Abstract: To improve the life of mechanical product, a mathematical model of multi-variables dynamic equilibrium design is constructed based on effective working-age estimation, which uses to solve the problems of the different components life estimation leading to products failure. A multi-variables dynamic equilibrium design optimization method is put forward based on the analysis and measurement of effective working-age of component. Based on the mathematical model the Pareto set for the multi-objective optimization problem is obtained using multi-objective algorithm. The optimal preventive maintenance schedules optimize the failure rate of components to be the same as the design required by replacing or maintaining the components before it fails. It minimizes the total cost of preventive maintenance schedule and the system failure rate of the mechanical product. The efficiency and effectiveness of the proposed method are illustrated by multi-variables dynamic equilibrium design of turbine inflation host machine of large air separation plants.

Key words: Effective working-age, Equilibrium design, Multi-variables dynamic equilibrium, Preventive maintenance