High quality screw and barrel for plastic injection molding machine Diameter 90mm Min.Order 1 set Materials 38CrMoAIA GH113 SKD61 Discount Available Application PVC.PMMA.ABS 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 Technological Parameter Roughness Ra 0.4um Hardness of Quenching and Tempering HB 240-280 ...