Optimal Minimal Maintenance of Multistage Degraded System with Repairs

Abstract A Markov model is considered to calculate the steady state availability of a system which may adopt several stages of degradation and is subject to random failures at each stage of degradation. Minimal maintenance and partial repairs restore the system to the previous degraded stage and to the operational stage just before failure, respectively. Overhaul repair returns the system to “as good as new” after degradation failure. Finally, the mean time to minimal maintenance minimizing the unavailability is determined.