Numerical Identification of Corrosion Indicators when Assessing the Equipment Technical Condition

Abstract

The method is presented in the article concerning numerical identification of corrosion and corrosion resistance of metals, which serves to determine the degree of hazard of the corrosive state of technical devices of hazardous production facilities. Currently, the causes of metal failure are determined by metallography, radiography, ultrasonic, color, magnetic particle inspection or sample testing. Risk of the development of corrosion processes, depending on the type of corrosion, the characteristics of its shape, the depth of corrosion damage and the area of the affected surfaces, is determined visually or by the instrumental detection methods. Numerical identification of the indicators of corrosion and corrosion resistance of metals, proposed in the work, is carried out taking into account the location of the corrosion process, the form of corrosion damage, the size, unevenness and depth of penetration of various types of corrosion, the degree of damage to the surface by uniform and local corrosion (spots, ulcers, pitting). At the same time, according to the initial size of surface and deep corrosion, the actual size of the corrosion wear of a structural element is determined, and according to the scheme of a typical type and characteristic of the form of corrosion damage, the type of corrosion is determined. Further, taking into account the corrosion hazard score in accordance with the scale of corrosion resistance, a numerical indicator of corrosion and corrosion resistance of the structural metal is determined. Studies showed that the numerical identification of the indicators of corrosion and corrosion resistance of metals makes it possible to match the type of corrosion and the characteristics of the form of corrosion damage with the corrosion coefficient depending on the scheme of a typical type of corrosion damage. In addition, numerical identification shows the extent of damage to the surface by uniform and localized corrosion, including spots, pitting and other types of corrosion. Thus, it is applicable to determine the degree of corrosion hazard in assessing the technical condition and establishing the service life at any stage of the life cycle of equipment in hazardous industries.