ABSTRACT
Corrosion damage is one of the causes of downhole tubular column failure, and its reaction process is influenced by factors such as ambient temperature, pressure, medium concentration and flow velocity. In order to study the corrosion pattern of P110 steel pipe wall in flowing liquid environment, this study conducted multi-point online electrochemical corrosion parameter measurements using a circulating flow experimental setup. The electrochemical corrosion behavior of P110 steel in flowing NaCl solution was analyzed, and the effects of different flow velocities and different concentrations of NaCl solution on the corrosion behavior of P110 steel were discussed. The experimental results show that in the flowing 2wt.% NaCl solution, the corrosion rate of P110 steel increases with the increase of flow velocity, and the corrosion reaction in the process is mainly controlled by the cathodic oxygen diffusion and anodic dissolution reaction together; in the high flow velocity NaCl solution, the shear force of the liquid on the wall and Cl− act together to destroy the corrosion product film, resulting in a continuous decrease of charge transfer resistance after the increase of Cl− concentration , the corrosion rate increases.
