Flour Mill Machines: How to Specify a Milling Section for Wheat, Durum and Maize

Flour Mill Machines for Wheat, Durum and Maize Milling Lines

Almost every flour mill is built from the same short list of machine types, repeated across the flow and sized to the capacity of the plant. WUXI HASEN supplies those machines — as single units or as a complete milling section — for wheat, durum, maize and speciality grain lines from 60 to 3,000 tonnes per day. We are an export supplier based in Wuxi, China: we source the equipment, check it before it ships, and stay with the project until the line runs at the specification it was ordered to.

This page covers the machines inside the milling section itself — what sits between the cleaning house and the point where flour is collected. For the equipment that takes flour from the last plansifter to a bulk tanker or a packing line, see Flour Mill Parts. If your project starts further back, at the grain intake, Grain Machines covers the cleaning and handling equipment ahead of the mill.

What the machines in a milling section actually do

Grain arrives as a mixture of kernels, stones, dust and foreign seed, and leaves as flour, bran and by-products. The machines in between do three jobs, in sequence.

Preparation. The grain is cleaned, then conditioned: water and heat are added and the wheat rests in bins, so the bran toughens and the endosperm becomes easier to separate. Scourers lift surface dirt and loose bran off the kernel, and the dampening and resting stage does the rest.

Grinding and sifting. Roller mills open the grain and reduce it stage by stage. After each grinding passage a plansifter grades the stock by particle size and sends each fraction on to the passage that should handle it next. The balance between roller mill capacity and plansifter area is what decides whether a mill runs smoothly or bottlenecks.

Purification and finishing. Purifiers clean the semolina-size fractions, bran finishers and brushes recover the flour still attached to the bran, and the finished streams are collected for blending.

Machines we supply

Each machine below is listed with the models we supply and the duty it is normally bought for. Where a model is not shown, it is built to the capacity of the plant rather than sold from a fixed catalogue; the full technical data sheet for any model is available on request.

Roller mills

A roller mill is the main reduction machine in the mill. We supply roller mills with the roll length, roll diameter and flute specification chosen for the passage they will run in, so the grinding diagram can be balanced for a wheat, durum or maize flow rather than assembled around whatever rolls happen to be available.

Models and designs. The range includes MMRL, MMT with pneumatic control, MMT with electronic control, and MMDTL. Roller mills come in two designs — four-roll and eight-roll — with roll lengths up to 1,250 mm. The model is chosen for the process and the capacity it has to carry, and the four-roll design is the one normally specified where floor space is tight.

High plansifters

A high plansifter grades each grinding passage into fractions by particle size. It is supplied with the sieve stack and number of sections configured for the flow it serves, because a sifter that is short of area will hold back every passage downstream of it.

Models and designs. The FSFG plansifter is supplied in four-cabinet and eight-cabinet versions, with sieve grid specifications of 640 mm and 740 mm. Outer frames can be food-grade polyurethane or wood with melamine, and the parts in contact with the material are lined with food-grade stainless steel. The version and the sieve grid are chosen to suit the technology of the mill and its production capacity.

Purifiers

A purifier separates semolina-size stock from bran and fine material, which raises the extraction of low-ash flour without extra grinding. Purifiers matter most in lines producing bakery and noodle flours, where ash content is specified tightly.

Models. Two versions are supplied: the single cleaning machine and the compound cleaning machine. Which one is right depends on the flour technology, the capacity, and the installation space you have — the compound machine does more work in a shorter run of floor, the single machine is easier to fit into an existing layout.

Intensive wheat scourers

An intensive wheat scourer removes surface dirt, loose bran and insects from the grain before it reaches the first break. Fitting one reduces the load on the rest of the cleaning line and improves the colour of the finished flour.

Models. Two models, the 30/60 and the 45/80 friction scourer, covering capacities from 5 t/h to 20 t/h. The larger model is normally chosen where a single scourer has to keep up with a high-capacity first break.

Flow balancers

A flow balancer holds a steady, even feed to a downstream machine. It is most useful where two or more grinding passages feed a single sifter, or where the feed varies through the shift.

Models and duty. The gravimetric flow balancer is built to the capacity of the plant rather than picked from a fixed catalogue, and it measures the flow rate by weight, so the batching stays accurate whatever the moisture content and bulk density of the material. The units we supply include a touch-screen HMI, remote monitoring and online batching, and sit under the raw-material and product silos.

Bran brushes and bran finishers

A bran brush recovers flour that is still attached to the bran after reduction. Recovering it mechanically improves the extraction rate without sending more material through the rolls.

Models. Single and double bran machines are both supplied, and the beater rotor is fitted with different mesh sizes depending on the position it works in. That is what makes the machine pay: the mesh is matched to the stock it sees, so it recovers flour without breaking the bran into the flour stream.

Hammer mills

A hammer mill is used for fine grinding and for reducing by-products, including bran and maize. It is also the usual choice where a line needs a simple, robust mill for a secondary product stream.

Range and settings. The rotor runs at 1,500–3,600 rpm and screens normally range from 0.5 to 6 mm, which puts the finished particle size at roughly 0.5–1.0 mm for grain ethanol feed and 1–5 mm for cellulosic biomass, depending on how the material has been pretreated. A WFL vertical-shaft pulveriser is also available where the duty calls for finer grinding, down to 60–200 mesh, without a screen.

Rotary vibration sifters

A rotary vibration sifter is a compact screening machine used for check screening and powder grading, and on smaller-capacity lines.

Models and duty. A wide range of models covers 20 to 120 tonnes per hour, and the sifter can be run on its own or together with a vertical air suction separator and a self-circulating air separator, which take out light impurities and dust. It handles wheat, barley, rye, oats, corn, rice, soybean and sorghum.

Disinfectors and entolators

An entolator and disinfector is infestation-control equipment: it destroys insects and their eggs by impact, so that infested stock does not carry through into the finished product. Where it sits in the flow depends on what is being treated, and we will advise on that from your layout.

Duty. It destroys live insects and insect eggs in order to bring an infestation under control, which is what protects the shelf life of the finished flour. Because the machine is installed inside the flow, the treatment happens without holding up production.

What we need from you to specify a machine

Most of the information we need is already on your layout drawing or in your mill specification. The faster we get these six items, the faster we can put a proposal together:

• Target capacity, in tonnes per day or tonnes per hour

• Grain to be milled — wheat, durum, maize, or a mix — and its origin or hardness if known

• The flour specification you need to meet, including ash content if it is specified

• The passages or positions the machine will serve in your flow

• Power supply available: voltage, phase and frequency

• Destination port, and whether the machine ships as a single unit or as part of a larger consignment

If you are extending a mill that is already running, send the capacity and the layout of the existing line as well. Matching new equipment to machines that are already installed is routine for us, including where those machines came from another source.

FAQ: flour mill machines

Which machines does a complete wheat flour mill need?

A complete wheat flour mill normally needs roller mills, plansifters and purifiers, plus scourers and dampening equipment ahead of the mill and bran finishing machines behind it. The number of each depends on the capacity you are targeting and on the flour specification you have to meet.

Can you supply a single machine, or only a whole line?

Both. We supply single machines where a mill is being extended, rebuilt or de-bottlenecked, and complete milling sections for new plants.

Can you supply spare parts for these machines?

Yes. Spare parts are supplied alongside the machines on this page, and for mills that are already in production, including rolls, sieves and wear parts.

What capacity can you cover?

We cover complete milling lines from 60 to 3,000 tonnes per day, and individual machines for plants below that range.

Can you match machines to a mill that is already running?

Yes. Send the capacity, the layout and the power supply of the existing line, and we will match the new machine to the flow it has to fit into.

How do I get a quotation?

Send us the capacity you are targeting, the grain you will mill and the flour specification you need. We will come back with the machines we would propose for that line, and the information we still need from you.

Talk to us about your milling line

Tell us the capacity, the grain and the flour you need to produce, and we will come back with the machines we would propose and the questions we still need answered. If you are comparing options or rebuilding part of an existing mill, say so — the answer is often different from a new-build list. You can also see the equipment behind the mill in Flour Mill Parts, or contact us directly.