Production Steps for an Aluminum Can

Forming cups

• Refined aluminum is usually shipped in coils to the can plant, where it is uncoiled by a machine called an uncoiler. Once uncoiled, circular-shaped discs are cut from the sheets and pressed into a cup shape.

Ironing

• The cups are then fed into an ironing press, which lengthens and irons the cups into full-length cans. In this step, the bottom is also formed, and domed to be strong enough to endure the internal pressure the liquid contents will impose.

Trimming

• To ensure that all the cans are the same height, the tops of each cylinder are trimmed off according to predetermined specifications.

Washing

• The cans are then rinsed in water, washed with a commercial cleaner, rinsed again in cold water and conditioned in ionized water. This process is repeated twice.

Painting

• Clean cans are now drawn against a rubber cylinder, which may ink-print up to four colors. Once painted, the cans move to a machine that applies a clear protective coding.

Oven baking

• After washing and painting, the cans are moved into an oven to bake. The baking process ensures that paint and coating will not chip upon completion.

Internal Coating

• The inside of the can is coated with a spray that prevents the future contents of the can from reacting with the aluminum.

Necking and Flanging

• The neck of the can is now ready to narrowed, also called necking, where the lid of the can will be attached. Specifically, a lip called a flange is formed that helps to seal the lid once it is in place.

The final Inspection

• All finished cans are tested for leaks with a light capable of locating holes finer than human hair.