The working principle of a flour grinding mill is quite simple. It is composed of an inlet section, a grinding section and an output section. The inlet section has a simple gate that can be used to vary the amount of material fed into the machine. The gate can be totally closed when changing from one type of grain to another. This allows the operator to load a new type of grain into the inlet section without allowing it to mix with the grain that was previously loaded into the grinder.
The grinding section of the flour grinding mill is quite sophisticated and can be termed as the heart of the machine. It is responsible for grinding grains into flour. It consists of a shaft that rotates at extremely high speeds. The shaft contains hammers at its extremes. The hammers are swung through rotation of the shaft and in the process collide with the grains at high speed. The grains are therefore ground through the process of abrasion and collision. Once the large sized grains are broken down into small pieces, they are set into motion and in the process bump into each other to break further into fine grade flour.
The rotary hammers push the ground flour into a screening section where the grains are allowed to pass selectively. The screening section is the part that determines the grade of flour produced by a flour grinding mill. Some versions of grinders have pressure systems that push flour into the screening section. This ensures that flour doesn’t clog onto the screens to cause machine heating and malfunction. Various additives may also be included in the ingredients fed into the machine to prevent clumping of the flour. The additives also act as lubricants and can be used to reduce the heat coming from the grinding section. The graded flour is then pushed to the output section where it is collected in bags or sacks.