High corrosion resistance single screw barrel for extruder plastic Diameter 55mm-75mm Min.Order 1 set Material 38CrMoAIA 42CrMo(JIS SCM440) 9Cr18MoV CW6Mo5Cr4V2 SKD61 Discount Available Application PP,PE sheet,profile,pipe Payment Term T/T, L/C Technical Process 1.Rough Machining 2.Quenching and Tempering 3.Finish Machining 4.Nitriding 5.Spraying and welding with alloy power 6.Screw polishing ...