Basic Components of a Flexible PU Foam Production Line: Liner Paper (Film) Device

In a continuous block foam machine, high-strength kraft paper and polyethylene film are commonly used as isolation liners between the foam block, the conveyor belt, and the templates. In essence, they function as actual forming molds (troughs). When producing rectangular foam blocks using a vertical foaming machine, polyethylene film is typically used for the short sides, while kraft paper is used for the long sides. For cylindrical foam blocks, polyethylene film is used.

The paper (film) feeding mechanism generally consists of a paper (film) unwinder, guide rollers, tension rollers, and a paper folder (for bottom paper).

In high-flow horizontal foaming machines, the foam width usually exceeds 2 meters, requiring three paper feeding systems: bottom paper and two side papers. Foaming machines utilizing a balanced press plate process include an independent top paper feeding and collecting system. To allow for foam block width adjustment, cutting rotary blades are installed on both side edges.

Vertical foaming machines typically do not have a retrieval device for liner paper (film); instead, the liner paper or film is manually removed after the foam is cut.