双金属复合管环焊缝耐蚀性能评价方法

Corrosion resistance evaluation method of bimetallic composite pipe girth weld

关键词:  双金属复合管  环焊缝  耐蚀性能  高酸性气田 

Key words:  bimetallic composite pipe  girth weld  corrosion resistance  high acid gas field

摘要:

目的 建立双金属复合管环焊缝耐蚀性能评价方法,为双金属复合管在高酸性气田现场应用提供依据。方法 针对双金属复合管环焊缝在高酸性环境中的主要腐蚀类型,参考标准Q/SY 06018-2016中冶金复合管直焊缝和堆焊层腐蚀评价内容,确定以晶间腐蚀、抗SCC/SSC性能、点腐蚀、模拟工况腐蚀为评价指标,并通过整管段试验验证评价结果的双金属复合管环焊缝耐蚀性能评价方法,同时以国产L360/825冶金复合管环焊缝为例对建立的评价方法进行验证。结果 通过使用建立的方法对L360/825双金属复合管环焊缝耐蚀性能进行评价,验证了评价方法有效可靠,评价结果显示L360/825双金属复合管环焊缝具有良好的耐蚀性能。结论 建立的评价方法可以直接应用于高酸性气田用双金属复合管的环焊缝耐蚀性能评价,为双金属复合管的现场应用提供依据。 

Abstract:

Objective The aim is to establish a method of evaluating the corrosion resistance of bimetal composite pipe girth weld, and provide a basis for the field application of bimetal composite pipe in high acid gas field. Methods In view of the main corrosion types of bimetallic composite pipe girth welds in high acid environment, the intergranular corrosion, SCC/SSC resistance, point corrosion and corrosion under simulated condition were determined as evaluation indexes by referring the standard Q/SY 06018-2016 Corrosion evaluation contents of straight weld and surfacing layer of metallurgical composite pipes. The method was verified through the whole pipe section test, and the domestic L360/825 metallurgical composite pipe girth weld was taken as an example to verify the method. Results The method was used to evaluate the corrosion resistance of the girth weld of L360/825 bimetal composite pipe, and the evaluation method was validated to be effective and reliable. The evaluation results showed that the girth weld of L360/825 bimetal composite pipe had good corrosion resistance. Conclusion The method can be directly applied to the evaluation of girth weld corrosion resistance of bimetallic composite pipe used in high acid gas field, which provides a basis for the field application of bimetal composite pipe.