50kg／m钢轨踏面掉块缺陷分析

Analysis on Swap Block on Tread of 50 kg/m Rail

50 kg/m钢轨在使用一段时间后踏面出现掉块缺陷。采用光学显微镜、图像仪和低倍检验等方法对钢轨踏面掉块缺陷产生的机理进行了分析和研究。结果表明,掉块缺陷的形成是由于钢轨滚动接触疲劳伤损所致。改善轮轨接触方式,减少钢轨踏面的轮轨接触应力,可以减缓曲线钢轨踏面压溃、剥离裂纹和浅层状剥离掉块伤损的出现,通过对钢轨进行及时的预防性打磨,是预防和减轻滚动接触疲劳伤损的最有效方法。

While 50 kg/m rail was used for a period of time, on the tread of rail swap block could be found. Defects were analyzed by optical macroscopy. The result shows that rolling contact fatigue failures caused swap block defects of rail. The improvement in wheel track contact mode and redution of contact stress between rail tread and the wheel might slow down rail tread bruising, the peeling cracking, shallow layered strips swap block. The preventive rail polishing is the most effective countermeasure.