| 摘要 |
<p>A die forging method characterized in that it provides a high productivity and forming accuracy, comprising the steps of forming, in a pre-forging process, a close-fit part (4), a flange part, and a stepped close-fit part (6) of a spout tip metal fitting (3) using an upper outer punch (20) and an upper die (19) and forming, in a later hole forming process, a recessed and protruded part (7) by driving an upper inner punch (21) in a forging material while a die pin (13) is moved backward in the state that a back pressure is applied to one end surface of the forging material, whereby, because a part of the forging material is filled up in a die cavity in the forging process, the form of a forging process forming part can be created accurately.</p> |
