Technical Diagnostics and Non-Destructive Testing, 2026, №02

2026 №02 (02)

DOI of Article 10.37434/tdnk2026.02.03

2026 №02 (04)

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"Tekhnichna Diahnostyka ta Neruinivnyi Kontrol" (Technical Diagnostics and Non-Destructive Testing) #2, 2026, pp. 17-35

Analysis of the results of non-destructive testing of austenitic welded joints of the 3th power unit of the Chornobyl NPP

V.M. Torop, Ye.O. Davydov, M.D. Rabkina

E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. mail: v.torop@gmail.com

April 26, 2026 marked the 40th anniversary of the catastrophic explosion, which occurred in the 4th power unit of the Chornobyl NPP (ChNPP). Since then, a colossal amount of diverse work has been carried out to eliminate the consequences of the accident. To support the required level of safety and reliability of pipelines with a diameter of 325 mm (Dn 300) and wall thickness of 16 mm the Chornobyl Power Plant developed a special Program of diagnostic and repair-restoration operations. According to this Program, a considerable scope of radiographic (RT), ultrasonic (UT), penetrant (PT) and visual-measuring testing (VT) of welded joints of Dn 300 pipelines made from 08Х18Н10Т austenitic steel has been performed in the period from 1997 to 2005. Despite the fact that more than 20 years have passed since then, the NDT methods are based on the same physical principles, and practically the same methodological approaches to NDT are used. Therefore, analysis of the results of a large scope of operational control is very useful for understanding the reliability of NDT methods, used in modern daily practice. It should be noted that the work on analysis of the test results was performed as a separate task, and not specifically for evaluation and comparison of NDT methods, so that the analysis presented in the paper is objective, retrospective and unbiased, i.e. it reflects the possible and not the desirable result. Ref. 15, Table. 5, Fig. 17.
Keywords: NDT reliability, austenitic welded joints, radiographic (RT), ultrasonic (UT), penetrant (PT), visual-measuring (VT) testing, actual dimensions of the crack

Отрима?? 23.03.2026
Received in revised form: 08.04.2026
Accepted: 12.05.2026
Posted online: 30.06.2026

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Suggested Citation

V.M. Torop, Ye.O. Davydov, M.D. Rabkina (2026) Analysis of the results of non-destructive testing of austenitic welded joints of the 3th power unit of the Chornobyl NPP. Technical Diagnostics and Non-Destructive Testing, 02, 17-35. https://doi.org/10.37434/tdnk2026.02.03