The Three Systems Side by Side
All three sit above a vertical bagger and drop one dose into each bag. They differ in what they measure: the multihead weigher measures weight, while the cup filler and auger filler measure volume.
| Multihead weigher | Volumetric cup filler | Auger filler | |
|---|---|---|---|
| How it doses | Combines weights from several heads to hit the target | Fills a set cup volume | Turns a screw a set amount |
| Suits | Granular, piece and frozen products: snacks, nuts, rice, IQF foods | Free-flowing granules with a steady bulk density | Powders: flour, milk powder, protein powder |
| Accuracy depends on | Piece size against target weight, product flow | How steady the bulk density stays | Powder flow, settling and aeration |
| Typical problems | Sticky or fragile product, small fills of large pieces | Weight drifts when density changes | Bridging, dripping, dust |
| Typical relative cost | Highest of the three | Lowest | Between the two |
Actual prices depend on the configuration.
The bag doesn't decide this. The dosing method is chosen separately from the bag format, so a pillow bag of rice and a pillow bag of flour can have completely different dosing above the same bagger. If you're still choosing the bag itself, see pillow vs side gusset vs quad-seal bags.
Multihead Weigher: Weighing Pieces
A multihead weigher splits the product across several weigh hoppers, then picks the combination of hoppers that comes closest to the target weight. Because it weighs instead of measuring volume, a change in bulk density doesn't throw it off the way it would a cup.
That makes it the usual choice for dry granular products, snacks and nuts. Frozen IQF products, large or fragile pieces and mixed products need configurations built for them. Powders are normally dosed by an auger filler instead.
Where it struggles:
- Large pieces in small bags. With few pieces per bag, one piece more or less moves the weight a lot. The heads and hopper size have to suit the piece size and the target weight.
- Fragile products. Chips and puffed snacks break when they drop too far or hit hard transfers, and a weigher adds drops of its own.
- Light, bulky products. Airy snacks fill a big hopper for a small weight, so the hopper volume follows from the bulk density.
- Sticky or coated products. Seasoning and oil coat buckets and hoppers and change how the product releases.
Size matters too. On our VP-YT compact baggers, the multihead weigher is built onto the bagger: the VP320-YT weighs 5–300 g with 10 or 12 heads, and the VP420-YT weighs 10–1,000 g with 14 heads. The VP320, VP420 and VP520 work with any of the four dosing systems; a multihead weigher for them sits on a platform above the bagger.
Volumetric Cup Filler: Simple, If Density Holds Still
A cup filler measures a fixed volume per bag. It's mechanically simple, and it's the lowest-cost of the three.
The catch is in the word volume. The filler delivers the same volume every cycle, so the weight in the bag is only as steady as the product's bulk density. A free-flowing product that packs the same way all day suits it well. A product whose density shifts between batches, or settles in the hopper, shows up as weight drift, and producers often set the fill a little over target to stay safely above the label weight. That extra product goes out free in every bag.
That's why our rice bagging lines weigh instead. Rice varieties differ in bulk density, so on our rice packaging lines the SVC260, VP and VGT take their dose from a multihead weigher.
Use a cup filler where dosing by volume fits the application: free-flowing, uniform granules where the weight tolerance allows for some variation. If the product is costly or the label weight is tight, compare the giveaway against the price difference before deciding.
Auger Filler: Built for Powder
An auger filler turns a screw inside a funnel, and each turn pushes out a set volume of powder. It's the standard route for flour, milk powder and protein powder. On our lines it runs with the VP Series for pillow and chain bags, and with the VGT for quad-seal bags of milk and protein powders.
Powder brings its own problems, and the auger has to be set up for them:
- Bridging. Cohesive powders bridge and rat-hole in the hopper, so the auger runs short and the weight drops. The agitator and hopper are chosen for how the powder flows.
- Density changes. Powder settles and aerates, so the same auger turn can deliver a different weight.
- Dripping. Free-flowing powder keeps trickling from the outlet between doses. An anti-leak outlet is matched to the powder.
- Dust in the seal. Fine powder rising from the bag reaches the seal area and causes weak or leaking seals.
How accurate is it? That depends on your powder and the auger set-up, so we confirm the weight result with your product in a test. More on this on the powder packaging page.
Four Questions That Decide It
- Is it a powder? Then start with an auger filler.
- Does the bulk density stay steady? If yes, and the product flows freely, a cup filler may be enough. If it varies, weigh it.
- How big are the pieces against the target weight? Large pieces in small fills need a weigher set up for them.
- What dose rate does the bagger need? The bagger can only run as fast as the weigher or filler delivers accurate doses, and each system has its own sustainable dose rate for your product. See what determines VFFS packaging speed.
Two other options exist for specific cases. A linear weigher is used for products suited to linear weighing. And for 1–5 kg spouted pouches of rice and other dry granular products, the Wide-Spout machines weigh with their own built-in weighing, so there's no separate doser to choose.
Questions to Ask Any Supplier
- Which dosing system do you recommend for my product, and why not the other two?
- Will you test it with my product at my target weight before I order?
- What weight result did the test show, and at what dose rate?
- How do you handle my product's specific problem: bridging, breakage, stickiness or density changes?
- Can the dosing unit and the bagger be tested together, so the line rate is confirmed as a whole?
FAQ
When is a cup filler enough?
When the product flows freely, its bulk density stays steady and your weight tolerance allows some variation. If the product is costly or the density changes between batches, weigh it instead.
Does the bag format decide the dosing system?
No. The dosing method is chosen separately from the bag format. The same bagger can take a multihead weigher, a cup filler or an auger filler, depending on the product.
Which dosing system gives the least giveaway?
It depends on the product. A weigher measures each dose by weight, so it isn't affected by density changes in the same way volumetric dosing is. But a multihead weigher costs more, so for a cheap, free-flowing product with a steady density, a cup filler can be the better buy. Test with your own product before deciding.
Find the Right Dosing System for Your Product
Send your product, target weight and bag. We run them on the machine free of charge, check the weight result and the dose rate, and send you the video and written record.
Request a Packaging Test