含裂纹装载机动臂的剩余寿命预测

Residual Life Prediction Method of Loading Boom Based on Fatigue Crack

工程机械的结构件在生产中大多承受非对称变幅的载荷且在多年后会现疲劳裂纹,针对这个特点本文以断裂力学理论为基础,并运用Gerber曲线和RMS模型修正非对称变幅载荷谱,推导出一种针对非对称变幅载荷下结构件的剩余寿命的计算方法。本文将装载机动臂回收件为研究对象,结合多体动力学和有限元分析得到动臂危险点的载荷历程,并根据危险点处的载荷采用本文提出的计算方法进行寿命预测。

Most of the structural parts of the construction machinery are beared unsymmetrical and variable amplitude load in production and the fatigue cracks will occur after years.For this feature,the theory of fracture mechanics are used as the theoretical basis. The calculation method methods are proposed to solve the unsymmetrical and variable amplitude load spectrum which Gerber curve and RMS models to correct the unsymmetrical and variable amplitude load spectrum. In this paper,the loader boom recycled are taken as the research object. We combined with multi-body dynamics and finite element analysis are used to get the load spectrum of the dangerous point of the boom,and predict the life according to the load spectrum at the risk point using the calculation method proposed in this paper.