Effect of Chemical Composition and Microstructure Parameters on Carbon and Low-Alloy Steel Corrosion Resistance Under Oil Industry Pipeline Operation Conditions

Abstract

The effect of chemical composition and microstructure parameters on corrosion resistance of carbon and low-alloy steels in neutral aqueous media, typical for oil-field pipeline operating conditions, is studied in order to develop requirements for the specified characteristics to improve steel equipment service life. It is shown that a large amount of interfacial nano-sized precipitates in steel, (even with sizes of 2–3 nm or less) mainly of vanadium carbide (carbonitride), and to a markedly lesser extent with niobium carbide, is present. A significant reduction in the corrosion resistance of steel due to the formation of such particles is observed with an increase in the vanadium content in steel more than 0.065–0.07%.