摘要
某φ127mm G105钢质钻杆表面在服役过程中发生了严重的局部腐蚀。通过力学性能分析、宏观及微观腐蚀形貌观察,并结合能谱(EDS)和X射线衍射(XRD)等方法研究了该钻杆腐蚀失效的原因。结果表明:钻杆管体表面发生严重了点蚀且呈条带状分布;在钻杆管体和接头的过渡区也发生了严重的点蚀;引起点蚀的主要原因是氧腐蚀、Ca2+等离子引起的垢下腐蚀;氯离子的存在加速了钻杆的局部腐蚀。
Severe localized corrosion occured on the surface of a G105 steel drill pipe with a diameter of 127 mm during the service process. Mechanical analysis, micro and macro morphology observation, EDS and XRD were employed to invesitgate the failure reason of the drill pipe. The results indicated that severe pitting occurred on the external surface of the G105 drill pipe and upset transition area; and several stripped pits were observed obviously on the surface of the drill pipe. The pitting of the G105 drill pipe was attributed to the oxygen corrosion and under-deposit corrosion induced by carbonate deposits, such as calcium carbonate. The chloride ions accelerated the localized corrosion of the drill pipe.
出处
《腐蚀与防护》
CAS
北大核心
2016年第9期775-780,共6页
Corrosion & Protection
基金
中国石油集团大型油气田及煤层气开发项目
碳酸盐岩
火成岩及酸性气藏高效安全钻井技术课题(2011ZX05021-002)资助
关键词
钻杆
氧腐蚀
点蚀
失效分析
drill pipe
oxygen corrosion
pitting
failure analysis
