Mitutoyo SJ-210 - Evaluating Based on ANSI

No. 99MBB122A
18-6
18.1.5 Evaluating based on ANSI
Shown below are the standard cut-off values and evaluation lengths for evaluation based
on ANSI.
■ Standard cut-off lengths and evaluation lengths for measuring roughness parameters from periodic profiles
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Sm Range Cut-off value (λc) Evaluation length (ℓn)
0.013 (0.0005) < Sm ≤ 0.04 (0.0016) mm (in) 0.08 (0.003) mm (in) 0.4 (0.016) mm (in)
0.04 (0.0016) < Sm ≤ 0.13 (0.005) mm (in) 0.25 (0.01) mm (in) 1.25 (0.05) mm (in)
0.13 (0.005) < Sm ≤ 0.4 (0.016) mm (in) 0.8 (0.03) mm (in) 4 (0.16) mm (in)
0.4 (0.016) < Sm ≤ 1.3 (0.05) mm (in)
2.5 (0.1)
mm (in) 12.5 (0.5) mm (in)
To select a cut-off value from the previous table, you must estimate the Sm value from an
unfiltered-profile chart.
■ Standard cut-off lengths and evaluation lengths for measuring roughness parameters from non-periodic
profiles
Ra Range Cut-off value (λc) Evaluation length (ℓn)
Ra ≤ 0.02 (0.8) µm (µin) 0.08 (0.003) mm (in) 0.4 (0.016) mm (in)
0.02 (0.8) < Ra ≤ 0.10 (4) µm (µin) 0.25 (0.01) mm (in) 1.25 (0.05) mm (in)
0.10 (4) < Ra ≤ 2.0 (80) µm (µin) 0.8 (0.03) mm (in) 4 (0.16) mm (in)
2.0 (80) < Ra ≤ 10.0 (400) µm (µin) 2.5 (0.1) mm (in) 12.5 (0.5) mm (in)