The spindle system is the key component of the CNC (computer numerical control) grinding machine. In order to explore the factors affecting the reliability of the CNC grinding machine spindle system and find out measures to improve the reliability of the CNC grinding machine, this paper proposed a reliability evaluation algorithm based on fault data. Five common distribution functions are used to establish the mathematical model of the time between failures. After parameter estimation, fitting test, and optimal model selection, the distribution model of the spindle system is finally determined. Monte Carlo method is used to verify the accuracy of the distribution model, and the mean time between failures (MTBF) of the spindle system is calculated. At the same time, according to the fault data, the failure mode effects and criticality analysis (FMECA) and fault tree analysis (FTA) are used to find out the key fault factors, and the corresponding improvement measures are put forward. Finally, the characteristics and application of the five distribution models are discussed. The above analysis methods have been effectively applied in the project and are one reference for the reliability evaluation and redesign of other electromechanical products.

主轴系统是CNC（计算机数控）磨床的关键部件。为探究影响数控磨床主轴系统可靠性的因素，找出提高数控磨床可靠性的措施，提出一种基于故障数据的可靠性评估算法。五个常见的分布函数用于建立故障间隔时间的数学模型。经过参数估计、拟合检验和最优模型选择，最终确定主轴系统的分布模型。采用蒙特卡罗方法验证分布模型的准确性，计算主轴系统的平均故障间隔时间（MTBF）。同时，根据故障数据，采用失效模式效应和临界分析（FMECA）和故障树分析（FTA）找出关键故障因素，并提出相应的改进措施。最后讨论了五种分布模型的特点和应用。上述分析方法在本项目中得到了有效的应用，为其他机电产品的可靠性评估和重新设计提供了参考。