In May 2007, Applied Ultrasonics treated 82 welds on 12 critical column bracing connections on the rig; GustoMSC, a leading offshore engineering firm, conducted a detailed fatigue analysis for the client and determined these connections would fail in the next 15 years…
The shipyard works took two weeks with two crews to complete. After UIT treatment, GustoMSC determined the fatigue life of the connections were reset to zero and ABS granted a 15-year life extension for the rig to continue operations in the North Sea.
In September 2010, the client performed the inspections required for 5-year special survey (done a year early due to contract timing). They did an underwater in lieu of dry dock (UWILD) inspection and found ZERO corrosion cracking on post weld treatment using UIT. The rig resumed contract in December 2010, garnering a competitive day-rate for a North Sea rig of its class.
Original post: http://appliedultrasonics.com/news.html#-1