Structural durability of cast aluminium gearbox housings of underground railway vehicles under variable amplitude loading

Cast aluminium gearbox housings for railway vehicles are complex shaped components undergoing stochastic stresses during service. Early failures of housings led to broad investigations in order to clarify the causes. By a methodology determining the highly stressed areas, the load spectrum for different operational conditions by service strain measurements, the component related material behaviour, fatigue-life calculations and laboratory proof tests, criteria for optimum design, material selection and quality control were worked out. The methodology enabled the design of new housings that would meet the required failureless operational service.