The influence of aggressive environmental factors on the corrosion-mechanical wear and the risk of depressurization of oil field pipelines

The work is devoted to assessing the risk of depressurization of field pipelines operating under the conditions of the combined action of a corrosive environment and mechanical impurities. For a comparative assessment of the contribution of the corrosion factor to the fracture process, studies have been carried out on the development of corrosion processes on 20A and 09G2S steels in field media of different aggressiveness. The rate of destruction of the pipe metal under the influence of mechanical impurities was studied using the adapted ASTM G65 methodology, which makes it possible to evaluate the complex effect of corrosion and mechanical factors. Based on the data obtained during the study, equations were derived that characterize changes in the corrosion rate depending on the value of the hydrogen index (pH), degree of mineralization, CO2 content and temperature of the production medium and the content of solids. Using the obtained dependences, a methodology was developed for predicting the risk of depressurization of field pipelines depending on the composition of the transported medium and the dynamics of its change during field development. Application of the developed methodology will allow assessing the risks of depressurization under the influence of corrosionmechanical factors in the design of oil field pipelines.