The Paton Welding Journal, 2012, №09



2012 №09 (05)

2012 №09 (07)

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The Paton Welding Journal, 2012, #9, 37-43 pages  

TECHNOLOGY OF REPAIR WELDING OF BOILER UNIT ASSEMBLIES WITHOUT POSTWELD HEAT TREATMENT

A.K. Tsaryuk¹, V.D. Ivanenko¹, V.Yu. Skulsky¹, S.I. Moravetsky¹, A.R. Gavrik¹, G.N. Strizhius¹, M.A. Nimko¹, S.I. Mazur², A.A. Trojnyak², Yu.V. Odin³

¹E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
²Tripolskaya HEPS, Ukrainka, Ukraine
³Kremenchugskaya HPP, Kremenchug, Ukraine
⁴OJSC «YuTEM», Bucha, Ukraine
 
 
Abstract
The paper considers repair welding of the damaged assemblies of boiler equipment at heat electric power stations and heat power plants made from heat-resistant steels of the Cr-Mo and Cr-Mo-V systems (collectors, heating surface pipes, T-joints, steam piping elements etc.), which exhausted their life under severe service conditions (at high temperature and pressure) that caused damages in metal mainly in the form of cracks. The technology recommended for repair of such damages involves manual arc welding using the 06Kh1M type electrodes combined with the 09Kh1MF type electrodes. It includes for the use of preliminary and concurrent heating with subsequent thermal recovery of a welded joint. Welded joints made by the suggested technology have high crack resistance and required mechanical properties. Present technology successfully passed the tests in repair welding of boiler equipment assemblies.
 
 
Keywords: repair welding, damages, heat-resistant steels, assemblies of boiler equipment, electrodes, preheating, thermal recovery, extension of life time
 
 
Received:                13.06.12
Published:               28.09.12
 
 
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