车轮廓形对城际动车组车轮Ⅰ类滚动接触疲劳的影响

Effect of Wheel Profile on Rolling ClassⅠContact Fatigue of Intercity EMU Wheels

就某城际动车组车轮的Ⅰ类滚动接触疲劳,选择一列动车组开展一个镟修周期的车轮廓形对比试验,其中1~4车用LMA廓形、5~8车用LM廓形。发现相同运行里程下,LM廓形车轮出现了Ⅰ类疲劳、但LMA廓形车轮未出现。基于SIMPACK建立了车辆动力学模型,并运用损伤函数开展疲劳预测。结果表明,导向轴低轨侧车轮易萌生Ⅰ类疲劳,半径在350~450 m范围内的小半径曲线最严重,镟后8万公里后LM廓形车轮的疲劳损伤峰值始终比LMA廓形高,考虑到现场车轮磨耗,可以解释试验中LM廓形发生疲劳而LMA不发生的现象。另外,疲劳峰值随里程呈现一定的波动,与现场观测Ⅰ类疲劳裂纹保持稳定而没有恶化的现象吻合。

To study the effect of wheel profile on classⅠrolling contact fatigue arising on wheels of intercity EMU(Electric Multiple Units),a comparison test was carried out on one EMU covering a period of wheel re-profiling.The LMA profiles was used for the wheels of the first to fourth vehicles of the EMU and the LM profiles was applied for the wheels of the fifth to eighth vehicles.It was found that there was no rolling contact fatigue damage on the wheels of LMA profiles,but classⅠrolling contact fatigue occurred on the wheels of LM profiles under the same running mileage.The vehicle dynamics model was developed with SIMPACK and the rolling contact fatigue prediction was conducted through the damage function.The simulating results show that the wheels of leading wheelset on the low rail are easy to generate classⅠrolling contact fatigue when EMUs pass through the curves especially for sharp curves within the radius of 350~450 m.The fatigue damage peak value of LM wheel profiles is always higher than that of LMA wheel profiles after a mileage of 80,000 km.Considering the wheel wear in the actual service,the phenomenon that LM profiles fatigue occurs but LMA does not can be explained.In addition,the fatigue damage peak value fluctuates with the change of the mileage,which is consistent with the phenomenon that the classⅠfatigue crack remains stable but does not deteriorate.