The present disclosure discloses a welding gas shielding device, a laser filler wire welding system and a welding method. The welding gas shielding device comprises an upper shielding gas dragging cover device and a back shielding gas device. The laser filler wire welding system comprises a welding gas shielding device, a height adjusting mechanism, a wire feeding system, a laser system, a numerical control console and the like. The welding gas shielding device for narrow gaps made of dissimilar materials is reasonable in structural design, gas shielding can be carried out on the upper area and the lower area of a welding area in the welding process of the narrow gaps made of dissimilar materials, the problem that laser narrow-gap welding gas shielding is insufficient and unstable is solved, the weld joint cooling speed can be adjusted and controlled, the shielding effect is enhanced, and the welding efficiency is improved.

The present disclosure discloses a welding gas shielding device, a laser filler wire welding system and a welding method. The welding gas shielding device comprises an upper shielding gas dragging cover device and a back shielding gas device. The laser filler wire welding system comprises a welding gas shielding device, a height adjusting mechanism, a wire feeding system, a laser system, a numerical control console and the like. The welding gas shielding device for narrow gaps made of dissimilar materials is reasonable in structural design, gas shielding can be carried out on the upper area and the lower area of a welding area in the welding process of the narrow gaps made of dissimilar materials, the problem that laser narrow-gap welding gas shielding is insufficient and unstable is solved, the weld joint cooling speed can be adjusted and controlled, the shielding effect is enhanced, and the welding efficiency is improved.

A joint structure includes: a first same-type metal member; a second same-type metal member that can be mutually welded with the first same-type metal member; and a different-type member that has a penetrating portion, is interposed between the first same-type metal member and the second same-type metal member. In the plate thickness direction of an emission region in which a laser beam is emitted toward the penetrating portion, the plate thickness at the emission region of the first same-type metal member positioned on the side on which the laser beam is emitted is a predetermined thickness corresponding to a first gap. The first same-type metal member and the second same-type metal member are fused and bonded together via the penetrating portion, and the different-type member is compressed and fixed, such that the different-type member is fixed to the first same-type metal member and the second same-type metal member.

A joint structure includes: a first same-type metal member; a second same-type metal member that can be mutually welded with the first same-type metal member; and a different-type member that has a penetrating portion, is interposed between the first same-type metal member and the second same-type metal member. In the plate thickness direction of an emission region in which a laser beam is emitted toward the penetrating portion, the plate thickness at the emission region of the first same-type metal member positioned on the side on which the laser beam is emitted is a predetermined thickness corresponding to a first gap. The first same-type metal member and the second same-type metal member are fused and bonded together via the penetrating portion, and the different-type member is compressed and fixed, such that the different-type member is fixed to the first same-type metal member and the second same-type metal member.

An additive manufacturing machine that includes a wire supply including a wire drive configured to advance a wire at a wire feed rate and a wire heater configured to apply resistive heating to heat the wire. The additive manufacturing machine includes an additive head for emitting a laser beam to weld the wire to a substrate, a sensor configured to detect a weld parameter, and a controller operatively connected to the wire supply, additive head, and sensor. The controller is configured to determine a failure mode of the weld as the laser beam welds the wire to the substrate based at least in part upon the weld parameter. In response to determining the failure mode, the controller is configured to adjust at least one of the wire feed rate, the resistive heating, and a power of the laser beam as the laser beam welds the wire to stabilize the weld.

An additive manufacturing machine that includes a wire supply including a wire drive configured to advance a wire at a wire feed rate and a wire heater configured to apply resistive heating to heat the wire. The additive manufacturing machine includes an additive head for emitting a laser beam to weld the wire to a substrate, a sensor configured to detect a weld parameter, and a controller operatively connected to the wire supply, additive head, and sensor. The controller is configured to determine a failure mode of the weld as the laser beam welds the wire to the substrate based at least in part upon the weld parameter. In response to determining the failure mode, the controller is configured to adjust at least one of the wire feed rate, the resistive heating, and a power of the laser beam as the laser beam welds the wire to stabilize the weld.

A first metal pipe is welded to a second metal pipe in a method of laying pipeline, for example from a pipe-laying vessel at sea. The metal pipes may have an outer diameter greater than 150 mm and a pipe wall thickness of greater than 15 mm. The first pipe and the second pipe are brought together prior to welding so as to sandwich a third type of metal material between the pipe ends. The thickness of the third type of material, immediately before welding may be between 0.05 mm and 2 mm. The third metal material is melted together with the metal material of the first pipe and the second pipe.

A first metal pipe is welded to a second metal pipe in a method of laying pipeline, for example from a pipe-laying vessel at sea. The metal pipes may have an outer diameter greater than 150 mm and a pipe wall thickness of greater than 15 mm. The first pipe and the second pipe are brought together prior to welding so as to sandwich a third type of metal material between the pipe ends. The thickness of the third type of material, immediately before welding may be between 0.05 mm and 2 mm. The third metal material is melted together with the metal material of the first pipe and the second pipe.

A laser welding apparatus (1) includes a laser welding head (5) configured to irradiate a workpiece (10) with laser light, a welding filler feeding mechanism (6) configured to supply a welding material to a position on which laser welding is performed, and a hollow structural moving mechanism (100) configured to move a welding unit (50) including the laser welding head and the welding filler feeding mechanism. The hollow structural moving mechanism has an insertion portion (3a) through which wire materials (41 and 62) of the laser welding head and the welding filler feeding mechanism are inserted.

A laser welding apparatus (1) includes a laser welding head (5) configured to irradiate a workpiece (10) with laser light, a welding filler feeding mechanism (6) configured to supply a welding material to a position on which laser welding is performed, and a hollow structural moving mechanism (100) configured to move a welding unit (50) including the laser welding head and the welding filler feeding mechanism. The hollow structural moving mechanism has an insertion portion (3a) through which wire materials (41 and 62) of the laser welding head and the welding filler feeding mechanism are inserted.