Choosing the bag-making route too late can leave the equipment brief tied to the wrong material input. Start with the required finished package: VFFS forms the bag from rollstock, while premade-pouch equipment receives a bag that has already been converted.

Rollstock on a spindle
A plain film roll on a spindle. Rollstock is the incoming packaging material that a VFFS system must form into a bag.

Use VFFS as the first candidate when the required pack can be formed from a web on the proposed system. Start with premade-pouch handling when the specified converted pouch and its features are the fixed input. In either case, qualify the product dose, seal area and material sample together. This comparison uses public manufacturer descriptions, not our own machine tests.

Specify the finished pack first

The route must deliver the agreed geometry, opening and closure requirements. A pouch silhouette in a presentation is insufficient: obtain a sample or a controlled drawing with the actual material construction and required pack features.

Input or item Value or source Why it matters
Required pack Approved sample and drawing Defines geometry and consumer-use features
Material supply Roll specification or converted pouch specification Defines what the machine receives
Product and dose Representative product and target specification Defines the filling and contamination-control task
Seal acceptance Agreed product/pack checks Defines a successful finished pack
Format range Actual planned variants Identifies which changes need a demonstration

Viking Masek’s VFFS explanation describes a web passing over a forming shoulder and tube before filling and sealing. Its premade-pouch page states that the system fills and seals supplied pouches without rollstock. These are distinct material routes, not interchangeable names for the same input.

Open premade pouch
An open converted pouch beside a closed pouch. The supplied bag already has its structure before the filling operation.

Compare the work done on the packaging material

A VFFS proposal must address web handling and forming for the chosen pack. A premade-pouch proposal must address handling and presenting the supplied pouch for filling and closure. Both still need a suitable product delivery system and acceptable seals.

Roll-to-bag and ready-pouch-to-filled-pouch paths
Rollstock must become a bag on the forming route. The premade route begins with an already converted pouch that must be presented, filled and closed. Schematic, not to scale.
Decision factor VFFS route Premade-pouch route Evidence to obtain
Material arriving at the machine Continuous rollstock Individual converted pouches Supplier-controlled material specification
Pack formation On the proposed packaging system Before filling, at pouch conversion Finished-pack sample and forming/handling demonstration
Format change Web/pack geometry and applicable forming parts Supplied pouch size and applicable handling adjustments Old-to-new transition on actual samples
Product dosing Product-matched filler or scale Product-matched filler or scale Fill and seal-zone observations
Material defects to observe Tracking, forming, registration and seals Pouch presentation, opening and closure Reject log with retained samples
Commercial comparison Film, setup and accepted output Pouch supply, handling and accepted output Same order assumptions and cost boundary

Do not select a route solely because one supplier lists a higher nominal speed. Establish how that rate relates to your dose, material and pack geometry, and compare accepted output over an agreed window.

Use the format change to expose a weak fit

Choose representative extremes and difficult transitions from the intended range. Record what hardware is replaced, which settings change and what material is consumed before acceptance. A demonstration on one easy sample does not qualify all variants.

For VFFS, include the actual film construction in the trial. The film friction record helps describe contacting faces and observations when tracking or drag becomes an issue. A premade-pouch trial needs the actual converted pouch, including how it is delivered and stored for presentation to the machine.

For either route, include the product. A machine cycling without product can show part of the handling task; it cannot establish dose behaviour or the condition of the filled seal zone. Keep dry-cycle observations separate from production observations.

Make a conditional decision

Choose the route with a demonstrated path to the specified pack and a manageable transition to the next required format. If the pack is still open to redesign, evaluate that change explicitly rather than silently changing the acceptance requirement to fit a machine.

If the project has this condition Start here Resolve before committing
A fixed converted pouch with required features Premade-pouch trial Presentation, opening, fill and closure on that pouch
A pack geometry confirmed as formable from the selected web VFFS trial Forming, tracking, dosing and sealing together
Frequent geometry changes Compare transition records on both routes Parts, adjustment work and accepted restart output
Uncertain material construction Material qualification first Converter and machine supplier agreement on samples

A finished trial record should say which product, pack and material combination passed, what remained unresolved and what a change to any of those inputs would require. That is a stronger selection basis than a general winner between machine categories.

Methods and sources

The physical route descriptions come from Viking Masek’s published VFFS guide and premade-pouch page, read with local archived full text. The decision matrix and trial approach are editorial recommendations. We supply no universal rate, package-size range, cost advantage or material-sustainability conclusion. Sources were retrieved on 16 October 2026; the machinery subject guide links this selection task to related checks.

Source documents read: