摘要 |
<p>Formation of a closed tubular casing using a fixed, programmable-laser welding stand involves progressively moving the two edges of a strip to form a joining line, applying a fine strip of weakly-reflecting liquid or paste over the join, adjusting the relative distance of the laser beam and the join so that beam is focussed on the join, and relative displacement of the beam and the join. The welding stand (2) comprises a device (10) for the continuous application of the weakly reflecting material into a container, and a laser beam emission device (9) located downstream from the former device (10). The device (10) for the continuous application of the weakly reflecting material is in the form of either a wheel supplied by gravity from the reservoir and supported on the joining line (5), or a spraying nozzle supplied under pressure from the reservoir. A cleaning device (18) for removing residues of the weakly reflecting material is provided downstream of the laser beam emission device. The thin strip (3) whose edges are to be joined is selected from aluminum or copper. The weakly-reflecting material (6) is a composition comprising at least one pigment such as micronized carbon and at least one binder selected from polyunsaturated or aromatic hydrocarbons such as benzol.</p> |