The Paton Welding Journal, 2016, №03



2016 №03 (04)

DOI of Article 10.15407/tpwj2016.03.05

2016 №03 (06)

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TPWJ, 2016, #3, 28-36 pages
 
Improvement of the technology of welding high-temperature diaphragms in steam turbine flow section

Journal                    The Paton Welding Journal
Publisher                 International Association «Welding»
ISSN                      0957-798X (print)
Issue                       № 3, 2016 (March)
Pages                      24-27
 
 
Authors
A.K. Tsaryuk¹, V.Yu. Skulsky¹, M.A. Nimko¹, A.N. Gubsky², A.V. Vavilov² And A.G. Kantor^2
1E.O. Paton Electric Welding Institute, NASU. 11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
²Company «Turboatom». 199 Moskovsky Ave., 61037, Kharkov, Ukraine. E-mail: office@turboatom.com.ua
 
Abstract
Special features and causes for operational damage in welded components of high-temperature diaphragms are considered. Comparative testing was performed of welding-technological properties of some commercially available coated electrode grades for welding heat-resistant steels of Cr–Mo and Cr–Mo–V compositions. Implant procedure and welding of Tekken technological samples were used to assess the delayed fracture susceptibility of 15Kh12VNMF + 15Kh1M1FL steel welded joints at application of selected electrodes. It is established that to ensure a high cold cracking resistance of these steel welded joints, it is necessary to apply preheating at 200–250 °C. Proceeding from the data of measurement of metal hardness in welds and HAZ of welded joints and weld metal impact toughness, an optimum mode of heat treatment of 15Kh12VNMF + 15Kh1M1FL steel welded joints was determined. It is shown that a softening zone of lower hardness forms in the HAZ metal structure of 15Kh12VNMF steel, in which the samples fail at testing for static tension at working temperature of 570 °C. 8 Ref., 4 Tables, 10 Figures.
 
Keywords: arc welding, heat-resistant steels, dissimilar steel welded joints, cold cracks, heat treatment
 
Received:                22.12.15
Published:               28.04.16
 
 
References
 

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2. OST 108.021.04–78: Stationary steam turbines. Welded diaphragms, guide apparatuses. General specifications. 01.01.79.
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