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The main influencing factors of high-temperature sulfur corrosion include temperature, medium flow rate, material alloy composition, sulfur content and material silicon content. These factors together determine the rate and severity of corrosion. temperature: is the key driver. Corrosion begins to occur significantly above 240°C, the rate reaches a peak at 420–430°C, and the corrosion rate decreases after exceeding 480°C. Medium flow rate: When the flow velocity exceeds 30 m/s, the protective FeS film formed on the metal surface is easily washed away and peeled off, leading to increased corrosion, especially in areas with sudden flow velocity changes such as elbows and tees. Material alloy composition: Increasing the chromium (Cr) element content can significantly improve corrosion resistance. For example, Cr-Mo steel and 300 series stainless steel (such as 304H) perform better in high-temperature sulfur environments. Sulfur content and active sulfur forms: The higher the content of active sulfur (such as H₂S, elemental sulfur) in the raw oil or gas, the more corrosive it is. Among them, elemental sulfur is the most corrosive, while thiophenes are more stable and less corrosive. Material silicon content: When the silicon content in carbon steel is less than 0.10%, the corrosion rate will be significantly accelerated. The Chevron refinery accident in 2021 is closely related to this factor. In addition, equipment design (such as avoiding eddy current structures) and process control (such as reducing flow rate, optimizing temperature distribution) are also important factors that can be controlled.