The Paton Welding Journal, 2025, №01

2025 №01 (02)

DOI of Article 10.37434/tpwj2025.01.03

2025 №01 (04)

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The Paton Welding Journal, 2025, #1, 15-20 pages

Peculiarities of calculation of stress concentration factors in thin-sheet butt welded joints with the consideration of initial angular deformation

A.V. Moltasov, P.M. Tkach, M.M. Dyman, V.G. Kot, I.G. Tkach

E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: moltasov@gmail.com

Abstract
The paper is devoted to studying the influence of initial angular deformation caused by uneven transverse sagging of the butt weld during cooling on the stress concentration factors (SCF) in the transition zones from the face reinforcement and the weld root to the base metal (BM). An analysis of the existing formulas was carried out to determine the factor that considers the influence of initial angular deformation on the SCF on the fusion line of the weld with the BM. An analysis of the available formulas was carried out to determine the factor that takes into account the effect of initial angular deformation on the SCF on the fusion line of the weld with the BM. As a result, it was found that these formulas were developed for joints with a butt weld symmetrical relative to the median plane of the plates being welded and cannot be used for calculations near the weld root. A theoretical justification is given that initial angular deformation should lead to a decrease in stresses on the root side of the joint. New analytical formulas for the determination of the SCF on the fusion line of the weld root with the BM are proposed, considering initial angular deformation. A specific example was used to show that the presence of initial angular deformation really results in a decrease in stresses on the root side of the joint. The results of analytical calculations were confirmed by numerical calculations using the finite element method.
Keywords: butt welded joint, angular deformation, stress concentration, tension, bending, weld root

Received: 25.09.2024
Received in revised form: 22.10.2024
Accepted: 22.01.2025

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Suggested Citation

A.V. Moltasov, P.M. Tkach, M.M. Dyman, V.G. Kot, I.G. Tkach (2025) Peculiarities of calculation of stress concentration factors in thin-sheet butt welded joints with the consideration of initial angular deformation. The Paton Welding J., 01, 15-20.

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