37Mn5钢石油输油管穿孔失效分析

Perforation Failure Analysis of 37Mn5 Steel Oil Pipeline

某石油化工厂输油管道使用过程中发生穿孔失效现象。采用宏观、微观检验、化学成分分析及压扁试验等方法,对失效管件进行了检测。结果表明管件表面大量的非金属夹杂物与基体形成原电池,继而发生电化学腐蚀,形成显微腐蚀点。这些腐蚀点成为凹坑形成的原因,在应力作用下,这些显微腐蚀点会继续进行应力腐蚀,直至穿孔管道穿孔失效。

The oil pipeline of an oil chemical plant occurred perforation failure phenomenon during using. The failure tube was tested by macro and micro examination, chemical composition analysis ,flattening test etc.. The results show that a large number of nonmetallic inclusions on the pipe surface form galvanic cell with the substrate, which occurs then electrochemical corrosion and forms micro corrosion pits. The corro- sion pits become the cause forming pits, and under the action of stress, these microscopic corrosion pits will keep the stress corrosion until the perforated pipe into the perforation failure.