Tyred wheels without braking: structural optimization

Tyred wheels were used in the past when labour and fixed costs were much less important than today. Modern monobloc wheels benefitted from advanced numerical tools (finite elements) and improved tooling, making them the most convenient solution. Nevertheless, tyred wheels can still be an interesting advantage when both design and maintenance are re-considered taking into account the numerous changes in the railway vehicle design, i.e. the development of braking systems acting on dedicated surfaces (brake discs mounted on the axle, on wheel web, on parallel axles, on engine shaft, etc.) When the thermal load due to tread braking is removed, the structural calculation of tyred wheels can be totally revisited leading to lighter, quieter and much cheaper solutions. The paper discusses some basic considerations on the oversizing of conventional tyred wheels, showing the potential advantages. Outline of further activities are provided, including fretting analysis and wheel centre design.