| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the pressure withstanding strength, the appearance and the corrosion resistance by drawing a body wall tapered part while applying the wrinkle-holding force, pressing a bottom panel dome part and the body wall tapered part so as to be engaged with each other while restricting both parts, and deforming a stepped part and a drawn part into a bottom radius part and a bottom panel wall part. SOLUTION: The minimum thickness from a bottom radius part 24 of a seamless can to a bottom panel wall part 25 is set to be tmin , and the thickness reduction ratio defined by the formula: thickness reduction ratio=(t0 -tmin )×100/t0 is set to be <=10%, where t0 is the original thickness of the seamless can. In addition, the redius rb of curvature of the bottom radius part 24 is set to rb <3t0 , and the rising angleαto the level on the center side of the bottom panel wall part 25 is set to beα>85 deg.. A stepped part and a drawn part can be formed without reducing the thickness through the drawing, or without generating wrinkles.</p> |
