A research summary of corrosive sulfur in mineral oils

At present, a number of failures of transformers and reactors have occurred due to the resultant formation of copper sulfide (Cu
₂
S) in the windings, which has attracted wide attention. To date, corrosive sulfur in mineral oils has been regarded as the culprit, however, because of the complicated existence of sulfur element in mineral oils as well as other sources, the corrosive mechanism, restraining, detection method and how to minimize such problems are still the key and puzzled research points. In this paper, a comparatively detailed summary of research status about this phenomenon in recent time is present, and some useful research proposals are introduced as well.