| Appearance | Observation | Locations | Mechanism | |
|---|---|---|---|---|
|
sharply defined hole | Holes, Pits, Gouges » Waterside | Economizer | Corrosion Fatigue |
|
Thinning on inside of a U-bend or other change in direction | Holes, Pits, Gouges » Waterside | Economizer | Flow Accelerated Corrosion (FAC) |
|
Multiple cracks associated with attachment on outside of tube | Cracking » In or near weld or attachment » Longitudinal or Random | EconomizerWaterwall | Corrosion Fatigue |
| Appearance | Observation | Location | Mechanism |