Slip Characteristics in Cylindrical Roller Bearings-Part III: Influence of Bearing Clearance on the Roller and Set Slip

The set and roller slip of an NU215 cylindrical roller bearing with medium clearance (MC) and tight clearance (TC) classes have been tested and compared to those of extensive clearance (EC) presented in Parts I and II of this publication. A total of two cages were tested in this part presenting the brass and polyamide single-part cages. The normal TC clearance under the tight fitting of the inner and outer rings resulted in preloading of all the rollers and hence no set slip. Under low oil flowrates, the roller experienced no slip even in the load free zone. For the MC clearance, the polyamide cage showed better behavior (less roller and rolling set slip tendency) than the brass cage contrasting the results obtained earlier under the EC clearance. It is concluded that the polyamide cage deforms under the unsymmetrical loading of the EC clearance resulting in this elevated slip however, under a more even loading in the MC clearance, its lightweight was reflected in a reduced slip behavior.