| 摘要 |
PROBLEM TO BE SOLVED: To increase freedom of design by enabling reduction of thickness of a valve seat by providing a method of joining the valve seat, wherein an excessive torque is not induced when the valve seat having a constricted part formed on its outer circumference is pressed and pressure-welded while being rotated. SOLUTION: The method of joining the valve seat is used for joining an annular valve seat 6 made of a hard metal having a constricted part 23 provided on its circumference to an opening of a head 5 made of a soft metal. In the method, solid phase fluid of the soft metal produced during pressure welding is filled in the constricted part 23, and the pressurization pressure 102b from the time of starting deceleration of the rotation speed of the valve seat 6 until a stop in a final stage of pressure welding is controlled at a pressure lower than the pressurization pressure 102a during pressure welding at an approximately steady rotation speed. COPYRIGHT: (C)2003,JPO
|
