Patent ID: 6166348
Filing Date: 2000-12-26
Classification: B21C,B23K

Abstract:
A process for the manufacture of finned tubes made of metal where at least one endless strip, forming the fins, is wrapped around a rotating tube body in helical fashion, a narrow edge of the strip facing the tube body being joined to the tube surface using a filler, by means of a welding device and where the working end of the welding device is inserted into a free wedge-shaped space between the tube surface and the strip to be wrapped, the improvement comprising the welding device being guided at the same angle relative to the tube axis as the strip forming the fins to be fed in, the welding device being used to apply a welding bead which runs exactly in the area of the joint between the strip and the tube surfaces, to the tube surface using a filler, before the narrow edge of the strip to be joined makes contact, the welding bead being as wide as the thickness of the strip and forming a welding seam having a constant, small thickness over its entire width, the narrow edge of the strip to be joined being pressed into the welding bead while it is still liquid.