Seaming rollers, Ives-Way Sealer.
The 1st and the 2nd seaming roller have different specially countered grooves. During seaming only one roller makes contact with the can. When the lid is place on a can, the rollers are away. Then the 1st roller makes a pass, but the 2nd roller is waiting its turn. The 1st roller moves away and the 2nd roller flattens the seam.
1st Roller Operation
The curl of the lid is interlocked with the flange of the lid. The first operation should not be too loose or too tight, since there is no way to correct it later.
A curl of the lid a lid is wider than the can flange and the curl starts to turn around first.
The flange of the can follows as the roller moves towards the chuck.
The lid is interlocked with the can but the can is not hermetically sealed yet. The lid might turn around on top of the can if pressed hard enough.
The 2nd Roller Operation
Second roller begins to approach the hooks.
Second roller compresses interlocked hooks.
The interlocked layers of cover and can body flange are compressed, and the sealing compound is squeezed into open spaces to complete the hermetic seal.
Completed second operation.
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