Subsystems Risk Assessment of the CNC Machine Tools

The subsystems risk assessment is an important problem for reliability study of the CNC machine tools. A novel method based on reliability different function for assessing the subsystem risk was proposed. Firstly, failure data and subsystem could be described. Secondly, the subsystem reliability of the CNC machine tools was estimated using the mean rank method, since the failure data of subsystem is the less. At the same time, Weibull distribution parameters were estimated using the Maximum Likelihood Estimation (MLE) .Thirdly, the reliability different function set of the CNC machine tools was attained by assuming that each subsystem was between absolutely reliable and non-absolutely reliable, and the comparative analysis of subsystem reliability was conducted for assessing the subsystems risk. Finally, a case example analysis proved that the proposed method could assess subsystem risk of the CNC machine tools rapidly and accurately.