Let’s discuss the causes of pipeline corrosion

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Corrosion refers to the chemical and electrochemical reactions between the surface of a metal material and the environmental medium, which lead to the degradation and destruction of the material. The common corrosion in oil pipelines is caused by corrosive substances present in crude oil, such as CO2, H2S, C1-, a small amount of dissolved oxygen, and bacteria; these substances react directly with the metal, leading to chemical corrosion. Chemical corrosion is not very harmful, while the main cause of bulges on the surface of steel pipes, leading to perforations, is electrochemical corrosion. When a metal undergoes an electrochemical reaction, the area with a lower electrode potential tends to lose electrons and becomes the anode ； The area with a higher electrode potential receives electrons and becomes the cathode. In the presence of O2 and H2O, Fe(OH)2 transforms into hydrated iron oxide, thereby causing corrosion.