plastic extrusion screw and barrel

sus screw and barrel is widely used for food machinery

Screw barrel's technician index:

a.Hardness after hardening and tempering: HB280-320 

b.Nitrided Hardness: HV850-1000

c.Nitrided case depth: 0.50-0.80mm

d.Nitrided brittleness: less than grade 2 

e.Surface roughness: Ra 0.4

f.Screw straightness: 0.015 mm

g.Surface chromium-plating's hardness after nitriding: ≥900HV

h.Chromium-plating depth: 0.025~0.10 mm

i.Alloy Hardness: HRC50-65 

j.Alloy depth: 0.8~2.0 mm