A practical selection guide for low target weights where feeder cut-off, product behaviour, weighing resolution and clean transfer into the real pack matter more than the number printed on a machine range.
Small-dose weigh filling can suit seeds, coffee, grains, granules, sweets, hardware pieces and some free-flowing powders, but the target weight alone does not determine the correct machine. A 25 g dose of large irregular pieces behaves very differently from 25 g of fine crystals or an aerated powder.
The useful comparison is between the smallest repeatable increment the feeder can deliver, the product already travelling when feed slows or stops, the load-cell signal stability and the ability to transfer the complete weighed dose without loss, bounce or residue. Pack-mouth width, static, dust and operator presentation can dominate the result at low weights.
Use product and pack evidence to choose the route before comparing individual machine configurations.
Often the first route to assess for free-flowing granules and regular pieces. Coarse and fine feed stages can approach the target progressively, but the feeder must be able to deliver a final increment that is small enough for the agreed tolerance.
Useful when irregular pieces, product fragility or higher accepted output justify several partial weights being combined. The product must distribute consistently across the heads and the pack or bagging machine must be ready for each discharge.
A specialist option for cohesive or fine powders that do not move predictably under vibration. Powder behaviour, screw geometry, agitation, dust control and container presentation require a representative trial.
Potentially more suitable where the commercial requirement is an exact piece count and individual component mass varies enough that weight cannot reliably represent quantity.
Test the factors that can change a stable laboratory result into an unstable production cycle.
Material continues to move after the control changes from bulk feed to fine feed or stops the feeder. The in-flight quantity must be stable enough for the controller to compensate without chasing individual fills.
The weighing assembly needs a stable zero and must be isolated from pack contact, cable strain, vibration and retained product. A high display resolution does not by itself prove useful process resolution.
A dose containing only a few large pieces can change in large steps. A fine but static-prone product may cling to the feeder or outlet. Both can produce variation for different reasons.
At low target weights, a small spill or retained amount can be a large percentage of the dose. The outlet, funnel, pack mouth and support height should be tested as one transfer path.
These are conditional first-party reference points, not universal promises. Final suitability depends on the representative product, pack and agreed acceptance method.
| Route | How to use the reference |
|---|---|
| LU-999 compact vibratory route | Reference weighing range 10–999 g; published output reference 6–15 bags/minute and approximately ±2 g under referenced conditions. Product volume, flow and pack handling still require a trial. Open the supporting page |
| LU-3000C semi-automatic route | Reference weighing range 20–3000 g with operator-presented packs and foot-pedal discharge. The sustained result includes opening, presenting and removing the pack. Open the supporting page |
| LU-GFKL420 automatic VFFS route | Ten-head reference configuration with a 10–2500 g weighing range. Published speed and accuracy references are conditional on product, film, bag length, sealing and the complete line cycle. Open the supporting page |
Set the trial around the real product batch, target weight, pack, outlet and operating rate. Record consecutive net weights rather than selecting the best fills. Note every adjustment, refill, spill, incomplete discharge and pack-handling interruption.
Review mean weight, sample standard deviation, minimum, maximum, range and any result outside the agreed band. Keep process capability, commercial giveaway and any applicable packaged-goods assessment as separate questions. A reference scale, tare method and acceptance rule should be agreed before the trial starts.
