Proximity analysis on the life distribution functions of the high-speed rotating machine

The exponential distribution is widely used in studies of reliability engineering as a model for life, largely because of its mathematical simplicity. But a mechanical product´s life distribution is not in obedience to exponential distribution generally. To find how an exponential distribution can be applied in the high-speed rotating machine´s life study, which has the characteristic of wear and tear, the proximity analysis among the life distribution functions is studied in this paper. The study on proximity analysis bridges the parameters between exponential distribution and non exponential distribution (Weibull and lognormal distributions), and then the crucial parameter and its range which affect the proximity of Weibull and lognormal distribution to exponential distribution are obtained respectively. According to the life test data, the restriction to use exponential distribution to predict the life of the high-speed rotating machine is found finally. This outcome improved efficiency during the study on the high-speed rotating machine reliability, so its significance on engineering application is distinct.