Fatigue Strength Analysis And Application Of Welded Bogie Frame

Bogie frame is an important bearing component of modern rail vehicles,and welding is one of its main connection forms.As the fatigue problem of the welded bogie frame becomes more and more serious,the need of the rail transit industry has become more and more urgent to solve such problems,and a comprehensive analysis of it is very necessary.Previous relevant studies have rarely considered the influence of uncertain parameters.Uncertainty analysis of structural strength of the bogie frame is also of important study value.For the fatigue problem of the welded bogie frame,this paper takes the welded bogie frame of a passenger train as the study object.Based on the established finite element model of the bogie frame,according to relevant standards and common analysis methods,combined with the finite element calculation and fatigue analysis data,the static strength analysis,fatigue strength assessment and fatigue life analysis of the bogie frame are carried out.At the same time,based on experimental optimization design methods and evidence theory,combined with MATLAB program,the influence of uncertain design parameters on the structural strength of the frame is analyzed.The study of this paper mainly includes the following aspects:(1)The analysis for the static strength problem of the bogie frame is carried out.Based on the established finite element model of the bogie frame,combined with relevant standards and material characteristics,the static strength of the frame is evaluated with the finite element analysis software.According to the calculation results,the location of the structural dangerous point is determined.(2)The study for the uncertainty of structural strength of the frame is conducted.Based on the finite element model of the frame,combined with the static strength analysis results,the key uncertain parameters are determined.Based on the experimental optimization design methods and evidence theory,the uncertainty analysis of the frame structural strength and the influence evaluation of the uncertainty design parameters on the frame structural strength are carried out.(3)Based on the structural strength analysis of the bogie frame,the study for the fatigue problem of the frame is carried out.On the basis of the established frame finite element model and relevant fatigue standards,the fatigue strength of the bogie frame is evaluated with the Goodman curve method.Based on the established finite element sub-model of dangerous parts of the frame,the fatigue life assessment of the bogie frame is carried out using the nominal stress method and equivalent structural stress method,combined with the finite element stress calculation and fatigue analysis data.Through the static strength analysis,structural strength uncertainty analysis,fatigue strength assessment and fatigue life assessment of the bogie frame,the analysis results of the strength and fatigue performance of the structure are obtained.The analysis idea and study results in this paper can provide a reference for the subsequent study on the fatigue problem of the welded bogie frame.