Wheel/Rail Contact Creep Curve Measurement and Low Speed Wheel Climb Derailment Investigation

This paper presents wheel/rail (W/R) contact friction coefficients and creep curves measured by using the Rolling Contact Fatigue Simulator (RCFS). Measurements showed W/R contact friction coefficients and slopes of the creep curves during the transition from partial slip to full slip increase with the decrease of contact stresses under dry contact conditions. Even though the friction coefficient is smaller due to water lubrication, it has little effect on the creep curve transition slope. NUCARS^® (NUCARS® is a registered trademark of TTCI) turnout simulations showed that friction coefficient variation with wheel loads may have detrimental effect on flange climb derailment for the case of new wheels running on new rails. Measured W/R contact creep curves under different wheel load conditions are recommended for flange climb derailment investigations.