Our powerful hammer mills

Our hammer mills are used in animal feed production, wood, straw and grain grinding as well other industriell applications. They are characterized by a robust design of the grinding chamber. The robust inlet flaps and impact plates ensure wear resistance. High-quality components, especially the balanced rotor design, ensure a long service life and reduce maintenance costs.

Tietjen offers two series of hammer mills:

• large chamber hammer mills for high throughput rates
• high speed hammer mills with a smaller food print and grinding chamber areas from 0.3 to 1.9 m²

As a manufacturer Tietjen has machines in operation worldwide in various applications. The field of application is very wide. And the number of mainly natural raw materials and biomass that are ground increases continuously. Tietjen’s main focus in the grinding of raw materials is on:

• dry and free-flowing bulk materials, such as cereals
• high-fat and high-protein products, such as recipes for the animal feed industry or certain foodstuffs
• foodstuffs such as dried beans, pulses but also dried fruits
• fibers, such as wood and straw
• products for the industrial ethanol production

The machines grind a wide variety of input materials until the material reaches the desired particle size. Another important quality criterion besides the particle size is the uniformity or distribution of the particle size (both factors together determine the so-called grinding spectrum).

At the beginning of the process, the material to be ground is fed into the grinding chamber with a feeding or dosing device. The feeding process needs to be as uniform as possible – in terms of quantity per unit of time and per distribution over the width of the grinding chamber. The feeding device is as well used to ensure good ventilation of the hammer mill. This aspiration is necessary for transporting the material to be ground through the hammer mill, keeping the screens free, and cooling the grinding chamber. The aspiration is to be optimally controlled based on the specifications for vacuum and volume flow.

That is why the mill is called Hammer Mill!

In the grinding chamber of the hammer mill, the rotor rotates at high speed. A defined number of removable beaters are attached to the outer circumference of the rotor. These beaters are also called hammers. They are precisely balanced to avoid vibrations. In Tietjen hammer mills, these beaters can be replaced very quickly and easily.
During the process the rotating beaters grip the material to be ground as it enters the beating circle of the rotor. The impact of the beaters achieves the greatest particle size reduction effect. The beaters throw the pieces/particles at the impact plates and screens, where they are further broken by the impact. The ground material remains in the grinding chamber until it is so crushed that it can pass the screens in the grinding chamber.