Failure Analysis and Protection of Oxygen Corrosion of Reheater Tube in a Power plant

Abstract

The failure analysis of reheater tubes were analyzed by means of alloy composition analysis, metallographic structure analysis, mechanical properties analysis and oxide composition analysis. The results showed: The alloy composition meets the requirements of 12Cr1MoV standard. No abnormality was observed in metallographic structure. Mechanical properties qualified. Oxide components are mainly O and Fe. Comprehensive analysis shows that The main reason of reheater tube failure is oxygen corrosion, which caused thinning of the reheater tube wall, leading to leakage accident. Suggestions for subsequent protection are put forward.