Laser-welding of heat exchanger plates to incorporate passages between them, clamps them, welds together around location of passage to be introduced, then cuts passage out

摘要

Two heat exchanger plates (1a, 1b) are clamped together. The clamping location is near the edge (2) of a hole which will be introduced later, to form a passage through the plates. The plates are welded together. The weld seam (9) produced, surrounds and marks the edge of the hole. The diameter of the weld seam is at least that (X) of the hole to be introduced later. The hole is then cut in the two heat exchanger plates which have been welded together. In a variant, each heat exchanger plate (1a, 1b) already includes a clamping hole (3) within the edge (2) of the passage to be introduced. Following welding, the clamping hole is widened to form the passage opening. At least two penetrating holes are cut in each plate. Two adjacent weld seams marking the edge of the passage, are used to weld the plates together. These seams overlap, at least partially. The hole for the passage is cut in the region where the overlapping weld seam extends into both heat exchanger plates. The heat exchanger plate pairs produced, are welded together along their outer edges, which are bent up. Between the outer edges, bending forms a V-shaped groove for welding. Closely-adjacent regions near the groove, lie flat together. The seam runs in the V-shaped groove. The plates have pressed formations. During pressing, the plate edges are caused to bend up. The weld seams are produced by laser welding.