城际动车组车轮廓形演化特点和原因分析

Analysis of characteristics and mechanisms of wheel profile evolution on intercity EMUs

针对我国某型城际动车组服役过程中车轮磨损速率高问题,开展车轮型面和研磨子影响研究的现场试验。第1阶段涉及多列动车组,使用LMA型面和持续高压作用的高硬度研磨子,第2阶段涉及1列动车组,第1镟修周期仅将半列车更换为LM型面,第2镟修周期进一步在全列车使用间歇低压作用的低硬度研磨子。结果表明,第1阶段城际动车组车轮磨耗不同于干线动车组,第2阶段2种型面的磨耗不存在本质差异,但更换研磨子材质和工作模式降低车轮磨耗速率。基于第2阶段数据,建立一种计算研磨子和轮轨接触对车轮磨耗方法,发现车轮名义滚动圆处由研磨子引起的磨耗速率在第2阶段的第1和2镟修周期分别为0.12 mm/万km和0.02 mm/万km,轮轨接触引起的磨耗速率为0.08 mm/万km。

Regarding the high wear rates of wheels on a type of intercity EMUs in China,field tests were performed to investigate the effects of wheel profiles and tread trimmers.In the first stage,multiple EMUs were involved,for which the LMA profile was applied and a type of hard trimmers operating continuously under a high pressure level was used.In the second stage,an intercity EMU was chosen and the test lasted for two re-profiling periods.An LM profile was applied instead of LMA on wheels of a half of the EMU.A type of soft trimmers was applied on the whole EMU,and was changed to operate intermittently under a lower pressure level.The results show that the wheel wear of the intercity EMUs is different from that of mainline EMUs during the first stage of the test.No essential difference is found in the wear behavior of LM and LMA profiles during the second stage of the test,but a softer trimmer and shorter operation time can indeed reduce the wheel wear rate significantly.Based on data collected on the second stage of the test,a method is further developed to calculate the wheel wear contributions of the tread trimmer and wheel/rail contact.It is found that in the first and second periods of the second stage of the test,the wear rate determined by the trimmers is 0.12 mm and 0.02 mm per 10000 km,respectively,at the nominal rolling circle(NRC),and that caused by wheel/rail contact is 0.08 mm per 10000 km.