Title |
A Study on the Microstructure Analysis and Dielectric Properties of Porcelain Suspension Insulators |
Authors |
김찬영(Kim, Chan-Yeong) ; 김주용(Kim, Ju-Yong) ; 송일근(Song, Il-Geun) ; 이병성(Lee, Byeong-Seong) |
Keywords |
Suspension insulator ; Porcelain ; Glaze ; Crystalline phase ; Microstructure ; Porosity |
Abstract |
The paper provides the results of microstructure analysis and dielectricproperties of porcelain suspension insulators. The evaluation of characteristics was also made as a function of the manufacturers and fabricated years for the experimental specimens which had been used in real distribution lines. Even though the series A contained higher alumina contents than the series B, the densification of series A was lower than that of series B, resulting from much porosity. The microstructure investigation confirmed that series A had much porosity than series B. The series A contained quartz (SiO_2), mullite (Al_6Si_2O_{13}), corundum(Al_2O_3), and cristobalite (SiO_2) phases. However, the series B had no cristobalite phase which had very high thermal expansion coefficient. Also, the tanΔof series A was more abruptly increased than that of series B as increasing temperature. The elevated temperature may make much expansion of cristobalite crystal than other crystals, resulting in crack and puncture inside cap during the summer days. |