Automatic Welding, 2016, №09



2016 №09 (10)

DOI of Article 10.15407/as2016.09.11

2016 №09 (12)

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Avtomaticheskaya Svarka (Automatic Welding), #9, 2016, pp. 56-60
 

Features of pore formation in welded joints of steam lines in long-term operation

V.V. Dmitrik¹, A.V. Glushko¹ and S.G. Grigorenko²

¹National Technical University «Kharkov Polytechnic Institute» 21 Frunze Str., 61002, Kharkov, Ukraine. E-mail: omsroot@kpi.kharkov.ua
²E.O. Paton Electric Welding Institute, NASU 11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
 
Abstract
The paper presents the results of investigation of pore formation in the metal of welded joints in steam lines operating for a long time under creep conditions. Features of pore formation in the regions of welded joint HAZ were revealed that allows improvement of diagnostic assessment of their residual life. Critical threshold of welded joint damage is local density of micropores of 0.8 μm and larger size on the level of 1500–1800 pores per mm². 7 Ref., 7 Figures.
 
Keywords: steam line welded joints, pores, residual life, diagnostics, damageability, diffusion movement
 
 
Received:                12.05.16
Published:               09.10.16
 
 
References

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