Two-piece can making process: Wall ironing and end forming
The cup is conveyed to the wall-ironing machine from the top. The ram first pushes it through the redraw ring to reduce its diameter to the punch diameter whilst retaining the sheet thickness. The cup is held by a blank holder to prevent puckers.
There is a gap between the punch and the wall-ironing rings 1 to 4 immediately after the redraw ring where the wall thickness of the can is reduced by "ironing" the tin plate and consequently lengthening the can.
At the end of this stroke, the punch with the can comes into contact with the base panelling tool and the can base is formed. When the ram is withdrawn, the can is removed from the punch by a stripper and conveyed out of the machine via an unloader belt.
