Technical parameter:
Diameter of screw: φ45-φ200
L/D ratio: 16-35
Hardness after hardening and tempering: HB280-320
Nitriding hardness: 950-1100HV
Nitrided layer depth: 0.5-0.8mm
Nitrided brittleness: Less than grade 2
Surface roughness: Ra0.4
Linearity of screw: 0.015mm/m
Bimetallic layer depth: ≥3mm
Bimetallic hardness: HRC60-72
Hard-chrome plating hardness after nitriding: ≥950HV
Chrome-plating layer depth: 0.025~0.10mm
Material:
High-quality alloy steel
38CrMoAlA (JIS SACM645)
42CrMo (AISI 4140)
9Cr18MoV
Treatment:
Nitriding
Hard-chrome plating
Alloy powder spray welding