Fill Weight Accuracy and Product Giveaway on Packing Lines
Every filling method has a spread of weights around its target, and to keep every pack at or above the declared weight you set the target slightly higher — that extra is giveaway. The tighter your filler's spread, the lower you can set the target. Multihead weighers, load-cell feedback on augers and check weighers are the three tools that tighten it.
Why can't a machine fill exactly the declared weight?
Products are not uniform: snacks vary piece to piece, powders change density, liquids foam. Each filler type has a typical spread — on our machines, auger fillers reach ≤±0.5% for 1–1000 g and our vacuum pouch machine ±3 g — so the target must sit above the declared weight by a margin.
How do I estimate giveaway?
Giveaway per pack = average actual weight − declared weight. Multiply by packs per year and the product cost per gram. Weighing 30 consecutive packs from your current process gives the average and spread you need.
Three ways to reduce giveaway
- Multihead weigher for irregular granules: combines hoppers to hit the target closely
- Load-cell feedback on auger fillers: corrects for powder density changes
- Check weigher after the packing machine: rejects light packs so you can safely lower the target
Frequently asked questions
Is a check weigher required by law?
Rules differ by country; many markets require packs to meet the declared quantity on average with limits on underweight packs. A check weigher is the practical way to prove it.