Abstract
In the quest to maintain the reliability and safety of railway systems, vibration signatures emerge as a crucial diagnostic tool for identifying and tracking the progression of railway bearing health. It is important to note that, in the case of spall deterioration, temperature variations may only become noticeable once spalling has spread extensively across the raceway. Hence, a comprehensive understanding of the effects of lateral loading under various train speeds at empty and full railcar loads is important. Surprisingly, limited research has been carried out or made publicly available on the effects of lateral loading on the performance of railroad tapered-roller bearings. Motivated by this, researchers at the University Transportation Center for Railway Safety (UTCRS) are conducting laboratory testing utilizing the available dynamic bearing test rig to explore the effects of lateral loading on bearing performance. The laboratory testing is performed on Association of American Railroads (AAR) class F and K bearings, which represent about 85% of the railroad bearings utilized in freight rail revenue service. Lateral loads are applied by a specially designed hydraulic cylinder setup that can deliver up to 44.5 kN (10 kips) of lateral force on the bearing while in operation. The laboratory testing is designed to mimic lateral forces that bearings will experience during events like hunting, buckled track, uneven track, and instances where trains are navigating curved sections of track. This study sheds light on critical factors influencing bearing performance in the rail industry, particularly the impact of lateral loading on bearing performance and operating temperature fluctuations. Its unique contribution lies in exploring the previously uninvestigated effects of lateral loads on bearing vibration (in addition to temperature). Ultimately, the aim is to enhance the long-term reliability and safety of rail systems by identifying and mitigating factors that compromise bearing performance. Based on the insights gained from this study, the team is refining vibration and load measurement sensors to gather even more precise data on lateral load effects in future experiments.
