阅读说明：本技术 十字型接头双侧旋转激光-tig电弧的焊接方法及夹持工装 (Welding method and clamping tool for bilateral rotation laser-TIG electric arc of cross joint ) 是由 彭进 许红巧 于 2020-05-28 设计创作，主要内容包括：本发明涉及激光焊接技术领域,具体的说是十字型接头双侧旋转激光-TIG电弧的焊接方法及夹持工装。一种十字型接头双侧旋转激光-TIG电弧的焊接方法,由设置在十字型接头上部两侧的两个激光发射头和设置在十字型接头下部两侧的两个TIG焊枪配合对十字型接头进行焊接,激光发射头和TIG焊枪各自以平行于自身轴线的中心线旋转,且位于对角位置的激光发射头和TIG焊枪保持同轴；焊接前在十字型接头上部的两侧位置预置与激光发射头所发射的激光束配合的金属粉末,焊接过程中通过位于十字型焊接头下部两侧位置的保护气喷嘴对熔池液态金属进行托举。本发明可解决十字交叉型接头上部的角焊缝下榻、咬边缺陷,下部的角焊缝凸起造成应力集中,以及接合面未熔合的问题。(The invention relates to the technical field of laser welding, in particular to a welding method and a clamping tool for bilateral rotation laser-TIG (tungsten inert gas) electric arc of a cross joint. A welding method of bilateral rotation laser-TIG electric arc of a cross joint is characterized in that two laser emission heads arranged on two sides of the upper part of the cross joint and two TIG welding guns arranged on two sides of the lower part of the cross joint are matched to weld the cross joint, the laser emission heads and the TIG welding guns respectively rotate along a central line parallel to the axis of the laser emission heads and the TIG welding guns, and the laser emission heads and the TIG welding guns which are positioned at opposite angles keep coaxial; metal powder matched with laser beams emitted by the laser emitting heads is preset at the two sides of the upper part of the cross joint before welding, and molten pool liquid metal is lifted through protective gas nozzles at the two sides of the lower part of the cross joint in the welding process. The invention can solve the problems of the lower couch and undercut of the fillet weld at the upper part of the cross-shaped joint, stress concentration caused by the bulge of the fillet weld at the lower part and unfused joint surfaces.)

1. A welding method of bilateral rotation laser-TIG electric arc of a cross joint is characterized in that: the two laser emission heads arranged on the two sides of the upper part of the cross joint and the two TIG welding guns (15) arranged on the two sides of the lower part of the cross joint are matched to weld the cross joint, the laser emission heads and the TIG welding guns (15) respectively rotate along a central line parallel to the axis of the laser emission heads and the TIG welding guns (15), and the laser emission heads and the TIG welding guns (15) at opposite angles keep coaxial; metal powder (10) matched with laser beams (9) emitted by the laser emitting heads is preset at two sides of the upper part of the cross joint before welding, and molten pool liquid metal is lifted through protective gas nozzles (14) positioned at two sides of the lower part of the cross joint in the welding process.

2. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the method comprises the following steps:

1) after a first base material (11) and a second base material (12) to be welded are subjected to surface treatment to remove impurities, the first base material (11) and the second base material (12) are crossed and clamped and fixed on a welding fixture to form a cross joint to be welded;

2) respectively presetting metal powder (10) at two sides of the upper part of the cross joint to be welded;

3) respectively connecting two poles of a power supply (13) of a TIG welding gun (15) with the TIG welding gun (15) and a cross joint to be welded, starting the TIG welding gun (15), and arcing at a lower corner welding seam base metal of the TIG welding gun (15) and the cross joint to be welded; simultaneously starting a laser emitting head to emit a laser beam (9), so that the laser beam (9) melts metal powder (10) to form a molten pool and acts on an upper-corner welding seam base metal of the cross joint to be welded; the laser beam (9) and the TIG welding gun (15) keep the laser emitting head and the TIG welding gun (15) which are positioned at the diagonal positions to rotate continuously and coaxially in the welding process, and the shielding gas nozzles (14) positioned at the two sides of the lower part of the cross welding head achieve the lifting effect on molten pool liquid metal.

3. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the power supply (13) is connected with the TIG welding gun (15) and the cross joint to be welded in a direct current positive connection mode, a direct current reverse connection mode or an alternating current mode.

4. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the laser emitting head is connected with a laser, and the laser is Nd: YAG laser, CO₂A laser or a fiber laser.

5. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the first base material (11), the second base material (12) and the metal powder (10) are all made of aluminum alloy.

6. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the protective gas sprayed out by the protective gas nozzle (14) is argon or helium.

7. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the TIG welding guns (15) are coaxially distributed in the shielding gas nozzle (14).

8. The welding method of a double-sided rotating laser-TIG arc of a cross-joint as claimed in claim 1, wherein: the included angle between the axial direction of the laser emitting head and the horizontal plane is 30-80 degrees.

9. The utility model provides a welding centre gripping frock of two side rotation laser-TIG electric arcs of cross joint which characterized in that: the device comprises a rack, two bottom chucks (5) which are rotatably arranged at the bottom of the rack and used for clamping and fixing a TIG welding gun (15) and two top chucks (4) which are rotatably arranged at the top of the rack and used for clamping and fixing a laser emitting head, wherein the two bottom chucks (5) and the two top chucks (4) are distributed in a crossed and corresponding manner, and the bottom chucks (5) and the top chucks (4) which are positioned at the crossed positions are parallel to each other; the automatic feeding mechanism is characterized in that a first motor (8) is arranged at a position, located between two bottom chucks (5), on a rack, an output shaft of the first motor (8) is provided with a first bevel gear (7), the first bevel gear (7) is simultaneously meshed with two second bevel gears (6) respectively arranged at the outer edge positions of the two bottom chucks (5), a second motor (1) is arranged at a position, located between two top chucks (4), on the rack, an output shaft of the second motor (1) is provided with a third bevel gear (2), and the third bevel gear (2) is simultaneously meshed with two fourth bevel gears (3) respectively arranged at the outer edge positions of the two top chucks (4).

10. The welding clamping tool for the bilateral rotation laser-TIG electric arc of the cross joint as claimed in claim 9, wherein the welding clamping tool comprises: the disc surfaces of the bottom chuck (5) and the top chuck (4) are respectively provided with a straight slide hole (17), the slide holes (17) are distributed along the diameter direction of the corresponding bottom chuck (5) or top chuck (4) and are used for sliding matching of a corresponding laser emitting head or TIG welding gun (15), the slide holes (17) are distributed along the diameter direction of the corresponding bottom chuck (5) or top chuck (4), and the bottom chuck (5) or top chuck (4) is also provided with scale marks (18) distributed along the length direction of the corresponding slide hole (17).

Technical Field

The invention relates to the technical field of laser welding, in particular to a welding method and a clamping tool for bilateral rotation laser-TIG (tungsten inert gas) electric arc of a cross joint.

Background

Compared with the traditional welding method, the laser welding technology has the advantages of small welding deformation, deep penetration depth of welding seams, high welding efficiency and the like, so that the laser welding technology is widely applied to the manufacturing fields of aerospace, automobiles, ships and the like.

With the development of the industry in China, unconventional joints, such as cross-shaped joints, are required in some fields. At present, a cross joint is generally welded on one side and then on the other side by using a laser beam, the method has low welding efficiency, the phenomenon that a joint surface is not fused is easy to generate, and the defects of tatting and undercut of a fillet weld at the upper part are easy to occur because no extra filler metal is added, so that the stress concentration is caused by the projection of the fillet weld at the lower part, and the quality of the weld is finally influenced.

Chinese patent "cross joint laser synchronous double-beam welding method", published as 2013.02.13, discloses that two lasers are used to respectively emit a main beam a and a main beam b, the two lasers are arranged on two sides of a cross joint support plate in a mirror image manner, the main beam a is divided into a welding beam 11 and a welding beam 12, the main beam b is divided into a welding beam 21 and a welding beam 22, and the welding beam 11, the welding beam 21, the welding beam 12 and the welding beam 22 are synchronously welded. However, the method is easy to cause the defects of the lower couch and undercut of the fillet weld at the upper part, and the bottom of the fillet weld is easy to cause stress concentration due to the weld formed by excessive protruded liquid metal, thereby influencing the mechanical property of the product.

Disclosure of Invention

The invention aims to provide a welding method of bilateral rotation laser-TIG electric arc of a cross joint, improve the welding quality, provide a welding clamping tool of bilateral rotation laser-TIG electric arc of the cross joint, and facilitate the implementation of the welding method.

In order to solve the technical problems, the invention adopts the technical scheme that: a welding method of bilateral rotation laser-TIG electric arc of a cross joint is characterized in that two laser emission heads arranged on two sides of the upper part of the cross joint and two TIG welding guns arranged on two sides of the lower part of the cross joint are matched to weld the cross joint, the laser emission heads and the TIG welding guns respectively rotate along a central line parallel to the axis of the laser emission heads and the TIG welding guns, and the laser emission heads and the TIG welding guns which are positioned at opposite angles keep coaxial; metal powder matched with laser beams emitted by the laser emitting heads is preset at the two sides of the upper part of the cross joint before welding, and molten pool liquid metal is lifted through protective gas nozzles at the two sides of the lower part of the cross joint in the welding process.

Preferably, the method comprises the following steps:

1) after the first base metal and the second base metal to be welded are subjected to surface treatment to remove impurities, the first base metal and the second base metal are crossed and clamped and fixed on a welding fixture to form a cross joint to be welded;

2) respectively presetting metal powder at two side positions of the upper part of the cross joint to be welded;

3) respectively connecting two poles of a power supply of the TIG welding gun with the TIG welding gun and the cross joint to be welded, starting the TIG welding gun, and arcing at the lower corner weld joint parent metal of the TIG welding gun and the cross joint to be welded; simultaneously starting the laser emitting head to emit laser beams, so that the laser beams melt metal powder to form a molten pool and act on the upper-corner welding seam base metal of the cross joint to be welded; the laser beam and the TIG welding gun keep the laser emitting head and the TIG welding gun at opposite angles to rotate continuously and coaxially in the welding process, and the shielding gas nozzles at two sides of the lower part of the cross welding head are used for lifting molten pool liquid metal.

Preferably, the power supply is connected to the TIG welding gun and the cross joint to be welded in a direct current forward mode, a direct current reverse mode or an alternating current mode.

Preferably, the laser emitting head is connected with a laser, and the laser is Nd: YAG laser, CO₂A laser or a fiber laser.

Preferably, the first base material, the second base material, and the metal powder are all made of an aluminum alloy.

Preferably, the shielding gas sprayed by the shielding gas nozzle is argon or helium.

Preferably, the TIG welding guns are coaxially distributed in the shielding gas nozzle.

Preferably, the angle between the axial direction of the laser emitting head and the horizontal plane is 30-80 degrees.

A welding clamping tool for bilateral rotation laser-TIG electric arc of a cross joint comprises a rack, two bottom chucks rotationally arranged at the bottom of the rack and used for clamping and fixing a TIG welding gun, and two top chucks rotationally arranged at the top of the rack and used for clamping and fixing a laser emission head, wherein the two bottom chucks and the two top chucks are distributed in a crossed and corresponding manner, and the bottom chucks and the top chucks at the crossed positions are parallel to each other; the automatic feeding device comprises a rack, a first motor, a second motor, a third bevel gear, a fourth bevel gear, a third bevel gear and a motor, wherein the first motor is arranged between two bottom chucks on the rack, the first bevel gear is arranged on an output shaft of the first motor and is meshed with two second bevel gears which are respectively arranged at the outer edges of the two bottom chucks, the second motor is arranged between two top chucks on the rack, the third bevel gear is arranged on an output shaft of the second motor and is meshed with two fourth bevel gears which are respectively arranged at the outer edges of the two top chucks.

Preferably, the disc surfaces of the bottom chuck and the top chuck are respectively provided with a linear sliding hole, the sliding holes are distributed along the diameter direction of the corresponding bottom chuck or top chuck and are used for the corresponding laser emitting head or TIG welding gun to be in sliding fit, the sliding holes are distributed along the diameter direction of the corresponding bottom chuck or top chuck, and the bottom chuck or top chuck is also provided with scale marks distributed along the length direction of the corresponding sliding hole.

Advantageous effects

The invention respectively arranges rotary laser beams (which can increase the area of a melting welding seam and further increase the area of a welding seam joint surface) with a certain size as a radius at the left side and the right side of the upper part of a cross joint, respectively arranges TIG welding guns at the left side and the right side of the lower part of the cross joint, arcs at the TIG welding guns and a fillet welding seam parent metal, simultaneously arranges a shielding gas nozzle coaxial with the TIG welding guns for preventing projections (which can cause stress concentration) formed by solidification of molten pool metal at the left side and the right side of the lower part of the cross joint under the influence of gravity, and sprays shielding gas to play a role of lifting molten pool liquid metal in the welding process.

Through the welding method, the invention mainly has the following beneficial effects:

1. the shielding gas nozzle coaxial with the TIG welding gun continuously sprays a large amount of shielding gas to play a role in lifting molten pool liquid metal in the welding process, and the molten pool metal on the left side and the right side of the lower part of the crisscross joint is prevented from being solidified to form bulges under the influence of gravity, so that the stress concentration phenomenon caused by the bulges is avoided.

2. Powder is preset at the left side and the right side above the cross-shaped angle joint, so that the defects of tatting and undercut of the fillet weld at the upper part of the cross-shaped joint caused by no metal filling in the conventional welding method can be eliminated;

3. the laser beam rotates at a certain radius to increase the melting area of the welding seam, and is positioned on the same axis with the TIG welding gun, so that the problem that the joint surface of the cross joint is not fused can be solved;

4. the laser beam and the TIG welding gun are positioned on the same axis, and the laser beam can attract TIG electric arcs mutually, so that the welding stability is improved, and meanwhile, the penetration efficiency of a welding seam is increased.

According to the welding clamping tool for the bilateral rotation laser-TIG electric arc of the cross joint, the two laser emission heads and the two TIG welding guns can be synchronously controlled to synchronously rotate through the two motors, so that the coaxiality of the corresponding laser emission heads and the corresponding TIG welding guns in the rotating process can be conveniently maintained, and the matching of a laser beam and the TIG welding guns is facilitated.

Drawings

FIG. 1 is a working schematic diagram of a welding method of bilateral rotation laser-TIG electric arc of a cross joint of the invention;

FIG. 2 is a schematic view of a weld profile of a cross joint welded with a single beam in the prior art;

FIG. 3 is a schematic view of a weld profile using a cross joint laser synchronous dual beam welding method in the prior art;

FIG. 4 is a schematic view of the weld profile of a welding process using a double-sided rotating laser-TIG arc of the inventive cross joint;

FIG. 5 is a schematic structural diagram of a welding and clamping tool for a double-side rotating laser-TIG arc of a cross joint in the invention;

FIG. 6 is a schematic view of the top or bottom chuck of FIG. 5;

the labels in the figure are: 1. the device comprises a second motor, 2, a third bevel gear, 3, a fourth bevel gear, 4, a top chuck, 5, a bottom chuck, 6, a second bevel gear, 7, a first bevel gear, 8, a first motor, 9, a laser beam, 10, metal powder, 11, a first base material, 12, a second base material, 13, a power supply, 14, a shielding gas nozzle, 15, a TIG welding gun, 16, shielding gas flow, 17, a slide hole, 18 and scale marks.

Detailed Description

As shown in fig. 1, in the welding method of the double-side rotating laser-TIG arc of the cross joint according to the present invention, the cross joint is welded by two laser emitting heads disposed on both sides of the upper portion of the cross joint and two TIG welding guns 15 disposed on both sides of the lower portion of the cross joint in cooperation. The included angle alpha between the axial direction of the laser emitting head and the horizontal plane is 30-80 degrees. The laser emitting head and the TIG welding gun 15 each rotate at a certain radius with a center line parallel to their own axis, and the laser emitting head and the TIG welding gun 15 located at diagonal positions are kept coaxial. Metal powder 10 matched with laser beams 9 emitted by the laser emitting heads is preset at two sides of the upper part of the cross joint before welding, and molten pool liquid metal is lifted through protective gas nozzles 14 at two sides of the lower part of the cross joint in the welding process. The TIG welding guns 15 are coaxially distributed in the shielding gas nozzle 14, and the shielding gas flow 16 generated in the shielding gas nozzle 14 is coaxial with the TIG welding guns 15.

Specifically, the method comprises the following steps:

1) after the first base metal 11 and the second base metal 12 to be welded are subjected to surface treatment to remove impurities, the first base metal 11 and the second base metal 12 are crossed and clamped and fixed on a welding fixture to form a cross joint to be welded; the widths of the first parent metal 11 and the second parent metal 12 are both 1-6mm, and the materials are aluminum alloys;

2) respectively presetting metal powder 10 at two sides of the upper part of the cross joint to be welded, wherein the material of the metal powder 10, the first base metal 11 and the second base metal 12 are aluminum alloy;

3) connecting two poles of a power supply 13 of the TIG welding gun 15 with the TIG welding gun 15 and the cross joint to be welded respectively, starting the TIG welding gun 15, arcing at a lower corner welding seam parent metal of the TIG welding gun 15 and the cross joint to be welded, wherein the welding speed is 0.1m/min-2m/min, and the connecting method of the power supply 13 with the TIG welding gun 15 and the cross joint to be welded is direct current positive welding (a positive electrode of the power supply 13 is connected with the parent metal, a negative electrode is connected with the TIG welding gun 15), direct current reverse welding (a negative electrode of the power supply 13 is connected with the parent metal, and a positive electrode is connected with the TIG welding gun 15) or alternating current form (the form is irrelevant to polarity). In this embodiment, since the aluminum alloy is welded, a direct current reverse connection or an alternating current is adopted, and the arc generates a cathode cleaning effect on the oxide film on the surface of the base metal during the direct current reverse connection. Because the oxide film has a high melting point (such as Al2O3, the melting point is 2050 ℃), the oxide film is difficult to melt during welding, often covers the surface of a welding pool, and is not melted if not removed in time, and the oxide film can not be fused after being cooled and solidified, so that the surface of a welding seam forms wrinkle or the defects of pores, slag inclusion and the like are generated inside the welding seam, and the quality of the welding seam is directly influenced; and simultaneously starting the laser emitting head to emit laser beams 9, so that the laser beams 9 melt metal powder 10 to form a molten pool and act on the upper-corner weld seam parent metal of the cross joint to be welded. The laser emission head is connected with a laser, the laser power is 500-8000W, and the laser is Nd: YAG laser, CO₂A laser or a fiber laser. The output type of the laser can be continuous output or pulse output; the laser beam 9 and the TIG welding gun 15 keep the laser emitting head and the TIG welding gun 15 which are positioned at the diagonal positions to rotate continuously and coaxially in the welding process, the rotating frequency of the laser beam 9 is 0-300Hz, and the rotating radius of the laser beam 9 is 0-2 mm. The protective gas nozzles 14 positioned at the two sides of the lower part of the cross welding head achieve the lifting effect on molten pool liquid metal, and the protective gas sprayed by the protective gas nozzles 14 is argon or helium.

The performance of the cross joint manufactured by the invention is compared with the performance of the cross joint in the prior art as shown in figures 2-4: FIG. 2 is a schematic view of the weld profile of a cross joint welded with a single beam. It is seen that the unfusion of the joining surfaces is likely to occur. And because no extra filler metal is added, the defects of undercutting and undercutting of the fillet weld at the upper part easily occur, and the weld formed by excessive convex liquid metal appears at the bottom of the fillet weld, so that stress concentration is easily caused. FIG. 3 is a schematic view of the shape of a weld joint by using the cross joint laser synchronous double-beam welding method of the Chinese patent. This method can be seen to avoid the occurrence of the phenomenon of fusion failure of the joint surface. However, since no additional filler metal is added, the fillet weld undercut defect at the upper part is easy to occur, and the weld formed by excessive liquid metal protruding from the bottom of the fillet weld occurs, so that stress concentration is easy to cause. FIG. 4 is a schematic view of the weld morphology of the welding method using the cross joint bilateral rotation laser-TIG arc of the present invention. The upper and lower welding seams of the fillet weld are formed uniformly, and the formation of welding defects such as undercut, bed lowering and the like is avoided. And because the left side and the right side below the cross have the effect of protective gas, the molten pool liquid metal on the left side and the right side below the cross is not easy to bulge but is concave to a certain degree, and the concave fillet weld is beneficial to improving the quality of the weld, and the phenomenon of stress concentration can not occur.

The welding and clamping tool for the bilateral rotation laser-TIG electric arc of the cross joint comprises a frame (a conventional frame, which is omitted in the drawing), two bottom chucks 5 which are rotatably arranged at the bottom of the frame and are used for clamping and fixing a TIG welding gun 15, and two top chucks 4 which are rotatably arranged at the top of the frame and are used for clamping and fixing a laser emitting head, wherein the two bottom chucks are provided with a plurality of grooves. The top left chuck 4 and the bottom right chuck 5 are corresponding and parallel, and the top right chuck 4 and the bottom left chuck 5 are corresponding and parallel.

A first motor 8 is arranged on the frame between the two bottom chucks 5, a first bevel gear 7 is arranged on an output shaft of the first motor 8, and the first bevel gear 7 is meshed and connected with two second bevel gears 6 respectively arranged at the outer edges of the two bottom chucks 5. A second motor 1 is arranged on the frame between the two top chucks 4, a third bevel gear 2 is arranged on an output shaft of the second motor 1, and the third bevel gear 2 is meshed and connected with two fourth bevel gears 3 respectively arranged at the outer edges of the two top chucks 4. The laser emitting heads are clamped on the top chuck 4, the TIG welding guns 15 and the shielding gas nozzles 14 are clamped on the bottom chuck 5, and then the first motor 8 and the second motor 1 can synchronously rotate to drive the two laser emitting heads and the two TIG welding guns 15 to synchronously rotate, so that the corresponding laser emitting heads and the TIG welding guns 15 can be maintained to be coaxial in the rotating process, and the matching of the laser beams 9 and the TIG welding guns 15 is facilitated.

As shown in fig. 6, linear slide holes 17 are respectively provided on the disk surfaces of the bottom chuck 5 and the top chuck 4, and the slide holes 17 are distributed along the diameter direction of the corresponding bottom chuck 5 or top chuck 4 and slidably engaged with the corresponding laser emitting head or TIG welding gun 15. The sliding holes 17 are distributed along the diameter direction of the corresponding bottom chuck 5 or the top chuck 4, and the turning radius of the laser emitting head or the TIG welding gun 15 can be adjusted through the sliding holes 17 according to the welding design requirements. And the bottom chuck 5 or the top chuck 4 is also provided with scale marks 18 distributed along the length direction of the corresponding slide hole 17, and the turning radius of the laser emitting head or the TIG welding gun 15 is accurately adjusted through the scale marks 18.