... plastic film as HDPE,LDPEand LLDPE film blowing machine is suitable for blowing the plastic film as HDPE, LDPE and LLDPE,which ... The screw stem and cylinder are made of 38CrMoAlA, a high quality alloy steel after fine finishing and nitrogenizing treatment, which has ... high hardness, strong resistance to corrosion, durable service.2. The ...