(V) Failure Analysis of a Process Natural Gas De-Superheater

Failure of a process natural gas (PNG) de-super heater line in a methanol plant was investigated utilizing different characterizing techniques including optical light microscopy, scanning electron microscopy, and chemical analysis techniques, to determine the failure mechanism, and contributing factors. The investigation showed that the line failure is attributed to thermal fatigue. The investigation showed also the presence of corrosive species inside the line which could have contributed to the failure. Practical corrective actions were suggested in order to avoid reoccurrence of similar failures.