Reasons of Wellbore Corrosion in Yulin Gas Well

The whole life cycle condition of a gas well in Yulin was investigated, and the corrosion changes, corrosion rate and corrosion products of the wellbore were analyzed. The results show that as the depth of the well deepened, the damage in the upper part of the tubing was slight, the damage in the middle and lower parts was gradually increased, the damage of the lower tubing was obvious, the scale and corrosion coexisted, and the gas well tubing mainly underwent CO₂ corrosion. The corrosion products were mainly FeCO₃ and oxidized iron. Adding corrosion inhibitor could significantly slow down the corrosion rate of the wellbore.