基于不完全维护的劣化系统分阶段顺序预防维护策略

Phasic Sequential Preventive Maintenance Policy Based on Imperfect Maintenance for Deteriorating Systems

多数系统维护之后的状态介于'全新'和'如旧'之间。基于不完全维护理论,引入考虑设备工龄和维护成本的改善因子,结合维护活动的实际情况,提出分阶段顺序维护的概念。以设备整个维修周期内的成本率最低为优化目标,建立两种顺序预防维护模型,即一般顺序预防维护模型和分阶段顺序预防维护模型(模型I和模型II),得到系统最优维护时间间隔和在全寿命周期内执行预防维护的次数,通过数值验证对各自模型的特点和有效性进行讨论。结果表明,分阶段顺序预防维护模型在不明显增加系统维护成本的前提下,既可以很好地适应劣化系统失效率随工龄增加而增长的特点,又能够贴近维修生产实践,使其在寻求最优维护策略方面兼具更好的经济性和可行性。

The state of most systems after maintenance is somewhere between as good as new and as bad as old.Based on the imperfect maintenance theory,a new improvement factor considering the equipment working age and the maintenance cost is introduced.In order to make the policy more suitable in operation,the concept of phasic sequential preventive maintenance is put forward.By minimizing the cost rate of the maintenance in the life cycle of the system,two sequential preventive maintenance models are proposed,the general sequential one and the phasic sequential one.The optimal preventive maintenance intervals and the number of preventive maintenance activities are obtained from the model.The numerical results show that the phasic sequential preventive maintenance policy is more operable in the actual maintenance activities and more appropriate to the properties of the deteriorating systems.Compared with the general model,the phasic one achieves a better economical efficiency and operability at the same maintenance cost.