Hitachi is carrying out an investigation after discovering that testing data on power equipment it had supplied to two Japanese nuclear power plants had been falsified.
The doubts centre on inspection record for heat-welded pipes in moisture separator heaters supplied for unit 5 at Chubu’s Hamaoka plant and for Chugoku’s Shimane-3, still under construction. Moisture separator heaters are not part of the nuclear reactor but are used to remove moisture from and reheat steam passing into power generation turbines, helping to improve the plant’s thermal efficiency.
According to Hitachi, doubts have surfaced over weld inspection data, which had been outsourced to another company, Japan Industrial Inspection Inc. It appears that data about temperature drops during the heat treatment process were not in line with expected standards. Some data also appears to have been erased from the records.
Hitachi has apologised for the “inconvenience to everyone concerned” and has said it is making efforts to prevent any recurrence.