Failure Analysis of TP347H Pipe for High Temperature Superheater in Power Plant

This article analyzes a TP347H pipe explosion accident that occurred in a 600 MW boiler high-temperature superheater. The study revealed through macroscopic inspection, thickness testing, spectral analysis, metallographic examination, and scanning electron microscopy that the large precipitation of the $\sigma$ phase in the austenite structure due to long-term local overheating reduces the creep resistance of stainless steel and produces creep pores and cracks, ultimately leading to pipe leakage. Therefore, this topic aims to accurately summarize the content of the paper, highlighting the main findings and research focus, namely the influence of local overheating and $\sigma$ phase precipitation on the performance of TP347H pipes, and how these factors lead to the failure of superheaters.