Equivalent Dynamic (Static) Load-Needle
In order to maintain bearings working in a good condition, a minimum load must be imposed on bearings, particularly on bearings working at high speeds, with 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 load of a needle roller bearing can be obtained from.：
Fmin = 0.02C
C-Basic dynamic loading rating, N