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Information × Registration Number 0210U004056, 0107U005518 , R & D reports Title Development of theoretical basis for prediction of residual resource of welds of pipe-lines taking into account the presence of defects in pipes and influence of outer factors popup.stage_title Head Kushnir Roman Mykhailovych, Registration Date 05-02-2010 Organization Pidstryhach Institute for Applied Problems of Mechanics and Mathematics NASU popup.description2 Object of study - the processes of joint's material degradation of the oil-pipeline's pipes and fatigue failure after long exploitation. Objective of study - construction of a mathematical model to define the residual resource of the main oil-pipeline's joint and on this basis to optimize its exploitation parameters and also to develop the systematic approaches to estimate their metal degradation. Methods of study - mathematical modeling the process of a crack propagation under varying non-cyclic loading, the first thermodynamics law, criteria and methods of fracture mechanics to study the mechanical properties of different zones of joints of the main oil-pipeline's steel. Results and their novelty - a mathematical model to define the residual resource of the main oil-pipeline's joint under real exploitation conditions has been constructed. On this basis the estimation of the influence of such exploitation parameters as change of frequency of a gate valve closing and opening in a year change of the pressure amplitude in the pipe under oil flow turbulence change of the stress value in the pipe wall due to its squeering by soil on the pipe's residual durability has been made. The diagrams of corrosion-fatigue crack propagation in the joint material of oil-pipeline's pipe has been constructed, the study of shock viscosity of different zones of the joint steels in the initial and exploited (over 30 years) states has been made. In addition it has been shown that due to long exploitation of the pipes both with plant and butt joint the cyclic crack stability and shock viscosity of the metal of all their zones decrease. The shock viscosity of the basic metal and metal of the thermal influence zone decreases most of all due to exploitation. In the joint metal the exploitation degradation is more intensive. Branch of application: the main pipe-line transport, calculation of admissible regimes of its exploitation and determination of the state evaluation, estimation of its resource and exploitation safety. Significance of the study and conclusion: the procedure proposed on diagnosis of technical states and determination of the residual resource of technological equipment under long exploitation is sufficiently important to prognoze the failproot exploitation of pipe-line systems and other oil-gas equipment. The constructed mathematical model to define the residual resource of the joint of the main oil-pipeline under real exploitation conditions and development of the systematic approaches to estimate degradation of their metal by defining their shock viscosity should be noted. All this will enable to carry out the technical diagnostics of oil-gas equipment more accurately, especially it concerns the pipeline systems, and to predict their residual resource. Product Description popup.authors Андрейків Олександр Євгенович Долінська Ірина Ярославівна Махоркін Ігор Миколайович Никифорчин Григорій Миколайович Сас Наталія Богданівна popup.nrat_date 2020-04-02 Close