To provide a working method by which two-dimensional projected length Lp of the outer corner parts of shapes such as a channel, an angle and a hat steel is made small and metallic worked goods having the small two-dimensional projected length Lp and a beautiful surface.
This method has a preforming stage where a preformed member having a prescribed cross-sectional shape which has at least a right-angle bent part is made by forming a long size metallic base stock by cold forming, a first rolling stage where a first formed member having a bulged part is formed by outside bulging outer side parts in the vicinity of the corner parts together with the corner parts of the preformed member cold or warm and a second rolling stage where a secondary formed member which has the outer corner part having a small radius Ro of curvature is formed by pushing the bulged part toward the inside of the corner cold or warm.
YAMASHITA TADASHI
OKA YOSHIYUKI
Satoshi Kono
Makoto Nakamura
Kurata Masatoshi
Takashi Mine
Yoshihiro Fukuhara
Sadao Muramatsu
Ryo Hashimoto
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