Research On Optimization Of A-type Subwav Stainless Steel Car Body Structure

With the development of China's national economy and continuous expansion of city scale,subway has become more and more popular as an effective means of solving urban road congestion and environmental pollution problems.Taking subway has played an important part in many citizens' daily life.The research on optimization of car body structure not only ensures the safety of normal driving,but also reduces the production cost and energy.Firstly this paper introduces the development of stainless steel car body at home and abroad and the development history of structural optimization.Stainless steel car body is an important direction for the development of urban rail transit in China.Reasonably optimizing the car body structure is an important means of lightweight and modernization.Then a certain type A subway stainless steel car body is taken as the research object.According to the finite element theory,the finite element modeling and simulation analysis are carried out by using HyperMesh software.The results show that the static strength,stiffness,stability and modality of the car body all meet the corresponding standards.Based on the analysis of the simulation results,it is found that there are redundant solder joints on the side wall and still design margins on the roof and chassis beam structures of the car body.Finally,by using OptiStruct software,on the one hand,the side wall solder joint units with 6.0mm in diameters are topology optimized.Based on the optimization results and considering the welding process and engineering practice,the solder joint layout of the side wall is artificially improved.Compared with the original design scheme,the number of solder joints on the side wall after optimization and improvement is reduced by 960.On the other hand,the beam structure of the roof and the chassis is dimension-optimized.After optimization the plate thickness of the roof curved beam,the large beam and the small beam of the chassis are reduced.And the topological position of the bottom beam is improved to make the roof curved beam,the side wall column and the chassis beam are in the same cross-section in the longitudinal direction of the car body as far as possible.Combining the two structural optimization and improvement schemes,the static strength,stiffness,stability and modality of the car body after optimization and improvement all meet the corresponding specifications.The car body mass is reduced from 8.049t in the initial design scheme to 7.712t,and the weight loss is 0.337t,with obvious weight loss effect.The number of welding spots on the car body is reduced,which reduces the welding workload,thus saving the manufacturing costs and improving the economic benefits.Thereby the results have certain reference value in practical engineering applications.