湿气管线内腐蚀直接评价方法的应用研究

摘要

In order to study the application effect of the internal corrosion direct assessment method for wet gas pipelines,a CO2-containing multiphase flow submarine pipeline in Yacheng is taken as an exam-ple to conduct the internal corrosion direct assessment. The NORSOK and the De Waard model are used respectively to do numerical simulation of the corrosion rate,and the predicting results of WG-IC-DA are validated by the final test results of the internal detection operation.The results indicate that the area of 116 corrosive defects predicted by indirect detection covers most of the corrosive locations found by magnetic flux leakage detection, and the corrosion distribution areas are basically the same, but the predicted corrosion depth is deeper than the actual corrosion depth;it is very important to choose suitable pipeline parameters during the prediction of corrosion rate, and parameters such as pressure, tempera-ture and gas flow rate have a great influence on the corrosion rate.Therefore,the WG-ICDA method has a guide role in the pipeline corrosion preventive management, and choosing appropriate corrosion rate prediction models and pipeline parameters can improve the accuracy of corrosion prediction.%为了研究湿气管线内腐蚀直接评价(WG-ICDA)方法的应用效果,以崖城某含CO2多相流海底管道为实例进行内腐蚀直接评价,分别使用NORSOK模型和De Waard模型对腐蚀速率进行数值模拟,基于内检测作业的最终检测结果对WG-ICDA的预测结果进行验证.结果表明:NORSOK模型更吻合流型影响下的湿气管道腐蚀速率变化规律;间接检测预测得出的116个腐蚀缺陷的区域涵盖了大部分漏磁检测发现的腐蚀位置,分布区域基本一致,但预测得到的腐蚀深度大于实际的腐蚀深度;在腐蚀速率预测过程中,管道运行参数的选取十分重要,管道的压力、温度、管内气体的流量等参数对腐蚀速率均有较大的影响.因此,WG-ICDA方法对于管道内腐蚀的预防性管理具有一定的指导作用,选择适合的腐蚀速率预测模型及管道参数可以提高腐蚀预测精度.