Vol. 8 є 3, 2018 p 290-299

Pages

Article name, authors, abstract and keyword

290-299

T-pipe destruction origin investigation

Nikolay K. Tsenev a, Rinat N. Salikhov a, Oleg A. Kozyrev b, Dmitry A. Neganov b, Nikita Y. Nikitin a

a Science & Technology Centre of Pipeline Transportation of Transneft R&D, LLC (STC Transneft R&D, LLC), 144/3 Oktyabrya prospect, Ufa, 450055, Russian Federation
b Pipeline Transport Institute, LLC (Transneft R&D, LLC), 47a Sevastopolsky prospect, Moscow, 117186, Russian Federation

DOI: 10.28999/2541-9595-2018-8-3-290-299

Abstract: Based on the analysis of the causes and nature of connecting pieces of pipelines (“-pipe) destruction, Transneft developed and implemented new approach to conduct the failure studies. In order to investigate the causes of failure, work was carried out to determine the chemical composition of the metal of the part, the actual mechanical characteristics of the T-pipe metal, the parameters of the structural state, the nature and micromechanisms of the fracture surface. Taking into account the obtained results, computer simulation methods estimated the stress-strain state of a part in the operation process. The analysis revealed a deviation of the actual mechanical characteristics from the requirements of modern regulatory documentation. It is shown that in the branch area of the T-pipe, the level of residual stresses exceeds the values of the tensile strength, which, in combination with external influences directed along the vertical plane, can lead to the formation and subsequent development of cracks in the T-pipe.

Keywords: T-pipe, branch, main pipe, residual internal stresses, impact strength, crack, brittle fracture.

For citing:
Tsenev N. K., Salikhov R. N., Kozyrev O. A., Neganov D. A., Nikitin N. Y. T-pipe destruction origin investigation. Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation. 2018;8(3):290Ц299. DOI: 10.28999/2541-9595-2018-8-3-290-299.

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