Investigation of the failure of High-temeperature Super Heater Headers in the Boiler of a Power Plant Using Experiments and Numerical Simulation

Authors

Abstract

After years from the first day of operating a power plant, it has been seen that the pipes of the high-temperature super heater suffer from damage and failure. In-depth investigations have revealed that the damage has occurred suddenly and remained heavy ruining instrumentations and buildings. Experiments and finite-element numerical simulations are conducted to understand the risk factors. The experiments such as gas flue analysis, hardness test for both intact and damaged tubes, the morphology of the failure part, and the analysis of the sediment inside the tubs are done. The main reasons for the failure of the super heater unit are found to be: striking hot flue gases with temperature of 530° Celsius and the stress of thermal elongation of the tubes .With the obtained results, some remedies such as using soot removal systems, using high-quality fuels, modifying combustion systems for applying fuels out of design, and using adjustable burners can be presented to solve the aforementioned problems. The current results can be valuable for other researchers to prohibit similar phenomena.

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