Design of an energy efficient cylindrical roller bearing

In this study, the roller and ring raceway profiles of a cylindrical roller bearing (CRB) are designed. Starting from an initial design (i.e., an existing CRB, named NJ 309 EP4), it is intended to minimize the friction moment without sacrificing the fatigue life to have an energy efficient roller bearing. The crown heights in the roller profile, and the radius of the raceway camber profile are selected as design variables. Finite element models are developed for friction moment and fatigue life estimation using ANSYS software. Various combinations of the crown height and the radius of the raceway camber profile are evaluated, and the combination leading to minimum friction moment without sacrificing the fatigue life is obtained (i.e., a redesigned CRB is obtained). Friction moment tests and fatigue tests are conducted on the redesigned CRB (named NJ 309 OP). When the test results of the existing and redesigned bearings are compared, it is found that the friction moment of the redesigned bearing is 29% lower than that of the existing bearing, while the L-10 fatigue life being only 3% smaller. When the test results are evaluated statistically, it is concluded that the difference between the friction moment test results of the existing and redesigned bearings is statistically significant, whereas the difference between the fatigue test results of the existing and redesigned bearings is statistically insignificant.