Can Making Process
Manufacturing Process of TULC
TULC (Toyo Ultimate Can) is a 2-piece can which enabled us to improve environmental-friendliness dramatically by reviewing the fundamental properties of materials and manufacturing process. TFS (tin free steel) laminated with PET film on the interior and exterior surface, is processed into cups, similarly as DWI cans. 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 and cooling agent) is used during the can-body forming process, thus eliminating the need for coolant rinsing, and waste water treatment. No inside lacquer coating is required because of the PET film laminate, significantly reducing CO2 emissions, by-products from 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.|
Comparison of forming methods between TULC and DWI
Ironing of DWI Cans
Can body is ironed and thinned by placing the material (in the form of a cup) between a punch sleeve and a set of ironing dies. Coolant is sprayed to lubricate and cool the tools and materials during this process, and thus coolant rinsing and waste water treatment are necessary.
Stretching and Ironing of TULC
"Stretch-ironing" is a basic molding method for TULC which was developed from the "tension and bending" process. “Stretch-draw-ironing”, is used to iron materials while applying a back tension. PET film laminate acts as lubricant to allow molding without using coolant and water. This enabled us to reduce can weight significantly as well as environmental burden without water use.