Research On AWS D1.1 Code And Its Applications In Rail Vehicles

Since the 21st century,China's economy has developed rapidly and the railway transportation industry has become increasingly advanced.Urban rail transit system has gradually become an important choice for citizen because of its large traffic volume,punctuality and high speed.With the higher requirements of the stationarity,power dynamic and comfort of the subway,rail vehicle companies have been dedicated to designing the vehicles with higher requirements.The bogie is an important part of the metro vehicles,as it carries the car body and reduces abrasion between the wheels and the rails.Therefore,whether the bogie frame design is reasonable directly determines the safety of the subway.Hence,bogie frame research is of great significance to bogie design.In this paper,the static strength,modal and fatigue strength of a Metro Bogie are analyzed to verify whether the structure of the bogie meets the safety requirements.The major work is summarized as follows:Firstly,the American Standard AWS D1.1 "Structural Welding Code-Steel" is studied.The basic content of AWS D1.1 standard is expounded and the basic steps of evaluating component fatigue based on nominal stress method is introduced.Comparing AWS D1.1 standard with BS7608-2014 standard in application scope,S-N curve and welded joint It is found that the calibration criteria can be selected according to different actual needs;Secondly,the static strength analysis of metro bogie frame is carried out.Based on the established 3D solid model,the finite element pre-processing software HyperMesh is used to clean up the geometry and divide the grid to establish a finite element model.The working conditions of the supernormal load and the simulated load are determined according to UIC615-4 "Bogie frame structure strength test".Static analysis is conducted on the bogie frame,and the result is evaluated with the 4th strength theory,the safety factor is calculated,indicating that the bogie frame meets the static strength requirements;Subsequently,the modal analysis of the subway bogie frame is carried out.The ANSYS software is used to analyze the modal of bogie frame without constraints.The natural frequency and mode shape of the first 14 modes are obtained by calculation.The analysis of the frame design effectively avoids the phenomenon of resonance and meet the requirement of in-service working;Finally,the fatigue strength of the Metro Bogie is analyzed according to the strength calculation results.Based on the nominal stress and UIC615-4 standard as loading conditions,key parts of the bogie frame is evaluated the fatigue strength under AWS D1.1 standard in bogie frame are checked by AWS D1.1 standard.The result is calculated that fatigue strength meets the requirement of the bogie frame.