Operation of hammer mills
In the hammer mill, freely suspended hammers swing around at high speed. The resulting centrifugal force crushes the material against the special crushing plates in the interior of the grinding chamber. The product to be ground is fed to the hammer mill in doses, via a feed device with an integrated magnetic system and a heavy parts separator. This prevents contamination in the mill. In the mill, hammers attached to the rotor rotate at high speed and crush the product into pieces. The product that gets fine enough during the process leaves the grinding chamber through the sifter plate. Here, the particle size of the ground product is determined by the speed of the hammers and the mesh openings in the sifting plate. The following are particularly important for the grind fineness to be achieved:
- The hammers
- The sifter
- The properties of the raw materials to be ground
Depending on the properties of the product to be ground, single hammers, double hammers, or T-hammers are used. The effectiveness of the hammers is determined in particular by the following:
- The number of hammers
- The geometry of the hammers
- The distance between the hammers
- The distance between the hammers and the sifting plate
- The speed of the rotor and consequently the speed of the hammers
Hammer mills from Dinnissen are used particularly in the food, pet food, and feed industries, but they are also used in entirely different industries such as recycling and chemicals. This is because of the highly efficient grinding process, high reliability and safety, and very low noise level. Applications are generally soft to medium hard materials; the fineness of grind is normally in the range of 0.1 - 1 mm.