plastic extrusion screw and barrel 1.Suitable plastic material:PP,PEetc. 2.Material:SACM-645,SCM440,38CrMoALA 3.high quality plastic extrusion screw and barrel Size:screw diameter ø15-ø300mmMaximum screw ... Rougness of the surface:Ra0.46.Linearity of the screw:0.015mm7.The surface hard chromium plating hardness ... alloys:0.8-2.0mm Used for granulation ,PP,PE,PA,PC,ABS,AS etcWe can manufacture various ...