| 摘要 |
PROBLEM TO BE SOLVED: To improve welding workability with a column member, and to enhance joining strength by forming a welding groove with the outer periphery of the column member on the inner peripheral edge of a ring-shaped joining member capable of being installed on the outer periphery of the column member, and arranging a flat part on this bottom surface. SOLUTION: Since a welding groove is formed in a straight line-shaped part on the inner peripheral edge of a joining member 12, a welding part 17 is executed only in a part for linearly opposing the outer periphery of a column member 11 and the inner periphery of the joining member 12 of a diaphragm 10. Opposed parts of an outer peripheral corner part of the column member 11 and an inner peripheral corner part of the joining member 12 are not welded to arrange a void. Since a flat part is arranged on a bottom surface of the welding groove, at welding, a welding arc sufficiently reaches up to the deep part so as not to cause a welding defect. Since a curved surface part is arranged on both end inner peripheral surfaces of the welding groove, welding metal sufficiently spreads to prevent the occurrence of a welding defect at the starting end and the trailing end of the welding part 17. |
