摘要 |
In the process a strip (2) of a thermoplastic foam is, before forming, heated on its subsequent tube inside and, after forming and welding of the abutting seam, heated briefly on the outside to the thermoelastic or thermoplastic state and subsequently cooled. As a result, the tubes are dimensionally stable and stress-free. The continuously fed strip (2) is conveyed by means of an endless circulating belt (8) which has a rough surface and conveys the strip (2) through a first heating device (7), a forming funnel (10), a cooled forming tube (14), a welding device (19), a pressing device (20), a second heating device (24) and a cooling device (27). The tubes are suitable in particular for insulation purposes in sanitary installations. <IMAGE> |