Fatigue analysis and optimization of welds in the front frame of loaders based on multi-body dynamics and discrete element joint simulations
LIU Lizhuang
DU Jian
LIU Zhilei
BI Jiang
Abstract：[Objective]In order to solve the problem of fatigue cracking in the front frame of a loader,the joint simulation technology of multi-body dynamics and discrete element is applied to conduct weld fatigue analysis and structural optimization of the front frame based on the equivalent structural stress method.[Methods]Firstly,load spectrum collection tests were conducted for typical working conditions of V-shaped shovel loading on the user site,and the dynamic virtual load spectrums of each hinge point of that front frame were obtained.Then,six-channel unit load was applied to each hinge point of the front frame to solve the stress field results,which were superimposed with the dynamic virtual load spectrum.The fatigue simulation analysis of the front frame welds under the equivalent structural stress method was conducted.The simulation predicted three dangerous parts of the front frame,which were consistent with the after-sales fatigue cracking parts.Finally,the structural optimization of the faulty parts was carried out.[Results]The results show that fatigue life of the front frame after optimization is increased by 15.6 times compared to that before optimization,and the service life is over 15 000 hours,meeting the product design requirements.
Keywords：Multi-body dynamicsDiscrete elementJoint simulationEquivalent structural stress methodDynamic virtual load spectrumFatigue life
Publication Date：2026-03-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 114-121 )