Reliability Modeling on Time between Failures of NC Machine Tools

Abstract

A reliability modeling method is proposed based on the time between failures of NC machine tools. According to the field data of the time between failures of a certain type of NC machine tools, parameter estimation of reliability model is made by use of particle swarm optimization (PSO)-based correlation coefficient optimization method, and it is proved that time between failure of CNC machine tool obeyed mathematical model of 3-parameter Weibull distribution via hypothesis testing. This provides the basis for reliability assessment of NC machine tool as well as the development of maintenance strategy in the future. Meanwhile, it also provides a theoretical reference for the reliability prediction of the whole NC machine tool.