### Common Formulas for Milling Operations Speed, Feed, SFM

Milling Formulas.Speed(RPM) = (SFM x 3.82) / D.Feed(IPM) = RPM x FPT x Z. SFM (Surface Feet per Minute) = (RPM x D) / 3.82. IPT (Inches per Tooth) = (IPM / RPM) / Z. MRR (Cubic Inches per Minute) = IPM * WOC * DOC. AFPT (@ less than 1/2 dia. WOC) = IPM x sqroot of (D / WOC) HP (Horsepower Consumption) = MRR x mf. mf - steel = 1.