随机载荷下滚动轴承系统疲劳可靠性分析

传统的轴承疲劳寿命可靠性研究主要是在稳定载荷条件下对单个轴承寿命可靠度的研究。基于概率Miner累积损伤理论,推导随机载荷下滚动轴承的疲劳寿命及可靠性计算公式,并针对滚动轴承系统阐述随机载荷下各轴承的失效相关机理。根据载荷离散化思想,运用随机事件的全概率公式,推导随机载荷下滚动轴承系统的疲劳可靠度计算公式。该公式考虑了系统各轴承的失效相关性,可更客观地描述系统寿命与各设计参数的内在关系。算例以并联行星齿轮轴承系统为分析对象,运用随机载荷下滚动轴承系统的疲劳可靠度公式得到合理结果。新模型与方法可为滚动轴承系统寿命评估与可靠性分析提供理论依据。

Reliability Analysis for Rolling Bearing Systems under Random Load

The traditional studies on fatigue reliability of bearings mainly focus on the single bearing under the steady load.Based on probabilistic Miner’s cumulative damage theory,calculation formulae of fatigue life and reliability of the rolling bearing under the random load were derived and the failure dependence mechanism of the rolling bearing system was discussed.Further more,the calculation formulae of fatigue life and reliability of the rolling bearing system under the random load were derived based on the load discretization idea and the total probability formula,by which relationships between fatigue life and design variables could be depicted objectively because the failure dependence was considered.An example was given to verify the new model and method,in which the rolling bearing system of the parallel planetary gears was studied.The new model and method can provide theoretical basis for life evaluation and reliability analysis for rolling bearing systems.