Can Making Process
Manufacturing Process of TULC
TULC (Toyo Ultimate Can) is a 2 piece can which constitutes drastic improvements in environmental friendliness through which were achieved by reviewing the fundamentals of materials properties and manufacturing processes. TFS, tin free steel, laminated with PET film on the interior and exterior surfaces, is processed into cups, similar how DWI cans are processed. Then, it is drawn, stretched and ironed to reduce the thickness of the can-body side walls (stretch-draw-ironing process). However, unlike DWI cans, no coolant (lubricant) is used during the can-body forming process, thus eliminating the need for coolant rinsing, and waste water treatment. Due to the internal layer of PET, inside lacquer coating is not required, hence significantly reducing CO2 emissions, a byproduct of the internal lacquer curing process.
Manufacturing Process of 2 Piece Cans (TULC)
| 1. Uncoiler | Uncoil coil for feeding to the Cupping Press. |
|---|---|
| 2. Cupping Press | Forms cup from coil. |
| 3. Redraw Press | Stretch, draws and irons cup to form can-body and can-bottom. |
| 4. Heat Setting Oven | Removes the distortion of PET film by heating. |
| 5. Trimmer | Trims upper portion to obtain the required height and check for pin holes. |
| 6. Printer | Prints a design on the exterior surface and applies varnish. |
| 7. Curing Oven | Aligns cans and cures ink. |
| 8. Necker Flanger | Narrows opening to form neck, and creates flange. |
| 9. Interior and Exterior Inspection Machine | Inspects for defects on the interior and exterior surfaces. |
| 10. Palletizer | Loads cans on pallets and wraps with shrink film. |
Ironing of DWI Cans
Material (in the form of a cup) is punched, using a punch sleeve, through a set of ironing rings. Pushing the cup through the narrow gap between the punch sleeve and the ironing dies form the cup, by ironing the cup walls into thinner and further extruded walls, into the can-body. Coolant is sprayed in order to lubricate and cool the tools and materials during this process, thus rinsing is required after molding.
Stretching and Ironing of TULC
"Stretch-draw-ironing", a molding method developed from the "tension and bending" process, is used to iron materials while applying a back tension. PET film laminate acts as lubricant to allow molding without the use of coolant, allowing for a decrease in material usage, and thus reducing environmental burdens.
