An auger filler upgrade replaces the drive and controls on an existing filler while keeping its frame, hopper, agitator and tooling. Many supplement packers operate imported volumetric auger fillers that are mechanically sound but held back by basic controls: an induction motor with a clutch and brake, or a stepper motor on a simple controller with no way to correct the dose during production.
The limits of a basic auger filler
A basic volumetric filler doses by running the auger for a set number of turns or a set time. On these machines, the symptoms are well known to filling room staff:
- Fill weights that vary from pack to pack, with a spread wide enough that the target has to be set well above declared weight
- Weights that drift through the run as the powder settles or the hopper level changes
- Manual adjustment of the auger setting after each check-weigh, which depends on the operator
- No recipe storage, so each changeover requires the settings to be found again
- Controller faults and spare parts that can only be sourced from the original overseas supplier
The machine itself is rarely the problem. The auger and tooling determine how consistently powder is delivered per revolution. The drive and controls determine how precisely those revolutions are delivered and whether they can be adjusted automatically.
Why the drive matters
On clutch-brake fillers, the auger stops when the brake engages, and the stopping point varies with brake wear and temperature. Stepper motors can lose steps under load, particularly with dense or sticky powders. In both cases, the number of auger revolutions per fill is not as consistent as the controller believes.
A servo motor is controlled in a closed position loop. It accelerates, runs and stops the auger at a precisely controlled position every fill, and reports its actual position back to the controller. The dose becomes a precise, adjustable number of revolutions, which is exactly what checkweigher feedback needs to correct for changes in powder density.
The auger filler upgrade scope
A typical retrofit includes:
- A servo motor and drive coupled to the existing auger shaft, with a mounting adaptor where required
- A new control panel with a programmable logic controller (PLC) and a touchscreen operator interface
- Recipe storage for each product and pack size, including target weight, auger speed and adjustment limits
- A communication link to the checkweigher, so every pack weight is used to trim the next fills
- Interlocks with the container conveyor and the existing guarding
How it works
- 1
Select the recipe
The operator selects the product and pack size, which loads the target, auger profile and adjustment limits.
- 2
Dose precisely
The servo turns the auger the set number of revolutions with a controlled acceleration and stop, every fill.
- 3
Weigh and correct
Each pack weight returns from the checkweigher. The controller trims the dose in small steps to hold the average on target.
- 4
Record
Weights, adjustments and recipe changes are logged for quality records and troubleshooting.
The control strategy that holds the average on target is described in more detail on our page on protein powder filling accuracy.
The commercial case for a retrofit
A retrofit delivers two benefits. A tighter spread of fill weights allows the target to be lowered, reducing overfill on every pack. And a supported, documented control system removes the risk of a filler stopping because a proprietary controller has failed.
Retrofit or replace?
- Keep the current controls. No outlay, but overfill continues and controller failures remain a risk.
- Buy a new servo filler. A sound option where the existing machine is worn out. Where the mechanics are sound, a new machine costs considerably more than a retrofit and still needs integration with the checkweigher.
- Net-weigh filling. Weighs every fill directly and is very accurate, but involves a larger investment and is often slower for fine powders.
- The original supplier’s upgrade. Worth asking about. Some imported fillers have no upgrade path or local support, which is often what leads packers to consider a retrofit.