The direct answer
Sachets are prepared for counting, cartoning and case packing by defining whether they leave as singles or strips, their orientation and spacing, how lane identity is handled, how rejects are removed and how accumulation behaves when the downstream machine stops.
The discharge is part of the production system, not an accessory chosen after the sachet machine. A pack that runs well through the sealer may curl, cling through static, overlap or turn during transfer. Test the real film, cut style and downstream demand signal before acceptance.
When should secondary packaging be specified?
Specify secondary packing at the same time as the sachet format and lane arrangement, before cutters, perforation and discharge conveyors are finalised.
The required case or carton count can determine whether packs are separated, perforated in strips or collated by lane. It also affects coder/inspection placement, reject tracking and accumulation. Leaving it late can require additional handling or lose lane identity after the packs are mixed.
How are individual sachets counted reliably?
Reliable counting requires controlled separation and spacing, a defined sensing point, stable orientation and logic that distinguishes an accepted sachet from a reject, gap or overlapping pair.
Transparent or reflective film, static, curled edges and connected perforations can affect detection. The line should define whether the count is verified independently and what happens when a sensor is blocked, a pack is rejected or the receiving carton is not ready.
When should sachets leave as strips rather than singles?
Strips can simplify manual handling, presentation or grouped counting when the consumer or secondary pack requires connected sachets, but they need controlled perforation and a downstream process designed for the strip length.
Singles are often easier to count individually and orient, but they can move unpredictably if very light or charged with static. State the required strip count, tear behaviour and whether the line must change between strips and singles.
What affects cartoner or case-packer infeed?
Infeed is affected by sachet dimensions, thickness, trapped air, seal stiffness, curl, surface friction, static, cut quality, orientation and the pattern delivered by the upstream lanes.
Accumulation and restart can change spacing even when stable running is acceptable. Define the receiving pocket or collation method and test the maximum expected stop. The controls should state when the sachet machine slows or stops and how packs already in transit are handled.
How are rejects kept out of counted batches?
Rejects are kept out by making the quality decision before the count is final, tracking each affected pack to a verified reject point and confirming that the reject actually occurred.
On a multi-lane line, the method must preserve lane and position identity until removal. A common chute can make this difficult. Define what happens if the reject bin is full, the reject device faults or the line stops between detection and removal.
Discharge and interface table
| Interface | Definition required | Acceptance challenge |
|---|---|---|
| Cut/perforation | Singles, strip count, tear strength and cut position | Normal and maximum intended output |
| Orientation | Face, leading edge, code visibility and permitted rotation | Start, stop, accumulation and restart |
| Counting | Sensor, batch size, verification and reset logic | Missing, overlapping and rejected sachets |
| Inspection/reject | Decision point, tracking, reject proof and bin status | Faulted reject device and full-bin condition |
| Downstream demand | Ready, stop, slow, fault and restart signals | Receiving machine not ready for declared duration |
Integrated test and enquiry inputs
- Finished sachet or strip samples using production-intent film.
- Required orientation, count, collation pattern, carton or case presentation.
- Lane count and whether lane identity must be retained.
- Inspection decision, reject method and reject-proof requirement.
- Maximum downstream stop, accumulation and restart condition.
- Line speed, controls ownership, safe interfaces and the agreed full-line acceptance test.
Safety context: where separate machines are assembled into a line, the safety of the interfaces must be assessed as part of the complete machinery assembly. Final guarding, controls and safe operating procedures require competent project-specific assessment. Read HSE guidance on machinery assemblies.