剪叉式高空作业平台剪叉臂疲劳寿命分析及预测

Fatigue Life Analysis and Forecast of Scissors Arms in Scissors Aerial Work Platform

疲劳破坏是剪叉式高空作业平台剪叉臂的主要失效形式之一。用有限元分析软件建立剪叉臂的有限元模型,对其进行静力强度分析,得出剪叉臂在服役中的应力集中区域,再通过设置监测点测试剪叉臂不同位置处的应力状态。结果表明,在剪叉平台开始上升的初始时刻,剪叉臂最大应力发生在靠近油缸支耳下端铰接孔处,说明升降液压缸的驱动力对剪叉臂强度影响很大,且测试结果与仿真结果具有较好的一致性。通过名义应力法并结合材料的疲劳寿命曲线,对剪叉臂结构的疲劳寿命进行预测,为剪叉式高空作业平台的可靠性设计和结构优化提供依据。

Fatigue destruction is the main way for scissors arms to lose effectiveness in the scissors aerial work platform in the actual situation. Through finite element modeling of scissors arms estab- lished by ANSYS and static strength analysis, the region of stress concentration of scissors arms has been concluded. Stress condition of differem locations in scissors structure has been found by setting mo nitoring sites. It has been showed that the stress condition of the ini tial position of scissors arms is the biggest, and the maximum stress location lies in the hinge hole of legs of lifting cylinder at the boltom of the scissors arms, which indicates the driving force of lifting cylin der has a great impact on the intensity of scissors arms. Moreover, the test results are in accord with the stimulation result. Using nomi nal stress method, fatigue life analysis of scissors arms in scissors aerial work platform in ANSYS, the fatigue life can be predicted,which will provide the reliability design and structure perfection of scissors aerial work platform with proof and evidence. The fact that the fatigue life of scissors arms can be predicted by using nominal stress method and fatigue life curves of scissors arms in scissors aerial work platform, provides proof and evidence for the reliability design and structure optinqization of scissors aerial work platform.