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I. Judgment based on typical corrosion characteristics – Macroscopic morphological features: Local pitting, ring-shaped corrosion, and platform-type corrosion may appear on the pipe surface. Among these, platform-type corrosion is the most severe form of CO₂ corrosion, as it can rapidly lead to thinning of the pipe wall or even perforation. Characteristics of corrosion products: The corrosion products are primarily composed of ferrous carbonate (FeCO3); they are dark brown in color and have a loose texture. In some areas, the coating of these products is uneven, which leads to the formation of autocatalytic corrosion couples that accelerate local damage. II. Confirmation through testing methods: Investigate the conditions at the site and examine the environment in which the pipes are located. If the moisture content of the medium exceeds 200 ppm, the temperature is between 60–110°C, and the CO₂ partial pressure is greater than 0.21 MPa, it falls within the range where CO₂ corrosion is likely to occur, resulting in a significantly increased risk of corrosion. Precise laboratory testing is carried out by using an autoclave to simulate actual operating conditions; the corrosion rate is calculated through mass loss analysis, while SEM and XRD are employed to analyze the composition and morphology of the corrosion products, thereby allowing for an accurate determination of whether CO₂ corrosion is present.