How a two-piece drawn and wall-ironed food can is made

二片金属冲拔罐的制造

1. Aluminium or steel strip arrives at the can manufacturing plant in large coils.

2. The strip is lubricated with a thin film of liquid and then fed continuously through a cupping press, which blanks and draws thousands of shallow cups every minute.

3. Each cup is rammed through a series of tungsten carbide rings. This is the drawing and ironing process which redraws the cup to a smaller diameter and thins the walls, whilst increasing the height.

4. Trimmers remove the surplus irregular edge and cut each can to a precise specified height. The surplus material is recycled.

5. The trimmed can bodies are passed through highly efficient washers and then dried. This removes all traces of lubricant in preparation for coating internally and externally.

整理过的罐身经过高速清洗机并干燥。这一步骤是为了去掉润滑液残留为内外涂层做准备

6. The cans are coated externally by passing them under a waterfall of clear lacquer which protects the surface against corrosion.

7. Lacquered external surfaces are dried in an oven

8. The cans are passed through a flanger, where the tops of the cans are flanged outwards to accept the ends after the cans have been filled.

9. The cans are passed through a beader, where the walls of the cans have circumferential beads formed in them to give added strength.

 罐子通过卷边器在罐壁上加筋以加强罐体的强度

10. Every can is tested at each stage of manufacture. At the final stage they pass through a light tester which automatically rejects any cans with pinholes or fractures.

11. The inside of each can is sprayed with lacquer.
This special lacquer is to protect the can itself from corrosion and from any possibility of interaction between the contents and the metal.

每个罐子的内部都喷一种清漆。这种特殊的涂层是为了防锈以及防止内容物对金属材料的腐蚀

12. Lacquered internal surfaces are dried in an oven.

13. The finished can bodies are then transferred to the warehouse to be automatically palletised before despatch to the filling plant.