Short answer: count the roll length and sifting area in every offer and divide by the capacity. Two real mills give the range: 8.4 mm of roll per 100 kg of wheat a day in a compact 82 TPD mill, 11.7 mm in a 750 TPD commercial mill.
The total working length of all roll pairs in the mill. More roll length means gentler grinding at each passage, more flour from the same wheat and less bran in the flour. It is the first thing a cheap offer cuts.
The total screen area of all plansifters. Too little and fine bran passes into the flour: speckled flour, high ash, and a mill that chokes when you push capacity.
Only needed for low-ash bread flour and semolina. Purifiers clean the semolina before it is reduced. Some offers leave them out to look cheaper.
Engineers quote these per 100 kg of wheat milled in 24 hours. A 100 TPD mill is 1,000 units of 100 kg.
Enter your capacity. The result shows what the two reference mills would give at your size. Then enter the figures from any quotation you hold.
| Figure | 82 TPD mill | 750 TPD mill | What to read from it |
|---|---|---|---|
| Roll length | 6,900 mm · 8.4 mm per 100 kg | 87,500 mm · 11.67 mm per 100 kg | Large mills use more roll per tonne to reach higher extraction and whiter flour. |
| Sifting area | 51 m² · 0.062 m² per 100 kg | 470 m² · 0.063 m² per 100 kg | Almost the same ratio at both sizes. An offer far below 0.06 m² per 100 kg is short of sifters. |
| Purifier sieve width | 1 purifier, 49 cm × 2 | 8.0 m · 1.07 mm per 100 kg | Needed for bread flour and semolina. |
| Energy | 67–75 kWh per tonne of flour | 50–55 kWh per tonne of wheat | The same thing at 75% extraction. |
| Products | One flour grade and bran | Bread flour 70%, atta 6%, semolina up to 12%, coarse and fine bran | More flour grades need more passages and more roll length. |
The roller mill and plansifter models behind each figure are in the machine list of our quotation, line by line.
Each roller mill is listed with roll diameter and length, for example 250 × 1,000 mm. A double roller mill has two roll pairs, so it counts twice. Add them all up.
Up to a point. Extra roll length lets each passage grind more gently, which raises extraction and lowers ash. Past about 12 mm per 100 kg the gain is small and the cost and power go up.
Compare roll length, sifting area and purifiers first. A lower price with less roll length and sifting area is a smaller mill sold at the same capacity label.
No. A maize mill peels and degerms first, then grinds with fewer passages. Ask us for a maize configuration.
Related: How to compare flour mill quotations · Power consumption · Space requirements