数控车床故障传播机理分析

Failure propagation mechanism analysis of CNC lathe

为探讨数控车床故障传播机理,即识别系统关键节点与关键故障传播路径,基于数控车床故障数据,应用有向图理论、集成决策实验室分析(DEMATEL)和解释结构模型(ISM)方法构建数控车床分层故障传播有向图模型;基于故障传播概率、边介数两指标定义故障传播强度表征故障传播行为;提出结合系统分层故障传播有向图模型和故障传播强度的数控车床故障传播机理分析方法.分析结果表明:系统分层故障传播有向图模型实现了系统层级分解,简化了故障传播分析过程,为关键路径识别奠定了基础;将故障传播强度作为关键路径识别的依据,避免了传统分析方法基于单一指标描述数控车床故障传播行为而产生的偏差,实现了准确定位故障源,准确识别系统关键路径.所提方法有助于系统故障诊断与维护.

To study the failure propagation mechanism of CNC lathe,i.e.,to identify the critical nodes and critical failure propagation path of system,by applying the digraph theory,integrating DEMATEL with ISM method,the hierarchy failure propagation digraph model of CNC lathe is constructed based on failure data. A failure propagation strength is defined based on failure propagation probability and edge betweenness to characterize failure propagation behavior,and then a failure propagation mechanism analysis method for CNC lathe according to the hierarchy failure propagation digraph model and the failure propagation strength is proposed. The analysis result shows that the system hierarchy failure propagation digraph model achieves the system hierarchy decomposition,and simplifies the failure propagation analysis process,which lays a foundation for the critical path identification. Regarding the failure propagation strength as criterion of critical path identification avoids the deviation arose from the traditional analysis method based on single index to describe the failure propagation behavior of CNC lathe,and realizes precise failure source and system critical path identification. This helps to the system failure diagnosis and maintenance.