Corrosion Behavior of AISI 316L Stainless Steel Used as Inner Lining of Bimetallic Pipe in a Seawater Environment

Materials

Lei Jin¹  Wenlong Wang²  Daquan Li²  Huaping Xiao³  Qingjian Liu⁴ 

[1] China National Offshore Oil Corporation (CNOOC) (Tianjin) Pipeline Engineering Technology Co., Ltd., Tianjin 300461, China;China National Offshore Oil Corporation (CNOOC) China Ltd. (Zhanjiang), Zhanjiang 524057, China;College of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing 102249, China;Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin 300384, China;

关键词: bimetallic pipes;    corrosion cracking;    seawater simulated solution;    long-term corrosion tests;   

DOI  :  10.3390/ma14061539

来源: DOAJ

【 摘 要 】

Seawater leakage commonly leads to corrosion in the inner lining of submarine bimetallic pipes, with significant financial implications for the offshore oil and gas production industry. This study aims to improve understanding of the performance of bimetallic pipes by investigating the corrosion behaviors of mechanically bonded 316L stainless steel. Immersion experiments were conducted in a seawater environment, under both atmospheric conditions and high temperature and high pressure conditions, and corroded surfaces were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) to reveal micromorphology and elementary compositions. The results demonstrated that the corrosion rates of the bonded 316L specimen were between 5% and 20% higher than those of specimens without bonding under atmospheric conditions. This is attributed to the stress cracking that occurs during corrosion. Under high temperature and high pressure conditions, the corrosion rates were remarkably increased (91% to 135%) and the corrosion process took longer to reach equilibrium. This may be attributed, firstly, to the products becoming increasingly porous and weak, and also to the fluid stress caused by stirring in these experiments to simulate seawater movement.

【 授权许可】

Unknown