| 摘要 |
The present process of so-called thermal welding serves for welding the edges of webs of plastics, especially PVC and copolymers, the edges to be welded being heated until they soften and simultaneously pressed together. In order to use higher temperatures in the welding, according to the present process the edges to be welded are covered on both free outer surfaces with one separating layer in each case before being pressed together and then the edges are pressed together over the entire length between heated rails for an adjustable welding time and with an adjustable welding pressure. Subsequently the separating layers adhering lightly at the edge regions can be stripped off the webs welded together at their edges. A device of frame-like design is provided for carrying out this process, having a support table for the two-part welding tool and a roll stack for drawing in the separating layers. <IMAGE> |
