Abstract
This paper shows the temperature distribution of a hydraulic generator using the thermograph camera, and thermal aging test results of the rubber seals in the hydraulic generator to extend the overhaul interval. In the temperature observation of the hydraulic generator, the temperature distribution was observed 4 times in a year, and it was forecast that the upper part of the bearing cover of water turbine and the lower part of generator cover were parts where the heat deterioration was promoted most. In thermal aging tests of rubber seal, the permanent strain of rubber seals were evaluated on 90℃, 105℃ and 120℃. The time when the rubber seal shows 80 and 90% permanent strain on 50℃ was estimated as 3.2 and 11.7 years respectively.
