| 摘要 |
PURPOSE:To reduce the quantity of burr, to improve the yield of a product, and to prevent generation of a defective having undesfill, by executing roughing- down by use of an upper and lower non-symmetrical metallic die, when forging an H-section forging. CONSTITUTION:As for a roughing-down metallic die, a cavity die has an upper and lower non-symmetrical cavity die 3, a slit die line forms no straight line, a split die line of a flash-land 5 and a gutter 6 part, following both ends of the cavity die is positioned at the upper part than the split die line in the cavity die, and said metallic die consists of a punch 1 whose section is an inverted projecting shape, and a die 2 whose section is a recessed shape. A semi-product which is roughed down by use of this metallic die passes through each process of finish-forging, burr-removing and restrike-forging which are usually executed, and it is finished to an H-section forging. According to this method, the rough- forging material is saved, the quantity of generated burr is reduced, and the yield of a product is improved. |
