Assessment of Corrosion on Rail Axles

摘要

Corrosion fatigue has been the reason for failure of rail axles in a number of accidents. This has led to stringent requirements to remove axles from service when corrosion is present. However the assessment of the corrosion is uncertain and mainly limited to a simple visual test which is heavily dependent on the inspector. Study of the growth of fatigue cracks from corrosion pits has enabled patterns in the development of the corrosion fatigue that gives an idea of the remaining life of an axle. An instrument has been developed that enables these patterns to be determined during inspection and this gives train operators a better method of sentencing the axle. This paper describes the patterns observed, and results of inspections of various axles demonstrating the feasibility of the instrument.