Abstract: CO₂ is one of the key factors that causes serious corrosion of petroleum equipment and facilities. Aiming at the problem of serious pitting corrosion in the impeller of oil pump in CO₂ flooding field, the corrosion rate, corrosion morphology and potential are analyzed comprehensively in this paper. The results show that the corrosion rate of FV520B steel increases exponentially with the increase of pipeline transport pressure and flow rate (R²>0.9), and the potential shifts negatively. With the increase of pipe pressure, the corrosion directivity of the specimen surface gradually disappears, indicating a distinct pitting area and a comprehensive corrosion area. With the increase of flow rate, the metal surface presents a grooved erosion morphology with small pits. This is due to cavitation under high pipe pressure and flow rate conditions.

Key words: crude oil containing CO₂, impeller of oil pump, erosion corrosion, cavitation