Failure Rate Evaluation of CNC Machine Tools Based on G-R Curves Analysis

G-R scaling relations are commonly used on seism prediction. It´s mainly used to estimate seism activities for different spaces and time windows and also to predict the probability of seism occurrence. The variance of b-values can reflect the seism active degree of the area. The paper uses this curve to describe the relationships of failure grades and failure rates of CNC lathes which makes an attempt on reliability analysis of CNC lathes. We can draw the conclusions that b value in frequent failure time is lower than in stable failure time. The value is towards 1.0 when the reliability level of CNC lathes is highly promoted through ten years´ reliability promotion.