The Paton Welding Journal, 2013, №02



2013 №02 (11)

2013 №02 (02)

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The Paton Welding Journal, 2013, #2, 2-7 pages  

INVESTIGATION OF STRESS-STRAIN STATE OF WELDED STRUCTURES FROM AUSTENITIC STEEL AT RADIOACTIVE IRRADIATION

S.I. KUCHUK-YATSENKO¹, Yu.V. SHVETS¹, V.F. ZAGADARCHUK¹, V.I. SHVETS¹, V.I. KHOMENKO², S.I. ZHURAVLYOV² and A.Ya. SUDARKIN²

¹E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
²CJSC «Pskovelektrosvar», Pskov, Russia
 
 
Abstract
To determine the optimum mode of heat treatment of flash-butt welded joints of pipes from K56 steel the influence of soaking time and heat treatment temperature on impact toughness and yield limit was studied. Testing was performed in keeping with API 1104 and DNV-OS-F101 international standards. Metallographic examination of the influence of microstructure on strength properties of the joints in Neophot-32 light microscope and JAMP 2000F scanning electron microscope was conducted. Analysis of the obtained data allowed establishing the optimum heat treatment mode, at which the joints meet the normative requirements made of welds at construction of critical pipelines, including off-shore pipelines. 10 Ref., 11 Figures.
 
 
Keywords: flash-butt welding, pipe steels, pipelines, welded joints, mechanical properties, microstructure, impact toughness, heat treatment, forced cooling
 
 
Received:                29.11.12
Published:                28.02.13
 
 
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