What does horizontal form fill seal mean in flow wrapping?
Horizontal form fill seal means that a product moves horizontally while a flat film web is formed into a tube, closed around the product and divided into individual packs. “Form” describes shaping the film, “fill” describes placing or carrying the product inside that film tube, and “seal” describes making the longitudinal and transverse seals.
Unlike vertical bagging, the product is normally a discrete item or controlled group presented along an infeed. The process is often called horizontal flow wrapping, flow packing or pillow packing.
How does flat film become a tube around the product?
The film is unwound, guided and drawn over or under a forming device that folds its edges around the product path. The former must match the pack width, product height, film behaviour and chosen seal position. Guides and tension control help keep the web centred while the product enters the newly formed tube.
A former is not a universal mould for every size. Large changes in product or pack geometry may require a different former or other format parts, which should be identified during the product trial.
Where are the fin seal and end seals made?
The longitudinal seal closes the film tube along the direction of travel, while the end-seal jaws close the tube across its width before and after each product. A fin seal usually brings the film edges together with their sealant surfaces facing; a lap seal overlaps one edge over the other where the film construction and machine arrangement permit it.
The finished pillow pack normally has one longitudinal seal and two end seals. Their position, appearance and performance depend on film construction, sealing window, product clearance and machine setup.
How do the jaws create the pack length and cut position?
The end-seal jaws meet in the gap between products, apply the required sealing action and cut between adjacent seals. The machine controls film travel and jaw timing so the cut occurs at the intended repeat. With registered film, a sensor also uses the printed mark to correct the print-to-cut position.
Product length alone is not the finished pack length. Allowance is needed for product variation, end-seal width, jaw clearance and the approved presentation. The pitch and pack-length guide explains those relationships.
Why must product, film and sealing-jaw movement stay synchronised?
Synchronisation keeps each product inside its intended film repeat and keeps the crimp jaws in clear film between products. If products arrive late, early or skewed, the jaws may meet the product, the pack may be too short or long, or the print and cut may drift from the approved position.
Sensors, infeed flights, metering belts and control logic can help, but the correct method depends on how products arrive. A stable wrapper cannot compensate for an uncontrolled infeed indefinitely.
Which parts of the complete packaging process may sit outside the wrapper?
The core wrapper may not include product singulation, orientation, automatic loading, coding, inspection, rejection, accumulation or end-of-line packing. Those functions can be separate machines or integrated modules, each with its own mechanical, electrical and control interface.
A quotation should state where the project begins and ends. Use the feeding guide and line-integration guide to define the wider process rather than assuming that “automatic flow wrapping” covers every step.