A multihead weigher is the dosing system behind most high-speed snack, confectionery and dry-food form-fill-seal lines. Its advantage over a single weigh head is the principle of combination weighing: instead of trying to dispense the exact target weight in one shot, it weighs partial doses in many heads and lets a computer pick the combination whose total lands closest to target.
What combination weighing is
With a single head, you must stop the product flow at exactly the target weight, which is slow and prone to over- or under-fill. A multihead weigher instead fills each of its heads with a partial dose, then evaluates every possible combination of heads and discharges the one whose total weight is nearest the target — while the other heads refill for the next cycle.
How a multihead weigher works
The product enters through a dispersion cone, is distributed into radial feed channels, and each channel drops a partial dose into its own weigh hopper. The controller weighs every hopper, computes the best combination, and opens only the selected hoppers to release the dose into the bagger below. The empty hoppers refill while the next combination is already being computed.
Why combination beats single-head weighing
Combination weighing wins statistically: the number of possible combinations grows with the number of heads, so a 10- or 14-head machine can select a combination that is very close to target even though each individual dose is only approximate. That lets a line hold a tight weight tolerance at high speed — the reason Ishida and tna pair their multihead weighers (CCW and intelli-weigh) directly with VFFS bagmakers.
Accuracy vs speed
More heads mean more combinations and tighter accuracy, but the discharge rate is bounded by the weigh-and-combine cycle. On an integrated line the weigher and the bagger must keep pace — a Dession VFFS with multihead weigher runs 30–70 bags/min with the weighing accuracy the combination method provides.
Where it matters
Combination weighing matters most where the product is high-value and the net weight is a legal or commercial requirement — nuts, dried fruit, confectionery and weighed snack packs — and where giveaway (over-fill) must be minimized.
Last verified: August 25, 2026.
