- In contrast to the 1st chamber, the material is mainly ground by friction in the 2nd chamber,
- During the material transport through the 2nd chamber, the grain size is getting finer from coarse to fine,
- The ball charge composition is finer, i.e. balls with smaller diameters are chosen compared to the 1st chamber,
- To assure an efficient grinding, Christian Pfeiffer developed a classifying lining design which assures that the bigger ball sizes are kept at the beginning of the 2nd chamber and towards the end of the grinding length the sizes are getting linearly smaller.
