Failure Analysis of Water-Wall Tubes in the High-Pressure Boiler

Abstract:

In this case study, the corrosion failure analysis of high-pressure boiler water-wall tubes in a power plant was investigated by means of the chemical analysis, metallographic examination and scanning electron microscope (SEM) observation. Energy dispersive spectroscopy (EDS) was used to examine the changes of test materials and corrosion products. Based on the failure process of the boiler water-wall tubes and the experimental results, a conclusion was drawn that the failure of water-wall tubes was mainly caused by pitting corrosion. Sulfide and chloride attack was the major cause of localized pitting corrosion on the inner surface, and the outer surface damage was mainly due to the synergism of high temperature sulfide corrosion and flue gas erosion.

• Periodical: Advanced Materials Research (Volumes 912-914)
• Pages: 456-459
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.912-914.456
• Online since: April 2014
• Authors: Na Xu*, Jun Bo Shi, Yong De Li, Wei Min Guo, Xiao Feng Wu, Shu Xin Han, Qi Shan Zang, Zhi Wen Hu
• Keywords: Chloride, Failure Analysis, Pitting Corrosion, Sulfide, Water-Wall Tube

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