Malyk O. Evaluations of serviceability and durability of pipeline elements of subjected to static loadings and corrosive environments effect

An elastic deformed body with stress concentrators filled with environment and also structural elements with the welds that operate in a contact with working environment are the objects of researches; of development the calculation-analytical method for the evaluation of correlation of the field of mechanical stresses with local corrosive damages of materials near the environment-filled stress concentrators like cavities, shells, cracks and welds of pipelines elements; application of basic approaches of the theory of elasticity, thermodynamics of non-equilibrium processes and electrochemistry is the methodological basis of the work; dependences of current density and sizes of corrosion defect areas on the value of mechanical stress and conductivity of environments are established for the first time. The influence of residual stresses on displacement of electrode potential near a weld is evaluated. The analytical dependence of the depth of the crack-like defect filled with an environment on the concentration of stresses at its tip is found. The algorithm that enables the life time calculation of the pipeline with stress concentrators under action of working environment is developed; results are applied for estimation of residual life time of the pipeline systems of power TPP units at JSC "Zahidenergo"; heat-and-power engineering.