HORIZONTAL SUBMERGED ARC WELDING METHOD

摘要

PURPOSE:To obtain a weld metal having high toughness by disposing an upper steel plate and a lower steel plate in a specific groove state, setting specifically the bevel angle of the groove face of the lower steel plate and the groove face of the upper steel plate with a horizontal plane and performing horizontal submerged arc welding. CONSTITUTION:The bevel angle thetaL of the groove face 10a of a lower steel plate 10 with a horizontal line is set at >=15 deg. on the upgrade from a root part 11a toward the surface side of the steel plate and the bevel angle thetaU of the groove face 9a of an upper steel plate 9 with the horizontal line is set at thetaU-thetaupsilon+20 deg. on the upgrade from the part 11a toward the surface of the steel plate. The groove part formed in such a way is subjected to horizontal submerged arc welding by a baked flux contg. >=5% metallic carbonate in terms of content of CO2.