| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel material gas joining method which can obtain a high joining quality, while preventing a complexity of operation, by relaxing a required polishing accuracy of the joining end faces. SOLUTION: After the end faces 1a, 3a of the steel materials 1, 3 are butt- welded at a given preliminary pressure, the welded portion is heated with a gas flame. When the preliminary compressed volume of the steel materials 1, 3 in their shaft directions reaches a given volume, the above preliminary pressure is released while keeping a relative positioning relationship of the steel materials 1, 3 fixed portions, and, when the butt welded portion reaches a given temperature, both steel materials 1, 3 are pressurized with a pressure equal to the preliminary pressure so as to carry out a compression until it reaches a given total compression volume. |
