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Alleviation of rolling contact fatigue on Sweden’s heavy haul railway[taliem.ir]

Alleviation of rolling contact fatigue on Sweden’s heavy haul railway

A test has been undertaken on Sweden’s Malmbanan, or iron ore railway, to reduce rolling contact fatigue (RCF) damage by developing a preventative maintenance regime involving routine grinding of the rails. In just the first 2 years of the test, the total cost of grinding plus rail replacements was reduced by almost 40%, while both the rail and track quality generally improved immensely. Although it may not be possible to reproduce such savings everywhere that RCF damage occurs, some lessons from the test are of general relevance. In particular, the development of even existing surface-initiated defects can effectively be halted by grinding and thereafter regularly reinstating, a profile which substantially removes loading from those cracks. In this test, the rate of metal removal by grinding was about 0.2 mm per 25 MGT. Methods were also developed for objectively monitoring the transverse and longitudinal profiles of the ground rail, and the depth of metal removed from the rail, i.e. the overall grinding “quality”. It would appear that the desired benefits of grinding can be obtained even if deviations of the transverse profile from a desired reference profile exceed specified limits over a significant fraction of the track.