Wheel-Rail Profile Matching Relationship of EMU Train

In order to study the matching relationship between different wheel treads and rail profiles for EMU (electric multiple unit) trains, a comparative study was made by investigation of the wheel-rail contact geometry parameters, static mechanical properties, running stability of vehicles, and wheel-rail wear. Computational results by CONTACT and SIMPACK show that the running stability of vehicles on the 60N rail is better than that on the 60 kg/m rail because the 60N rail head is improved to be more smooth and the wheel-rail contact area is kept in the middle position of the rail head. When using two types of wheel treads, LMA and S1002CN, to match with the 60N rail, the contact spot area of the 60N rail surface can get a better proportion of sticking area and slipping area, so the general wheel-rail damage and wear are reduced effectively in the operation. However, the contact stress between the 60N rail surface and the LMA tread or the S1002CN tread with a small displacement is big, and hence may result in a large vertical wear. When the lateral displacement is 4-8 mm, the contact stress between the 60N rail surface and S1002CN tread is smaller than that of the 60 kg/m rail, and the wheel-rail wear is lower for vehicles negotiating curves. Therefore, the contact relationship between the 60N rail surface and the wheel tread is more favorable for the running stability of EMU vehicles, but wheel-rail contact points focused on the middle will aggravate the vertical wear.