基于实测载荷的挖掘机动臂精细化焊缝疲劳寿命分析  

Fatigue life analysis of fine-grained weld seam of excavator arm based on measured load

作　　者：熊敏[1] 石劲松 丁晓红[1] 刘纯琨 李官运 XIONG Min;SHI Jinsong;DING Xiaohong;LIU Chunkun;LI Guanyun(School of Mechanical Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;SANY Heavy Industry Co.,Ltd.,Kunshan 215300,China)

机构地区：[1]上海理工大学机械工程学院,上海200093 [2]三一重机有限公司,昆山215300

出　　处：《上海理工大学学报》2024年第5期502-508,555,共8页Journal of University of Shanghai For Science and Technology

基　　金：国家自然科学基金资助项目(51875380)。

摘　　要：针对挖掘机动臂疲劳失效多发于焊缝连接处的问题,建立精细化的焊缝疲劳寿命预测模型,基于实测载荷对挖掘机动臂疲劳寿命进行分析。以某特定型号的液压挖掘机动臂为分析对象,基于载荷反演技术获得挖掘机动臂在石方和土方环境作业下的铰点载荷,对动臂焊缝部位进行精细化有限元建模,结合焊缝材料的S-N曲线以及线性MineR损伤理论,分别预测动臂焊缝部位在石方和土方环境下的疲劳寿命。分析表明,焊缝部位在石方和土方环境下最低疲劳寿命分别为5.815×10^(5)和1.160×10^(6)次,此分析方法可为同类型机械焊缝结构疲劳寿命分析提供参考。To address the problem that fatigue failures of excavator movable arms mostly occured at the weld joints,a fatigue life prediction model for refined welds was established and the fatigue life of excavator movable arms was analyzed based on the measured loads.Based on the load inversion technique,the hinge point load of the arm in stone and earthwork work condition was obtained,and the finite element modeling of the movable arm weld part was refined,and the S−N curve of the weld material and linear Miner damage theory were combined to predict the fatigue life of the movable arm weld part in stone and earthwork work condition respectively.The fatigue life of the movable arm weld area under rock and earthwork conditions was predicted by combining the S−N curve of the weld material and linear Miner damage theory.The analysis shows that the minimum fatigue life of the weld part in stone and earthwork work condition is 5.815×10^(5) and 1.160×10^(6) times respectively,and the analysis method can provide reference for the fatigue life analysis of the weld structure of the same type of machinery.

关 键 词：液压挖掘机动臂 载荷反演 精细化建模 疲劳寿命分析 

分 类 号：TH122[机械工程—机械设计及理论]