Corrosion Behavior of Oil Casing Materials Used Commonly in Thermal Production Well in Acid Medium

The corrosion behaviors of different oil casing materials were studied in corrosion test under simulated working conditions, at the same time the data analysis was conducted with corrosion prediction software. The results show that uniform corrosion rates of N80, BG80-3Cr, P110 and BG90H at 50 ℃ and 150 ℃ were higher than 0.2 mm/a, the four materials corroded seriously. In the experimental temperature range， BG90H-9Cr and BG90H-13Cr had good resistance to uniform and localized corrosion in CO2+H2S+O2 media. The effect of temperature on corrosion of oil casing steel was more complicated. With the increase of temperature, the corrosion rate rose first, and then declined at relatively high temperatures because corrosion product films generated on the surface of metal materials.