Technical Paremeters for parallel twin screw and barrel Steel Material 38GrMoAlA,42GrMo Hardness after hardening &tempering HB:280-320 Hardness &Tempering time 72 hours Nitrided hardness HV:850-1000 Nitrided time 120hours Depth of nitriding case 0.50-0.80mm Nitrided Brittleness less than grade 2 Surface Roughness Ra:0.4 surface hardness of chromium- plating after Nitriding >HV900 Depth of chromium -plating 0.025-0.10mm Alloy Hardness…