For the processing of EVA, PVC and PUR films into bags, we use advanced welding systems (rotary and sliding tables) from Kiefel, in which high-frequency (HF) welding technology is used.
In HF welding, a high-frequency field is applied directly to the films. The molecules of the foils are set into vibration and the resulting friction generates the heat required for welding. This heating causes the films to liquefy and can then be pressed together. As a result, a highly resilient (molecularly bonded) weld seam is available after cooling.
PE and PP films are processed by means of heat contact or heat pulse welding. The films are heated on the surface and joined together by means of the necessary contact pressure and time.
Both processes allow the welding of tubes between the film layers as well as the integration of connection ports in the film surface.