Technical Parameter: Size: Screw OD: Φ35mm-Φ200mm Length: ≤10000mm Barrel ID: Φ35mm-Φ200mm Depth of Nitrated Layer: 0.5-0.8mm Hardness of nitration: 900-1020Hv Fragility of nitration: Less than grade 1 Surface Hardness of Nitrated Cr coating layer: ≥950Hv Thickness of Cr-coating Layer: 0.03-0.08mm Technology: nitriding treatment, alloy coating spraying, heat-treatment Bimetallic alloy coating Use in: PP, PE, PA, PC, ABS, AS etc