Welding high-tensile steel under electro - conducting flux

摘要

Process for submerged arc welding of a high tensile steel inw hich the metal deposited in the neighbourhood of the weld is rapidly cooled with a liquid to produce a martensitic or lower bainite structure. Avoids brittleness associated with production of upper bainite when the weld is allowed to cool naturally and provides a good hardened joint. The cooling may be effected by discharging the liquid on the welded portion through ejection holes drilled in a lateral plate used in the welding process; the holes are in the rear end of the plate in the sliding direction. Welding is effected whilst preventing the vapour from the cooling liquid from flowing to the level of the molten weld metal; an inert gas shield may be formed between the latter and the ejection position of the cooling liquid. The finished joint is tempered.