Analysis Of The Influence Factors On Wheel/Rail Wear Of Heavy Haul Freight Car

With the rapid growth of China’s railway freight volume, the heavy haul transportation has become the development direction of the railway freight transport in china. However, because of the increase of the vehicle running speed and axle load leads to the serious problem of wheel/rail wear. The maintaining and replacing cycle is shortened enormously, thus, the problem of replacing steel rail and wheel prematurely not only make the railway transportation cost increasing, but also effect the normal railway transportation.The wheel/rail wear is inevitable in wheel/rail system and its reason is very complicate. Therefore, researching and analyzing the wheel/rail wear of the heavy haul freight car will be beneficial to decreasing the transport cost, reducing the environmental pollution and improving the efficiency of goods transportation, and has a certain practical significance on the development of transportation industry in our country.The simulation analysis method used in this paper is based on the theory of coupled vehicle/track dynamics. Dynamic analysis model for heavy haul railway vehicle curving is built by using the commercial software SIMPACK, and the nonlinear aspects of the vehicle system are taken into consideration. Based on the above analysis and dynamic models, study on the effects of relevant parameters of freight car and track alignment were made. According to the results of the researching, some corresponding measures to reduce the wheel/rail wear were summarized. Main conclusions are described below:(1) When the vehicle running on the rail line, the speed control in a certain range can effectively reduce the wheel/rail wear, the speed should be slightly lower than the highest speed of the line conditions allowed.(2) Longitudinal stiffness of the axle box, the friction coefficient of the center plate side bearing and the resistant diamond rigidity of the bogie have a great influence to the wheel/rail wear, lateral stiffness of the axle box and central suspension have a small influence to the wheel/rail wear.(3) Axle load effects wheel/rail wear significantly, we should improve the increasing of wheel/rail dynamic force and wear caused by the increasing of axle load, in order to meet the needs of the development of heavy haul transportation.(4) Reducing the friction coefficient of the wheel/rail can reduce the wheel/rail wear in a certain extent. But the friction coefficient of the wheel/rail must be strictly controlled, it should not be too large or too small to reduce the wheel/rail wear will be adversely affected.(5) The wheel/rail wear will be more serious when the curve radius is small. With the radius of the curves increasing, the wheel/rail wear decreases significantly. If the radius is larger than 1200m, the curve radius draws a little influence on the wheel/rail wear, with the curve radius changing.(6) If the deficient superelevation and the rail base slop are setted appropriately, it can reduce the wheel/rail wear and improve the curve negotiation performance of the heavy haul freight car.