Failure of master link during subsea lifting operations

  • Safety Flash
  • Published on 8 July 2014
  • Generated on 23 October 2025
  • IMCA SF 11/14
  • 1 minute read

An incident has been brought to IMCA’s attention in which a master link (lifting ring) fitted to a 10t air lift bag failed in use during subsea lifting. This style of master links are also fitted to 10t water load bags.

Overall size of the master link

Overall size of the master link

Part number embossed on the flat section

Part number embossed on the flat section

Part number embossed on the flat section

Part number embossed on the flat section

What happened?

Unique Seaflex has identified the batch number of the parted master link. However, as these links are interchangeable, as a precaution, the company has decided to advise all owners or users of 10t air lift bags and 10t water load bags to inspect the master links fitted to their bags and quarantine any products marked with the following two possible lot numbers (which can be found embossed within the pressed section opposite the weld in the centre of one long side):

  • IWA
  • LWA

Members using 10t air lift bags or 10t water load bags fitted with a red master link marked IWA or LWA should contact Unique Group (info@uniquegroup.com) for further information in regards to ring change-out and replacement instructions.

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