Grinding Wheel Speed Calculator

Inputs

View results
Current wheel diameter — speed falls as the wheel wears smaller.
in
Wheel spindle RPM.
rpm
The maximum operating speed printed on the wheel blotter/label for THIS wheel. Enter 0 to skip the check — but the marking always governs.
rpm
OD being ground, for the speed-ratio check. 0 for surface grinding / no rotating work.
in
Workhead RPM. 0 to skip.
rpm

Results

Default result
Edit inputs
Wheel surface speed(v_s)
5,655SFM

Compare with the wheel’s rated speed class (conventional vitrified wheels are commonly rated 6,500 SFM).

Also computed

Of marked max RPMPass87%

Within the marking. As the wheel wears smaller you may raise RPM to recover surface speed — never past this marked limit.

Work surface speed(v_w)78.5SFM

Speed ratio(q)72

Inside the conventional 60–100 band for OD grinding.

v_wheel ÷ v_work; conventional OD grinding commonly runs q ≈ 60–100.

Method notes 4 notes
  • The marked maximum operating speed on the wheel is absolute — bursting speed tests sit above it by a designed margin you are never entitled to spend (ANSI B7.1 governs mounting, guarding and speed).
  • Wear math: surface speed falls linearly with diameter at fixed RPM — a 12 in wheel worn to 10 in has lost 17% of its SFM, which is why variable-speed grinders exist.
  • Burn fixes in order: raise work speed (drops q), sharpen/dress the wheel, reduce infeed — before reaching for coolant changes.
  • Ring-test wheels before mounting, use blotters and the correct flanges, and let a newly mounted wheel run a full minute behind the guard before grinding.

Powered by MachineCalcs ↗