The Paton Welding Journal, 2014, №11



2014 №11 (10)

DOI of Article 10.15407/tpwj2014.11.01

2014 №11 (02)

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The Paton Welding Journal, 2014, #11, 2-7 pages  

LIMINATION OF LOCAL DEFORMATIONS OF BUCKLING TYPE BY MEANS OF ELECTRODYNAMIC TREATMENT

L.M. LOBANOV, N.A. PASHCHIN, O.L. MIKHODUJ and T.G. SOLOMIJCHUK

E.O. Paton Electric Welding Institute, NASU. 11 Bozhenko Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
 
 
Abstract
Non-uniform heating of hull structures in welding of longitudinal-transverse framing promoted appearance of residual local deformations (buckling) in form of alternating bulges and indentations at adjacent sections of a panel. They have negative effect on service properties and appearance of the structure as well as hydrodynamic characteristics of ships, reducing their speed to 10 %. Traditional methods of buckling removal such as thermal and cold straightening have series of disadvantages (noise, vibration, significant consumption of energy carriers). Development of new methods of buckling straightening based on minimum energy consumption is a relevant task. Electrodynamic treatment is one such methods. Aim of present work is a study of effect of electrodynamic treatment on reduction of local deformations of buckling type in welded joints from aluminum alloys and low-carbon steels. Square samples of tee welded joints from AMg6 alloy and low-carbon steel St3 were used for simulation of buckling with different sign and deflection value. Mode of treatment corresponded to energy accumulated by storage, not exceeding 800 J. Effect of distribution of electrodynamic impacts, namely spot, circular and spiral ones, over sample surface on change of buckling form was investigated. Spot scheme has the lowest efficiency, and circular and spiral ones can be compared by efficiency. Comparative analysis showed that consumption of energy in electrodynamic treatment is significantly lower than in use of traditional methods of straightening. 10 Ref., 1 Table, 7 Figures.
 
 
Keywords: local deformations, buckling, low-carbon steel, aluminum alloy, electrodynamic treatment, treatment scheme, pulse energy, traditional straightening methods
 
 
Received:                20.06.14
Published:               28.11.14
 
 
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