ケーブル絶縁材の健全性診断に向けた非破壊検査システム開発（２）
概要
We reported previously the deterioration tendency of cable insulation materials used in nuclear power plants due to irradiation and the applicability of AE (Acoustic Emission) digital hammering inspection to detect the deterioration nondestructively by comparing the natural frequencies before and after the irradiation. In this study, we selected two kinds of triple core cables which are often utilized in nuclear power plants. The natural peak frequency increased due to the increase of irradiation dose, and showed the same tendency as the single core cable in our previous report. Moreover, we carried out the tensile test on the insulation and confirmed that the amount of change in the peak frequency and Young's modulus had positive correlation. It was therefore suggested that the deterioration of the cable insulation can be detected by AE hammering inspection for even more complex triple core cables.
