Two quotes can both say automatic bottle filling machine and still be different machines. One meters a volume. The other stops when the bottle hits a weight. If you pick from a catalog photo, you find out at FAT that the oil foams, the juice starves the piston, or the water line never needed a load cell.
We spec this on liquid filling and bottle filling jobs the same way: product first, then valve, then the controller story.
Rotary fill heads and starwheel. The valve you see is not the metering story—volume vs weight is decided before this photo is taken.
Two paths, one bottle
| Volumetric | Gravimetric | |
|---|---|---|
| Measures | Volume (time, flowmeter pulses, piston stroke) | Weight (load cell) |
| Typical drinks | Thin juice, many CSD volume fills, piston / flowmeter SKUs | Edible oil, viscous / legal fill-by-weight SKUs |
| SKU change | Change time / pulse / cylinder; density assumed stable | Target grams; density swings hurt less |
| Where it fails | Foam, temperature swing, “same ml” ≠ same mass | Slower, more hardware, overkill on cheap still water |
Still water — gravity / level fill, not volumetric
A rotary water filling machine fills by gravity to a level: liquid rises until it reaches the return port, then the valve closes. That is not a piston stroke, not a flowmeter pulse count, and not a load cell. Buyers do not pay for gravimetric on 500 ml PET water unless a contract forces mass. If someone is selling load cells—or calling a gravity filler “volumetric”—on a 12,000 BPH water monoblock, ask what problem they think you have.
Oil and thick liquids — weight starts to earn its keep
Edible oil changes density with temperature. A piston that was “accurate” at 20 °C is short at 35 °C. That is why oil filling quotes often move to flowmeter volumetric with temperature compensation—or true gravimetric on small premium SKUs. Do not copy a water valve onto oil and call it a line.
Juice, tea, CSD — path beats the metering slogan
Pulp juice cares about bore and CIP more than whether the brochure says volumetric. Hot-fill cares about temperature. Carbonated drinks care about counter-pressure and CO₂. See juice and CSD when the drink is not still water.
How we write it on a Beyond quote
- Still PET water, one or two SKUs — gravity / level fill. Name the neck and BPH.
- Oil or syrup with legal fill-by-weight — say gravimetric or compensated flowmeter in the first reply, not after PO.
- Mixed hall (water + juice + can) — do not buy one “universal” metering story.
FAQ
What is the difference between volumetric and gravimetric filling?
Volumetric stops when a volume is reached (time, flowmeter, piston). Gravimetric stops when the bottle hits a target weight. Same automatic bottle filling machine brief, different stop condition.
Is a flowmeter volumetric or gravimetric?
Volumetric. Pulses equal a volume. Temperature compensation can approximate mass on oil; it is still not a load cell.
Does still water need gravimetric filling?
Almost never at beverage BPH. Gravity / level fill is the normal water filling machine spec—not volumetric, not gravimetric.
What should I send so you pick the right path?
Product (and temperature range), legal fill rule (ml vs grams), bottle drawing, and target BPH. “Automatic bottle filling machine, 6000 BPH” alone is not enough.
Water filling machines · Liquid filling · Bottle filling · Oil filling
