Use of Nanosilica in Silicone Rubber Coatings for Ceramic Insulators in Coastal Areas - Field Results

Field experiments were performed to study the relative performance of nano size silica filler (nanosilica) and micron size silica filler (microsilica) as fillers in silicone rubber as coatings for ceramic or glass insulators in coastal areas. Leakage current was measured and recorded for 45 days of exposure to a coastal environment that is recognized by the utility as critical. After field exposure, the insulators had their surface contamination evaluated. The results indicate that nanosilica filled silicone rubber had lower leakage current values than microsilica filled silicone rubber coated insulators due to less surface contamination.