Long fiber injection process (PU-LFI)

Long fiber injection process (PU-LFI) is a relatively new process technology for reinforced PU composites, combining ideas from the Spray-Up and SRIM processes. In this process, the roving is chopped into 1.0-10 mm length near the mixing head of a high pressure (RIM-like) machine. The mixed polyurethane and chopped strands are sprayed in a closed mold, which is under controlled temperature and pressure or spacing. The resulting reinforced polyurethane parts can be of very low density, depending on the allowed PU foaming.