The Structure Finite Element Analysis And Ptimization Of The Rear Frame Of LG953 Wheel Loader

Loader is a kind of engineering machine with the features of simple and convenient maneuverability. It is widely applied to the diggings and construction place. The application of loader will improve the work efficiency and avoid the waste of manpower and material resources. In recent years, many research organizations in our country have been doing some research on engineering machine, especially on loader and grab, in order to enhance the performance and the quality of these machines. Although we have made progress, there is a technology wide gap between our institute and aboard institute on study level. Therefore, in order to develop engineering construction equipments which are more economical and more efficient, it is necessary to synthetically study the structure of loader's frame. The aim is to work out the computing analysis which is the basis of designing machines.The rear frame is a pivotal part of loader, the designing level of the rear frame affects capability of the rear frame and then the loader such as strength, stiffness, reliability, economy and so on. Finite element analysis and optimization are modem design methods; the stress and strain of the rear frame in each work condition are obtained by the finite element analysis of the rear frame, and then the optimization improves the structure and capability of the products. So the finite element analysis and optimization play important roles in the design of the loader. This paper's object is LG953 wheel loader made by Shandong Lingong Construction Machinery Co., LTD. This paper analyzes the structural characteristic of this loader and mechanical characteristic after fully studying on the constitution of this wheel loader and the operation conditions. And the result of these MSC.Patran offers definite reference on the aspect of the schematic design.The finite element method is used more and more in the field of structural analysis. There are 7 kinds of structural analysis in the MSC.Patran. The displacement can be calculated directly, but strain and stress need to be deduced.The static strength analysis block of MSC.Patran can calculate the displacement,strength and strain under the fixed load.First, ascertain three typical operating conditions of rear frame: picking the normal load,traction partial set and dig up the partial support, and three typical operating condition for the numerical analysis,in order to provide rear frame structure's condition for the finite element analysis and optimization.Second,to establish the finite element analysis model of the primary structure.Using 3D design software to found solid model of the rear frame of the LG953 wheel loader,and import MSC.Patran software to carry out static strength analysis. Under the symmetry horizontal force and vertical force combined operating mode, the forces of each hinge joint can be calculated. According with the results the boundary condition and displacement constraint should be put on the finite element model.Determine the stress concentration position of every working condition ,moreover to preliminary determine the dangerous section and the reason of distortion.Last, based on the results above, the initial structure optimization of the rear frame in the shape and layout makes the distribution of stress and strain mores reasonable.The analysis results show us the following: It is feasible to analyze the static strength of rear frame by using MSC.PATRAN. The static analysis obtains the stress and distortion of one operation model, and it can not analysis the continuous work model. There are inequality stress at different area. It shows that this structure need to be improved after studying.