利用MMS-2A型微机控制摩擦磨损试验机开展介质工况下的轮轨粘着特性试验,研究干态、水、油、砂、树叶等介质对轮轨粘着系数的影响。结果表明:不同介质工况下的轮轨粘着系数明显不同,干态下轮轨粘着系数最大,油水介质下粘着系数最小,加水和油将显著降低轮轨粘着系数,且油介质下的轮轨粘着系数明显小于水介质下的粘着系数;随环境湿度增加轮轨粘着系数明显降低,当湿度从20%增加到100%时,粘着系数将降低约17%;干态和油水介质下,随轴重增加轮轨粘着系数呈明显增加趋势;轮轨接触面间加入新鲜树叶后粘着系数将降低,树叶与水共同作用下的轮轨粘着系数最小;通过撒砂能提高水油介质工况下的轮轨粘着系数,但会加剧轮轨试样表面损伤,导致剥落损伤出现。
The adhesion experiment of wheel/rail under different medium conditions is investigated by a MMS-2A testing apparatus.The effects of dry condition,water,oil,sand and leaves on adhesion coefficient of wheel/rail are explored in detail.The results indicate that the adhesion coefficient of wheel/rail is different under different medium conditions.The maximum adhesion coefficient is found under dry condition.The adhesion coefficient is smallest with mixed oil and water.Adding water and oil can remarkably decrease adhesion coefficient of wheel/rail.Furthermore,the adhesion coefficient under oil condition is smaller than that of water condition.With the humidity increasing,the adhesion coefficient of wheel/rail would decrease.When the humidity increases from 20% to 100%,the fall of adhesion coefficient is about 17%.With an increasing axle load,the adhesion coefficient of wheel/rail increases under dry,oil and water conditions.Adding fresh leaves to contact zone causes a drop of the adhesion coefficient of wheel/rail.The adhesion coefficient is smallest under leaves and water condition.Sanding can increase adhesion coefficient of wheel/rail under water and oil conditions.However,sanding can aggravate the spalling damage of wheel/rail surfaces.