Preventive maintenance policy optimization for a weighted k-out-of-n: G system using the survival signature

•A weighted k-out-of-n system consisting of critical components with high weight and other low-weight ones is studied.•The maintenance policy considers the number of failed critical components and the total weight of working components.•The expected cost per renewal cycle and system availability are analyzed based on survival signature.•The PM cycle and inspection period are optimized under the minimal expected cost rate or maximal availability. This paper presents a novel preventive maintenance (PM) policy for a weighted k-out-of-n: G system. The system consists of critical components with high weight and other low-weight components, while the critical ones significantly impact the system's total weight. The lifetime distribution of critical and other components follows the Weibull distribution with different shape and scale parameters. Different maintenance actions are performed on the component according to the number of failed critical components and the total weight of the working components. The expected cost per renewal cycle and system availability are analyzed based on survival signature. The optimal PM cycle and the inspection period are derived by minimizing the expected cost per renewal cycle or maximizing availability. Finally, the effectiveness of the presented strategy is illustrated by a numerical case.