PSI - Issue 20

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Mikhail M. Sidorov / Procedia Structural Integrity 20 (2019) 180–184 Mikhail M. Sidorov / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 3. Distribution of axial (a) and circumferential (b) stresses in the girth weld at the inner side: Z is distance from the weld axis, 2 is the pipe with a wall thickness of 10 mm; 1 is the pipe with a wall thickness of 8 mm 4. Conclusions Measurement of residual stresses showed that during arc welding of dissimilar thickness of pipes of low alloyed (0.9%C-2%Mn-1%Si) steel, the distribution of circumferential and axial stresses in the zone of the girth weld has different field levels. The results research was discovered that: Compressive residual welding stresses were found in the dissimilar thickness girth weld at the outer side but tensile stresses were on the inside. The values of tensile residual stresses were higher by 40-50 % in the thinner wall pipe than in the thicker wall one. Investigation of the distribution of residual stresses in in welded joints can be useful for developing methods to reduce the high residual stresses that occur after welding and also at deciding of constructive and technological task in the process of welding works. 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 Golikov, N.I., Sidorov, M.M., 2014. Investigation of the redistribution of residual stresses in cyclic loading of welded joints. Welding International 28(12), 970-972. Golikov, N.I., Ammosov, A.P., 2012. Prochnost' svarnyh soedinenij rezervuarov i truboprovodov, jekspluatirujushhihsja v uslovijah Severa (Strength of welded joints of tanks and pipelines operating in the conditions of the North). North-Eastern Federal University press, Yakutsk, pp. 323. Hensel, J., Nitschke-Pagela, T., Tchoffo Ngoula, D., Beier, H-Th, Tchuindjang, D., Zerbstd, U., 2008. Welding residual stresses as needed for the prediction of fatigue crack propagation and fatigue strength. Engineering Fracture 198, 123-141. Leggatt, R.H., 2018. Residual stresses in welded structures. International Journal of Pressure Vessels and Piping 85(3), 144-151. Pereira de Moraes, C.A., Chludzinski, M., Nunes, R.M., Lemos, G.V.B., Reguly, A., 2019. Residual stress evaluation in API 5L X65 girth welded pipes joined by friction welding and gas tungsten arc welding. Journal of Materials Research and Technology, 8(1), 988-995.