Hammer mills of the type HUM and HNM are employed for the fine crushing and/or mill drying of medium-hard to soft materials. Examples: Anhydrite, quicklime, lignite, dolomite, electronic scrap, gypsum, glass, potash, limestone, china-clay, diatomite, chalk, phosphates, salts, French chalk and clay.
Due to their high level of flexibility, hammer mills can be adapted to different operating conditions. The housing is lined with replaceable abrasion wear plates. The hinged sections are opened hydraulically. The mounted equipment, such as e.g. impact and spacer strips (grinding path) and various grates can be replaced simply and employed flexibly, in order to achieve the targeted granular size. The rotors with shaft and bearings form the heart of a hammer mill. As a disc rotor, it is equipped with freely-swinging hammers.
By mill drying, the material is not only crushed, but dried simultaneously. Process gas is routed through the mill in direct flow with the crushing material. The dried goods generally leave the mill via grates and a downstream discharge worm-drive, with attached rotary gate values. The HAZEMAG rotary gate values serve for the exclusion of false air.
The fineness of the product is influenced by the control of the material flow.
- The double-rotor machine achieves its greatest throughput capacity in case of central material discharge, since the grinding grate or screen surfaces then have the largest area.
- If a grinding path is installed below the first rotor, the material reaches the area of the second rotor, and is thus ground in a two-stage process to a greater level of fineness.
- Optionally the product can be discharged pneumatically to top direction.
- The HUM mill is equipped with one rotor. As a result of the symmetrical structure of the mill housing, the rotor rotation direction can be reversed.