Inverted curling method for metal beverage containers and beverage containers with inverted curls

摘要

Bottles (100) with inwardly curled upper portions at the bottle opening and methods and tooling for producing such bottles. The inwardly curled upper portions impart compressive stresses into the bottle material and can reduce a likelihood of material splitting because the upper portion may not be stretched to a larger outer diameter as with outwardly curled upper portions. The inwardly curled upper portions may be formed using rollers (500) with an entry radius (504) positioned near an outside diameter of the bottle opening. The inward curl is formed as the bottle material enters the rollers near an entry face (502) of the rollers, transitions through a work face (506) of the rollers, and exits the roller at an exit face (510) of the rollers. The resulting inward curl meets the edge of the bottle material near the inner surface of the bottle.