Patent ID: 8362385
Filing Date: 2013-01-29
Classification: B23K,F16L

Abstract:
1. Method for sealing collars of double-wall bellows, in which a continuous butt-sealed rim of a collar defined by corresponding concentric ends, devoid of undulations, of a first, radially inner wall, and a second, radially outer wall, of the bellows is obtained as a continuous butt-weld bead on the corresponding rims, arranged radially adjacent to each other, of the ends of the first and second walls, comprising the phases of: preparing the rims of the concentric ends of said first and second walls such that, before welding, they are radially spaced apart from each other by a preset clearance, butt welding the said previously prepared rims with a laser beam directed parallel to an axis of symmetry of the collar, making the latter turn around said axis to progressively expose an entire perimeter of said rims of the ends of the first and second walls to the laser beam, said laser welding phase being carried out by simultaneously pressing said rims against each other with a preset force via radial clamping means, so as to create a butt weld on the rims without filler metal and of a preset depth; wherein: said preparation phase of said rims of the concentric ends of the first and second walls is carried out such that the rim of the second wall projects in an axial direction with respect to that of the first wall for a preset length.