Corrosion Mechanism of the Stationary Section of L320 Crude Oil Pipeline

The static section of a corrosion perforated L320 oil pipeline was selected as the research object. The corrosion causes of the stationary section of the crude oil pipeline were studied through field investigation, physical and chemical testing and electrochemical methods. The results show that the service environment of the stationary section of the crude oil pipeline was mainly oil-water mixed medium containing H₂S, CO₂ and mineral compounds. Corrosion failure was mainly concentrated on the 5 to 7 o'clock position on the inner wall of the pipeline. The corrosion product was loose and contained S, O, C, and Fe elements. The dominant factor of failure was localized corrosion caused by crude oil deposited water containing H₂S and CO₂. In addition, the loose corrosion products had the effect of accelerating corrosion, and the corrosion morphology was also changed from localized corrosion to uniform corrosion.