Reliability Modeling of CNC Machine Tool Electric Spindle Based on Environmental Factors

Accurate reliability evaluation of CNC machine tool electric spindles is often challenged by a lack of fault data. This paper proposes a novel approach using a two-parameter Weibull distribution model that integrates environmental factors to address this issue. Unlike traditional models, our method combines expert judgment and historical product data with the concept of environmental factors, providing a more robust evaluation of electric spindle reliability, especially under small sample conditions. The mean time between failures (MTBF) is used as the evaluation index, and we derive the posterior distribution of Weibull parameters using Bayesian theory. This approach allows for a comprehensive reliability model that accounts for varying operating conditions. Our results demonstrate that incorporating environmental factors leads to a more accurate and reliable assessment of CNC machine tool electric spindles, offering a new theoretical and practical basis for reliability evaluation in similar mechanical products.