Oct 31 Japan's 11 utilities said on Monday they had found no problems with mechanical resilience of forged steel used in important facilities at their nuclear plants such as reactor vessels.
Japan's nuclear regulator had ordered the investigation after France discovered that certain steam generator channel heads made by two different manufacturers - Areva's Creusot plant and Japan Casting & Forging Corp (JCFC) - could contain a zone comprising a high carbon concentration. That could weaken the mechanical resilience of the steel and its ability to resist the spreading of cracks.
The 11 utility companies, comprised of nine former monopolies such as Tokyo Electric Power and Kansai Electric Power, as well as Japan Atomic Power Co and Electric Power Development Co, all reported no possibility of high carbon concentration in their plants in statements. (Reporting by Osamu Tsukimori; Editing by Susan Fenton)