The work is devoted to corrosion-mechanical testing of steels used for field pipelines operating under the conditions of the combined action of a corrosive environment and abrasive wear. The article presents the results of comparative tests of steels 20A and 09G2S, which revealed the reaction of the tested steels to a change in the hydrogen index pH during wear. During the tests, an adapted methodology according to ASTM G65 was used, which allows one to evaluate the complex effect of corrosion and mechanical factors. 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. Based on the data obtained during the study, equations were derived that characterize the general tendency for the corrosion rate to change depending on the value of pH of the production medium. According to the research of surface topography and profilograms of the tested samples, the contribution of the contact area to the wear rate was estimated. According to the rate of corrosion-mechanical wear, the destruction rates of the pipe surface were determined by the means of action of the medium with different abrasive contents. Based on the analysis of the data obtained, equations are derived to determine the contribution of the corrosion-mechanical factor. Having analyzed the results of corrosion and corrosion-mechanical tests of selected steels, the possibility of predicting their service life by separately studying the contribution of various factors to the fracture process is revealed. It is especially worth noting that the data obtained play an important role in risk assessment in the design of oil field pipelines.
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