Study On Fatigue Test Method Of The EMU Axles

Axle is an important component of rail vehicles,which directly affects the safety and service life of vehicles.Two methods of simulation and test are usually used to study the fatigue strength of the axle.The two methods are supported by each other.The two can be used to study the fatigue strength and service life of the dangerous cross section of the axle.This paper introduces the axle strength design standard at home and abroad at first.And then calculates the train axle of a high speed EMU according to the European and Japanese standards.Finally compares the differences and reasons of the evaluation results systematically.Fatigue test is an important research method,a new bending fatigue test method is put forward after the comparison of different rotating bending fatigue test method.The simulation results show that the damage caused by the two methods is not equal when the loading load keep the same,and the loading load needs to be calculated based on the damage equivalent principle to keep the same damage.In order to study the axle damage during the actual operation of vehicles,the rigid flexible coupling dynamic model of EMU considering wheelset flexibility was established by Simpack.The dynamic stress of the axle under various operating conditions was simulated,and the damage calculation was carried out based on the cumulative damage principle.In addition,considering the impact of the wheel flat scar on the fatigue strength of the axle,the dynamic stress level of the axles of the new and old flat scars under different lengths and speeds is simulated,and then the cumulative damage is calculated.It is found that the wheel flat scars will cause great damage to the axle,especially at the low speed and long flat scars.Finally,the strength checking calculation of the gauge variable wheelset is carried out,and the fatigue test method is analyzed.A preliminary fatigue test scheme is put forward for the variable wheelset axle of the gauge.