Technical Data

The Perfect Oilless SGO

Surface roughness

Arithmetical mean roughness (Ra) Max. height (Ry) 10-point mean roughness (Rz) Standard length of R max. Rz ℓ (mm) Triangular idication
Preferred Number Series Cut-off value
π C(mm)
Indication of Surface Texture on drawings Preferred Number Series
0.012α 0.08 도면 0.05s 0.05z 0.08 기호
0.025α 0.025 0.1s 0.1z
0.05α 0.2s 0.2z 0.25
0.1α 0.8 0.4s 0.4z
0.2α 0.8s 0.8z 0.8
0.4α 도면 1.6s 1.6z 기호
0.8α 3.2s 3.2z
1.6α 6.3s 6.3z
3.2α 2.5 도면 12.5s 12.5z 2.5 기호
6.3α 25s 25z
12.5α 8 도면 50s 50z 기호
25α 100s 100z 8
50α 도면 200s 200z ~
100α - 400s 400z -


  • The interdependence for 3 classes is not strictly enforced.
  • The evaluation lengths of Ra, Rmax and Rz: Five times the cut-off value and standard length