数控机床最小维修的全寿命周期可靠性评估

摘要： 基于叠加的对数线性过程(S LLP)，提出了多台数控机床在最小维修条件下的全寿命周期可靠性评估方法，建立了包含早期故障期和耗损故障期的浴盆曲线模型，定量分析了早期故障期的持续时间，给出了模型参数和可靠性指标的极大似然点估计和区间估计；同时，以多台数控机床现场故障截尾数据为例对模型进行验证.AIC值和拟合优度计算结果表明，S LLP模型优于叠加幂律过程模型，适用于数控机床的全寿命周期可靠性评估.

Whole Lifecycle Reliability Assessment of Multiple NC Machine Tools with Minimal Repair

Abstract： Based on superposed log linear process (S LLP), a whole lifecycle reliability assessment method for multiple numerically controlled (NC) machine tools with minimal repair was proposed. A bathtub curve model, which includes early failure period and wear failure period, was presented. The lasting time of early failure period was quantitatively analyzed, and the point maximum likelihood and interval estimators of model parameters and reliability indices were given. An example of real data with failure truncation from multi NC machine tools was taken to prove the proposed method. The results of AIC and goodness of fit show that the S LLP model is better than that of the superposed power law process model, which is suitable for whole lifecycle reliability assessment of NC machine tools.