MACROSCALE LEVELS OF DIAGNOSIS OF THE MECHANICAL STATE OF THE METAL OF HIGH-TEMPERATURE PIPELINES

摘要

Technological pipelines, which represent a very complicated spatial system, have the highest metal content, significant number of structural elements, impressive length and multifaceted combination of design of the entire spectrum of high-temperature equipment. Currently, a fairly large list of companies of the Russian Federation, the importance of solving the problems of accurate diagnosis of the mechanical state of such shell structures of equipment operating in the thermo-power conditions, caused by the reduction in production volumes as necessary to compensate for out-of exploitation of its parts. Therefore, authors analyzed the strategy of a possible solution of this problem, consists in the assessment of condition of structural materials of bearing elements, given the initial technological heredity, and damages arising from operating on different structural and scale levels. It is shown that a comprehensive study of aging of the equipment and the materials from which it is made possible with determining the nature and parameters of macrodefects and determining the number and size of micro-defects in the bearing elements of the equipment. The relevance of the control of the stress-strained state of carrier elements on the basis of the calculated and experimental analyzes was confirmed. The necessity of the integrated (total) diagnostic of the object to determine its residual resource and evaluate its performance was substantiated. The fundamental importance of establishing a residual resource of higher scientific and methodical precision than the original and project was proved.Тhis paper shows that the degradation processes of the structural state of metal pipelines, caused by the influence of internal pressure and higher temperatures, inevitably lead to the changes in the mechanical state. A significant increase in the scatter of the mechanical properties of metal pipelines over its cross section, shown on the macro-scale level, for long term use testifies the exhaustion of stock service life as an indicator of mega-scale in general-level hierarchy of equipment condition.