Horizontal Or Vertical Baggers Form, Fill, And Seal At Speed

By John Henry, www.changeover.com

Form/Fill/Seal (FFS) is a bit of a vague term. I first heard it back in the 1980s when working with a system that molded a plastic bottle, filled it with liquid, and then sealed it closed. These days, I mostly hear it used to describe horizontal and vertical bagging machines, and that's how I'll use it here. Horizontal FFS machines are often called “flow wrappers.”

There are probably more similarities than differences between vertical and horizontal machines. However, there are differences.

Both vertical and horizontal machines use film supplied on a roll. This film can be any heat-sealable material, from monolayer plastics to co-extruded or laminated combinations of plastic, foil, board, and paper. In general, the film must have at least an inner, or adhesive, layer of plastic to allow heat sealing. If a lap seal is to be used, where the film is overlapped sealing inner to outer layer, it must include both an adhesive inner and outer layer. In a few cases, such as drinking straws in a paper sleeve, the paper layers may be mechanically joined with interlocking perforations rather than being heat-sealed.

Maintaining Roll Tension Is Key

In both vertical and horizontal machines, the film is unwound from a roll, passing over a set of dancer rollers that control tension. Some machines just pull the film from the roll, but generally a powered unwinder is recommended for more consistent tension control. Consistent tension is key to maintaining registration on the package graphics.

Please log in or register below to read the full article.