REDRAWING METHOD AND DRAWING/REDRAWING CAN

摘要

PURPOSE:To enable the forming by deep drawing, the thinning of a side wall part and the uniformization of a thickness by combining the radius of curvature of the corner part of a holding member and a redrawing die, the kinetic friction coefficient of the holding member and die and their redrawing ratio by selecting in the specified rang respectively. CONSTITUTION:The predrawn cup 1 formed from a covered metal sheet is held by the unnular holding member 2 inserted to this cup and the redrawing die 3 located thereunder. A redrawing punch 4 is provided co-axially with these holding member 2 and redrawing die 3 and so as to be movable inside the holding member 2, and the punch 4 and die 3 are relatively moved so as to mesh each other. In that case, the radius of curvature Rd of the action corner part 9 of the redrawing die 3 is taken in the size of 4.1-1.2 times the plate thickness of a metal sheet, and the radius RH of the curvature of the holding corner part 6 of the holding member 2 in the size of 4.1-1.2 times the plate thickness of the metal sheet. The plane like engaging part of the holding member 2 and the predrawn cup of the redrawing die 3 has the coefficient of kinetic friction of 0.001-0.2 and a redrawing ratio is taken in the range of 1.1-1.5.