Enter the net mixer volume (m^3), the density of mixed batch (kg/m^3), and the fill factor into the Batch Weight Calculator. The calculator will evaluate the Batch Weight.
Batch Weight Formula
Batch Weight = V * ρ * f
- V = net mixer volume (m³)
- ρ = material density (kg/m³)
- f = working fill fraction (decimal, e.g. 0.80 for 80%)
For sizing a mixer to a target weight, rearrange to V = W / (ρ × f). For a cylindrical tank, V = π × (D/2)² × H. For a rectangular tank, V = L × W × H. The calculator converts all inputs to SI units before applying these formulas, then converts the answer back to your chosen unit. Density is treated as the bulk density of the material as charged, so for powders use bulk density, not true particle density.
Reference Tables
Use these as starting values when the exact density of your material is not known.
| Material | Density (kg/m³) | Specific Gravity |
|---|---|---|
| Water / aqueous mix | 1000 | 1.00 |
| Milk | 1030 | 1.03 |
| Vegetable oil | 920 | 0.92 |
| Honey / syrup | 1400 | 1.40 |
| Flour, bulk | 590 | 0.59 |
| Granulated sugar, bulk | 850 | 0.85 |
| Dry sand, bulk | 1600 | 1.60 |
| Wet concrete | 2400 | 2.40 |
| Working Fill | When to use it |
|---|---|
| 40 to 50% | High-shear or high-foam liquids, gas dispersion, vigorous powder addition. |
| 60 to 75% | Standard liquid blending and most powder mixers. |
| 75 to 85% | Low-viscosity stable liquids with no foaming, gentle agitation. |
| Above 90% | Storage or holding only. Not recommended for active mixing. |
Worked Example
You have a 2 m³ jacketed mixer running an aqueous solution at SG 1.05, with a working fill of 80%.
- V = 2 m³
- ρ = 1.05 × 1000 = 1050 kg/m³
- f = 0.80
- Batch weight = 2 × 1050 × 0.80 = 1680 kg
To run a 1680 kg batch in a different mixer at 70% fill with the same product, the required net volume is 1680 / (1050 × 0.70) = 2.29 m³.
FAQ
Should I use bulk density or true density for powders? Use bulk density. The mixer holds loose powder, not compacted solid, so bulk density gives the correct charge weight.
What does "net mixer volume" mean? It is the usable internal volume of the vessel below the overflow point, excluding agitator displacement if the manufacturer has already deducted it.
Why is the answer different from the nameplate capacity? Nameplate capacity is usually the geometric volume. Real batch weight depends on your actual fill and the density of your specific formulation, not water at 100% fill.
Does the calculator account for agitator displacement? No. If the agitator displaces a meaningful volume, subtract it from the net mixer volume before entering the value.
