Nine reactors at five nuclear power plants in Japan 0have used products manufactured by the Kobe Steel group, Japan’s third-largest steelmaker, which has admitted fabricating product quality data. However, there are no immediate safety issues.
According to documents presented to a meeting of the Nuclear Regulation Authority (NRA), the operating reactors affected are Kansai Electric Power Co’s Takahama 3&4 in Fukui Prefecture and Kyushu Electric Power Co’s Sendai 1&2 in Kagoshima Prefecture. The others, currently offline, are Kansai Electric’s Ohi 3&4 in Fukui, Kyushu Electric’s Genkai 3&4 in Saga Prefecture, and Shikoku Electric Power Co’s Ikata 3 in Ehime Prefecture.
Kobe Steel’s welding rods were used during assembly work at all nine reactors, and reinforcing bars and parts in some reactor containment vessels use hexagon bolts manufactured by the company. The utilities told NRA that the products are not among those affected by the data fabrication scandal and, thus, pose no safety problems.
In October, Tokyo Electric Power Company reported that Kobe Steel welding rods with falsified inspection records had also been used for water tanks which are used to store contaminated water at the Fukushima Daiichi NPP. NRA Chairman Toyoshi Fuketa then asked for performance examinations to be conducted on the welding rods and asked nuclear operators to check whether they are using Kobe Steel products at nuclear plants.
Also in October, Japan Nuclear Fuel Ltd (JNFL) reported that Kobe Steel had supplied parts with false specifications for some of its nuclear equipment. The parts were destined for use in its centrifuge uranium enrichment plant under construction at its Rokkasho site. Kobe Steel had not told JNFL whether there are any safety issues with the parts, a JNFL spokesman said. A Kobe Steel spokesman told Reuters the company had fabricated data about specialised coatings used on the parts but had not identified any safety issues.