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Comparison of Available Silicone Rubber Coatings for High Voltage Applications
International Journal of Emerging Electric Power Systems (2008)
  • Majid Sanaye-Pasand, University of Tehran
  • Ali Naderian Jahromi, University of Waterloo
  • Ayman H El-Hag, American University of Sharjah
  • Shesha H Jayaram, University of Waterloo
This paper presents the results of an investigation on evaluating room-temperature-vulcanized (RTV) silicone rubber coatings for high-voltage insulators of substations and overhead transmission lines. It is based on tests conducted for three different available RTVs that are currently used by utilities. The study compared three commercial coatings: RTV-A and RTV-B filled with ATH (aluminum tri-hydrate) as the primary filler, and RTV-C filled with silica. The relative comparison between them is based on their electrical and chemical characteristics. The evaluation employed standard and research-based evaluation methods, including the salt fog test, the inclined plane test, thermo-gravimetric analyses (TGA), thermal conductivity measurement, soaking in water, the mechanical test, and SEM photographs. Results of the inclined plane test showed that the silica-filled coating is not resistive against tracking and erosion compared with ATH-filled coatings. It was observed that filler size is one of the main reasons for better performance of RTV-A compared with RTV-B, whereas both have ATH as the primary filler. The higher thermal conductivity of RTV-A resulted in a very good performance in the salt fog test and the IPT.
  • insulator,
  • high voltage,
  • silicone rubber,
  • RTV coating,
  • leakage current
Publication Date
March 6, 2008
Citation Information
Majid Sanaye-Pasand, Ali Naderian Jahromi, Ayman H El-Hag and Shesha H Jayaram. "Comparison of Available Silicone Rubber Coatings for High Voltage Applications" International Journal of Emerging Electric Power Systems Vol. 9 Iss. 1 (2008)
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