Dynamic Performance Analysis Of Locomotives Based On The Matching Between Worn Wheel-rail Profiles

Locomotives play a key role in power traction and wheel flange guidance. The riding quality of locomotives is closely related to the development of railway transport. With the increment of running speed, the requirement of dynamic performance is more critical for locomotives.This paper aims at improving SS4locomotive’s dynamics performance and is based on vehicle system dynamics theory. According to the actual arguments of locomotives and tracks, multi-body dynamic software named SIMPACK is adapted to set up a complete dynamics model of locomotives. The control variable method is adapted to analyze the effects of locomotive/track’s arguments on locomotives’dynamics performance and wheel/rail abrasion seriatim. Optimizing locomotives and tracks’arguments based on the calculation results, which is aimed at improving locomotives’dynamics performance and prolonging the service life of wheel/rail.Wheel profiles in different abrasion stages are tracked and measured for locomotives SS4. Then these wheel profiles are divided into four abrasion stages based on the different abrasion values. Four typical wheel profiles are pick out among the four abrasion stages, then matched with rail profiles in the measured wear stability period respectively. The effects of wheel profiles in different abrasion stages on locomotives’dynamics performance and wheel/rail abrasion are researched in this paper. Analysis results state that when the wheel profiles of type11match with rails in the wear stability period, locomotives can obtain the better dynamics performance. And the wheel profile of type Ⅱ has the good wear resistance and the contact stress between wheel and rail can be reduced effectively.When locomotives running on the line, the car body and bogie are always subjected to load from different directions and live load due to the vibration of locomotives themselves and uneven railways and so on. In this process, suspension system has the effect of load transmission and attenuation, thus locomotives can run safer and more stable. Therefore, reasonable suspension parameters are also an important guarantee of the safe and stable operation of locomotives. This paper also researches the effect of different suspension parameters on locomotives’dynamics performance. A group of new suspension parameters are put forward according to the calculation results, which provides theoretical basis for the optimization design of suspension system of locomotives.As an important part of wheel/rail relationship, the structure of rails also has a critical effect on locomotives" dynamics performance and wheel/rail abrasion. From the perspective of rail cant and curve superelevation, this paper researches the effect of structure parameters of rails on locomotives’dynamics performance and wheel/rail abrasion. Analysis results state that increasing rail cant to1/20can not only make locomotives obtain better dynamics performance but also restrain wheel/rail abrasion effectively. When superelevation is80mm and curve passing speed is64km/h, locomotives can pass through a small radius curve safely and steadily, meanwhile wheel/rail can obtain better abrasive resistance.