Crushing in a medium/fast speed machine v.s in a slow speed machine
Hammer Mill (The FlexHammer™)
It is easy to change grates and thereby the endproduct fraction size.
When treating for example recycled wood the material is crushed in the breaknecks so that nails etc. are exposed and thereby easy to remove by magnet.
The end product is fluffy and suitable as fuel.
In occations where primary and secondary shredding/crushing is needed the FlexHammer™ is excellent.
When the material will be exposed to a drying process a fluffy material is preferred.
The FlexHammer™ performs a positive mixture, a homogenization of the in-fed materials which is valuable from a fuel perspective.
The hammermill produces a good fuel quality also with worn hammers which makes it easy to plan service.
The reject system prevents damages caused by uncrushable object being fed into the mill by mistake.
The knife bridge assists in the effective processing also of elastic materials.
Slow speed mill for smaller size
Shredding (now instead of the word crushing) takes place by the point of attach of the cutters or other, not necessarily where there is a breakneck. This makes it difficult to get good quality steel from the magnet separation.
The machine has a tendency to compress material which is a disadvantage in separation and drying as well as in combustion contexts.
Long material, elastic materials, video cassettes and plastic strips have great chance of passing the machine without crushing.
When uncrushable objects have been fed in by mistake the machine must be emptied, that is dug out from above (or through reject system on side).
Worn discs impair the endproduct quality (size).
It is a very costly procedure to change discs. Most commonly the axles are changed to new ones.
If the end product ends up being the wrong size there are very little one can do to change the fraction size.