Resumen
Since the designed bearing’s reliability of 90% was determined in a lab environment, it does
not represent the actual used environment. In this paper, a new methodology to determine the actual
reliability that corresponds to the use conditions is o ered. This new method is based on the standard
method used to select the ball bearing. The proposed method is based on the two parameters of
Weibull distribution, where the shape ( ) and scale ( ) parameters are both determined from the
Hertz contact stresses values, which are generated under the surface of the motionless outer race,
and by the forces transmitted between the ball and the outer race. Therefore, the derived reliability is
di erent from the 90% index o ered by manufacturers.