Laser-TIG arc hybrid welding device and method for curved welds

Abstract

The present invention relates to a laser-TIG arc hybrid welding device and method for curved welds. The hybrid welding device comprises: a laser welding processing head and an arc welding gun, wherein the laser beam output by the laser welding processing head and the TIG arc output by the arc welding gun act on the same molten pool, and the arc welding gun can rotate around the linear direction of the laser beam as an axis. The laser arc hybrid welding method comprises the steps of manipulator teaching, welding trajectory compensation correction, motion control programming, laser arc synchronous motion welding and the like. The embodiments of the present invention avoid the problems of poor fusion defects and / or undercut defects, are suitable for the curved weld welding process, and are beneficial to improving the welding quality of the curved weld.

Description

Technical Field

[0001] The invention relates to the technical field of material welding, and in particular to a laser-TIG arc hybrid welding device and method for curved welds. Background Art

[0002] Laser arc hybrid welding combines two heat sources with completely different physical properties and energy transmission mechanisms and acts on the same processing position at the same time, which not only fully utilizes the advantages of the two heat sources, but also makes up for their respective shortcomings, thus forming a new and efficient heat source welding method. Among them, laser and arc paraxial hybrid is the most widely used and mature, and the commonly used composite arcs include MIG arc and TIG arc.

[0003] In the laser arc hybrid welding process, the laser and arc heat sources are often arranged one in front of the other, and the central axis of the light arc is basically tangent to the welding trajectory. Due to the additional effect of the arc heat source, the front molten pool width is much wider than that of self-melting laser welding. When deep penetration welding of thin-walled metal materials is achieved, the front molten pool width is much larger than the back molten pool width, so the cross-section of the composite weld is mostly wide at the top and narrow at the bottom. Under the influence of the laser welding hole and the arc column, the composite welding molten pool is accompanied by a violent heat and mass transfer process. When welding a curved weld, in addition to the original thermal effect in the molten pool, the molten pool will also be affected by centrifugal force. Since there is relatively more liquid metal at the top of the molten pool, the centrifugal force on the liquid metal in this part is relatively large. When the radius of curvature of the curved weld is large, the centrifugal force drives the liquid metal to flow outward. At this time, the surface tension of the liquid metal will offset the influence of the centrifugal force, so that the molten pool tends to maintain a relatively balanced state with a basic central symmetry. When the radius of curvature of a curved weld is less than a certain threshold, the centrifugal force of the liquid metal at the top of the local molten pool may be greater than the surface tension of that portion, and the liquid metal at that portion will tend to flow toward the outside, causing the front face of the weld generated by the solidification of the molten pool to easily generate undercut defects at the weld toe portion close to the inner side of the curve, while the front face of the weld toe portion far from the inner side of the curve is prone to poor fusion defects.

[0004] Poor fusion defects or undercut defects at the weld toe on the front side of the weld will have a certain weakening effect on the mechanical properties of the welded joint, especially the fatigue properties of the welded joint, so the above welding defects should be avoided as much as possible. At present, although the above welding defects can be eliminated by post-welding laser modification welding or repair welding, laser modification welding or repair welding are remedial measures, which not only affect the normal progress of welding operations and lead to low welding production efficiency, but also cause secondary heating to the welded joint, which can easily lead to coarsening of the grains and microstructures of the welded joints and reduction of mechanical properties. If the geometric action positions of the two heat sources of laser and arc are adjusted, the stress state of the liquid metal at the top of the molten pool is changed to affect the flow of the liquid metal in the molten pool, and the welding defects at the weld toe on the front side of the weld are eliminated without post-welding remedial measures, which is the best way to significantly improve the efficiency of welding operations.

[0005] In view of this, the present application proposes a laser-TIG arc hybrid welding device and method for curved welds. Summary of the invention

[0006] (1) Technical issues to be solved

[0007] The first aspect of the embodiment of the present invention proposes a laser-TIG arc hybrid welding device and method for curved welds, the device comprising: a laser welding processing head and an arc welding gun, the laser beam output by the laser welding processing head and the TIG arc output by the arc welding gun act on the same molten pool, and the arc welding gun can rotate around the linear direction of the laser beam as an axis. The embodiment of the present invention avoids the problem of poor fusion defects and / or undercut defects, is suitable for the curved weld welding process, and is conducive to improving the welding quality of the curved weld.

[0008] The second aspect of the embodiment of the present invention provides a laser-TIG arc hybrid welding device for curved welds, including the steps of manipulator teaching, welding trajectory compensation correction, motion control programming, laser arc synchronous motion welding, etc. The embodiment of the present invention is applicable to the curved weld welding process, which is conducive to improving the welding quality of the curved weld.

[0009] (2) Technical solution

[0010] A first aspect of an embodiment of the present invention provides a laser-TIG arc hybrid welding device for curved welds, the device comprising:

[0011] A laser welding processing head, used for outputting a laser beam for welding;

[0012] The arc welding gun is a TIG welding gun, which is used to output a TIG arc for welding;

[0013] The laser beam output by the laser welding processing head and the TIG arc output by the arc welding gun act on the same molten pool, and the arc welding gun can rotate around the linear direction of the laser beam as an axis.

[0014] Furthermore, the laser-TIG arc hybrid welding device also includes:

[0015] A connecting seat, on which the laser welding processing head is arranged;

[0016] A clamping assembly, the clamping assembly being rotatably connected to the connecting seat, the clamping assembly being used to clamp the arc welding gun and keep the arc welding gun in a preset tilted state;

[0017] The driving assembly is used to drive the clamping assembly and the arc welding gun to rotate or position around the straight line direction where the laser beam is located.

[0018] Furthermore, the connecting seat includes: a vertical plate, a horizontal plate and a sleeve, the vertical plate is perpendicular to the horizontal plate and is installed on the side of the laser welding processing head, the side of the laser welding processing head outputting the laser beam is arranged on the horizontal plate, and the middle of the sleeve is a through hole for transmitting the laser beam; the central axis of the sleeve coincides with the straight line where the laser beam is located.

[0019] Furthermore, the clamping assembly includes a rotating sleeve and a clamping arm, the rotating sleeve is arranged on the outer peripheral wall of the sleeve, and a bearing is arranged between the rotating sleeve and the sleeve, the middle part of the clamping arm is fixed to the periphery of the rotating sleeve, one end of the clamping arm clamps and fixes the TIG welding gun, and the other end of the supporting arm clamps and fixes the wire guide nozzle, the TIG welding gun and the wire guide nozzle are arranged on the front and rear sides of the laser beam, and the welding wire is fed into the front edge of the welding hole through the wire guide nozzle.

[0020] Furthermore, the driving assembly comprises a rotary motor, and the rotary motor is used to drive the rotating sleeve to rotate or position around the linear direction of the laser beam as the rotation axis.

[0021] Furthermore, an annular boss is provided at one end of the outer circumferential wall of the sleeve, an external thread is provided at the other end of the outer circumferential wall of the sleeve, the rotating sleeve is arranged between the annular boss and the external thread, and the external thread is threadedly connected with a threaded retaining ring.

[0022] Furthermore, the driving assembly also includes a first gear, and a second gear is provided on the outer peripheral wall of the rotating sleeve, and the first gear and the second gear are meshed with each other for transmission.

[0023] Furthermore, the rotating motor is fixed on the connecting seat, and the driving shaft of the rotating motor is parallel to the rotating axis of the rotating sleeve.

[0024] A second aspect of an embodiment of the present invention provides a laser-TIG arc hybrid welding method for a curved weld, which is applied to the laser-TIG arc hybrid welding device for a curved weld described in any one of the first aspects of the embodiment of the present invention. The welding method comprises the following steps:

[0025] Robot teaching: A robot is used to drive the laser-TIG arc hybrid welding device to realize pre-welding teaching of curved welds. During the teaching process, the robot controls the laser beam to move along the welding trajectory;

[0026] Welding trajectory compensation correction: based on the robot teaching motion trajectory of the laser beam, the optimal geometric position state of the laser welding processing head and the arc welding gun at each teaching point is calculated;

[0027] Motion control programming: by controlling the rotation angle of the arc welding gun to change the geometric position state of the arc welding gun, the motion control programming after welding trajectory compensation correction is completed;

[0028] Laser arc synchronous motion welding: according to the determined hybrid welding parameters, confirm the laser arc geometric position state, welding speed, laser power, welding current and other welding parameters, and implement the laser-TIG arc hybrid welding of the curved weld according to the preset motion control programming program until the welding is completed;

[0029] Welding quality inspection: Use non-destructive testing methods to inspect the welding quality. When the quality inspection fails, the defects that exceed the standard should be repaired, and the welding parts after repair welding should be re-inspected until they pass the inspection.

[0030] Furthermore, the method for calculating the optimal geometric position state of the laser welding processing head and the arc welding gun at each teaching point comprises the following steps:

[0031] Calculating the magnitude and direction of the force applied by the laser welding processing head and the arc welding gun;

[0032] Calculate the centrifugal force of the liquid metal in the molten pool;

[0033] The angle of the arc welding gun is adjusted to keep the forces applied by the laser welding processing head and the arc welding gun, the surface tension of the liquid metal in the molten pool, the welding wire thrust and the centrifugal force of the liquid metal in the molten pool balanced.

[0034] (3) Beneficial effects

[0035] The embodiment of the present invention realizes the arc column area and welding wire of the side-axis TIG arc welding by rotating the motor and the gear meshing transmission, and the arc column area and welding wire are arranged on both sides of the laser beam. The arc welding gun rotates around the linear direction of the laser beam as the axis, ensuring that the combined force of the laser welding processing head and the arc welding gun, the surface tension of the liquid metal in the molten pool, the thrust of the welding wire, and the centrifugal force of the liquid metal in the molten pool are balanced, so that the liquid metal in the molten pool maintains a more stable relative equilibrium state, further alleviating the tendency of the liquid metal in the molten pool to excessively deviate to one side, thereby avoiding the problem of poor fusion defects and / or undercut defects; the laser-TIG arc hybrid welding device of the embodiment of the present invention is suitable for the curved weld welding process, which is beneficial to improving the welding quality of the curved weld.

[0036] The laser-TIG arc hybrid welding method of the embodiment of the present invention can automatically adjust the optimal geometric position state of the laser welding processing head and the arc welding gun, ensuring that the centrifugal force of the liquid metal in the molten pool maintains a more stable relative equilibrium state, further alleviating the tendency of the liquid metal in the molten pool to excessively deviate to one side, thereby avoiding the problem of poor fusion defects and / or undercut defects.

[0037] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments of the present invention are 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 creative work.

[0039] Figure 1 It is a schematic diagram of conventional curved weld welding in the prior art.

[0040] Figure 2 It is a top view of a conventional curved weld in the prior art.

[0041] Figure 3 It is a schematic diagram of the position of laser-TIG arc hybrid welding according to an embodiment of the present invention.

[0042] Figure 4 It is a schematic diagram of a top view of laser-TIG arc hybrid welding according to an embodiment of the present invention.

[0043] Figure 5 It is a schematic structural diagram of a laser-TIG arc hybrid welding device according to an embodiment of the present invention.

[0044] Figure 6It is a schematic structural diagram of a connecting sleeve according to an embodiment of the present invention.

[0045] Figure 7 It is a flow chart of a laser-TIG arc hybrid welding method according to an embodiment of the present invention.

[0046] Figure 8 It is a schematic diagram of the forces acting on liquid metal in a molten pool according to an embodiment of the present invention.

[0047] In the figure: 1-laser beam; 2-arc welding gun; 3-welding track; 4-solidified metal; 5-poor fusion defect; 6-bite defect; 7-welding keyhole; 8-arc action area; 9-molten pool; 10-arc center axis plane; 11-tangent line; 12-laser welding processing head; 121-focusing lens; 122-anti-splash lens; 13-connecting seat; 131-vertical plate; 132-horizontal plate; 133-sleeve; 1331-through hole; 1332-annular boss; 1333-external thread; 14-rotating motor; 141-first gear; 15-first tapered roller bearing; 16-rotating sleeve; 161-second gear; 17-second tapered roller bearing; 18-threaded retaining ring; 19-clamping arm; 20-TIG welding gun; 21-wire guide nozzle; 22-welding wire; 23-parent material; 24-horizontal blowing air curtain. DETAILED DESCRIPTION

[0048] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to exemplarily illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention, that is, the present invention is not limited to the described embodiments, and covers any modification, replacement and improvement of parts, components and connection modes without departing from the spirit of the present invention.

[0049] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0050] The following will refer to the attached Figure 1 -Attached Figure 8 The present application is described in detail with reference to embodiments.

[0051] According to a first aspect of an embodiment of the present invention, a laser-TIG arc hybrid welding device for a curved weld includes:

[0052] A laser welding processing head 12, used for outputting a laser beam 1 for welding;

[0053] The arc welding gun 2 is a TIG welding gun, which is used to output a TIG arc for welding;

[0054] The laser beam 1 output by the laser welding processing head 12 and the TIG arc output by the arc welding gun 2 act on the same molten pool, and the arc welding gun 2 can rotate around the linear direction of the laser beam 1 as an axis.

[0055] See the attached Figure 3-5 And attached Figure 8 To illustrate the embodiment of the present invention, as described in the background technology, when welding a curved weld, the molten pool 9 is acted upon by centrifugal force. When the radius of curvature of the curved weld is less than a certain threshold value, the centrifugal force of the liquid metal at the top of the local molten pool 9 may be greater than the surface tension of the portion, and the liquid metal at the portion will tend to flow to the side of the solidified metal 4 on the outside, resulting in the front face of the weld generated by the solidification of the molten pool 9 being prone to generating an undercut defect 6 at the weld toe portion close to the inner side of the curve, and the front face of the weld being prone to generating a poor fusion defect 5 at the weld toe portion away from the inner side of the curve. Based on this, the laser-TIG arc hybrid welding device for a curved weld of the embodiment of the present invention comprises: a laser welding processing head 12 and an arc welding gun 2 (TIG welding gun 20), wherein the laser beam 1 output by the laser welding processing head 12 and the arc output by the TIG welding gun 20 act on the same molten pool, and the curved weld can be conveniently welded by the laser-TIG arc hybrid welding method of the laser welding processing head 12 and the TIG welding gun 20.

[0056] In order to balance the centrifugal force of the liquid metal generated during the welding process and prevent the liquid metal from flowing out of the molten pool 9 to generate poor fusion defects 5 and / or undercut defects 6, the TIG welding gun 20 of the embodiment of the present invention can be rotated around the linear direction of the laser beam 1 as an axis, so that the TIG welding gun 20 can be rotated to adjust the direction of the magnetic blowing force of the arc output by the TIG welding gun 20. Figure 8 As shown, the combined force F2 of the laser welding processing head 12 and the TIG welding gun 20, the surface tension F3 of the liquid metal in the molten pool 9, the welding wire thrust F4 generated during the transition of the welding wire droplet to the molten pool through the short-circuit transition mode under the action of the surface tension, and the centrifugal force F1 of the liquid metal in the molten pool 9 are balanced. Specifically, in the attached Figure 8 In the figure, the combined force F2 of the laser welding processing head 12 and the TIG welding gun 20 is decomposed according to the force, and the component force in the opposite direction to the centrifugal force F1 is F 2x ; The component of the wire thrust F4 in the same direction as the centrifugal force F1 is F 4x ; When keeping F 2x +F3=F1+F 4x When the centrifugal force F1 is applied, the liquid metal in the molten pool 9 will remain in balance and will not generate poor fusion defects 5 and / or undercut defects 6.

[0057] To sum up, in the embodiment of the present invention, the arc welding gun 2 (TIG welding gun 20) is rotated around the straight line direction of the laser beam 1 as the axis to ensure that the combined force F2 of the laser welding processing head 12 and the TIG welding gun 20, the surface tension F3 of the liquid metal in the molten pool 9, the welding wire thrust F4 generated in the process of the welding wire droplet transitioning to the molten pool through a short-circuit transition under the action of the surface tension, and the centrifugal force F1 of the liquid metal in the molten pool 9 are balanced, so that the liquid metal in the molten pool 9 maintains a more stable relative equilibrium state, further alleviating the tendency of the liquid metal in the molten pool to excessively deviate to one side, thereby avoiding the problem of poor fusion defects 5 and / or undercut defects 6; the laser-TIG arc hybrid welding device of the embodiment of the present invention is suitable for the curved weld welding process, which is beneficial to improving the welding quality of the curved weld.

[0058] For further information, see Appendix Figure 5 As shown, according to one embodiment of the present invention, the laser-TIG arc hybrid welding device further includes: a connection seat 13, a clamping assembly and a driving assembly (the clamping assembly and the driving assembly are not shown in the figure). Specifically, the laser welding processing head 12 is arranged on the connection seat 13; the clamping assembly is rotatably connected to the connection seat 13, and the clamping assembly is used to clamp the TIG welding gun 20 and keep the TIG welding gun 20 in a preset tilted state; the driving assembly is used to drive the clamping assembly and the TIG welding gun 20 to rotate or position around the straight line direction of the laser beam 1.

[0059] The following is combined with Figure 5 To illustrate an embodiment of the present invention, in the embodiment of the present invention, a laser welding processing head 12 is disposed on a connecting seat 13, and a laser beam 1 passes through the laser welding processing head 12 via a focusing lens 121 and irradiates toward the part to be welded. At the same time, the clamping assembly in the embodiment of the present invention can be rotatably connected to the connecting seat 13, and the clamping assembly is used to clamp the TIG and keep the TIG welding gun 20 in a preset tilted state, so that the laser welding processing head 12 and the TIG welding gun 20 can be staggered in spatial position without causing interference; at the same time, the laser beam 1 output by the laser welding processing head 12 and the arc magnetic force output by the TIG welding gun 20 can act on the same molten pool 9 from different directions (for example, one in front and one behind) to perform laser-TIG arc composite welding. Finally, the driving assembly of the embodiment of the present invention is used to drive the clamping assembly and the TIG welding gun 20 around the linear direction of the laser beam 1 (that is, the attached Figure 5The vertical direction in the molten pool 9 can be rotated or positioned, so in the actual welding process, the angle of the output arc magnetic force of the TIG welding gun 20 can be changed according to the size and direction of the centrifugal force F1 of the liquid metal in the molten pool 9, ensuring that the combined force F2 of the laser welding processing head 12 and the TIG welding gun 20, the surface tension F3 of the liquid metal in the molten pool 9, the welding wire thrust F4 generated in the process of the welding wire droplet transitioning to the molten pool through a short-circuit transition under the action of the surface tension, and the centrifugal force F1 of the liquid metal in the molten pool 9 are balanced, so that the liquid metal in the molten pool 9 maintains a more stable relative equilibrium state, further alleviating the tendency of the liquid metal in the molten pool to excessively deviate to one side, thereby avoiding the problems of poor fusion defects 5 and / or undercut defects 6.

[0060] Specifically, in one embodiment of the present invention, refer to the attached Figure 5 As shown, the center axis of the TIG welding gun 20 and the welding wire fed is in the normal direction of the welding surface (see Figure 5 The inclination angle of the welding wire 22 is 30°-60°. The specific inclination angle can be selected according to the actual needs of welding and is not limited here. The vertical distance between the tungsten tip and the workpiece surface is 1.5mm-5mm, and the horizontal distance between the tungsten tip and the center of the laser beam 1 is 3mm-5mm. The dry extension of the welding wire 22 is not more than 12mm, and the preset value of the light wire spacing is 0.5mm-2mm; the diameter of the welding wire can be selected within the range of 0.8mm-1.6mm.

[0061] For further information, see Appendix Figure 5 and 6 As shown, according to another embodiment of the present invention, the connecting seat 13 includes: a vertical plate 131, a horizontal plate 132 and a sleeve 133, the vertical plate 131 is connected to the horizontal plate 132, the vertical plate 131 is perpendicular to the horizontal plate 132 and is installed on the side of the laser welding processing head, the side of the laser welding processing head 12 outputting the laser beam 1 is arranged on the horizontal plate 132, the middle of the sleeve 133 is a through hole 1331 for transmitting the laser beam 1; the central axis of the sleeve 133 coincides with the straight line where the laser beam 1 is located. In the embodiment of the present invention, on the one hand, a connecting seat 13 is provided to fix the laser welding processing head 12, so that the laser welding processing head 12 can be firmly fixed on the horizontal plate 132 of the connecting seat 13, and the laser beam 1 output by the laser welding processing head 12 can be stably and accurately irradiated on the molten pool 9, forming laser-TIG arc hybrid welding together with the TIG welding gun 20; on the other hand, the setting of the sleeve 133 can form relative rotation with the clamping assembly together with the clamping assembly, and can support the clamping assembly, so that the laser-TIG arc hybrid welding device of the embodiment of the present invention forms a complete structure (the specific structure of the clamping assembly and the specific connection method with the sleeve 133 are disclosed in detail below).

[0062] Further, according to one embodiment of the present invention, referring to the attached Figure 5 As shown, the driving assembly includes a driving device (which may be a rotating motor 14), so that the rotation or stop of the rotating motor 14 can be easily controlled by power excitation, and the rotating motor 14 is used to drive the rotating sleeve 16 to rotate or position around the linear direction of the laser beam 1 as the rotating axis. The rotating motor 14 is fixedly connected to the vertical plate 131, thereby achieving the fixing of the rotating motor 14, so that the rotating motor 14 and the connecting seat 13 remain relatively stationary during the actual driving process.

[0063] Further, the driving device 14 is fixed on the connecting seat 13, and the driving shaft of the driving device 14 is parallel to the rotating shaft of the rotating sleeve 16. Specifically, as mentioned above, the driving device 14 is fixed on the vertical plate 131 of the connecting seat 13, and the vertical plate 131 is vertically connected to the horizontal plate 132, and the driving shaft of the driving device 14 is parallel to the rotating shaft of the rotating sleeve 16, so that the rotation direction of the driving device 14 can be ensured to be the same as the rotation direction of the rotating sleeve 16, and then it is convenient to set the position of the driving device 14 according to the rotation direction of the rotating sleeve 16, so that the rotation of the rotating sleeve 16 drives the arc welding gun 2 to rotate around the linear direction of the laser beam 1 as the axis.

[0064] As mentioned above, in the embodiment of the present invention, the rotating sleeve 16 and the sleeve 133 can rotate relative to each other, and then the rotating sleeve 16 drives the arc welding gun 2 to rotate through the clamping arm 19, so as to achieve the purpose of rotating the arc welding gun 2 around the linear direction of the laser beam 1 as the axis. Based on this, the embodiment of the present invention applies a force to the rotating sleeve 16 to rotate or position around the linear direction of the laser beam 1 as the rotation axis through the rotating motor 14 provided, thereby automatically achieving the relative rotation of the rotating sleeve 16 and the sleeve 133.

[0065] For further information, see Appendix Figure 5 and 6As shown, according to another embodiment of the present invention, the clamping assembly includes a rotating sleeve 16 and a clamping arm 19, the rotating sleeve 16 is sleeved on the outer peripheral wall of the sleeve 133, and a bearing is arranged between the rotating sleeve 16 and the sleeve 133, one end of the rotating sleeve 16 is designed as a second gear 161, and the second gear 161 is meshed and matched with the first gear 141. The rotating sleeve 16 is a hollow structure, sleeved on the middle part of the outer side of the sleeve 133 and fixed to the middle part of the sleeve 133 by the first tapered roller bearing 15 and the second tapered roller bearing 17. At the external thread 1333 of the sleeve 133, the second tapered roller bearing 17 is fixed by a threaded retaining ring 18 matching the thread of the external thread 1333, so as to realize the axial assembly and fixation of the rotating sleeve 16 sleeved on the sleeve 133. The middle part of the clamping arm 19 is fixed to the periphery of the rotating sleeve 16, one end of the clamping arm 19 clamps and fixes the TIG welding gun 20, and the other end of the clamping arm 19 clamps and fixes the wire guide nozzle 21. The welding wire 22 is fed to the front edge of the welding keyhole 7 through the wire guide nozzle 21. The TIG welding gun 20 and the wire guide nozzle 21 are arranged at the front and rear sides of the laser beam 1.

[0066] Specifically, in one embodiment of the present invention, refer to the attached Figure 5 As shown, a first tapered roller bearing 15 and a second tapered roller bearing 17 may be arranged between the rotating sleeve 16 and the sleeve 133. The inner rings of the first tapered roller bearing 15 and the second tapered roller bearing 17 are sleeved on the outer circumferential wall of the sleeve 133, and the outer rings of the first tapered roller bearing 15 and the second tapered roller bearing 17 are sleeved on the inner wall of the rotating sleeve 16. The first tapered roller bearing 15 and the second tapered roller bearing 17 are used to realize relative rotation between the rotating sleeve 16 and the sleeve 133.

[0067] Further, according to another embodiment of the present invention, referring to the attached Figure 5 and attached Figure 6 As shown, an annular boss 1332 is provided at one end of the outer circumferential wall of the sleeve 133, and an external thread 1333 is provided at the other end of the outer circumferential wall of the sleeve 133. The rotating sleeve 16 is sleeved between the annular boss 1332 and the external thread 1333, and the external thread 1333 is threadedly connected with a threaded retaining ring 18. The setting of the annular boss 1332 can limit the rotating sleeve 16 from one side; the cooperation of the external thread 1333 and the threaded retaining ring 18 can limit the rotating sleeve 16 from the other end, so that the rotating sleeve 16 is fixed on the sleeve 133, and is not prone to relative sliding. It is easy to control the position of the rotating sleeve 16, thereby ensuring that the position of the arc welding gun 2 is not prone to relative movement. Specifically, refer to the attached Figure 5 and attached Figure 6 As shown, the annular boss 1332 is arranged on a side close to the transverse plate 132 ; correspondingly, the external thread 1333 is arranged on a side away from the transverse plate 132 .

[0068] Further, according to another embodiment of the present invention, referring to the attached Figure 5 As shown, the driving assembly further includes a first gear 141, and a second gear 161 is disposed on the outer peripheral wall of the rotating sleeve 16, and the first gear 141 and the second gear 161 are meshed with each other for transmission. The meshing transmission between the first gear 141 and the second gear 161 can accurately transmit the driving force of the rotating motor 14 to the rotating sleeve 16. In addition, the rotating motor 14 can also drive the rotating sleeve 16 to rotate in other ways, such as using a belt, a rotating shaft to directly drive, etc., which will not be described one by one here.

[0069] Specifically, in an embodiment of the present invention, the transmission ratio range of the first gear 141 and the second gear 161 is 1-10. For example, the transmission ratio of the first gear 141 and the second gear 161 is 1. The transmission ratio of the first gear 141 and the second gear 161 can also be 10, and so on. They are not repeated here one by one.

[0070] Furthermore, to protect the laser welding processing head 12, an anti-splash lens 122 is provided between the laser welding processing head 12 and the sleeve 133. At the same time, to minimize the contamination of the anti-splash lens 122 by welding spatter, a horizontal blowing air curtain 24 is also provided at the lower end of the sleeve 13. The inflation pressure of the horizontal blowing air curtain 24 during welding should not be lower than 0.3 MPa. The horizontal blowing air curtain 24 can suppress the spatter debris generated by welding and prevent the debris from contaminating the anti-splash lens 122.

[0071] Furthermore, the laser beam 1 may include a non-scanning laser beam and a scanning laser beam, the type of the laser beam 1 may include a fiber laser and a YAG laser, the focal length of the laser beam 1 may be between 150 mm and 500 mm, and the focal spot diameter of the laser beam 1 may be between When a scanning laser beam is used, the scanning frequency of the laser beam 1 can be adjusted between 30-300 Hz, and the scanning amplitude can be adjusted between Of course, the specific working parameters can be set as needed and will not be described in detail here.

[0072] A laser-TIG arc hybrid welding method for a curved weld according to an embodiment of the second aspect of the present invention is applied to an embodiment of a laser-TIG arc hybrid welding device for a curved weld according to any one of the first aspects of the present invention, see the attached Figure 7 As shown, the laser-TIG arc hybrid welding method includes the following steps:

[0073] S120, robot teaching: the robot is used to drive the laser-TIG arc hybrid welding device to realize the pre-welding teaching of the curved weld. During the teaching process, the robot controls the laser beam 1 along the attached Figure 3The welding trajectory 3 shown moves;

[0074] S130, welding trajectory compensation correction: based on the robot teaching motion trajectory of the laser beam 1, calculate the optimal geometric position state of the laser welding processing head 12 and the arc welding gun 2 at each teaching point; that is, as shown in the attached Figure 4 As shown, the arc mid-axis plane 10 at each teaching point and the tangent line 11 of the welding track 3 at the laser action point maintain an included angle α.

[0075] S140, motion control programming: changing the geometric position state of the arc welding gun 2 by controlling the rotation angle of the arc welding gun 2, and completing the motion control programming after welding trajectory compensation correction;

[0076] S150, laser arc synchronous motion welding: according to the determined composite welding parameters, confirm the laser arc geometric position state, welding speed, laser power, welding current and other welding parameters, and implement the laser-TIG arc composite welding of the curved weld according to the preset motion control programming program until the welding is completed.

[0077] The laser-TIG arc hybrid welding method of the embodiment of the present invention realizes the revolution function of the laser-TIG arc hybrid welding with the help of a manipulator, and cooperates with its own rotation function to make the tangent of the laser-TIG arc hybrid welding plane and the welding trajectory 3 of the curved weld maintain a preset angle α, and the preset angle changes with the change of the curvature radius of the curved weld. By changing the stress state of the liquid metal at the top of the molten pool 9, the flow of the liquid metal in the molten pool 9 is affected, which is particularly conducive to eliminating the poor fusion defect 5 or the undercut defect 6 at the front weld toe of the weld that is easy to occur when the curvature radius of the curved weld is small, and is more conducive to improving the quality of laser-TIG arc hybrid welding.

[0078] At the same time, relying on the robot teaching, during the teaching process, the robot controls the laser beam 1 along the Figure 3 The welding trajectory 3 shown in the figure moves, and then, based on the robot teaching motion trajectory of the laser beam 1, the optimal geometric position state of the laser welding processing head 12 and the arc welding gun 2 at each teaching point is calculated; the geometric position state of the arc welding gun 2 is changed by controlling the rotation angle of the arc welding gun 2, and the motion control programming after the welding trajectory compensation correction is completed; and then the direction of the applied force of the arc welding gun 2 at each welding point can be automatically calculated, thereby ensuring that the liquid metal of the molten pool 9 at each welding point can maintain a more stable relative dynamic equilibrium state.

[0079] Further, according to another embodiment of the present invention, the method for calculating the optimal geometric position state of the laser welding processing head 12 and the arc welding gun 2 at each teaching point comprises the following steps:

[0080] Calculate the magnitude and direction of the force acting on the laser welding processing head 12 and the arc welding gun 2;

[0081] Calculate the centrifugal force of the molten pool;

[0082] The angle of the arc welding gun 2 is adjusted so that the forces applied by the laser welding processing head 12 and the arc welding gun 2, the surface tension of the liquid metal in the molten pool 9, and the welding wire thrust generated during the transition of the welding wire droplet to the molten pool through a short-circuit transition under the action of the surface tension are balanced with the centrifugal force of the liquid metal in the molten pool 9.

[0083] As mentioned above and in conjunction with the attached Figure 8 To illustrate an embodiment of the present invention, in order to balance the centrifugal force of the liquid metal generated during the welding process and prevent the liquid metal from flowing out of the molten pool 9 to generate poor fusion defects 5 and / or undercut defects 6, the arc welding gun 2 of the embodiment of the present invention can rotate around the linear direction of the laser beam 1 as the axis, so that the arc welding gun 2 can be rotated to adjust the direction of the magnetic blowing force of the arc output by the arc welding gun 2. In the embodiment of the present invention, the magnitude and direction of the force applied by the laser welding processing head 12 and the arc welding gun 2 are first calculated, and the centrifugal force of the molten pool is calculated (as mentioned above, it can be calculated by manipulator teaching and computer); finally, according to the calculation result, the angle of the arc welding gun 2 is adjusted to make the force applied by the laser welding processing head 12 and the arc welding gun 2, the surface tension of the liquid metal in the molten pool 9, and the welding wire thrust generated in the process of the welding wire droplet transitioning to the molten pool through a short-circuit transition method under the action of the surface tension and the centrifugal force of the liquid metal in the molten pool 9 remain balanced. In the attached Figure 8 In the figure, the combined force F2 of the laser welding processing head 12 and the arc welding gun 2 is decomposed according to the force, and the component force in the opposite direction to the centrifugal force F1 is F 2x ; The component of the wire thrust F4 in the same direction as the centrifugal force F1 is F 4x ; When keeping F 2x +F3=F1+F 4x When the centrifugal force F1 is applied, the liquid metal in the molten pool 9 will remain in balance and will not generate poor fusion defects 5 and / or undercut defects 6.

[0084] To sum up, the embodiment of the present invention can automatically adjust the optimal geometric position of the laser welding processing head 12 and the arc welding gun 2, ensuring that the liquid metal in the molten pool 9 maintains a more stable relative equilibrium state, further alleviating the tendency of the liquid metal in the molten pool to excessively deviate to one side, thereby avoiding the problem of poor fusion defects 5 and / or undercut defects 6.

[0085] For further information, see Appendix Figure 7As shown, the embodiment of the present invention further includes step S110, parts cleaning and assembly before the robot teaching, and the parts cleaning and assembly steps include: cleaning the parts to be curvedly welded to completely remove the oil and oxide film on the surface of the parts; assembling and fixing the parts after cleaning; in the embodiment of the present invention, in order to improve the welding effect, the local maximum assembly gap before welding is required to be no more than 0.5mm or 30%·δ (δ is the thickness of the welding parent material 23), whichever is smaller; the local maximum misalignment amount is no more than 0.2mm or 10%·δ (δ is the thickness of the welding parent material 23), whichever is smaller. Of course, the specific values ​​of the assembly gap and misalignment amount can be determined according to actual conditions.

[0086] Specifically, the parts cleaning method in step S110 may include chemical cleaning, laser cleaning, etc., and the parts assembly is performed by matching corresponding welding fixtures to ensure assembly accuracy and part surface accuracy.

[0087] For further information, see Appendix Figure 7 As shown, after performing S150, laser arc synchronous motion welding, the embodiment of the present invention further includes step S160, welding quality inspection. The specific method of welding quality inspection includes: using non-destructive testing methods to inspect welding quality, and the inspection methods include X-ray inspection, penetration inspection, etc. Among them, when the quality inspection fails in step S160, the defective part should be repaired, and the welding part after repair welding should be re-inspected for quality until it passes the inspection.

[0088] Specifically, in one embodiment of the present invention, the adjustment of parameters such as laser power and welding current in step S150 can adopt measures such as slow increase before welding and slow decrease after welding to further suppress welding defects such as porosity in the welding start area and the welding end area, and further improve the welding quality of the welding start area and the welding end area.

[0089] The following is combined with Figure 1-8 A specific embodiment is used to illustrate the laser-TIG arc hybrid welding device and hybrid welding method of the present invention.

[0090] The laser-TIG arc hybrid welding device for curved welds of the embodiment of the present invention comprises: a laser welding processing head 12, an arc welding gun 2, a connecting seat 13, a clamping assembly and a driving assembly, wherein the laser welding processing head 12 is used to output a laser beam 1 for welding, and the arc welding gun 2 is used to output an arc for welding. Among them, the laser beam 1 output by the laser welding processing head 12 and the arc output by the arc welding gun 2 act on the same molten pool, and the arc welding gun 2 can rotate around the linear direction of the laser beam 1 as an axis. The laser welding processing head 12 is arranged on the connecting seat 13; the clamping assembly can be rotatably connected to the connecting seat 13, and the clamping assembly is used to clamp the arc welding gun 2 and keep the arc welding gun 2 in a preset tilted state; the driving assembly is used to drive the clamping assembly and the arc welding gun 2 to rotate or position around the laser beam 1 in the linear direction. The connection seat 13 includes: a horizontal plate 132 and a sleeve 133. The side of the laser welding processing head 12 outputting the laser beam 1 is arranged on the horizontal plate 132. The middle of the sleeve 133 is a through hole 1331 for transmitting the laser beam 1. The central axis of the sleeve 133 coincides with the laser beam 1. The clamping assembly includes a rotating sleeve 16 and a clamping arm 19. The rotating sleeve 16 is sleeved on the outer peripheral wall of the sleeve 133. One end of the clamping arm 19 is fixed to the outer peripheral wall of the rotating sleeve 16. The other end of the clamping arm 19 is connected to the arc welding gun 2. A first tapered roller bearing 15 and a second tapered roller bearing 17 may be arranged between the rotating sleeve 16 and the sleeve 133. The inner rings of the first tapered roller bearing 15 and the second tapered roller bearing 17 are sleeved on the outer peripheral wall of the sleeve 133, and the outer rings of the first tapered roller bearing 15 and the second tapered roller bearing 17 are sleeved on the inner wall of the rotating sleeve 16. The first tapered roller bearing 15 and the second tapered roller bearing 17 are used to realize the relative rotation between the rotating sleeve 16 and the sleeve 133. The driving assembly includes a rotating motor 14, which is used to drive the rotating sleeve 16 to rotate or position around the linear direction of the laser beam 1 as the rotation axis. The connecting seat 13 also includes a vertical plate 131, which is connected to the horizontal plate 132, and the rotating motor 14 is fixedly connected to the vertical plate 131, thereby realizing the fixation of the rotating motor 14. An annular boss 1332 is provided at one end of the outer peripheral wall of the sleeve 133, and an external thread 1333 is provided at the other end of the outer peripheral wall of the sleeve 133. The rotating sleeve 16 is sleeved between the annular boss 1332 and the external thread 1333, and the external thread 1333 is threadedly connected with a threaded retaining ring 18. The driving assembly also includes a first gear 141, and a second gear 161 is provided on the outer peripheral wall of the rotating sleeve 16. The first gear 141 and the second gear 161 are meshed with each other for transmission. The rotating motor 14 is fixed on the connecting seat 13, and the driving shaft of the rotating motor 14 is parallel to the rotating shaft of the rotating sleeve 16. An anti-splash lens 122 is provided between the laser welding processing head 12 and the sleeve 133, and a horizontal blowing air curtain 24 is also provided at the lower end of the sleeve 13.

[0091] The above laser-TIG arc hybrid welding device is used to weld a curved weld of 6061 aluminum alloy (wall thickness 3 mm) with a curvature radius of 30 mm, and the following steps are used:

[0092] S110: Parts cleaning and assembly. Clean the parts to be curved welded to completely remove the oil and oxide film on the surface of the parts; assemble and fix the parts after cleaning, requiring the local maximum assembly gap before welding to be no more than 0.5mm; the local maximum misalignment amount shall not exceed 0.2mm.

[0093] S120: Robot teaching. The robot drives the laser-TIG arc hybrid welding device to realize the pre-welding teaching of the curved weld. During the teaching process, the robot controls the laser beam 1 to move along the welding track 3, that is, the revolution function of the hybrid welding is realized by the robot.

[0094] S130: Welding trajectory compensation correction. Based on the welding teaching trajectory of the laser beam, the optimal laser arc geometric position state of each teaching point is obtained by calculation, that is, the arc mid-axis plane 10 at each teaching point and the tangent line 11 of the welding trajectory 3 at the laser action point maintain an angle α=10°. At this time, the TIG welding gun 20 and the laser beam 1 always maintain a paraxial state, and the inclination angle between the TIG welding gun 20 and the central axis of the welding wire and the normal of the welding surface is 45°, the dry extension of the welding wire is 10mm, the preset value of the wire spacing is 5mm, and the diameter of the welding wire is 1.2mm. The force on the liquid metal at the top of the molten pool 9 tends to be balanced, that is, the phenomenon that the molten pool tends to flow out when the curvature radius of the curved weld is small is solved, and the poor fusion defect or undercut defect at the weld toe position on the front of the weld is fundamentally suppressed.

[0095] S140: Motion control programming. By controlling the transmission ratio of the first gear 141 and the second gear 161 in the hybrid welding device to 3, the motion control programming after the welding trajectory compensation correction is completed, that is, the hybrid welding device realizes the real-time rotation and position adjustment of the TIG arc around the laser beam, that is, the self-rotation function of the hybrid welding device is realized.

[0096] S150: Laser arc synchronous motion welding. According to the taught welding trajectory, the arc geometry, welding speed, laser power, welding current and other welding parameters are confirmed again, that is, the laser power is kept at 2800W, the welding speed is 1.5m / min, and the TIG welding current is 60A, and finally the laser-TIG arc hybrid welding of the curved weld is completed.

[0097] S160: Welding quality inspection. Use non-destructive testing methods to inspect welding quality. If the quality inspection fails, the defects exceeding the standard should be repaired. The welding parts after repair welding should be re-inspected until they pass the inspection. The inspection methods include X-ray inspection, penetration inspection, etc.

[0098] The above steps have been verified to effectively overcome the poor fusion or undercut defects at the weld toe on the front side of the weld that are prone to occur when the curvature radius of the curved weld is small.

[0099] In summary, the laser arc hybrid welding device of the present invention realizes the arc column area and welding wire of the paraxial TIG arc welding on both sides of the laser beam through the rotating motor and the gear meshing transmission, and rotates around the axis of the laser beam while keeping the arc spacing and the wire spacing unchanged, that is, the self-rotation function of the laser-TIG arc paraxial composite wire filling welding is realized, and the light, wire and arc always act on the same molten pool to achieve a good composite welding effect.

[0100] The laser-TIG arc hybrid welding method of the present invention realizes the revolution function of the laser arc hybrid welding with the help of a manipulator, and cooperates with its own rotation function to maintain a preset angle between the laser arc hybrid welding plane and the welding trajectory tangent of the curved weld. The preset angle changes with the change of the curvature radius of the curved weld, and changes the stress state of the liquid metal at the top of the molten pool, thereby affecting the flow of the liquid metal in the molten pool. It is particularly beneficial to eliminate poor fusion or undercut defects at the front weld toe of the weld that are easily generated when the curvature radius of the curved weld is small, and is more conducive to improving the quality of laser arc hybrid welding.

[0101] It should be clear that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the embodiments of the method, the relevant parts can refer to the partial description of the device embodiment. The present invention is not limited to the specific steps and structures described above and shown in the figures. In addition, for the sake of brevity, a detailed description of known method technologies is omitted here.

[0102] The above is only an embodiment of the present application and is not limited to the present application. For those skilled in the art, the present application may have various changes and variations without departing from the scope of the present invention. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A laser-TIG arc hybrid welding method for a curved weld, using a laser-TIG arc hybrid welding device for a curved weld, the device comprising a laser welding processing head (12) and an arc welding gun (2); the laser welding processing head (12) is used to output a laser beam (1) for welding; the arc welding gun (2) is a TIG welding gun, which is used to output a TIG arc for welding; wherein, The laser beam (1) output by the laser welding processing head (12) and the TIG arc output by the arc welding gun (2) act on the same molten pool (9), and the arc welding gun (2) can rotate around the linear direction of the laser beam (1) as an axis, and is characterized in that the laser-TIG arc hybrid welding method comprises the following steps: Robot teaching: a robot is used to drive the laser-TIG arc hybrid welding device to realize pre-welding teaching of curved welds. During the teaching process, the robot controls the laser beam (1) to move along the welding track (3); Welding trajectory compensation correction: Based on the robot teaching motion trajectory of the laser beam (1), the optimal geometric position state of the laser welding processing head (12) and the arc welding gun (2) at each teaching point is calculated; wherein the method for calculating the optimal geometric position state of the laser welding processing head (12) and the arc welding gun (2) at each teaching point comprises the following steps: calculating the magnitude and direction of the force applied by the laser welding processing head (12) and the arc welding gun (2); calculating the centrifugal force of the liquid metal in the molten pool (9); adjusting the angle of the arc welding gun (2) so that the force applied by the laser welding processing head (12) and the arc welding gun (2), the surface tension of the liquid metal in the molten pool (9), the thrust of the welding wire (22) and the centrifugal force of the liquid metal in the molten pool (9) are balanced; Motion control programming: by controlling the rotation angle of the arc welding gun (2) to change the geometric position state of the arc welding gun (2), the motion control programming after welding trajectory compensation correction is completed; Laser arc synchronous motion welding: according to the determined hybrid welding parameters, confirm the laser arc geometric position state, welding speed, laser power, welding current welding parameters, and implement the laser-TIG arc hybrid welding of the curved weld according to the preset motion control programming program until the welding is completed; Welding quality inspection: Use non-destructive testing methods to inspect the welding quality. When the quality inspection fails, the defects that exceed the standard should be repaired, and the welding parts after repair welding should be re-inspected until they pass the inspection.

2. The laser-TIG arc hybrid welding method for curved welds according to claim 1, characterized in that: The laser-TIG arc hybrid welding device for curved welds also includes: A connecting seat (13), on which the laser welding processing head (12) is arranged; A clamping assembly, the clamping assembly being rotatably connected to the connecting seat (13), the clamping assembly being used to clamp the arc welding gun (2) and keep the arc welding gun (2) in a preset tilted state; A driving component is used to drive the clamping component and the arc welding gun (2) to rotate or position around the straight line direction of the laser beam (1).

3. The laser-TIG arc hybrid welding method for curved welds according to claim 2, characterized in that: The connecting seat (13) comprises: a vertical plate (131), a horizontal plate (132) and a sleeve (133); the vertical plate (131) is perpendicular to the horizontal plate (132) and is installed on the side of the laser welding processing head; the side of the laser welding processing head (12) outputting the laser beam (1) is arranged on the horizontal plate (132); the middle of the sleeve (133) is a through hole (1331) for transmitting the laser beam (1); and the central axis of the sleeve (133) coincides with the straight line on which the laser beam (1) is located.

4. The laser-TIG arc hybrid welding method for curved welds according to claim 3, characterized in that: The clamping assembly comprises a rotating sleeve (16) and a clamping arm (19); the rotating sleeve (16) is sleeved on the outer peripheral wall of the sleeve (133), and a bearing is arranged between the rotating sleeve (16) and the sleeve (133); the middle part of the clamping arm (19) is fixed to the periphery of the rotating sleeve (16); one end of the clamping arm (19) clamps and fixes a TIG welding gun (20), and the other end of the clamping arm (19) clamps and fixes a wire guide nozzle (21); the TIG welding gun (20) and the wire guide nozzle (21) are arranged at the front and rear sides of the laser beam (1); and the welding wire (22) is fed to the front edge of the welding hole through the wire guide nozzle (21).

5. The laser-TIG arc hybrid welding method for curved welds according to claim 4, characterized in that: The driving assembly comprises a rotating motor (14), and the rotating motor (14) is used to drive the rotating sleeve (16) to rotate or position around a linear direction of the laser beam (1) as a rotating axis.

6. The laser-TIG arc hybrid welding method for curved welds according to claim 4, characterized in that: An annular boss (1332) is provided at one end of the outer peripheral wall of the sleeve (133), and an external thread (1333) is provided at the other end of the outer peripheral wall of the sleeve (133). The rotating sleeve (16) is sleeved between the annular boss (1332) and the external thread (1333), and the external thread (1333) is threadedly connected to a threaded retaining ring (18).

7. The laser-TIG arc hybrid welding method for curved welds according to claim 5, characterized in that: The driving assembly further comprises a first gear (141), and a second gear (161) is provided on the outer peripheral wall of the rotating sleeve (16), and the first gear (141) and the second gear (161) are meshed with each other for transmission.

8. The laser-TIG arc hybrid welding method for curved welds according to claim 5, characterized in that: The rotating motor (14) is fixed on the connecting seat (13), and the driving shaft of the rotating motor (14) is parallel to the rotating shaft of the rotating sleeve (16).

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