Case sealers for random size and uniform size cases
Depending on the application, a case sealer can be for a single uniform case size or it can be designed to handle random case sizes. Volume production of a single product only requires the same size carton at the end of the line. An order picker line, on the other hand, may require the closing of a variety of case sizes.
The uniform case sealer is simpler in design for folding the flaps and simultaneously moving the case forward. Horizontal moving belts grabbing both sides of the case and provide the forward motion through the tab folding/sealing cycle. The distance between the belts and the height of the top sealing arm are preset for the case size at the start of a production run. All critical parts of the sealer are ready to accept a case, therefore the sealing speed in cases per minute can be high. The cost of the sealer is low.
The random case sealer is more complex in design. When a carton enters the sealing station, side guide rails move in to center the carton and keep it moving straight. The top sealing tape dispenser, mounted on a post, moves downward to fold the flaps and apply the sealing tape. A flight bar moves the case forward through the sealing station. This makes it a more complicated mechanism and limits the packaging speed.