Abstract
For long-term storage systems such as rockets and missiles, most of the relevant models and algorithms for inspection and maintenance currently focus on analysis based on periodic inspection. However, considering factors such as the complexity of the degradation mechanisms of these systems, the constraints imposed by failure risk, and the uncertainty caused by environmental factors, it is preferable to dynamically determine the inspection intervals based on real-time status information. This paper investigates the issue of maintenance optimization modelling for long-term storage systems based on real-time reliability evaluation. First, the Wiener process is used to establish a performance degradation model for one critical unit of such a system, and a closed-form expression for the real-time reliability distribution is obtained by using the first-hitting-time theory. Second, sequential inspection intervals are dynamically determined by combining the real-time reliability function with a real-time reliability threshold for the system. Third, a maintenance optimization model is established for the critical unit based on update process theory. An analytical expression for the expected total cost rate is derived, and then, the real-time reliability threshold and the preventive maintenance threshold for the unit are jointly optimized by means of Monte Carlo simulation, with the lowest expected total cost rate as the optimization goal. Finally, two examples of a gyroscope and an alloy blade that are commonly used in the long-term storage systems are considered, and the validity of the proposed model is illustrated by means of a sensitivity analysis of the relevant parameters.
Highlights
For long-term storage systems such as rockets and missiles, most of the relevant models and algorithms for inspection and maintenance currently focus on analysis based on periodic inspection
This paper focuses on long-term storage systems and proposes corresponding nonperiodic inspection strategies
A long-term storage system will undergo a series of inspections I = {t, t, ⋯, t } during its life cycle, where t ∈ I is the time of the i-th inspection, and will eventually be subjected to either preventive maintenance (PM) or corrective maintenance (CM)
Summary
“Long-term storage, one-time use” systems, such as missiles and rockets, are kept in long-term storage for the majority of their lifetimes, from the factory to either use or decommissioning, and most such systems are high-value and high-risk products, and need to be maintained at a certain level of reliability during this long-term storage. The majority of existing CBM research on other products considers either a periodic inspection schedule or a fixed preventive maintenance threshold To address this gap, this paper focuses on long-term storage systems and proposes corresponding nonperiodic inspection strategies. A sequential inspection policy is used in this paper, and the relevant thresholds are optimized to improve the efficiency of inspection and maintenance for long-term storage systems. The model proposed in this paper can guarantee the safety and reliability of a long-term storage system and can improve the efficiency of inspection and maintenance and reduce maintenance costs, providing decision-making support for the development of inspection and maintenance strategies for long-term storage systems.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
