Rolling stock condition monitoring using wheel/rail forces

Railway vehicles are efficient because of the low resistance in the contact zone between wheel and rail. In order to remain efficient, train operators and infrastructure owners need to keep rails, wheels and vehicles in an acceptable condition. Wheel wear affects the dynamic characteristics of vehicles and the dynamic force impact on the rail. The shape of the wheel profile affects the performance of railway vehicles in different ways. Wheel condition has historically been managed by identifying and removing wheels from service when they exceed an impact threshold. Condition monitoring of railway vehicles is mainly performed using wheel impact load detectors and truck performance detectors. These systems use either forces or stress on the rail to interpret the condition. This paper will show measurements taken at the research station outside Luleå in northern Sweden. The station measures the wheel/rail forces, both lateral and vertical, at the point of contact in a curve with a 484 m radius at speeds of up to 100 km/h. Data are analysed to show differences for various wheel positions and to determine the robustness of the system.