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Information × Registration Number 0219U003466, 0116U003609 , R & D reports Title Scientific basis development to identify and control the predefective condition of potentially dangerous long-term operation metal structures popup.stage_title Head Karpash Oleg Myhailovych, Registration Date 15-02-2019 Organization Ivano-Frankivsk National Technical University of Oil and Gas popup.description2 Object of study is damage of tubular steels as a result of prolonged use.As a result of the work, the analysis of existing methods and means of control of metal constructions has shown that the most common is acoustic control the disadvantage of which is the complexity of interpreting the results of control and the lack of information about the detected defect. The necessity of improving informative control and development of a new method of increasing the informative of ultrasound control for defining the type and size of defects, the use of modern means of control is substantiated.As a result of the performed graphical-analytical researches, a method for selecting the parameters of the piezoelectric converters ultrasound phase lattices has been developed, which allows to increase the informative of the ultrasound phase lattices control. An analytical dependence for focusing acoustic energy on the location of the expected defect was received to detect defects in the size of 1 mm. When grouping defects, the distance between them should be at least 2 mm to identify them as separate.A new method of processing the flaw detection information has been developed for defining the types and sizes of defects which consists in the processing of acoustic images, with the help of the software package Image J, which allows to reliably distinguish the most common types of defects in welded joints and determine their geometric dimensions with a relative error of up to 5%. The experimental research of industrial objects were conducted with the help of the developed method of defining the type of defects in metal constructions ("Neprovar ", " Nesplavlennia ", " Pora ") and determination of their sizes with an error of 0.5 mm, which is consistent with the results of theoretical research. The comparative tests of developed and standard methods of ultrasound flaw detection in industrial conditions on active metal constructions of prolonged exploitation, which is recommended to use for detecting and defining the type of defects of tubular elements with a diameter of dn ? 80 mm, storage vessels for gas and other metal constructions, thickness of not less than 10 mm. The methods of experimental determination of the characteristics of cyclic crack resistance of structural materials at the angle of opening of the top of the crack are described, and an appropriate experimental dependence is constructed. Based on conducted research the physical model of structural levels of material deformation and destruction of 17G1C steel at the micro, meso- and macro levels in the initial state and after exploitation work for various sections of the complete deformation diagram is proposed. Product Description popup.authors Біщак Роман Теодорович Галущак Мар'ян Олексійович Данилюк Ірина Михайлівна Доценко Євген Романович Жовтуля Любомир Ярославович Карпаш Андрій Михайлович Карпаш Олег Михайлович Коноваленко Ігор Володимирович Крижанівський Євстахій Іванович Луцак Дмитро Любомирович Марущак Павло Орестович Миндюк Валентин Дмитрович Попович Ольга Василівна Присяжнюк Павло Миколайович Чабан Назар Ігорович popup.nrat_date 2020-04-02 Close