Maintenance Decision Model Of Long Storage Products Based On Failure Risk

Long-storage product is a complex system,which could be divided into components and systems.In the long-term storage process of long-storage products,due to various factors,the performance will degrade and the failures will occur.These failures may cause failure risk consequences such as product could not work properly or even catastrophic accidents.Therefore,in the process of long-term storage of products,it is of great significance to formulate corresponding inspection and maintenance strategies to ensure the reliability and safety of long-storage products.Taking into account the relevant characteristics of the inspection and maintenance of long-storage products,the following issues are studied in this paper:Firstly,research on maintenance decision model framework of long-storage products based on failure risk.Aiming at the relevant characteristics of long-storage products,a four-aspect maintenance decision-making model framework is established for longstorage product based on failure risk: the first one is the selection of key subsystems based on failure risk assessment,then is the sequential inspection model of components based on system failure risk,and the component-level maintenance decision model considering the constraints of failure risk,and the last aspect is the system-level maintenance decision model considering the failure risk constraint.This section will provide methodological guidance for developing an inspection and maintenance strategy for long-storage products.Secondly,research on sequential inspection model for components of long-storage product based on failure risk.Firstly,the reliability constraint value of the component is determined according to the failure risk constraint of the system and the component importance.Then the analytical expression of the real-time reliability distribution of the component is obtained by use of the Wiener process and the first-hitting time theory,and the unknown parameters of the model will be adaptively estimated once the new degradation information is available.Thirdly,a kind of optimization method is proposed to determine the sequential inspection interval to satisfy the requirements of the real-time reliability at the certain time.Finally,the effectiveness of the model and algorithm is verified by an example of a simple series-parallel system and the gyroscope.Thirdly,research on maintenance decision model for components of long-storage product considering failure risk constraints.Firstly,a maintenance decision model is established for individual components based on the sequential inspection model,of which the cost of inspection and maintenance is taken as the optimization goal,and theory of the update process is used.Then the real-time reliability requirements and preventive maintenance thresholds of the components are optimized by using the simulation method.Thirdly,the retrospective evaluation of failure risk and iterative analysis are carried out on the optimization results of the components.Finally,the model is verified by an example of the gyroscope.Finally,research on maintenance decision model of long-storage system considering failure risk constraint.Due to the maintenance correlation between system components,the inspection and maintenance process of the system is analyzed firstly in this section,and the system update cycle and maintenance strategy are determined based on the maintenance decision model of components.Then based on the theory of the update process,the minimum cost of inspection and maintenance is taken as the optimization goal,the maintenance optimization objective function of the system is established,and the real-time reliability requirement and preventive maintenance threshold of each component in the system are calculated by the simulation method.Thirdly,the retrospective evaluation of failure risk and iterative analysis are carried out on the optimization results of the components.Moreover,according to the optimized value of the real-time reliability requirements of the components,a comprehensive importance of components based on failure risk is proposed and analyzed.Finally,a two-part serial system example is used to verify the effectiveness of the proposed model,and the importance of considering the failure risk constraint in the system maintenance decision is revealed.