초록 ▼

An improved system and process of necking an upper end of a metallic container that will reduce the incidence of defects such as wrinkles and puckers during the necking process includes steps of performing a first stage operation to reduce a radius of said upper end by a first distance, and incremen

An improved system and process of necking an upper end of a metallic container that will reduce the incidence of defects such as wrinkles and puckers during the necking process includes steps of performing a first stage operation to reduce a radius of said upper end by a first distance, and incrementally further reducing the radius of the upper end by performing a plurality of subsequent reduction operations on the upper end. Advantageously, step (b) is performed so that the amount of radius reduction that is applied by earlier of the subsequent reduction operations is less than the amount of radius reduction that is applied by later of the subsequent reduction operations. As a result, increases of wall thickness that occur during the subsequent reduction operations will be utilized to permit greater radial reduction in the later steps, and will ease the amount of radial reduction in the earlier steps, reducing the potential for defects such as puckering and wrinkling.

대표청구항 ▼

[ What is claimed is:] [1.] A process of incrementally necking an upper end of a metallic container that has a first radius, comprising steps of:(a) die pressing the upper end of the metallic container so the upper end is reformed to a second radius, the second radius being less than the first radiu

[ What is claimed is:] [1.] A process of incrementally necking an upper end of a metallic container that has a first radius, comprising steps of:(a) die pressing the upper end of the metallic container so the upper end is reformed to a second radius, the second radius being less than the first radius by a first distance; and(b) after step (a), die pressing the upper end of the metallic container so the upper end is reformed to a third radius that is less than the second radius by a second distance, and wherein said second distance is greater than said first distance, whereby the process is performed in steps that increase in the amount of radial reduction that is applied, rather than in equal amounts of reduction as has heretofore been conventional.