轮轨非对称接触及形面损伤问题分析

随着列车运行速度的提高,车轮形面损伤问题也日益严重。车轮形面损伤分为踏面剥离、车轮失圆和轮缘磨耗等类型。车轮形面损伤后会导致车辆的不平稳运行,使车辆一方面产生低频、中频和高频的振动,影响车辆的运行平稳性和乘坐舒适性,另一方面会引起车辆内部的噪声,车轮损伤严重时甚至会直接导致车辆脱轨事故的发生。车轮损伤问题是由轮轨接触非对称现象所引起的,轮轨非对称接触分为对称踏面与非对称钢轨的接触、非对称踏面与对称钢轨的接触以及非对称踏面与非对称钢轨的接触三种类型。当车轮形面或钢轨损伤后,就会导致轮轨非对称接触的发生,而轮轨非对称接触又会加剧车轮形面的损伤。为了提高车辆的动力学性能和运行稳定性,必须避免轮轨强非对称接触的发生。

Analysis of wheel-rail unsymmetrical contact and wheel surface damage problem

The wheel surface damage problem turn more and more serious with the running speed increase of railway vehicles.General speaking,wheel surface damage can divided into three types:wheel tread spalling,out-of-round of wheel and wheel flange wear.The unstable running of the railway vehicles can be caused by wheel surface damage,and the low frequency,middle frequency and high frequency vibration may be occurred by the vehicles,influence the riding index of the vehicle and decrease the passenger comfort.On the other hand,it also can lead to the noise inside the vehicle.The railway vehicle derailment maybe happens when the wheel surface damage is serious enough.The wheel surface damage problem is caused by the unsymmetrical wheel-rail contact which is consisted of symmetrical wheel tread combined with the unsymmetrical rail,unsymmetrical wheel tread combined with the symmetrical rail and unsymmetrical wheel tread combined with the unsymmetrical rail.The unsymmetrical wheel-rail contact can be formed when the wheel surface damage or the rail head damage.The forming of the unsymmetrical wheel-rail contact can aggravate the damage of wheel surface.To improve the dynamic performance and the stability of the vehicle,the strong wheel-rail unsymmetrical contact must be avoided.