Certification Authentication

Occasionally, DNV GL determines that the conditions of the certificate’s for materials and components have been violated or that operating experience confirms that the product does not function as intended and/or required.  In such cases DNV GL has the prerogative to suspend or withdraw the certificate, see DNVGL-RU-SHIP Pt.1 Ch.1 Sec.4 [3]. Below you can find a list of recently suspended or withdrawn certificates.

Recent cases:

Certificate No.CompanyProductLink to approval finder
AMMM0000053 Rev.1Henan Mingtai Al.Industrial Co.,Ltd. Gongyi, Henan, ChinaWrought Aluminium and Aluminium AlloysSearch | Approval finder
AMMM00002RAHenan Mingtai Al.Industrial Co.,Ltd. Gongyi, Henan, ChinaWrought Aluminium and Aluminium AlloysSearch | Approval finder


Details to the above listed cases: 

DNV GL certified aluminium plates of grade VL5083, manufactured by Henan Mingtai Industry Co., Ltd., China (Mingtai) in 2020, have been confirmed sensitized. The certification was based on satisfactory ASTM G66 and ASTM G67 tests as documented by the manufacturer, but the recently confirmed sensitization gives reason to believe that the corrosion testing at the manufacturer may have been incorrect. So far 10-15% of the retested batches have failed to meet the requirements to weight loss as specified in G67 and some batches have failed to meet the requirements in G66. All batches that have failed to meet G67 requirements are delivered temper H116 and are of thickness 5 or 6 mm.  The manufacturer has so far not provided a root cause but committed to additional corrosion testing. Until retesting has been completed, or a satisfactory root cause have been identified, the manufacturer certificates for the materials, endorsed by DNV GL, are suspended. For further details please contact the manufacturer.

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