Weighing in on better wheelsets
Modernising railway transport requires advances in many areas, including the manufacture of sophisticated wheelsets to ensure the smoothest operation possible. The EU-funded project 'Wheelset integrated design and effective maintenance' (WIDEM) aimed to design and test strong wheels and axles that reduce maintenance, increase safety and minimise life-cycle costs. The project re-examined how to design and maintain rail wheelsets using dynamic calibration and a unique roller rig on which reality-like operation can be simulated. To achieve its objectives WIDEM conducted research in order to define standards for wheelsets load spectra and develop flexible multi-body models to understand vehicle track interaction. This has led to excellent simulation of running conditions that yield accurate deformability of wheelsets, bogies, car body and track, accurately reflecting wheel-rail contact forces. In addition, the project assessed relevant materials and their properties to outline procedures for comprehensive fatigue tests on wheels and axles, standardising evaluation across Europe. WIDEM then successfully defined new design methods for wheelsets to optimise wheelset geometry. Another important achievement was the development of new methods to detect cracks in wheelsets, which despite being a rare occurrence must be investigated systematically to improve safety. This was achieved using phased array ultrasonics and time-of-flight ultrasonics, while major headway was made in deriving crack growth rate parameters under both plane and rotating bending conditions. Data from all the different aspects of wheelsets, axles and potential cracking were collated together to elaborate a more powerful approach to building better rail systems and advancing road safety. This approach will serve to unify European standards and streamline rail transport across the continent.
