A vertical form-fill-seal machine forms a bag from a film roll, drops product in from above and seals it. A horizontal flow-wrapper feeds a solid product into a film tube and seals around it. The rule is simple: if the product flows, go vertical; if it holds its shape, go horizontal.
The product decides the axis
Powders, granules, liquids and pastes need gravity and a filling head above the bag — that is a vertical machine. Biscuits, bars, trays and assembled items keep their shape and can be conveyed into a film tube — that is flow-wrap. Trying to run a flowing product on a flow-wrapper, or a rigid tray on a VFFS, fails on the first shift.
VFFS vs flow-wrap
| Vertical (VFFS) | Horizontal (flow-wrap) | |
|---|---|---|
| Product state | Flows: powder, granule, liquid, paste | Solid, holds its shape |
| Bag creation | Formed from roll, filled from above | Film wrapped around product |
| Typical pack | Pillow, gusseted, doypack, M-fold | Pillow pack around a solid item |
| Dosing | Auger, cup, weigher or pump above | Product fed on a conveyor |
| Changeover | Forming tube by bag width | Film width and infeed setup |
Match the dosing system to the product, not the machine
On a vertical machine the dosing head is the part that decides accuracy. Free-flowing granules suit volumetric cups; fine powders need an auger; liquids need a pump; irregular product with variable density needs a weigher. The bagger is often the same machine — the dosing head is what changes.
Across the 13 vertical form-fill-seal series and 3 horizontal flow-wrap series we supply, the vertical range covers powder, granule, liquid, paste, tablet and weighing configurations on comparable bagging platforms.
Pack formats that need a specific machine
Doypacks with a zipper, M-fold gusseted bags and pyramid tea bags are not just settings — they need machines built for the format. If the pack shape is fixed by marketing, confirm the format is supported before comparing anything else.
See the vertical form-fill-seal range and the flow-wrap series in the full catalogue.
Figures in this article are drawn from the 137 machine series SilverSeal currently supplies, not from generic industry averages. Specifications vary by model — check the individual series page before specifying.
Frequently asked questions
Can one VFFS machine run both powder and granules?
Only by changing the dosing head. The bagger can stay the same; the auger and cup filler are different units.
Which format is faster?
Flow-wrap generally runs faster on solid items because there is no dosing step. For flowing product the comparison does not apply — only vertical will work.
What limits VFFS speed?
Usually the dosing head and the seal dwell, not the film transport. A faster bagger with the same filler gains little.
