The Applied Study On Numerical Simulation Of Punch Forming In Railway Freight Train Manufacturing Industry

In this dissertation, the applications of numerical simulation of punch forming in railway freight train manufacturing industry are studied. Various theories with respect to mechanical model, material, contact and elements, etc. are presented in the numerical simulation of punch forming. All numerical simulations of punch forming are done by software package of DYNAFORM/LS-DYNA on the basis of none linear explicit calculation method.This dissertation focuses on applicated research of numerical simulation of several typical punched parts of freight train.Firstly, by research on numerical simulation of punch forming side plates of box train, the successful application of simulation in optimization of punch process program is realized. As a set of large-size real dies and fixtures costs much, it is impossible to verify different process programs with the real dies and fixtures. Therefore it is very feasible and economical to reproduce the results of different process programs in the computer by numerical simulation method.Secondly, by research on numerical simulation of flanging hand wheel, the successful application of simulation in review of product processing is realized, among of which FLD curve is the major means of judging smooth forming of the parts.Thirdly, by research on numerical simulation of multistep forming spring case, it is realized that by simulation, calculations of multistep forming can be successfully made, which plays a very positive role in choosing appropriate drawing material.Furthermore, the application of Pro/E and numerical simulation software DYNAFORM in the project and the manufacture of forming dies of bottom side doors are also described in this dissertation.