Journal spring is a rubber part for train used as a foundation for coil spring to be mounted. It acts as a vibration control component of the dynamic load that bogie received, and also reduce the friction and direct impact between steel coil and the bogie metal frame.
Journal springs also play a role in reducing friction and direct impact between the coil spring and the metal frame of the bogie. Without journal springs, there is a possibility of direct friction between the metal components, which can result in faster wear and potential damage to the suspension system. With journal springs, these rubber components act as buffers that absorb impact and reduce friction between the metal parts
