Research On The Wheel/Rail Wearing Of The Tramcar

The relationship between wheels and rails is the foundation link of the urban rail transit, and the serious wear of the wheels and rails is always the complex problem which restricts the development of railway transport industry for a long time. A better relationship between wheels and rails can not only reduce the wheel/rail wear and decrease the operation cost, but also improve the stability of vehicle and insure the comfort of the passengers.Focus on the contact status of powered/independent wheels rolling on the rails, a large number of measured wheel profiles were statistical and typical wheel profiles were chosen to build the three-dimensional solid finite element models. By analysing the calculation result of contact spots and contact equivalent stress, the wear regulation of the powered wheels and the independent wheels were got. The conclusions show that with the wear of the wheels when operation on the rail, the powered wheels can keep its profile very well and the tread match well with rail profile, while the match degree of the dependent wheels flange is relatively high.The influence of different parameters on the contact status of the wheels and rails was also anlysized in this paper. The parameter of different lines such as the rail base slope, curve widening and the superelevation of outer rail is not the same, and attack angle changes during the operation. All these parameters can influence the contact status more or less. The influence of two parameters on the wear, Rail base slope and attack angle, were anasized. It shows that wheels contact better with the rail under the rail base slope of1/40, and the side wear of the outer rail would be slower with the increase of the inner rail base slope. With the increase of the attack angle, the contact stress would be higher. The contact status of the tread is almost the same, while the wear of the flange would increase.In order to ensure the other vehicles normally moving, the groove rails are laid in the lines of urban tramcar where the tramcars run along with other vehicles or traffic jam occurred. Because of the existence of flangeway in groove rails, the contact condition between wheels and groove rails is more complex than thar between wheels and common rails. However, the contact analysis of groove rails is relatively rare. Based on a large amount of groove rail profiles which were measured from the lines of urban tramcar, the contact status between wheels and groove rails were analyzed in this paper. The result shows that, when powered wheels matched with groove rails, the root of wheel flange and the gage corner of rail are the mainly wear positions, where the Von Mises stresses are relatively larger. When independent wheels matched with groove rails, the contact positions are mainly concentrated on the middle part of tread and the top of rails, and most of the Von Mises stresses are less than the yield limit of material. The Von Mises stresses between Ⅱ type wear groove rails and wheels are relatively less.This paper is for the wear problems of tramcar wheels and rails. The contact status between different wheel and rail profiles is analyzed, and the effect to wheel/rail wear under different rail base is calculated as well. The results of this paper could provide the theoretical foundation for the optimization of wheel/rail profiles in the future.