Research on Stress Corrosion Behavior of In-Service Pipeline in H₂S Environment

Abstract:

Stress corrosion test of pressure vessels and piping in H2S environment has been explored extensively, but experimental research closed to the actual stress state of pipelines and the actual operating conditions, especially considered the combined effect of various factors is not common. Stress corrosion test simulated the actual operating conditions is taken in this paper. Four in-service pipes are researched as specimens and complex stress field is built by a specially designed loading device. Specimens are immersed in three different H2S concentration environments. The appearance and expansion of crack is observed regularly and the sensitivity of pipeline on stress corrosion is evaluated by metallographic examination. The result shows that: Intergranular corrosion, transgranular corrosion or micro-crack is not found in H2S corrosive solution (500×10-6, 800×10-6mg/L) after 2160 hours or in saturated H2S corrosive solution (greater than 2000×10-6mg/L) after 360 hours. A surface crack is found in H2S corrosive solution (500×10-6mg/L) after 720 hours and the expression for expansion rate of the crack during 2160 hours is a=16.835e0.0002h.

• Periodical: Applied Mechanics and Materials (Volumes 157-158)
• Pages: 1305-1312
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.157-158.1305
• Online since: February 2012
• Authors: Yan Li, Yi Liang Zhang, Guo Dong Jia
• Keywords: H₂S, In-Service Pipeline, Metallographic Observation, Stress Corrosion

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DOI: 10.1201/9780429273858-6