油田20号钢弯头的失效原因  

Failure Reason of 20 Steel Elbow in Oilfield

作　　者：朱凯峰 苏锋[1] 崔鹏[1] 李轩鹏 ZHU Kaifeng;SU Feng;CUI Peng;LI Xuanpeng(Dagang Oilfield Production Technology Research Institute,China National Petroleum Corporation,Tianjin 300280,China;State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials of CNPC Tubular Goods Research Institute,Xi'an 710077,China)

机构地区：[1]中国石油天然气股份有限公司大港油田分公司采油工艺研究院,天津300280 [2]中国石油集团石油管工程技术研究院石油管材及装备材料服役行为与结构安全国家重点实验室,西安710077

出　　处：《腐蚀与防护》2023年第4期107-112,118,共7页Corrosion & Protection

基　　金：中石油超前储备项目(2020Z-07);宁波市科技创新2025重大专项(2020Z108)。

摘　　要：通过理化性能检测、组织分析、腐蚀形貌、产物膜分析、流体和冲刷腐蚀数值模拟等手段,并结合现场服役工况,系统分析了某油田20号钢弯头短期内3次腐蚀穿孔的原因。结果表明:CO_(2)吞吐过程导致弯头部位出现CO_(2)腐蚀,生成的腐蚀产物膜疏松多孔,同时介质中固体颗粒的存在导致弯头外弧侧出现冲刷腐蚀。在CO_(2)腐蚀和冲刷腐蚀的共同作用下,弯头外弧侧FeCO3产物膜破坏,金属基体裸露,外弧侧壁厚迅速减薄最终发生穿孔。最后,给出了避免或减缓此类弯头失效的建议。On the basis of the service environment,the reasons of 20# elbow 3 times failure in a short period were investigated by means of physical and chemical property testing,microstructure analysis,corrosion scale analysis,flow rate and erosion corrosion simulated results.The results indicated that CO_(2) corrosion occurred at the elbow during the process of CO_(2) huffing and puffing,and the loose and porous FeCO_(3) corrosion scale formed.Meanwhile,the solid particles in the medium caused erosion corrosion on the outer arc side of the elbow.Under the synergistic effect of CO_(2) corrosion and erosion corrosion,the FeCO_(3) scale was destroyed,and metal was exposed on the outer arc side of the elbow,resulting in a rapid thinning of the outer arc sidewall and finally perforation.Finally,suggestions were given to avoid or slow down the rapid failure of such elbows.

关 键 词：20号钢 弯头 腐蚀穿孔 冲刷腐蚀 CO_(2)腐蚀 

分 类 号：TG174[金属学及工艺—金属表面处理]