Process and apparatus for welding plastics profiles

摘要

The invention relates to a process for welding plastics profiles, in particular for forming window frames, in which the strained plastics profiles are pressed initially for a short time with their bonding surfaces against a hot plate welding tool which can be moved in and can be heated by a heating circuit which can be closed in dependence on at least one temperature sensor and are pressed against each other and thereby welded to each other immediately after achieving a predetermined initial melting of the bonding surfaces. In order to rule out cooling of the middle area of the hot plate welding tool during the initial melting operation of the bonding surfaces of the plastics profiles to be welded to each other, and consequently to ensure satisfactory quality and high strength of the weld, a short time before or at the beginning of the initial melting of the bonding surfaces of the plastics profiles the temperature-controlled heating circuit is interrupted for a short time and the hot plate welding tool is heated uninterruptedly by means of a second heating circuit during this time.