How are Cans sealed?
What is a Can Seamer?
A can seamer is a machine used to seal the lid to the can body. The lid or “end” is usually tinplated steel while the body can be of metal (such as cans for beverages and soups), paperboard (whisky cans) or plastic.
The seam formed is generally leak-proof, but this depends on the product being canned. The seam is made by mechanically overlapping the two layers to form a hook.
Different parameters of the hook are measured and monitored to check the integrity of the seam under different conditions.
The shape of the double seam is determined by the shape of the seamer roll profile and the relative position. During the can seaming process, the seamer chuck holds the can while the rolls rotate around it. Initially, the first operation roll folds the lid (end) and then the second operation rolls tighten the resulting seam.
The first operation seam is critical to avoid problems like wrinkles (tightness issues) and leaks. The shape of the seam is determined by the shape of the first operation roll, the second operation roll, their relative positions and distances, lifter height, lifter pressure. Any damage or problems to the seamer or seamer tools can cause severe problems to the double seam like seam bumps, wrinkles, sharp seams, and open seams.