The direct answer
Fragile or irregular granules should be assessed through the complete production path: transfer, feeder, hopper, weighing or volumetric dosing, release into the sachet and finished-pack discharge. The accepted result may need to control weight, piece mix, breakage, fines and seal cleanliness.
A gentle hand-fed dosing test can miss damage caused by normal transfer height or repeated vibration. Mixed pieces can also segregate even when total pack weight remains consistent. Define the commercial quality measure before choosing the dosing route.
How can a sachet line damage fragile pieces?
Damage can occur at transfer points, feeder gates, weighing buckets, narrow chutes, the product drop into the pack, sealing or downstream handling.
The risk depends on particle strength, shape, impact height, pinch points and the amount of product already in the sachet. Inspect the incoming product, intermediate points where accessible and opened finished packs. A weight check alone cannot show whether the product has fractured.
Why do mixed pieces segregate before dosing?
Mixed pieces can separate because of differences in size, density, shape and surface behaviour during transport, vibration, hopper residence and repeated refilling.
The dosing device may then receive a composition that differs from the original blend. If component ratio matters, define how it will be sampled and accepted. Test the normal batch-preparation and transfer method rather than mixing a small trial quantity immediately above the filler.
Which dosing routes should be compared?
Weighing, volumetric cups and other controlled piece-dosing approaches may be compared according to the commercial measure, particle variation, fragility, target dose and required output.
A weigher can control total mass while still allowing component mix to vary. A cup can be simple for a stable free-flowing product but is sensitive to bulk-density and packing changes. Use trials to compare the result that the customer will actually release, not only the convenience of the mechanism.
How should the drop path be included in a trial?
Use the intended feeder, chute, forming tube, sachet opening and discharge height so the product experiences the same impacts and constraints expected in production.
Record where fines or broken pieces first appear. The smallest pack or narrowest lane may be the most demanding because it gives less clearance and can increase collisions. Include a realistic hopper level and refill so the product flow pattern is representative.
What should be inspected in retained packs?
Inspect pack weight or count, component distribution, breakage, fines, seal contamination, pack appearance and any damage caused during discharge or secondary handling.
Label samples by time, lane, product batch and operating condition. Open a defined sample rather than keeping every pack sealed, and retain reference input product for comparison. Where appearance or piece ratio is subjective, agree a written or photographic acceptance method before the trial.
Granule decision table
| Product characteristic | Machine question | Trial evidence |
|---|---|---|
| Fragile or brittle | Where are the highest drops or pinch points? | Input/output breakage and fines comparison |
| Mixed size or density | Can transfer or vibration segregate the blend? | Component distribution over time and refill |
| Irregular pieces | Can the narrowest chute and pack opening pass them? | Blockage record and retained packs |
| Variable bulk density | Is mass or volume the controlled commercial measure? | Weighing/cup comparison under production feed |
| High lane count | How is product distributed and sampled by lane? | Lane-identified dose and quality results |
Information to provide
- Representative product showing the full particle-size and component range.
- Individual piece dimensions, fragility, fines limit and segregation concerns.
- Whether release is controlled by mass, count, component ratio or another measure.
- Intended transfer, feeder, hopper and refill method.
- Dose, pack dimensions, lane count, seal layout and required output.
- Inspection, reject, secondary packing and cleaning requirements.