| 摘要 |
PURPOSE:To smooth deformation of a stock and to reduce working load and pressurizing stroke at the time of pressing down the stock with a pair of side forming tools to obtain a rough shape billet by maintaining the spacing between the flat parts of said tools at the size smaller than the long side size of the stock. CONSTITUTION:A pair of vertical holding tools 6 disposed oppositely above and below restrains a stock slab 5 from a vertical direction. The short side faces of the stock 5 are pressed down by the side forming tools 1, 2 having slopes and flat parts. The tools 1, 2 and 6 are opened upon ending of such pressing down. The spacing (l) in the open state of the tools 1, 2 is adjusted to the size smaller than the width size L of the original slab. The feed of the stock 5 is, therefore, smaller than heretofore and is inch by inch. Namely, the tools are held spaced by as much as the stock 5 can be fed in by a prescribed feed pitch P. As a result, the progressive forging at the small feed rate is attained and, therefore, the periodic fluctuation in the thickness of flange parts is decreased and contribution is made to uniformization of the flange thickness. |
