Comparison of spectrographic and ferrographic analysis of crankcase oils from the High Speed Train

Abstract

Spectrographic analysis has been in use for some years as a routine preventative maintenance tool to detect early failures of diesel engines, including those of the High Speed Train (HST). Ferrography is a newer technique which is claimed to have merit in condition monitoring of lubricants in service, but few workers have attempted to apply it to the diesel engine. This paper compares the two techniques for the engines of the HST.Spectrographic analysis indicated two problems on one of the seven engines monitored weekly which ferrography did not detect. For three other engines where spectrographic analysis had given critical results, ferrography was of little help. Moreover, on three other engines ferrography could have led to unnecessary engine examination. It is concluded that ferrography is of limited value in either the direct read or analytical modes in this application which involves a high proportion of non-ferrous components, whereas spectrographic analysis continues to be an invaluable preventative maintenance tool