The fracture of freight wagon wheels braked through wheel mounted cheek discs (TN-MET-005)

Since its introduction the wheel-mounted disc brake has precipitated a number of brittle fractures of the braked-wheels of 25t axle load, diagonally-braked freight vehicles. Detailed metallurgical examination has failed to provide a satisfactory explanation. Extensive dynamometer testing together with line tests have shown that massive cyclic strains (of thermal origin)...