Cause Analysis of Plate Pitting Corrosion in Lubricating Oil Cooler of Main Equipment in Datang Weihe Thermal Power Plant

Abstract:

The plate heat exchanger in oil cooler of unit 2 in a thermal power plant became corrosion perforation after 2-year running, and severe pits were found on its surface. The material and scale composition of the lubricating oil cooler was analyzed, and it was found that the oil cooler was made of 304 stainless steel, instead of the 316 stainless steel provided by factory. The corrosion products on the corroded surface were composed of some characteristic elements in cooling water. The analysis suggested that the reason for corrosion perforation of the heat exchanger could be associated with its material composition, and the under scale corrosion formed under the action of scale deposition could also cause corrosion perforation and large-scale pits.

• Periodical: Advanced Materials Research (Volumes 634-638)
• Pages: 1677-1681
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.634-638.1677
• Online since: January 2013
• Authors: Zhou Ping Li, Xiao Jian Hu, Hai Yan Ma, Si Wei Yan, Ai Jun Yan, La Jun Feng
• Keywords: Corrosion under Scale, EDS, Oil Cooler, SEM, Stainless Steel (SS)

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