The Paton Welding Journal, 2018, №05



2018 №05 (01)

DOI of Article 10.15407/tpwj2018.05.02

2018 №05 (03)

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The Paton Welding Journal, 2018, #5, 7-11 pages
 

Peculiarities of welded joints weakening in operating steam pipelines

V.V. Dmitrik¹, A.V. Glushko¹, T.A. Syrenko² and S.G. Grigorenko³

¹NTU «KhPI» 2 Kirpicheva Str., 61002, Kharkov, Ukraine. Е-mail: svarka126@ukr.net ²Kharkiv Machine Building College 79 Plekhanovskaya Str., 61068, Kharkiv, Ukraine ³E.O. Paton Electric Welding Institute of the NAS of Ukraine 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua
 
The development of recovery in metal of welded joints of heat-resistant pearlitic steel steam pipelines, which are operating for a long time in the creep conditions, is characterized by certain structural changes. Such changes cause the weakening in metal of welded joints. The article considers the peculiar features of structural and deformational changes, as well as the development of diffusion which occur in the process of recovery and leads to weakening in metal of welded joints of steam pipelines at their service of over 270 thou h. 10 Ref., 7 Figures.
Keywords: welded joints of steam pipelines, recovery, structural state, weakening, dislocations, diffusion, heat-affected zone
 
Received:                15.03.18
Published:               07.05.18
 
 
References

1. Dmitrik, V.V., Sobol, O.V., Pogrebnoj, M.A. et al. (2015) Peculiarities of degradation of metal in welded joints of steam pipelines. The Paton Welding J., 7, 10–15. https://doi.org/10.15407/tpwj2015.07.02
2. Dmitrik, V.V. (2000) Structure of welded joints from low-alloyed heat-resistant Cr–Mo–V pearlitic steels. Ibid., 4, 26–29.
3. Dmitrik, V.V., Syrenko, T.A. (2012) To the mechanism of diffusion of chromium and molybdenum in the metal of welded joints of steam pipelines. Ibid., 10, 20–24.
4. Rozenberg, V.M. (1973) Principles of high-temperature strength. Moscow, Metallurgiya [in Russian].
5. Dmitrik, V.V., Glushko, A.V., Syrenko, T.A. (2017) Structural changes in metal of welded joints after long-term service. The Paton Welding J., 7, 15–18. https://doi.org/10.15407/tpwj2017.07.03
6. Dmitrik, V.V., Glushko, A.V., Grigorenko, S.G. (2016) Features of pore formation in welded joints of steam lines in long-term operation. Ibid., 9, 51–54.
7. Khromchenko, F.A. (2003) Service life of welded joints of steam pipelines. Moscow, Mashinostroenie [in Russian].
8. Glushko, A. (2016) Research into defectiveness of welded joints of steam pipes operated over a long time. Eastern-Europ. of Enterprise Technologies, 6, 1(84), 14–20. https://doi.org/10.15587/1729-4061.2016.85852
9. Gottstein, G., Shvindlerman, L.S. (1999) Grain boundary migration in metals: Thermodynamics, kinetics, applications. New York, CRC Press.
10. Humphreys, F.J., Hatherly, M. (1995) Recrystallization and related annealing phenomena. Oxford, Pergamon Press.

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