Analysis on Backside Cracks in 316LMod Inner Linings of Urea Reactors

Abstract:

Backside cracks were found universally in the ultra-low carbon austenitic stainless steel (316LMod) inner linings of urea reactors in recent years, and led to urea reactors leakage. Analyses on the sample revealed that, the backside cracks were caused by the interaction of wet hydrogen sulfide (H₂S) and chloride ions (Cl^-) stress corrosion cracking (SCC), and H₂S played a dominant role. The source of H₂S and chloride ions was the leak detection steam. Furthermore, measures to avoid backside cracks in 316LMod inner linings of urea reactors were put forward and verified.

• Periodical: Applied Mechanics and Materials (Volumes 184-185)
• Pages: 858-863
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.184-185.858
• Online since: June 2012
• Authors: Huai Xiang Cao, Chun Mao Wang, Xing Qi Qiu
• Keywords: 316LMod, Backside Cracks, Inner Lining, Stainless Steel (SS), Stress Corrosion Cracking (SCC), Urea Reactor

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