Conical twin screw barrel/Twin conical Screw Barrel/Screw Barrel Technology: 1.nitriding treatment 2.alloy coating spraying 3.heating treatment 4.screw fully hardening Used for granulation,PP, PE, PA, PC, ABS,AS etc Based Material: 38CrMoAlA, SKD61 etc. Treatment: Nitriding, Bimetallic spraying Depth of Nitrated Layer: 0.5 - 0.8 mm Hardness: 58 - 72 HRC Fragility of nitration: Less than grade1 Surface roughness: Ra 0.4um Thickness of Bimetallic layer: 2 - 4 mm We supply various types of twin screw barrel, such as tungsten carbide coated type, ni-based type, TIN coated types. If you have any inquiry, do not hesitate to inform us.