Derrick Retrofit: Weld Engineering and Esonix UIT Optimize Derrick Retrofit


A large multi-national offshore drilling company contacted Progress Rail's Ultrasonic Technology (UIT) Division seeking to improve the durability and reliability of a derrick structure. The original discussion focused on applying Progress Rail's UIT process to the derrick retrofit design; however, Progress Rail's engineering staff immediately recognized that Esonix UIT alone would not provide optimum results.


The customer agreed with the Engineering Services approach recommended by Progress Rail's Ultrasonic Technology (UIT) Division's engineering staff, and they engaged Applied Ultrasonics for the weldment design and to provide a full weld procedure which included application and quality control oversight of Esonix UIT. Applied Ultrasonics mobilized a team of weld engineers and technicians to the job site to provide weld QA/QC oversight as well as apply the Esonix UIT process per the approved specification.


The weld engineers developed an enhanced weld joint design as well as a welding procedure that efficiently incorporated Esonix UIT into the repair process.


The result of this successful partnership is a derrick structure that is more reliable due to vastly improved fatigue strength and fatigue life. This vessel is still in service today, and thanks to Progress Rail's Engineering Services, it will continue to perform for many years to come.




put uit to work