Die head:45# steel,hard chrome-plating. Screw: 38CrMoAl Motor, air blower, up traction unit: inverter controlled automatic SJ series co-extrusion double layer film blowing machine Co-extrusion double layerfilm blowing machine main technicalparameters: ModelSJ(50*2)-1100SJ(55*2)-1700SJ(60*2)-2000Suitable MaterialHDPE,LDPE,LLDPEScrew Diameter φ50×2φ55×2φ60×2Film Width(mm)600-1000800-15001000- ...