目的 通过研究美国腐蚀工程师协会（NACE）于2016年提出的适用于多相流管线的内腐蚀直接评价标准SP0116-Multiphase flow internal corrosion direct assessment methodology for pipelines（以下简称MP-ICDA），探究该评价方法在国内的现场应用步骤，为国内内腐蚀直接评价方法提供参考。方法 以我国东海某海底管线的实际运行工况为基础，建立Norsok M506内腐蚀预测模型，利用流体动力学理论，模拟分析管线内腐蚀状况，结合评价标准的预评价、间接检测、详细检查及后评估四个步骤进行内腐蚀直接评价。结果 管线整体内腐蚀速率超过0.25 mm/a，腐蚀程度较严重。管道1.5~2.5 km低洼处及两侧立管处腐蚀速率明显增大，其腐蚀高危点与段塞流动状态、高持液率等流动参数有关。现场在线检测数据与模型预测结果基本一致，由此证明了模型的可靠性。根据腐蚀程度等级及标准规定的内腐蚀再次评估周期，确定管线再评估时间间隔为1年。结论 ICDA能够准确预测管线内腐蚀状态与风险大小，为无法实施内检测的管线提供了有效的内腐蚀评估方法，其对预测多相流管道腐蚀发生的位置与风险等级具有一定的指导作用与借鉴意义。流体的动力学参数对腐蚀速率影响较大，应用MP-ICDA方法时应选取合适的内腐蚀预测模型及管线运行参数。在海底管线正常运行期间，可对ICDA的结果进行多次循环校核，从而提高腐蚀预测的准确程度。

The work aims to study internal corrosion direct assessment standard proposed by National Association of Corro-sion Engineers (NACE) for multiphase flow pipeline: SP0116-Multiphase flow internal corrosion direct assessment methodology for pipelines (here in after referred to as MP-ICDA) and explore the application steps of this method in the domestic field, so as to provide some reference for the domestic internal corrosion direct assessment method. Norsok M506 internal corrosion predictive modeling was established based on the actual working conditions of the pipeline in the east sea in China to simulate and analyze the internal corrosion conditions of pipeline through the hydrodynamics theory. The internal corrosion direct assessment was carried out by four steps: pre-assessment, indirect inspection, detailed examination and post-assessment. When the whole internal corrosion rate of pipeline was greater than 0.25 mm/a, the corrosion degree was serious. The corrosion rate of low-lying part at 1.5~2.5 km and the inlet and outlet risers increased obviously. The high risk points of corrosion were related to the flow parameters such as slug flow state and liquid holdup. The on-line detection results were basically consistent with the model prediction results, thus proving the reliability of the model. According to the level of corrosion and the standard period of re-assessment of the internal corrosion, the pipeline re-assessment interval was one year. ICDA method can accurately predict the condition and risk of corrosion and provide an effective method of internal corrosion assessment for subsea pipeline not suitable for internal inspection. It has a certain guiding effect and reference significance for the prediction of the location and risk level of corrosion in multiphase flow pipelines. The kinetic parameters of the fluid have great influence on the corrosion rate. When the MP-ICDA method is adopted, the appropriate internal corrosion prediction modeling and pipeline operating parameters should be selected. During the normal operation by subsea pipeline, ICDA can be checked for several times to improve the accuracy of corrosion prediction.