基于三阶段时间延迟模型的设备预防维修策略

Preventive maintenance plan of equipment based on three-stage time delay model

针对设备劣化过程中出现多种非正常状态的问题,提出基于三阶段时间延迟理论的设备维修模型.首先,设备从缺陷到故障的过程并不只服从同一分布,因此,基于三阶段时间延迟模型,将设备故障分为初始缺陷、严重缺陷和故障3个状态,不同阶段定义不同的分布函数以模拟设备的劣化过程;其次,分析设备缺陷、故障发生的时刻与阈值时间点之间的关系,对维修情况进行分类,建立维修总期望费用模型,以单位时间维修费用最小为决策目标,求解出最佳预防维修周期时间和最佳阈值时间;最后,利用遗传算法求解数学模型,通过算例分析验证模型的有效性.所提出方法有助于企业根据维修计划定期进行预防维修检测,根据不同情况对设备出现的初始缺陷状态和严重缺陷状态进行预防维修.

Aiming at the problem of that many abnormal conditions may occur in the process of equipment deterioration,a maintenance model based on the three-stage time delay theory is proposed.Firstly,because the process from equipment defect to failure does not obey the same distribution,based on the three-stage time delay model,the health status of the equipment can be classified to original defect,serious defect and failure.Different distribution functions are defined at different stages to simulate the deterioration process of the equipment.Then,the relationship between the time of equipment defect and failure and the threshold time point is analyzed,and the maintenance situation is classified.The model with the lowest maintenance cost per unit time is established to find out the best preventive maintenance cycle time and the optimal threshold time.Finally,the genetic algorithm is used to solve the proposed model.The effectiveness of the model is verified by a case.It is helpful for enterprises to carry out preventive maintenance inspection regularly according to the maintenance plan,and to prevent and repair the initial defect state and serious defect state of the equipment according to different conditions.