Preventive spare parts supply strategy for large-scale equipment based on performance degradation

Timely replacement of spare parts can improve the reliability of large-scale equipment operation and is the critical link of preventive maintenance. This paper studies how to reasonably formulate spare parts supply strategy in large-scale equipment maintenance. Given the shortcomings of the conventional fixed cycle replacement method of equipment spare parts, a spare parts replacement method based on large-scale equipment performance degradation is proposed. The proposed method can shorten downtime and avoid waste. Firstly, by analyzing the large-scale equipment’s performance state characteristics, the performance evaluation model of the equipment is established using the interval evidential reasoning approach, and the envelope of performance degradation can be obtained. Weibull distribution is used to fit the performance degradation envelope, and the bisection method and maximum likelihood estimation method are combined to identify the model parameters. The health degree envelope of large-scale equipment performance is obtained. Then, the number of spare parts required is calculated based on health degree expectation. Considering the time required for ordering and transporting spare parts, the spare parts ordering strategy is formulated under the condition of large-scale equipment working simultaneously. Finally, the proposed method is applied to a type of large-scale equipment to verify the effectiveness of the proposed method.