某海上油田海水系统青铜阀门腐蚀穿孔原因分析

某海上油田海水系统发生泄漏,经调查为某青铜截止阀腐蚀穿孔所致。针对此截止阀腐蚀失效开展了宏观分析、理化性能检验、扫描电镜(SEM)及能谱(EDS)分析、X射线衍射(XRD)分析等。结果表明:铸造加工缺陷导致材料耐蚀性降低是导致阀门腐蚀穿孔的主要原因;阀门穿孔位置遭受较严重冲刷腐蚀,是导致弯头腐蚀穿孔次要原因。建议今后对新购进青铜铸造构件加强质检,确保质量和耐蚀性合格,优化此类阀门结构设计,避免阀体局部遭受严重冲刷腐蚀。

Analysis on Causes of Corrosion Perforation in Bronze Globe Valve of Certain Offshore Oil Field Seawater System

Leakage occurred in certain offshore oilfield seawater system,which is caused by corrosion perforation of the bronze globe valve through investigation.The failure cause of the corrosion perforation in globe valve was studied by macro analysis,physical and chemical properties test,SEM & EDS,XRD analysis and so on.Results showed that the defects formed during the casting process reduced the corrosion resistance of the valve material,which was the main reason of the leakage.Meanwhile the perforation area suffered serious erosion corrosion,which was the secondary reason.Consequently,it was suggested to perform quality inspection on the newly purchased bronze valve components to ensure quality and corrosion resistance,and meantime to optimize the design of valve to avoid local erosion-corrosion.