PSI - Issue 30

ScienceDirect Available online at www.sciencedirect.com Sci nceD rect Structural Integrity Procedia 00 (2020) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2020) 000–000 Available online at www.sciencedirect.com

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 30 (2020) 149–153

© 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the EURASTRENCOLD - 2020 guest editors Abstract When applying technological methods of post-treatment of welded joints, it is necessary to control residual stress fields. The degree of redistribution of residual stresses mainly depends on the strength characteristics of steel, the geometric dimensions of the joint, the initial stress state, and treatment modes. The paper studies the redistribution of residual stresses in the ring joint of a pipe with a diameter of 530 mm made of steel (0.10%C-2%Mn-1%V-1%Nb-1%Al) of strength class K60. The pipes are connected by arc welding. Residual stresses were measured by the X-ray method based on measurement of microstrain of the crystal lattice of the material under its influence. Ultrasonic impact treatment (UIT) was done using a special technological complex. It consisted of an ultrasonic generator UZGT 0.5/27 and an ultrasonic impact tool BOMBUS. It is shown that after arc welding tensile residual stresses in the girth weld are formed in the inner side of the pipe. It was revealed that the UIT of the girth weld at a speed of 0.06 m/min from the inner side of the pipe wall contribute to the redistribution of residual welding stresses up to -100... 200 MPa, which provides the formation of compression stresses on the inner surface of the pipe. It’s shown that ultrasonic impact treatment reduces the level of tensile residual stresses and transforms them into compressive residual stresses. This can have a positive effect on the fatigue strength of the pipe girth weld. © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the EURASTRENCOLD - 2020 guest editors Keywords: ultrasonic impact treatment; residual stress; X-ray method; girth weld; pipe; arc welding. IX Eurasian Symposium on the problems of strength and resource in low climatic temperatures (EURASTRENCOLD-2020) Redistribution of residual stresses in girth weld of a pipe of strength class K60 after ultrasonic impact treatment Mikhail M. Sidorov a *, Nikolay I. Golikov a and Yuriy N. Saraev b Larionov Institute of Physical-Technical Problems of the North SB RAS of the Federal Research Center ‘Yakut Scientific Center SB RAS’, Oktyabrskaya St. 1, Yakutsk, 677980, Russia b Institute of Strength Physics and Materials Science of Siberi n Branch of the Russian Academy of Science, Akademichesky Ave., 2/4, Tomsk, 634055, Russia Abstract When applying technological methods of post-treatment of welded joints, it is necessary to control residual stress fields. The degree of redistribution of residual stresses mainly depends on th strength characteri tics of steel, the geometric dimensions of the joint, th nit al stress state, and treatment modes. The paper studies the redistribut on of re idual stresses in the r ng jo nt of a pipe with a diamete of 530 mm m de of steel (0.10%C-2%Mn-1%V-1%Nb-1%Al) f strength cla s K60. The pipes are connected by arc w lding. Residual stresses wer measured by the X-ray method based n measurement of microstrain of th rystal lattice of th material under its influenc . Ultrasonic impact treat nt (UIT) was done using a spec al tech ological omplex. It consisted of an ultrasonic generator UZGT 0.5/27 and n ultr sonic impact tool BOMBUS. It i shown that after arc welding tensile re idual stresses in the irth weld are formed in the i ner side of the ipe. It was revealed hat t e UIT of the girth at a speed of 0.06 m/min from the nner si e of the pipe wall co t ibut to redistribution of r sidu l w lding stresses up to -100... 200 MPa, which provides the fo mation of compression s esses n the inner surface of the pipe. It’s shown that ultrasonic impact treatment educ the level f tensile residual a d tra sforms th m into compres ive residu l stres es. This c n have a positive effect on the fatigue strength of the pip girth weld. © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the EURASTRE COLD - 2020 guest editors Keywords: ultrasonic im act treatment; residual stress; X-ray method; girth weld; pipe; arc welding. IX Eurasian Symposium on the problems of strength and resource in low climatic temperatures (EURASTRENCOLD-2020) Redistribution of residual stresses in girth weld of a pipe of strength class K60 after ultrasonic impact treatment Mikhail M. Sidorov a *, Nikolay I. Golikov a and Yuriy N. Saraev b Larionov Institute of Physical-Technical Problems of the North SB RAS of the Federal Research Center ‘Yakut Scientific Center SB RAS’, Oktyabrskaya St. 1, Yakutsk, 677980, Russia b Institute of Strength Physics and Materials Science of Siberian Branch of the Russian Academy of Science, Akademichesky Ave., 2/4, Tomsk, 634055, Russia

* Corresponding author. Tel.: +7-4112-35-84-29; fax: +7-4112-35-88-69. E-mail address: sidorovmm@bk.ru * Corresponding author. Tel.: +7-4112-35-84-29; fax: +7-4112-35-88-69. E-mail address: sid rovmm@bk.ru

2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open-access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under the responsibility of the EURASTRENCOLD - 2020 guest editors 2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open-access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review u der the responsibility of the EURASTRENCOLD - 2020 gu st editors

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the EURASTRENCOLD - 2020 guest editors 10.1016/j.prostr.2020.12.023