酸性气田管道防腐内涂层性能检测评价

Performance evaluation of anticorrosion inner coating on sour gas field pipeline

关键词:  酸性气田  气液混输  内腐蚀  内涂层  穿孔

Key words:  sour gas field  gas-liquid mixed transportation  inner corrosion  inner coating  corrosion perforation

摘要:

川渝气田某酸性气液混输管线近年多次发生内腐蚀失效,为此,将该条管线采用环氧酚醛内涂层防腐。在防腐内涂层服役1.5年之后,为了研究内涂层在酸性气田集输管线上的适应性,对该防腐内涂层开展了实验室评价。对现场获取样品分别进行内涂层的外观、厚度、硬度、耐冲击、附着力、耐磨性等性能指标测试。实验结果表明,服役1.5年后,内涂层的硬度、耐冲击、附着力3项力学性能指标良好,但部分样品的厚度与耐磨性则出现了明显的降低。总体来看,该涂层在短期内较好地抑制了管线内腐蚀速度,但仍需要在后续工作中定期掌握在役涂层耐磨值、厚度的变化情况,同时对管线内腐蚀情况进行腐蚀监测,进而评价该涂层在酸性腐蚀介质中长期服役的可行性。

Abstract:

The internal corrosion failure of a sour gas-liquid mixed transportation pipeline often occurred in Chuanyu gas field in recent years. Therefore, this pipeline was protected by epoxy phenolic inner coating. After 1.5 years of anticorrosion inner coating, in order to study the adaptability of epoxy phenolic coating in sour gas gathering pipeline environment, laboratory evaluation of the in-service anticorrosion inner coating was carried out. At first, the pipeline was sampled on site, and then the properties of internal coating such as appearance, thickness, hardness, impact resistance, adhesion and wear resistance were tested. The experimental results showed that the mechanical properties of the coating such as hardness, impact resistance and adhesion were good after 1.5 years of service, but the thickness and wear resistance of some samples were obviously reduced. Overall, the coating inhibited pipeline inner corrosion in a short time, but still needs to regularly evaluate the thickness and wear resistance of the coating in the follow-up work, at the same time corrosion monitoring should be carried out to evaluate the long-term service feasibility of the coating in sour corrosive medium.