METHOD FOR PRODUCING LONGITUDINALLY WELDED HELICALLY CORRUGATED METAL TUBING

摘要

The invention relates to a method for producing longitudinally welded helically corrugated metal tubing. A metal strip pulled from a strip supply is formed into tubing with a longitudinal slit. The longitudinal slit is sealed by welding and the corrugation is preferably produced by a corrugation tool that is supported eccentrically and at an angle to the tubing axis freely rotatable in a rotationally driven corrugator head and that rolls off the surface of the tubing. The met al strip as well as the uncorrugated metal tubing is advanced by a feed device that i s provided between the welding point and the corrugation unit. A second feed device (8) engages the corrugated tubing (7) directly behind the corrugation unit (6). The feed rate of this second feed device is slower than the forward fee d rate of the corrugated tubing (7) which results from the pitch of the corrugator disk and the rotational speed of the corrugator head.