Finite element analysis of excavator mechanical behavior and boom structure optimization

Abstract

The mechanical behavior analysis of the excavator and structure optimization of the excavator boom are conducted in this paper. By incorporating the local coordinate system established on each excavator component into the predefined global coordinate system, a parametric finite element model (FEM) of the whole excavator is developed first. Three-dimensional (3D) 20-node high-order solid brick element is used for structure discretization. Multipoint constraint element and link element are applied to simulate the telescopic behavior of the hydraulic cylinder, and the shaft-through method is developed for the numerical analysis of the pin connections of the excavator components. Given the whole FEM of the excavator, the boundary constraints can be established accurately according to the actual working condition. Then stress test experiments are subsequently implemented to verify the effectiveness of the proposed FEM, and the results show that the numerical results from the proposed FEM are in good agreement with experiment results. Lastly based on the validated FEM, the structure optimization of the excavator boom is conducted to improve the mechanical properties. The numerical analysis results show that the load bearing capacity of the boom can be improved effectively through the structure optimization.