Joint Optimization of Replacement and Spare Parts Ordering with Dual Sourcing

Abstract

To optimize the joint decisions of equipment maintenance and spare parts ordering with dual sourcing, a joint policy is proposed for a multi-unit parallel manufacturing system. The degradation trajectories of components are described by the Poisson process. The joint decisions are modeled according to the Markov decision process. Based on components and inventory status, the transition probability of a system is formulated. The value iteration algorithm is applied to obtain the optimal maintenance and spare parts ordering policy to minimize the average total cost of the system. Furthermore, to shorten the computation time, a heuristic strategy is developed according to the principle of sequential optimization. Numerical experiments with a two-component system are conducted to analyze the decision difference between the heuristic strategy and the optimal strategy. The sensitivity analysis shows that compared with the optimal strategy, the heuristic strategy can reduce the computation time when the total cost increases by no more than 5%.

Keywords

• preventive maintenance
• spare parts ordering
• dual sourcing
• joint optimization
• heuristic strategy