DNV GL and Subsea Global Solutions LLC. (SGS) announced the completion of an extensive joint research and development program that allows permanent repairs to be carried out by underwater wet welding on certain areas of vessels.
With DNV GL’s approval, SGS will be available to perform permanent repairs on a case-by-case basis utilizing this procedure in suitable locations.
Over the last two and a half years, SGS welded in excess of 80 groove weld test plates underwater at depth in their training facilities in Miami, Florida, Long Beach, California and Terneuzen, the Netherlands. The non-destructive and mechanical testing of the plates was performed at DNV GL’s lab in Hamburg, Germany. All data collected was shared between SGS and DNV GL during this procedure development program.
At the end of April 2014, test plates were welded in the training tank in Miami Florida, with a DNV GL welding engineer in attendance. The non-destructive and destructive testing was again performed at the DNV GL lab in Hamburg. Welding of the plates as well as non-destructive and destructive testing was performed in accordance with AWS D3.6M:2010 Class A. The results of the non-destructive and destructive testing were very positive with all welded test plates exhibiting metallurgical properties equivalent to permanent weld repairs performed “top-side” dry.