B29C 65/342

Joining {or sealing} of preformed parts {, e.g. welding of plastics materials}; Apparatus therefor by heating, with or without pressure using heated elements which remain in the joint, e.g. "verlorenes Schweisselement" {characterised by the type of heated elements which remain in the joint comprising at least a single wire, e.g. in the form of a winding}