Varmsveisede

Varmsveisede is a term used in Danish and Norwegian to describe a joint, seam, or component formed by heat welding. In heat welding, the surfaces of thermoplastic parts are heated to a molten state and then pressed together, forming a fused bond as the material cools. The term refers to both the joints themselves and products manufactured using this method.

Common heat welding methods include hot plate welding, where parts are pressed between heated plates; ultrasonic welding, which uses high-frequency vibration to generate heat at the interface; vibration welding, where parts are held and vibrated to create heat through friction; spin welding for cylindrical components; infrared welding; and hot gas welding. The choice depends on material, geometry, production rate, and required strength.

Materials commonly involved are thermoplastics such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), and others. Design considerations for varmsveisede joints include joint geometry (weld beads, overlap, groove design), surface preparation, consistent heat application, and controlled dwell time and pressure to ensure a strong bond and minimize warping. Limitations include unsuitability for thermosetting plastics or metals, the need for precise tolerances and process control, and potential heat distortion if parts are not adequately clamped; repairs can be difficult.

Applications often encompass automotive components, packaging, medical devices, consumer appliances, plumbing systems (HDPE, PP), and enclosures. Quality is assessed through bond-strength testing (tensile, peel), leak testing, and non-destructive methods such as ultrasonic or infrared inspection. Standards and practices vary by industry and region.