• Journal of Welding and Joining
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• 제32권4호
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• pp.1-9
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• 2014

A quantitative understanding on the effect of the welding conditions on weld joint dimensions and weld thermal cycle is difficult through experimental studies alone. The experimental realization of temperature distribution in the weld pool is proved to be extremely difficult due to the small size of welds, high peak temperature and steep temperature gradients in weld pool. This review deals with the heat transfer and fluid flow analysis to understand the parametric influence of a single wire submerged arc welding (SAW) and multi-wire SAW processes on the weld bead dimensions, temperature and fluid flow distribution in the weldment.

• Journal of Welding and Joining
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• 제29권6호
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• pp.71-76
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• 2011

Submerged arc welding method from both sides is generally applied to the welding of main panel manufacturing process during ship construction. The tandem SAW method is applied to improve the productivity. The various weld defects that occur during tandem SAW method are melt through, incomplete penetration, undercut and overlap etc. It could be thought that the reasons for these defects are mainly lack of prediction ability for penetration depth and deposited metal area. In this research, total 5 kinds of welding factors for experiment like current of lead pole, voltage of lead pole, current of trail pole, voltage of trail pole and welding speed are adopted. Weld tests are carried out for the analysis of variation effects of these factors on penetration depth and deposited metal area. Based on the test and analysis results, it is possible to obtain the prediction equation for the effect of these factors on the amount of deposited metal and penetration depth. As per the verification of the results by additional tests, it is confirmed that the prediction equation, include a error margin of ${\pm}2mm$ for penetration depth and ${\pm}10mm2$ for deposited metal area.

• Journal of Welding and Joining
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• 제4권3호
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• pp.43-49
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• 1986

Weldability of the TMCP steel manufactured by controlled rolling followed by accelerated cooling process was investigated. For comparison, two other steel plates produced by different manufacturing processes were selected; normalized and controlled rolled. Tandem submerged arc welding with both side one run technique was carried out. The results of this study can be summarized as follows; TMCP steel having the lowest carbon equivalent shows the best combination of mechanical properties, not only in the base metal but also in the heat affected zone. In the HAZ, the accelerated colling effect imarted on the trengthis releved by the weld thermal cycles, and thus the strength of the welded joint decrease substantially accompanied with the fracture in the HAZ. On the other hand, not only the softening but the fine microstructure can preserve the high toughness of TMCP steel in the HAZ.