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The corrosion environments in oil production and transportation systems are complex and diverse, and can be mainly divided into three core scenarios, each with distinct corrosion characteristics: First, soil corrosion – buried transportation pipelines remain in the soil environment for extended periods; the air, moisture, and dissolved salts in the soil pores create an electrolytic environment, leading to electrochemical corrosion due to the depolarizing effect of oxygen. The degree of its corrosion is influenced by factors such as soil porosity, moisture content, resistivity, pH value, salt content, stray currents, and microorganisms like sulfate-reducing bacteria. II. Corrosion caused by produced water: After water injection in oil fields, the water content in the produced fluid increases significantly. Corrosive substances present in this water, such as dissolved oxygen (a concentration of less than 0.1 mg/L is sufficient to cause corrosion of carbon steel), hydrogen sulfide, high concentrations of chloride ions, and sulfate-reducing bacteria, combined with factors such as water temperature, flow rate, and cavitation erosion, can cause severe electrochemical corrosion to the downhole piping and transportation pipelines. In some oil fields with high salinity, the Cl⁻ concentration can exceed 100,000 mg/L, thereby greatly increasing the risk of local corrosion, according to international academic research. III. Atmospheric corrosion: Although it is not the primary form of corrosion, equipment and pipeline steel structures that are exposed to the atmosphere in such systems can develop a thin conductive liquid film in the humid and salty atmospheric conditions of oil fields, leading to atmospheric corrosion. This can be prevented through the use of surface coatings and improved design strategies.