The Influence of location of balls and ball diameter difference in rolling bearings on the nonrepetitive runout (NRRO) of retainer revolution

The nonrepetitive runout (NRRO) value of retainer revolution is caused mainly by the diameter differences of balls mounted in a bearing. Additionally, when more than one ball has diameter difference, the NRRO value of retainer revolution is believed to vary with the location of balls. In this study, the authors theoretically analyzed the NRRO value of retainer revolution considering the diameter differences and location of balls mounted in a bearing. Consequently, it is clarified that the mean value of the retainer revolution component calculated in all locations of balls decreased with increasing number of balls in a rolling bearing.