Stochastic Modeling of Wear in Bearing in Motor Pump in Two–Tank System

This paper studies a comparative gamma and Wiener stochastic processes model. The degradation processes for data relating to fatigue phenomena, contact wear for a motor pump bearing, the Gamma process seems to be used in an exclusive way in order to model this kind of degradation [10]. However in this paper, the proposed case study presents some degradation paths that are not monotonous, i.e. the degradation pattern can show local drops/ improvements while still presenting a positive trend overall. This non-monotonic feature may be due to measurement errors or related to smaller maintenance activities. In this way, the Wiener process is selected as an appropriate model for representing non-monotonic stochastic processes. From the available data, the parameters of both processes are estimated and simulated. The two models obtained are then compared based on a model of residual life is proposed for these two processes by calculating the distribution of the time of attaining a critical threshold of contact degradation between the bearing of the motor pump and the motor axis. The practical implications of this study will be to make recommendations on the choice of a stochastic process to model the degradation of contacts.