Opportunistic maintenance for two-component series systems subject to dependent degradation and shock

• Published in: Reliability engineering & system safety Vol. 201; p. 106995
• Main Authors: Hu, Jiawen, Shen, Jingyuan, Shen, Lijuan
• Format: Journal Article
• Language: English
• Published: Barking Elsevier Ltd 01.09.2020; Elsevier BV
• Subjects: Degradation; Dependent failure modes; Economic dependence; Inspection; Inspection/replacement; Preventive maintenance; Reliability engineering; Shock; Wiener degradation process; Economic dependence; Wiener degradation process; Inspection/replacement; Dependent failure modes; Preventive maintenance
• ISSN: 0951-8320; 1879-0836
• DOI: 10.1016/j.ress.2020.106995

•An opportunistic maintenance model for systems consisting of two components is proposed.•Each component is subject to dependent degradation and fatal shock.•The closed-form of the long-term average cost is formulated based on the semi-regenerative properties. This work studies a maintenance policy for a system consisting of two independent and identical components in series, where each component is subject to dependent degradation and fatal shock. We use a Wiener process to model the degradation, and assume that the shock rate is an increasing function of the degradation level. To utilize the economic dependence between two components, we propose an inspection/replacement opportunistic maintenance (OM) policy. A replacement is carried out to the component of which the degradation exceeds a preventive maintenance (PM) threshold at an inspection, or a fatal shock occurs. Whenever a replacement is carried out, the other component will be replaced if its degradation exceeds an OM threshold. The optimal combination of the inspection interval, OM and PM thresholds are jointly determined by minimizing the long-run average cost, which is formulated based on the semi-regenerative properties of the system state. A numerical study is provided to demonstrate the maintenance policy.