| 摘要 |
PROBLEM TO BE SOLVED: To reduce a whole weight through the reduction of thickness of a connecting component and permit automation of connecting method without generating any abnormal thermal stress in a barrel by a method wherein the barrel is connected permanently to a frame by laser welding and excessive substances in the connecting area are removed. SOLUTION: Barrels 11 and a frame 12 are constituted of same substance, equal in chemical constituents and material structure, while the frame 12 is provided with through holes 121 for respective barrels 11 and the top surface 122 of the frame is machined so as to have a surface, abutted against the shoulders 112 of respective barrels 11. The ends 111 of barrels 11 are forced into respective through holes 121 in the frame 12 so that the shoulders 112 of the barrels 11 are abutted against the top surface 122 to connect the barrels to the frame previously. Thereafter, laser welding is effected in respective areas in abutting surfaces 112, 122 between the barrels 11 and the frame 12 as well as between rear end areas of the barrels 11 and the frame 12 to connect them. Further, excessive substances in the connecting areas are removed in the atmosphere of inert gas. |
