A delay-time model for inspector team assignment and non-periodic inspection intervals

Abstract

Maintenance models based on delay-time have been extensively used in industry. However, some models still impose strong assumptions, e.g., most models do not pay attention on determining who is responsible for performing maintenance actions. Even when models do consider this, decisions regarding the moment for these actions and who is responsible for them are typically separately optimized. This paper sets out to tackle the problem of optimizing the moments for maintenance actions and the assignment of inspection teams responsible for each task, such that both decisions are jointly optimized. Thus, we propose a hybrid policy that combines inspections and age-based replacement. Due to the complexity of the problem, we propose an Adaptive Simulated Annealing algorithm, which presents percentages of optimization of up to 4.4% when compared to a general “black-box” algorithm. Our numerical results indicate that neglecting to whom the inspection would be assigned could generate worse solutions. Finally, we developed an user-friendly online app for assessing the cost-rate of the policy.

Graphical abstract

Keywords

maintenance / inspector team assignment / aperiodic inspections / simulated annealing / imperfect inspections

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