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In this area, the tank wall is in direct contact with crude oil; the surface of the tank wall is wetted by the oil, resulting in a low corrosion rate. Therefore, tank wall corrosion and perforation accidents generally do not occur in the short term (20–30 years). However, at the interface between the gas and liquid phases, due to the differences in oxygen content in the crude oil and in the space above the oil surface, an oxygen concentration difference corrosion cell is likely to form; the greater the oxygen concentration difference, the higher the corrosion rate. Studies both domestically and internationally show that in steel storage tanks, if the crude oil contains no H2S, its service life is 10 to 15 years ； With H2S present, the lifespan is 3–5 years ； Moreover, corrosion perforation occurs preferentially at the bottom of the tank, with an average corrosion rate of 0.5~1.5 mm/year. Changes in the physical properties of crude oil have different effects on corrosion; when crude oil is heated to around 80°C, its viscosity decreases while at the same time its corrosiveness increases. The physical and chemical corrosion properties of crude oil were studied using the weight loss method, and it was found that at the same temperature, as the sulfur content in the crude oil increases, the corrosion rate tends to increase ； Below the critical temperature, as the temperature increases, sulfur activity rises and the corrosion rate accelerates ； When the temperature exceeds the critical temperature, the corrosion rate will no longer change and may even decrease.