The Fatigue Strength Of Welding Structure In Railway Vehicle Based On Ansys

Fatigue failure is the major failure form of welding structure, the fatigue analysis of welding structure is very important to the design of the welding structure and the design of welding procedure. The complicated welding structure is always composed of different welding joints and metal bases, the different welding joints and metal bases of different notch cases have different mechanical properties fatigue performances. So it is very practical that introducing the welding joints classification in fatigue strength analysis of complicated welding structure.This article will introduce a method of The welding fatigue strength analysis of classification that aim at the diversity of welding joints and metal bases which based on DIN15018-1, in consider of the classification of concentration of stress and load cycles and notch case, and this article will elaborate a secondly development method of ANSYS which is realized by hybrid programming of Fortran95and C++MFC. The welding fatigue strength analysis of classification program is mostly composed of three components, fist, the realization of classification of welding structure, to realize the classification of welding structure, we should classify the nodes in different notch case of welding joints and metal bases in the procedure of building finite element model and output the CDB file by ANSYS and read the classification information of CDB file; second, the realization of the welding fatigue strength analysis of classification, there are Euler angles of elements and nodal component stresses in the element coordinate system in the result file of analysis of mechanism that outputted by ANSYS, the Euler angles of elements and nodal component stresses are extracted by secondly development of ANSYS result file, the maximum stress, minimum stress, average stress, stress ratio and stress amplitude are calculated based on the method of transformation from multi-axial stress to single axial stress which is gave by ORE B12/RP17report, the factor of safety is calculated based on classification information and the method of fatigue analysis of welding structure which is gave by DIN15018-1standard; The realization of the visualization of fatigue analysis of welding structure, the factor of safety, maximum stress, minimum stress, average stress, stress ratio and stress amplitude are written in the position of node component stress in result file, the contour map of factor of safety could be displayed by the post processor if ANSYS.This article classify the butt weld, single fillet weld and double fillet weld of the welding frame of the bogie of multiple unit train, and take the analysis of fatigue strength of classification of welding frame according to DIN15018-1standard and realize the visualization of the results of fatigue strength analysis. By compare with the results of the common fatigue evaluation methods by Japer and Goodman fatigue strength curve, the accuracy and practical value are proved.