Bearing speed factor (n·dm) calculator

Speed factor for grease and oil selection.

Calculating…

How it's calculated

dm = (d + D) ÷ 2 Speed factor = n × dm

Lubricant makers give a maximum speed factor for each grease, and viscosity charts use it to choose a base oil. Compare the result with the n·dm (or n·dm) limit on your grease datasheet. High-speed spindles often need special greases or oil lubrication.