Vol.7 No.1 AASP14 (87-88-89-90-91-92-93-94-95-96-97- |
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Academic Articles | |||||
Regular Paper | Vol.7 No.1 (2015) p.102 - p.107 | ||||
A Study on Insulation Degradation in Thermally Aged Ethylene Propylene Rubber Using Volume Resistivity Measurement |
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Tariq ALSHAKETHEEP1, Kenta MURAKAMI2, Naoto SEKIMURA1 | |||||
1 School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8656, Japan |
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Abstract | |||||
This study presents electrical condition monitoring technique aiming at measuring volume resistivity (ρ) precisely for the tubular-shaped cables insulators. Tubular electrodes were designed to detect ρ for nuclear grade flame retardant ethylene propylene rubber (FR-EPR) insulated cables that underwent thermal accelerated ageing. FR-EPR insulated cables were heated at 125 °C for 5040 hours by two methods: with jacket and without jacket, while only FR-EPR cable with jacket was heated at 150 °C for 336 hours. ρ in insulators heated with jacket sharply decreased at ageing times 800-3480 hours and 300-336 hours during ageing at 125 °C and 150 °C respectively, hence obeying “induction-time” behavior as confirmed from elongation at break degradation curves at similar ageing conditions. Reduction of ρ in insulators heated at 125 °C without jacket is less significant compared to ageing with jacket. |
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Keywords | |||||
Thermal ageing, cable insulator degradation, volume resistivity, elongation at break, and ethylene propylene rubber | |||||
Full Paper: PDF
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