A METHOD AND APPARATUS FOR SPIRALLY WINDING A THERMOPLASTIC PROFILE IN THE MANUFACTURE OF WELDED PLASTIC TUBES

摘要

The present invention relates to a method of spirally winding a thermoplastic profile in the manufacture of welded plastic tubes, as well as to a winding apparatus for manufacturing a spirally wound tube. A thermoplastic profile (1) is received on a plurality of sliding means (2,3) being arranged in an axial direction of the tube (4) to be manufactured and defining an essentially cylindrically shaped winding surface with a diameter essentially corresponding to the inner diameter of said tube (4). The profile (1) is directed along a spiral path (S) towards the previous turn of said profile (1) in order to force opposite edges (1a, 1b) of said profile together for welding. The radial position of said sliding means is adjusted to control the tension in said thermoplastic profile (1) and the force with which it constricts itself around said winding surface as defined by said sliding means (2,3).