Kobe Steel Ltd. said Sunday inspection data was fabricated on some of its aluminum and copper products shipped to about 200 companies and the systematic misconduct started 10 years ago at factories.
While Kobe Steel did not disclose the names of the companies affected, aluminum products supplied with fabricated data were found to have been used in vehicles made by Toyota Motor Corp. and Mitsubishi Regional Jet passenger planes, which are currently being developed by a subsidiary of Mitsubishi Heavy Industries Ltd.
Kobe Steel said inspection data, such as on the strength of the products, were rewritten when customer specifications were not met.
Kobe Steel Executive Vice President Naoto Umehara said workers were “feeling pressure” to meet the deadlines to deliver the products, but denied that data fabrication was ordered by senior management.
The company checked products shipped over the past year and found data fabrication in about 19,300 tons of aluminum products, 2,200 tons of copper products and 19,400 pieces of aluminum forging and casting products.
An official of Mitsubishi Heavy said the aluminum products in question are unlikely to have safety problems and that the development of Mitsubishi Regional Jet will not be affected. The aircraft will be Japan’s first domestically developed jet airliner, although its delivery schedule has been repeatedly pushed back.
Toyota said it used the aluminum products in some car parts such as hoods. The company is investigating which models were involved and the impact of using the products.
Kobe Steel said it recognized the data fabrication in late August, but did not make it public until told to do so by the Economy, Trade and Industry Ministry.
The ministry has ordered Kobe Steel to conduct an investigation into the practice.
According to Kobe Steel, data fabrication was found at all its aluminum product factories in Tochigi, Mie and Yamaguchi prefectures, as well as at a subsidiary’s copper product factory in Kanagawa Prefecture.
Data fabrication involving its group stainless steel products was revealed last year.