Evaluation of the Effects of Dissolved CO₂ Gas on the Corrosion Rate of API 5L X60 Steel Crude Oil Pipelines, Considering the Effect of Vibration

Abstract

Vibrations in crude oil pipelines can occur due to the flow of crude oil, pumps, wind, earthquakes, and human activities. When vibrations are combined with corrosive environments and dissolved gases, especially CO₂, they can accelerate corrosion and ultimately lead to failure. In this study, a novel vibration immersion test was conducted in the laboratory under various temperatures and low CO₂ dissolved gas pressures to investigate the corrosion rate in API 5L X60 steel pipelines. The experimental 1991 De Waard-Lotz-Milliams correlation and a neural network method were used to evaluate the effects of CO₂ gas levels on overall corrosion rates. The results indicate that temperature, CO₂ partial pressure, and vibration directly influence corrosion rates. The corrosion rate increases uniformly at constant vibration and CO₂ partial pressure as temperature rises, exceeding 1%. At constant vibration and temperature, corrosion rates increase uniformly by less than 1% with increasing CO₂ partial pressure.