The repair process, which spans multiple days for each repair site, requires many steps, including site preparation, weld build-up application and numerous inspections. Each repair site is unique in its structure and accessibility and is therefore subjected to a lengthy qualification and examination process.
Following each repair, NDE, including two types of ultrasonic inspection and an eddy-current inspection inside the vessel, are required in order to confirm the quality of the repair. The inspection process is then followed-up with laser profiling of the vessel surface that has been welded. The purpose of this profiling is to quantify the thickness of the weld and confirm if there has been any shape change in the vessel due to the welding process.