Negoda E.

EVGENIY N. NEGODA, Ph.D., Professor, Department of Welding Production, School of Engineering, Far Eastern Federal University, Vladivostok. 8 Sukhanova St., Vladivostok, Russia, 690950, e-mail: negoda60@mail.ru

Fatigue of welded joints of large diameter pipes

Basing on the structural engineering model the article presents the algorithm of calculating the fatigue characteristics when making girth welding in large diameter tube. It offers a method of determining the asymmetry of the cycle and that of equivalent stresses, which enables one to calculate the parameters of fatigue in each physical point of the welded construction. Calculated are the characteristics of the stress-strain state of the welded tube within the real technological scheme as well as in the process of cyclic loading. The data have been obtained on the distribution of fatigue damage in welded joints.

Key words: welded pipes, the state of stress, fatigue parameters.

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