Flow Wrap Packaging
Flow wrappers, or Horizontal Form / Fill / Seal or HFFS for short, is for when it makes sense to " push " a product vis-a-vis drop a product a la Vertical Form / Fill / Seal VFFS.
Film for flow wrap packaging is our strong suit. We have films for many products packaged on flow wrappers ( see applications ).
Images courtesy of Barrington Packaging Systems.
Flow wrappers are complex. They require constant care and feeding because they take a beating on a daily basis.
While there are a number of troubleshooting guides for horizontal flow wrappers, this one is in our opinion the best.
Flow wrappers require a stiff film ( high secant modulus ) , high slip ( low coefficient of friction ) , and film with differential melt temperatures. Either BOPP or lamination. A monololayer film will not work.
Flow wrapping and overwrapping are synonymous.
Seals are usually made with a heated roller to make the machine direction
( MD ) seal and bare metal jaws to make the end, or transverse direction ( TD ) seals.
For this reason, a " coex " BOPP prope, or film with thin layers of Low Density Polyethylene LDPE are a must- have to prevent film from sticking to the sealing surfaces.
Laminations of film with differential seal temperatures are easy to run on flow wrappers. This illustration is checks packaged in a lamination of polyester ( over 500 degrees melt temperature and LDPE sealing layer which has a melt point of around 300 degrees F.
Just like cars, there is range of new and used flow wrappers on the market ranging from entry level small flow wrappers to elaborate fully automated multi lane models.