DNV GL and Subsea Global Solutions (SGS) have announced the completion of an extensive joint research and development program that will allow permanent repairs to be carried out by underwater wet welding on certain areas of vessels.
The approval comes following an extensive period of testing. Over the last two and a half years, SGS welded in excess of 80 groove weld test plates underwater and at depth.
These tests were performed in training facilities in Miami and Long Beach, USA, as well as Terneuzen in the Netherlands.
Following these underwater tests, non-destructive and destructive testing of the plates was then performed at DNV GL's lab in Hamburg, Germany. All data collected was shared between SGS and DNV GL during this procedure development program.
In early April this year, a final test plate was welded in a training tank in Miami with a DNV GL welding engineer in attendance. A round of follow-up testing was then performed in Hamburg, with the results deemed "very positive".
According to DNV GL, all of the welded test plates exhibited metallurgical properties equivalent to, "permanent weld repairs performed topside dry".