| 摘要 |
PROBLEM TO BE SOLVED: To provide the dimension decision method of a roll forming material capable of working a preliminary process by roll forming, and a manufacturing method for manufacturing the roll forming material to suspension parts through the preliminary process by roll forming. SOLUTION: An area of plural section taken just across the axis Fn, which is obtained from aluminum alloy suspension parts 7, is converted into an area of a circle, a maximum value of a virtual area Mn by adding an appropriate bur values is to be a sectional area of roll forming material 1 (step S215), and a truncated cone Tn is defined from two adjoining faces in a plural virtual circle Pn and a length of a virtual centerline C between the virtual circle. A volume of the aluminum alloy suspension parts 7 is displaced (step S213) by a rotating body which connects the truncated cone Tn, and the value of volume divided by the sectional area of the roll forming material 1 is to be a material length L for roll forming material. |
