Crown Packaging Technology, Inc.

Crown Cork & Seal Technologies Corporation

Stuart Alexander Monro

Keith Alan Vincent

Alain Presset

Jonathan Riley

Sylvia Maria Farrow

Terence Alexander Benge

Philip John Knight

A method for manufacture of a metal can body is described in which two or more stretching operations are used so as to reduce the thickness of the central part of a cup base, prior to drawing the cup sidewall and forming a can body. By using two or more stretching operations, it has been found possible to control the thickness of the base without significantly reducing pressure performance of the finished can. Alternative embodiments of apparatus comprising tooling for carrying out this method are also described.

Can manufacture

A method and apparatus are disclosed which are suitable for use in the manufacture of two-piece metal containers. In particular, a way of making cups from metal sheet is disclosed using a combination of stretching and drawing operations. The resulting cups have the advantage of having a base thickness that is thinner relative to the ingoing gauge of the metal sheet.

A method and apparatus are disclosed which are suitable for use in the manufacture of two-piece metal containers. In particular, the method and apparatus disclose a way of making cups from metal sheet using a combination of stretching and (re-)drawing operations. The resulting cups have the advantage of reducing the thickness of the base of the cup relative to the ingoing gauge of material.

A metal can body formed from a base stretching, drawing, and ironing process has a base having a hardness that is greater than the raw sheet, a thickness that is less than raw sheet, and a grain aspect ratio that is elongated relative to the raw sheet.

A method and apparatus for mechanically reshaping and/or forming textured features in the side wall of metal can bodies in which a can body is mounted on a profiled mandrel and rolled along a second mandrel or rail, which is also profiled. The tools are made from hard material but the second mandrel or rail is resiliently mounted. This mounting has been found to facilitate control of the depth of the profiled features formed in the can body. In particular, the problem of depth variability which will arise due to expansion of the machine and tooling in normal running conditions, or variability in thicknesses in the can body is avoided. Typically, the can body is clamped between complementary unformed regions on the tools during forming so as to prevent wrinkling or localised thinning of the can side wall.

Growing community of inventors

Oxfordshire, United Kingdom

Stuart Alexander Monro