8 through the half-mirror 6. The laser beam 1 7 directly enters the optical fiber 1 and is transmitted to the laser galvanometer 3 through the optical fiber 1. The laser beam 2 8 enters the optical fiber 1 through the total reflection mirror 9 and is transmitted to the laser galvanometer 3 through the optical fiber 1.

[0037] In the above embodiment, the laser beam 1 7 and the laser beam 2 8 are used for laser cleaning and laser welding respectively. The adjustment is performed by adjusting the intensity of the reflected light and the intensity of the transmitted light caused by the semi-transparent mirror 6.

[0038] In a specific embodiment, Figure 3 As shown, the semi-transparent mirror 6 includes a laser light-transmitting lens and a metal lattice arranged on the laser light-transmitting lens, and the laser transmittance and laser reflectivity of the semi-transparent mirror are adjusted by adjusting the density of the metal lattice. In this embodiment, by arranging a metal lattice on the laser light-transmitting lens, a part of the laser can be transmitted and a part of the laser can be reflected, and the laser transmittance and laser reflectivity of the semi-transparent mirror can be adjusted by adjusting the density of the metal lattice.

[0039] Optionally, the laser light-transmitting lens is made of quartz, and the metal lattice is made of copper. Optionally, the light intensity ratio of the laser beam 1 to the laser beam 2 is 3:7.

[0040] In a specific embodiment, Figure 4 As shown, the laser galvanometer 3 includes a housing, in which a motor 10 and a motor 2 11 are arranged, and the motor 10 and the motor 2 11 are connected to the total reflection mirror through a transmission rod, and the total reflection mirrors on the two motors are parallel and oppositely arranged up and down. Optionally, a protective lens 12 is also provided at the output end of the laser galvanometer 3.

[0041] In the above embodiment, different electrical signals are input through two motors to control the movement of the transmission rod, thereby controlling the reflection angle of the total reflector. After the laser is incident, it is first irradiated on the total reflector connected to the motor 10, and the mirror surface can be deflected up and down through the transmission rod, thereby realizing the up and down deflection of the light. The mirror surface on the motor 2 11 can be deflected left and right through the transmission rod, thereby realizing the left and right deflection of the light. Therefore, by applying different electrical signals to the two motors, the deflection of the laser beam is controlled, and the desired laser scanning path is output.

[0042] On the other hand, the present invention also provides a welding method integrating laser cleaning and laser arc hybrid welding, and welding is performed using any of the welding devices integrating laser cleaning and laser arc hybrid welding described above.

[0043] In a specific embodiment, Figure 5 As shown, the steel bridge corrugated plate 18 and the shear nail beam 17 are welded using any of the welding devices described above that integrate laser cleaning and laser arc hybrid welding.

[0044] In this embodiment, the laser generated by the laser is finally transmitted to the T-shaped weld formed by the shear nail beam 17 and the corrugated plate 18 through the output laser beam 13 and the output laser beam 2 14 output by the laser galvanometer 3. The output laser beam 13 is irradiated at a position 3 cm in front of the welding molten pool 15, and the output laser beam 2 14 is irradiated at the position of the welding molten pool 15. The welding molten pool 15 is formed by the arc caused by the welding wire in the welding gun 16 and the output laser beam 2 14.

[0045] In the above embodiment, the function of outputting the laser beam 13 is to remove water stains, rust and impurities on the weld surface in front of the weld pool to prevent impurities from entering the weld behind and causing the quality of the weld to deteriorate. The function of outputting the laser beam 2 14 is to increase the heat input of the weld. At the same time, the plasma generated by the laser and the metal can guide the welding arc, increase the weld width, and realize the welding of large gap welds.

[0046] The mechanism of laser cleaning by outputting laser beam 13 is as follows Figure 6 As shown, the output laser beam 13 irradiates impurities such as oxide film on the surface of the welding material, and the oxide film and other impurities are partially decomposed into plasma and metal vapor. Part of the impurity fragments are peeled off the metal surface under the action of plasma and vapor, thereby achieving the effect of surface cleaning.

[0047] Laser arc hybrid welding mechanism Figure 7 As shown, the output laser beam 2 14 directly irradiates the surface of the metal to be welded based on the removal of the oxide film by the output laser beam 13, so that plasma is also formed on the metal surface. The welding arc forms a path with the welding material under the induction of the plasma, thereby realizing the welding of the materials.

[0048] In a specific embodiment, when welding, the laser scanning frequency is 50-150Hz, the diameter of a single circle is 10-20mm, the laser power is 1000-2000W, the arc current is 200-350A, the voltage is 20-35V, and the welding speed is 4-10mm / s. Optionally, the laser scanning frequency is 100Hz, the diameter of a single circle is 15mm, the laser power is 1500W, the arc current is 280A, the voltage is 28V, and the welding speed is 5mm / s.

[0049] In a specific embodiment, a joint without laser cleaning and laser welding is welded with a joint with laser cleaning and laser arc hybrid welding according to the present invention. The morphology and tensile strength of the T-shaped weld joints are as follows: Figure 8-10 As shown. Figure 8-10 It can be seen that without cleaning and laser treatment, the weld is not fully formed and has defects such as inclusions and cracks. This defect will lead to low joint strength of 419MPa and greatly reduce the fatigue strength of the joint. The bridge is a dynamic load-bearing structure with high requirements for fatigue performance. Figure 8 The weld shown cannot meet the bridge use standards, resulting in bridge safety hazards. However, the weld joints that have been cleaned with laser and laser arc hybrid welding have full joint formation, no defects such as inclusions, pores, and cracks in the weld structure, and the tensile strength of the joint is increased to 431MPa. At the same time, since there are no defects inside the weld, the fatigue performance of the weld is greatly improved, meeting the use requirements of the bridge.

[0050] In summary, the present invention integrates laser cleaning and welding into one, realizes the simultaneous cleaning and welding, ensures the welding forming and the quality of the weld, and through laser-arc hybrid welding, the arc is guided by the laser, the welding molten width is increased, and the one-time welding of large gap welds is realized; in addition, in terms of economic benefits, the present invention no longer needs to use manpower or equipment to clean and polish the weld surface, which not only saves labor costs and material costs, but also improves production efficiency; no additional laser is needed for laser cleaning, which saves equipment costs. Compared with the prior art, the present invention has significant progress.

[0051] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A welding device integrating laser cleaning and laser arc hybrid welding, characterized in that: It includes a laser, a beam splitter and a laser galvanometer connected by optical fiber; The laser is used to generate a beam of high-energy laser light, which is transmitted to the beam splitter through the optical fiber and split into two by the beam splitter; The two split laser beams are transmitted to the laser galvanometer through the optical fiber, and the laser galvanometer outputs two laser beams with different laser scanning shapes to the workpiece to be welded.

2. The welding device integrating laser cleaning and laser arc hybrid welding according to claim 1 is characterized in that: A half-mirror and a total reflection mirror are arranged inside the beam splitter. A beam of high-energy laser generated by the laser is divided into laser beam 1 and laser beam 2 through the half-mirror. Laser beam 1 directly enters the optical fiber and is transmitted to the laser galvanometer through the optical fiber. Laser beam 2 enters the optical fiber through the total reflection mirror and is transmitted to the laser galvanometer through the optical fiber.

3. The welding device integrating laser cleaning and laser arc hybrid welding according to claim 2 is characterized in that: The semi-mirror comprises a laser-transmitting lens and a metal dot matrix arranged on the laser-transmitting lens. The laser transmittance and laser reflectance of the semi-mirror are adjusted by adjusting the density of the metal dot matrix.

4. The welding device integrating laser cleaning and laser arc hybrid welding according to claim 3 is characterized in that: The laser light-transmitting lens is made of quartz, and the metal dot matrix is ​​made of copper.

5. The welding device integrating laser cleaning and laser arc hybrid welding according to any one of claims 2 to 4, characterized in that: The light intensity ratio of the laser beam 1 to the laser beam 2 is 3:

7.

6. The welding device integrating laser cleaning and laser arc hybrid welding according to claim 1 is characterized in that: The laser galvanometer comprises a shell, in which a motor 1 and a motor 2 are arranged, and the motor 1 and the motor 2 are both connected to a total reflective mirror through a transmission rod, and the total reflective mirrors on the two motors are vertically parallel and relatively arranged.

7. The welding device integrating laser cleaning and laser arc hybrid welding according to claim 6 is characterized in that: The output end of the laser galvanometer is also provided with a protective lens.

8. A welding method integrating laser cleaning and laser arc hybrid welding, characterized in that: Welding is performed using the welding device integrating laser cleaning and laser arc hybrid welding as described in any one of claims 1 to 7.

9. The welding method integrating laser cleaning and laser arc hybrid welding according to claim 8, characterized in that: The corrugated plate and the shear nail beam of the steel bridge are welded by using the welding device integrating laser cleaning and laser arc hybrid welding as described in any one of claims 1 to 7.

10. The welding method integrating laser cleaning and laser arc hybrid welding according to claim 9, characterized in that: When welding, the laser scanning frequency is 50-150Hz, the diameter of a single circle is 10-20mm, the laser power is 1000-2000W, the arc current is 200-350A, the voltage is 20-35V, and the welding speed is 4-10mm / s.

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