Applied Ultrasonics UIT resets fatigue life to ZERO and extends operation life by 15 years on Noble Ton van Langeveld Semi-Submersible Oil Rig

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 Noble 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, Noble 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 cracks on the welds treated with 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

Preventing Fatigue Failure with Ultrasonic Impact Treatment

The Devastating Effects of Fatigue Failure

Fatigue failure occurs when material is exposed to repetitive or fluctuating stresses that exceed its tensile strength threshold.  The effects are cumulative in their destructive potency, beginning as undetectable microscopic cracks that grow as they are continuously subjected to cyclic loading. 

Left untreated, seemingly insignificant fissures can grow to produce disastrous consequences, evidenced in such unfortunate cases as the Alexander L. Kielland oil platform disaster in 1980 and the midair disintegration of China Airlines Flight 611 in 2002.  And while not all outcomes of fatigue failure are as catastrophic, the breakdown of components greatly impact the operational capabilities of companies worldwide on a daily basis.  Ultrasonic impact technology (UIT) from Applied Ultrasonics has received mass recognition for its ability to successfully combat the contributing factors of fatigue failure throughout its stages of development.