Vertical Form/Fill/Seal VFFS

vertical form fill seal vffs packages

What is vertical form/fill/seal VFFS ?

Vertical form / fill / seal VFFS forms packages from flat rollstock by folding the film over a forming cone with an overlap, then sealing in the machine direction ( MD ) to create a tube. The tube is sealed in the transverse direction ( TD ), product is dropped in. Seal at the other end ( end seal ) starts the next cycle.

Click here for a directory of Vertical Form / Fill / Seal machine manufacturers.

Having seal troubles?   Download a Form / Fill / Seal troubleshooting guide.  

There are two types of sealing jaws:

Impulse Seal Jaws ( usually single layer film )
Used when barrier and pinhole-free packages are not critical. Plain or surface printed single (monolayer ) film is sealed inner layer to outer layer in the machine direction to create an "overlap" seal. The end seal is made with an "impulse" seal consisting of a heated wire covered with Teflon tape. Everyday examples include baby carrots, dry beans and cranberries.   Rice is a lanination of LDPE  / LDPE and runs on impulse jaws.

Resistance seal jaws ( laminated multilayer film or coex )
To make a "fin" seal, the inner surfaces of a 2 layer structure having different melting points are sealed together in a mirror image. The outer layer has a higher melting point than the inner "sealant" layer. The constant heat bare metal "resistance" end seal jaws penetrate the inner layer flow and caulk without distorting the outer layer which has higher heat resistance. A ubiquitous example is cereal box liner bag. 

In either style, performance of the sealant layer is critical. 

  Single Monolayer Films Laminations
Laminations Surface Print "buried" reverse print
Sealing Jaw Type Impulse Resistent
Back seam Overlap fin
Barrier properties Poor excellent
Seal quality Pinholes Integral complete seal
Channel leakers
Learn how fold over wrinkles can cause channel leakers in VFFS packaging.
Occasional preventable
Stand up pouches   Requires lamination
Cube / quad seal   Requires lamination

To calculate weight per 1,000 packages made with form/fill seal, see weights and measures.

Whether your requirements are single layer or lamination, we can provide the right sealant layer film for your application.