提出了一种适用于海上油田海底管道多相流内腐蚀直接评价（ICDA）方法；基于海底管道基础数据、生产工况以及油气水检测数据，对介质流态的热力学、动力学和水力学影响因子进行分析，评估海管内腐蚀发生的位置及最大局部腐蚀速率；将南海多条海管的直接检测数据与ICDA结果进行对比。结果表明：ICDA评估方法能够准确地反映海管实际内腐蚀状况，为不能采用智能通球FML内检测的海管提供了一种有效的内腐蚀评估方法。

A multiphase flow internal corrosion direct assessment (ICDA) method for subsea pipeline of offshore oil field was proposed. The influence factors for thermodynamics, dynamics and hydraulics of flow states were analyzed synthetically based on the basic data of subsea pipeline, production conditions and the inspection data of oil, gas and water. The location of the occurrence of internal corrosion and the maximum corrosion rate of localized corrosion were assessed. And Data from direct testing for subsea pipelines in the South China Sea and from ICDA method were compared. The results show that ICDA method could accurately detect the internal corrosion in subsea pipelines, providing a valid method of internal corrosion assessment for the subsea pipeline which is not suitable for intelligent pigging MFL internal inspection.