Document Type : Research Paper


Aerospace Research Institute, Ministry of Science, Research and Technology, Tehran, Iran


Manufacturing systems are one of the complex systems for modelling and analysis, different types of structures may be utilized for this. Their behaviour is similar to Multi-state systems. Multi-state system configurations, possibly with load sharing and other structural dependencies are designed to provide high reliability/availability. Consequently, this scheme can help companies to improve efficiency and reduce operation cost. During operation and utilization, maintenance and part replacement contribute to keeping their performance. Decision-making about spares ordering is difficult because of the interconnection between spare parts inventory and maintenance strategy. In this paper, the characteristic parameters of spare parts inventory management and maintenance policies are jointly considered for multi-machines systems (manufacturing systems) with different types of dependencies among them (economic, load-sharing, and multi-state configuration). Two maintenance policies are considered: condition-based and preventive maintenance. The interactions among maintenance policies and spare parts management are considered for determining system cost and availability of a manufacturing system. These factors influences are investigated. load sharing factor and ordering time are more important and their influence are higher then others.

Graphical Abstract

Reliability, availability and maintainability modelling of multi-state systems with load-sharing structure


Main Subjects