Chapters authored
Failure Analysis of High Pressure High Temperature Super- Heater Outlet Header Tube in Heat Recovery Steam Generator
Heat Recovery Seam Generator (HRSG) tube failure is one of the most frequent causes of power plant forced outage. In one of the local power plants, one of the boilers has experienced several defects and failures after running approximately 85,000 hours. 17 tube failures were found at the High Pressure High Temperature Superheater (HPHTSH) outlet header. The aim of this study is to find the root cause of the tube failures and to suggest the remedial action to prevent repetitive failure event. Several analysis methods were conducted to ascertain the potential cause(s) of failure. The results showed that the tubes failed due to long-term creep and thermal fatigue based on the cracking behaviour. Furthermore, the power plant has been operating as a peaking plant which concluded that the tubes have undergone the thermal stress due to frequent temperature change in the tubes. Flow correcting device (FCD) was also found damaged, causing flow imbalance in the tubes. Flow imbalance accelerated the creep degradation on the tubes. It was recommended that the FCD has to be repaired and improved to balance the flow. Furthermore, the extensive life assessment was recommended to be done on all the tubes to avoid future tube failures.
Part of the book: Failure Analysis and Prevention