#ndt Heat recovery steam generators (HRSGs) are susceptible to various degradation mechanisms—Flow Accelerated Corrosion (FAC), pitting and fatigue cracking. In order to harvest maximum heat from the exhaust gas, thousands of tubes are stacked together with narrow gaps between tubes. The compact design imposes access restrictions for inspection and repair. Failures are often unpredicted, resulting in undesirable, forced outages.
In this paper, they describe a technique to internally inspect HRSG fi