| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently suppress a reinforcement even when a tack welding is performed on the same side as the permanent welding side, and to obtain sufficient penetration bead even in the permanent welding. SOLUTION: A conical recessed hole 10 is formed by the counter sinking in advance on a face side of a butted part 6 of a cylindrical shell 2 to constitute a pressure vessel 1 to a semi-spherical shell 3 to be retrofitted thereto. The depth of this recessed hole 10 is set so as to be equal to or slightly larger than the penetration depth obtained in the regular tack welding subtracted from the thickness of shells 2 and 3, and the maximum diameter thereof is set so as to be smaller than the bead width by the permanent welding. When the tack welding is performed within the recessed hole 10, the penetration of a base material reaches the back side, and little reinforcement is generated on the face side. Therefore, when the permanent welding is performed on the butted part 6, the penetration reaches the back side even in a tack-welded part, and the so-called penetration bead is reliably formed. COPYRIGHT: (C)2003,JPO |
