Oil film stiffness calculation of high speed angular contact ball bearings considering spinning

Spinning exists in high-speed transmission support bearings, it can affect oil film thickness of a bearing. The calculation formulas for oil film stiffness of an angular contact ball bearing considering spinning was deduced based on the elastohydrodynamic lubrication (EHL) theory and the method for calculating attitude angle with Darren Bell theory, considering varying of the minimum oil film thickness on the contact points between balls and raceways when spinning exists both at inner and outer raceways. An example was calculated with the derived formulas and the result was compared with that calculated using the minimum oil film thickness empirical formulas proposed by Hamrock-Dowson without considering spinning. The calculation results showed that the spinning angular velocity increases with increase in the rotating speed but decreases with increase in load, the effect of the radial load on spinning is larger and the effect of the axial load is less; the minimum oil film thickness considering spinning is smaller and the oil film stiffness is bigger due to the effects of sliding velocity after considering spinning; so, it is necessary to consider the impact of spinning on bearing stiffness when calculating high-speed transmission shafting vibrations.