PENETRATION WELDING METHOD OF T TYPE JOINT AND PENETRATION WELDING STRUCTURE

PROBLEM TO BE SOLVED: To obtain sufficient welding strength by eliminating a groove or a joint gap formed on the upper plate side and securely carrying out fusion welding up to the lower vertical plate side through 1 pass welding from the surface side of an upper plate. SOLUTION: In the penetration welding method of a T type joint, the fusion welding is carried out from an upper plate 1 surface overlapped on the upper surface of a vertical plate 3 thicker than the plate thickness T1 of the upper plate or upper surfaces of two parallel abutted upper plates 1, 2 up to a lower vertical plate 3. Arc welding in a non-consumable electrode method is performed using a shield gas supply means for allowing the shield gas 9b of an inert gas to flow, and fusion is carried out up to the lower vertical plate 3 while feeding a flux containing wire 4 filled with a flux agent for promoting penetration depth to an arc 6 welding part. A penetration width w of the vertical plate 3 after penetration of the rear surface of the upper plate is formed to be at least larger than the plate thickness T1 of the upper plates 1, 2 (w>T1), alternatively the welding cross-sectional area A of the penetration part of the rear surface of the upper plates 1, 2 or of a part with the penetration width w of the vertical plate 3 is formed to be larger than a cross-sectional area B1 in a plate thickness direction of the upper plates 1, 2 (A>B1). COPYRIGHT: (C)2009,JPO&INPIT