Minimum Load-self-aligning ball bearing
In order to keep bearings working in a good condition, a minimum load must be imposed on bearings, particularly on bearings working at high speeds, high accelerations, or with the load direction changing frequently, because under these working conditions, inertial force of balls and cage and lubricant friction will have bad influence on the rotation of bearings, and detrimental sliding movement may be caused.
The minimum axial load of a self-aligning ball bearing can be obtained from
Fmin = 0.01C0
where
C0-kN Basic static load rating
When bearings are started at low ambient temperatures or in the condition where the viscosity of lubricant is very high, a larger minimum load probably is needed. Usually, the weight of bearing supporting parts plus the load on the bearing have been over the minimum load. If the weight can’t be up to the required minimum load, then extra radial load must be imposed on this type of bearing in order to meet the requirement of minimum load, e.g. increase the tension for driving belt, or other similar methods.