Lightweight Design Of 200km/h Electric Locomotive Body Oriented To Static And Dynamic Performance Improvement

As the main locomotive of current railway groundline passenger transport,with the rapid development of society,the speed of groundline locomotive has been increased for many times,and the groundline locomotive of 200km/h has a mature technical platform.The development of 200km/h Electric Locomotive needs in-depth research on the lightweight design of locomotive,so as to meet the axle load parameters matched by speed increase and ensure the operation safety of locomotive.As the main load-bearing structure,the locomotive carbody is the main object of locomotive lightweight design.In order to achieve the goal of lightweight design and ensure sufficient strength and stiffness of the body structure,it is necessary to study the static and dynamic performance of the body under multiple working conditions,and realize the purpose of body lightweight by using the design method of size optimization.By sorting out the current research status in the field of lightweight design,combined with the research progress and latest achievements in this field at home and abroad,this paper combs the lightweight design process of carbody steel structure.The main research contents and research results are as follows:(1)Static and dynamic performance analysis and test verification of vehicle body.Based on the initial structure of 200 km / h electric locomotive body,the static strength is calculated under six typical operating conditions,and the natural vibration frequency of the body steel structure is calculated and analyzed under free state and servicing state.At the same time,the calculation results are verified in combination with the static strength test.The results show that the structural strength of the whole vehicle has a large redundant space for optimization design.(2)Size optimization design of car body structure.Through the analysis of the static and dynamic performance of the car body structure,the underframe and cab structure with the largest weight proportion are taken as the optimization design domain,the plate thickness in the underframe and cab steel structure is defined as the design variable,and the optimized plate thickness parameters are obtained under the constraint that the structural stress does not exceed the material yield limit.According to the optimization results,the parameters of design variables are reduced in varying degrees.The total weight of car body steel structure is reduced from 13.453 t to 12.78 t,and the weight reduction rate is 5%,of which the weight reduction of underframe accounts for 97%.(3)Static and dynamic performance analysis and verification of optimized structure of vehicle body.According to the optimized structural parameters,the static strength of the car body structure under typical working conditions is calculated and checked,and the natural vibration frequency of the car body steel structure in free state and servicing state is calculated.The check results show that the car body stress meets the design requirements,and the first-order vertical bending vibration frequency of the car body in the servicing state is12.03 hz,which meets the modal design requirements of the car body.By studying the multi working condition lightweight design method,this paper can further verify the feasibility and practicability of structural optimization design of carbody steel structure,and provide reference for the weight limitation of locomotive due to speed increasing problem.