Can manufacture
View Patent ↗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.
1. A drawn and ironed metal can body formed of tinplate, the body comprising:
an ironed sidewall; and
an un-domed base integrally formed with the sidewall, the base including a peripheral countersink and a bottom wall radially within the countersink, grains in the base tinplate having an average aspect ratio of at least 1.4.
2. The can body of claim 1 wherein the average aspect ratio is between 1.5 and 2.5.
3. The can body of claim 1 wherein the average aspect ratio is between 1.6 and 2.2.
4. The can body of claim 1 wherein the average aspect ratio is approximately 1.8.
5. The can body of claim 1 wherein the average aspect ratio is at least 20% greater than average aspect ratio of raw sheet from which the can body is formed.
6. The can body of claim 1 wherein the average aspect ratio is between 20% and 100% greater than average aspect ratio of raw sheet from which the can body is formed.
7. The can body of claim 1 wherein the average aspect ratio is between 30% and 70% greater than average aspect ratio of raw sheet from which the can body is formed.
8. The can body of claim 1 wherein the average aspect ratio is between 40% and 60% greater than average aspect ratio of raw sheet from which the can body is formed.