PSI - Issue 20

Nikolay I. Golikov / Procedia Structural Integrity 20 (2019) 161–166

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Nikolay I. Golikov / Structural Integrity Procedia 00 (2019) 000 – 000

the interior face of the pipe wall. From the superposition principle, RWS is added to the calculated stresses (173 MPa), so the total value is sufficient for the initiation of cracks on the inner wall of the pipe. The fatigue limit of welded joints of low- alloyed steels is defined as 0.4 ÷ 0.5 σ ts by Nikolaev (1978). Based on this, the allowable range of values for tensile RWS of field welds of the underwater gas pipeline is in the range of 53-110 MPa from the inner side of the pipe wall. 4. Conclusion Analysis of destruction of ring welded joints of the underground and underwater sections of the gas trunkline, 530 mm in diameter, in extreme cold climatic conditions, was carried out. Based on established research, it has been founded that in the inner surface layers of the mounting ring joints of thin-walled pipes, in the zone of the root seam, tensile residual stresses are formed. It was shown, that the initiation and growth of macrocracks in the field welds of thin-walled main gas pipelines occurs in the heat-affected zone on the interior face of the pipe wall in the zone of high tensile residual welding stress. Studies of the destruction of real welded joints of gas pipelines have proved that the residual welding stresses are the main factors influencing the development of brittle and fatigue cracks. This research allows to justify the need to develop technologies aimed at reducing the effect of residual welding stresses of annular welded joints of pipelines in order to increase their reliability. 5. Acknowledgments This work was supported by the Priority direction of the Basic Research Program of the State Academies of Sciences for 2013-2020 of Russia. Also the research was done using equipment of the Shared core facilities of the Federal Research Center of the Yakutsk Science Center of the Siberian Branch of the Russian Academy of Sciences. References Borodavkin, P.P., Beresin, V.L., Shadrin O.B., 1979. Podvodnye truboprovody [The underwater pipelines]. Publ. house Nedra, Moscow, pp. 415. Deng, D., Murakawa, H., 2006. Numerical simulation of temperature field and residual stress in multi-pass welds in stainless steel pipe and comparison with experimental measurements. Computational Materials Science 37, 269 – 277. Dong, P., Song, S., Pei, X., 2016. An IIW residual stress profile estimation scheme for girth welds in pressure vessel and piping components. Welding in the World 60, 283-298. Golikov, N.I., Terentyev N.N., Alekseeva M.N., Kynykitova M.A., Rodionov A.K., Argunova A.A., 2016. Analiz razrushenija svarnyh soedinenij podvodnogo perehoda magistral'nogo gazoprovoda [Analysis of the destruction of welded joints of the underwater crossing of the gas pipeline]. Svarka i diagnostika [Welding and diagnostics] 1, 60-64. Golikov, N.I., Sidorov, M.S., 2012. Redistribution of residual welding stresses in ultrasound impact treatment of welded joints in pipes. Welding International 10, 26, 765-768. Golikov, N.I., Dmitriev, V.V., 2012. Residual stresses in circumferential butt joints in the main gas pipeline at long-term service in the North. The Paton Welding Journal 12, 15-17. Gurova, T., Estefen, S.F., Leontiev, A., Barbosa, P.T., De Oliveira, F.A.L., 2017. Time-dependent redistribution behavior of residual stress after repair welding. Welding in the World 61, 507-515. Hemmesi, K., Farajian, M., Siegele, D., 2016. Numerical and experimental description of the welding residual stress field in tubular joints for fatigue assessment. Welding in the world 60, 741-748. Launert, B., Rhode, M., Kromm, A., Pasternak, H., Kannengiesser, T., 2017. Measurement and numerical modeling of residual stresses in welded HSLA component-like I-girders. Welding in the World 61, 223-229. Mirzaee-Sisan, A., Wu, G., 2019. Residual stress in pipeline girth welds - A review of recent data and modeling. International Journal of Pressure Vessels and Pipin 169, 142-152. Nikolaev, G.A., 1979. Svarka v mashinostroenii: spravochnik [Welding in mechanical engineering: a reference book]. Vol.4, Publ. house Mashinostroenie, Moscow, .pp. 512. Song, S., Dong, P., 2016. A framework for estimating residual stress profile in seam welded pipe and vessel components Part II: Outside of weld region. International Journal of Pressure Vessels and Piping 146, 65-73. Vasiliev, D.M., Trofimov V.V., 1988. Sovremennoe sostojanie rentgenovskogo sposoba izmerenija makronaprjazhenij [The current state of the X ray method for measuring macrostresses]. Zavodskaya laboratoriya [Industry Laboratory] 7, 20-29. Vinokurov, V.A., 1973. Otpusk svarnyh konstrukcij dlja snizhenija naprjazhenij [Tempering of welded structures for the stress reduction]. Publ. house Mashinostroenie, Moscow, pp. 213. Vinokurov, V.A., Grigoryants A.G., 1984. Teorija svarochnyh deformacij i naprjazhenij [Theory of welding deformations and stresses]. Publ. house Mashinostroenie, Moscow, pp. 284.