Wheel profile design based on rail profile expansion method

Abstract

Firstly the contact geometry of UIC high-speed wheel/rail profile SI002/UIC60 and Chinese quasi-high-speed profile LMa/CHN60 is analyzed.The analysis result shows LMa/CHN60 profile has too low degree of conformity,which would have detrimental effects on wheel/rail wear and rolling contact fatigue.So,from the view point of altering the rail contact status,rail profile expansion method is researched numerically,and the partial rail profile expansion method is adopted to design wheel profile having higher degree of conformity with Chinese 60 kg/m rail.The vehicle track coupling dynamics simulation shows that the designed profile has critical speed about 400 km/h,and relatively better curving performance than LMa profile.Finally,the calculation of the wheel/rail elastic non-Herzian rolling contact shows that compared with the LMa profile the contact area,contact stress etc.of the approaching rail side contact have little changes,while the leaving rail side has obvious en-large in contact area and substantial decrease in contact stress,for approximately 20%.This design can enable a broader wheel/rail running band,alter the contact position and fTequency,which will mitigate wheel/rail rolling contact fatigue.