

In order to study the influence of the position of without braking function on the safety of empty freight trains, a dynamic model of the locomotive and vehicle-track coupling system was established based on the theory of vehicle system dynamics and the theory of train-track coupling dynamics. And the safety indicators of the empty freight train’s lateral wheelset force, derailment coefficient, and wheel unloading rate were analyzed and compared with the dynamic safety indicators of the empty freight trains with normal braking function, while the vehicles without braking function located in the front, middle and rear parts of the freight train. The results show that during the service brake conditions, whether there are vehicles without braking function or not, the safety performance of the empty freight train is not much different, and all meet the requirements of the GB5599-2019 standard, the safety performance of the vehicles without braking function is not significantly different from that of the normal vehicles, the lateral wheelset force and the derailment coefficient are slightly greater than those in other parts while the vehicles without braking function located at the front part of the train, and the dynamic performance is not much different when the vehicles without braking function located in the middle and rear of the train.