Raw material：45 or S45C

Using a tube as a blank to for machining,External spline machined by spline hobbing and spline rolling process, other feature machined by turning,grinding and milling process

Heat treatment-1：quenching and tempering to HRC 23~28

Heat treatment-2：induction harden for three spline area to achieve HV600~780

Hardened depth：0.3~0.8 mm.

Tolerance requirements on outer diameter：18 micron

Tolerance requirements on inner diameter：25 micron

Roughness requirements：Ra0.4