| 摘要 |
A method of manufacturing a flange structure includes: forming a primary product by extending a columnar material in an axial direction by cold or warm forging such that each of the shaft portions is formed at each axial end of the material; forming a secondary product by making a middle portion of the primary product overhang outward by cold or warm forging such that a first overhang having a thickness greater than that of the flange is formed; forming a tertiary product by squeezing the first overhang by cold or warm forging such that a second overhang having an outline greater than that of the flange is formed; and defining an outer edge of the flange by cutting off an excessive portion of the second overhang. The second overhang without the excessive portion is the flange. |
