VFFS bagging systems
A vertical form fill seal machine converts roll film into a bag, receives a controlled dose, closes the pack and cuts it for discharge or downstream handling.
Operating principle
A vertical form fill seal machine draws film from a reel, forms it around a tube, creates a longitudinal seal, closes the lower end, receives product from a dosing system, forms the upper seal and separates the finished bag. Each movement must remain synchronised with product delivery and film registration.
VFFS is a packaging format, not a universal dosing method. The machine may be integrated with an auger, weigher, cup, pump or another verified feeder according to the product. Product fall time, dust, bounce, strings and trapped pieces can influence the moment the jaws close and the length of clear film needed above the dose.
The bag former, film tension, pull belts and seal jaws must be matched to the reel and bag dimensions. A change in laminate, thickness, friction or print repeat can affect tracking and seal quality even when the nominal bag size remains unchanged.
Selection
The decision should connect the product, dosing equipment, bag geometry, film and downstream process. A nominal machine speed cannot be considered independently of those interfaces.
| Decision area | Why it matters | Evidence to request |
|---|---|---|
| Product and dose | Controls feeder type, drop timing, dust or splash risk and achievable bag length. | Representative material, dose range and replenishment conditions. |
| Film and bag style | Controls former geometry, sealing, pull, registration and reel arrangement. | Production film and approved finished-pack drawing or sample. |
| Seal requirement | Controls jaw style, temperature, pressure, dwell and cooling needs. | Agreed seal inspection and leak-test method appropriate to the pack. |
| Coding and inspection | Controls available print area, web timing, pack tracking and reject logic. | Real code data, position, verification rule and response to failure. |
| Discharge and line integration | Controls drop, conveyor orientation, checkweighing and case-packing interface. | Line layout, pack orientation and upstream/downstream control requirements. |
Operation
Format change may involve a new forming set, reel, recipe, dosing parts, code position and downstream settings. A controlled changeover should identify each part, record settings, clear previous product and film, then approve the first pack before routine production resumes.
Stop and restart behaviour matters because product can remain in the forming tube or dosing path while film and jaws stop. The control sequence should define whether a partial pack is discarded, how product is prevented from entering an open seal and how the line returns to a known tracking state.
Buyer questions
A VFFS machine can pack products that can be dosed reliably into a vertically formed bag, including certain powders, granules and other materials with a suitable feeder. Product fall, dust, bounce, temperature and seal contamination must be checked with the final bag and film before the application is confirmed.
VFFS output is determined by dosing time, product fall, bag length, film movement, seal dwell, coding, inspection and downstream transfer. The slowest repeatable stage and the need to recover from normal stops determine sustained line output, so an isolated nominal cycle figure is not enough.
A VFFS quotation needs the film construction, reel width, core and maximum diameter, print repeat, eye-mark position, unwind direction, seal requirements and finished bag dimensions. Production film is preferable for trials because tracking, friction and sealing can differ from an unprinted or nominally equivalent sample.
Pre-made pouches may be considered when the required pack features, material construction, reclose system or presentation are not practical to form inline from roll film. VFFS may suit efficient roll-film bag production. The decision should compare pack design, format range, product dosing, changeover and downstream handling.
