Impact shredding
Impact grinding is a type of grinding of solids . There are basically three different methods: material is thrown against a wall, material collides with a moving tool, or two material particles collide with each other. The material is exposed to high stress speeds (approx. 20 - 30 m / s).
When impacting against rapidly rotating tool surfaces and / or when spinning at high speed against the inner walls of the shredding machine, tool wear is generally high. That is why impact shredding is mostly used for soft to medium-hard, brittle materials. The crushing machines used are impact crushers , impact mills , hammer crushers and hammer mills .
In the case of autogenous shredding, on the other hand, material particles collide, which keeps wear very low, B. in the jet mill .
The fracture processes differ significantly from the pressure and impact comminution . The material is crushed very finely directly at the point of impact. From this point the fracture lines spread out like rays and form many medium-sized fragments and a larger residual cone. Heterogeneous materials such as ores are often crushed at the structural boundaries .
Individual evidence
- ↑ Walter Müller: Basic mechanical operations and their laws , Oldenbourg Verlag , 2008, ISBN 9783486598681 , pp. 186-187 [1]
- ↑ a b c d Walter Müller: Mechanical process engineering and its laws , Verlag Walter de Gruyter , 2014, ISBN 9783110343564 , pp. 191, 195 [2]
- ↑ Karl Höffl: crushing and classifying machines , Springer-Verlag , 2013, ISBN 9783642827105 , p 131, 152-153 [3]