screw and barrel for extruder 

Product Description  Technical Parameters for extruder screw and barrel Steel Material 38CrMoAlA,42CrMo 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…