Research on Internal Corrosion and Influence Factors of Petroleum Pipeline

Abstract

For slowing down the internal corrosion in crude oil pipeline, the failure mode, morphology and mechanism, as well as influence factors of internal corrosion in buried pipeline transporting purified crude oil were researched systematically. Results showed that the aqueous phase was deposited gradually in some locations during transport, and Cl - content could reach the maximum of 48 859.8 mg/L. In addition, the internal corrosion was mainly pitting and localized corrosion, and during the autocatalytic process of internal corrosion, the continuous migration of Cl - into the pits promoted the development of pitting corrosion, thus the Cl content at the pit bottom was higher than that at the surface by up to one order of magnitude. When the water content of the pipeline fluctuated in the range of 0.1% to 3.9%, the water content possessed little effect on the risk point of internal corrosion, and increasing the medium flow velocity had a more obvious effect on reducing the risk of internal corrosion. When the flow velocity increased to 2.00 m/s, the number of locations at risk of internal corrosion was reduced by 35.23% compared with that when actual flow velocity was 0.29 m/s.

Keywords

• l360 petroleum pipeline|internal corrosion mechanism|pitting corrosion|medium flow velocity