Optimal Group Replacement Policy for Multi-Component Systems with Weibull Lifetime Distributions  
Author Ruey-Huei Yeh


Co-Author(s) Chuan-Wen Chiu; Ya-Han Yu; Wen-Liang Chang


Abstract This paper investigates the replacement policies for a system with multiple components. Two possible structures of these components in a system are considered -- series and parallel. For both structures, when a component fails, minimal repair is performed to rectify the failed component. Due to the inevitable deterioration, a component may fail more frequently as its age or usage increases. In practice, one way to reduce the number of failures is replacing the components at certain ages preventively. However, when a replacement action is performed, it may incur not only a replacement cost and the system downtime cost but also a setup cost, if a technician or a professional team is required. Under this situation, replacing a group of components at the same time may reduce the number of setups and system downtimes, especially when the components are connected in series. In this paper, the cost models for both series and parallel systems are constructed. Based on the models, the optimal grouping policy and the optimal replacement time of each group are derived such that the expected long-run cost rate is minimized. Furthermore, the impacts of the downtime cost for both series and parallel systems are analyzed through numerical examples.


Keywords Group replacement policy; Group replacement time; Series system; Parallel system
    Article #:  22045
Proceedings of the 22nd ISSAT International Conference on Reliability and Quality in Design
August 4-6, 2016 - Los Angeles, California, U.S.A.