A METHOD AND APPARATUS IN THE MANUFACTURE OF A SPIRALLY WOUND AND WELDED TUBE

摘要

A method and apparatus in the manufacture of a spirally wound and welded tube is disclosed. A thermoplastic profile is slid along a path on a slider arranged in an axial direction of the tube and defining a cylindrically shaped winding surface with a diameter corresponding to the inner diameter of the tube to be manufactured. The profile is directed along a spiral path towards a previous turn of said profile by means of radial rollers spaced along said spiral path by adjusting the position of the rollers: Opposite edges of said profile turns are welded together by providing an extruded welding mass between said profile turns. The welded tube is fed from the welding station by means the rollers by sliding it onto a rotating support.