In some cases, assets end up with mixed fluid types for various reasons. This can cause serious issues with material compatibility or dielectric strength of the insulation. Silicone fluid is one fluid type that is not miscible with mineral oil. Traces of silicone liquids present in mineral oil can lead to foaming during vacuum dehydration and filling processes. Foaming can result in inadequate dielectric strength and eventual mechanical failure.
What method is used to analyze the sample?
TJH2b has developed a proprietary method to detect silicone fluid contamination in mineral oils.
Where can I find sources on issues caused by foaming and silicone contamination in mineral oil?
IEEE C57.105-2015
ASTM D892-03
What do the results indicate?
The test results show the silicone contamination level in ppm. Even concentrations as low as 10 ppm may indicate a significant risk of excessive foaming during vacuum dehydration/degassing processes. Contamination sources (e.g., seals, gaskets, prior additives, or cross-contamination) should be investigated before proceeding with insulating fluid treatment or purification.