Research On Structure Optimization Of Loading 98T Aluminum Alloy Hopper Car Body

With the increase of coal output, the requirement of rail wagons transport efficiency was enhanced since 2000, and bran-new structure, material and design concept were employed into rail wagons in China. Recently,although new aluminum van had been gradually put on the market, there was still a big gap between our country and developed countries in terms of the vehicle’s design technique and material.This paper took advantage of large-scale finite element software ANSYS to analyze the static strength of aluminium alloy hopper car in KM98 model, then optimized the vehicle according to the stress analysis results,and conducted the fatigue life evaluation for several dangerous weld in the optimized body model.According to the coulomb friction theory,nonlinear riveting connection structure of submodel was set up in this paper, and riveting structure was also simulated with the entity unit and shell element respectively.This paper analyzed the influence on the calculation results of choosing different unit when riveting structure under shear and pull, pressure load; and made a comparison with linear model to get the stress scale factor of rivet hole, so that we can evaluated the stress of corresponding position on hopper car model during the calculation of static strength.On the basis of Geometric parameter designed by the manufacturer for the second time, hopper car finite element model was established, rigid riveting position, poles and funnel mouth switching mechanism were simulated by employing the two units and rigid contact. According to the USA AAR standard, we calculated and analyzed the static strength, showing the node stress was beyond the standard about more than one hundred MPa, and maximum stress was 922MPa. Analyzing the calculating results, we found that all the materials met the allowable stress successfully after various improvement of hopper car body, except for the end part of the funnel carbody-T4003 stainless steel, of which the stress exceeded the criterion. In order to figure out the problem, we determined to change the stainless steel panels that were below the standard, separately. Utilizing ANSYS software to calculate quasi static load and Matlab to process the calculating data.The computational analysis showed the fatigue strength of two welding joints was weaker than the rest:the welding joints between car pillow on flat tail beam and end stainless steel hopper plate, pillow under beam plate and centre web plate, and suggested that the technology of two welding position mentioned above should be controlled strictly.This article offered certain theoretical basis for the structure optimization and fatigue resistance design of aluminium alloy hopper car in the very early structure design stages, mainly based on the virtual fatigue test of fatigue life analysis method.