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How Cans are Made

1. Cup Forming
The process starts with an aluminum coiled sheet which is fed through a press that punches out shallow cups.
2. Redrawing & Ironing
Cups are fed into an ironing press where successive rings redraw and iron the cup and reduce sidewall thickness to get a full length can. The bottom is domed to obtain strength required to withstand internal pressure.
3. Trimming
Cans are spun as a cutting tool trims the rough shell from the inside.
4. Cleaning
The cans are cleaned and pre-treated for decoration and inside coating.
  1. Pre-clean with water rinse
  2. Clean with commercial cleaner
  3. Cold water rinse
  4. Conditioning
  5. Cold water rinse
  6. Deionized water rinse
  7. Drying
5. Printing & Varnishing
Cans are rolled against a rubber cylinder to print up to four colors simultaneously, then moved to another station where a clear protective overvarnish is applied.
6. Bottom Varnishing
Cans are conveyed past an applicator that applies protective varnish to the bottom.
7. Baking
Cans wind through a conveyor in an oven to dry the printing.
8. Inside Spraying
A specially selected coating is sprayed on the inside of the cans.
9. Baking
Cans are conveyed through a tunnel oven that bakes and cures the inside coating.
10. Necking and Flanging
Cans are necked-in at the top to reduce can diameter and flanged to accept the end.
11. Light Tester
Clean cans are cycled through a light tester that detects pin holes and rejects defective cans...
12. Palletizing
After final inspection cans are palletized for shipments to the customer...
End-Making
1. Stamping
Ends are stamped out of pre-coated aluminum coil. Compound is added to assure a perfect seal between can and end at the customer’s plant.
2. Rivet Making, Scoring and Tabbing
Ends are fed through a high precision press where rivet making, scoring, and tabbing occur in consecutive operations.
3. Shipping
Ends are bagged and placed on skids for shipment to the customer.
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