Domestic And Foreign-made CNC Lathe Reliability Contrast Analysis

1. INTRODUCTIONEnhancing NC lathe reliability has become the key of survival and development for Numerical control lathe manufacture enterprise. Today machine tool market compete drastically, it is higher reliability NC lathe that can get consumer favor. Whether the numerical control lathe reliably does become user purchase the important standard. In recent years our country numerical control lathe had the quick development in the production and the application domain, but compared with the industry developed country, still had the big disparity. Therefore, quickly increasing the reliability of Domestic NC lathe is a problem for urgently needing the solution.United the national 863 topic further more, this thesis has carried contrast analysis on reliability of the national numerical control lathe and the some country produced numerical control lathe, that can represent the international advanced level on the produced numerical control lathe.2. RELIABILITY MODEL ANALYSISThis thesis begun with the failure data of the national numerical control lathe and overseas produced the numerical control lathe, started to their reliability analysis.Reliability model establishment mainly have following five steps: reliability data gather; data preliminary analysis; model choice; model parameter estimate and model supposition examination. Among them, in the model parameter estimation, this thesis applied the linear return method and the least squares estimation method; in the model supposition examination, this thesis has applied the linear relevant examination, applied the d test to carry on the examination to the distribution. The analysis has obtained the failure data of the domestic and foreign numerical control lathes to conform to the Weibull distribution, and has obtained their probability density function f(t) and distribution function F(t) of the mean time between failure.