Hammer mills of the type HUV are are mainly used in the sectors of raw materials and the iron and steel industries for secondary and tertiary crushing of various materials. Often, they are employed for the fine crushing of medium-hard to soft materials like: Anhydrite, quicklime, lignite, coal, oil shale, dolomite, chalk, gypsum, glass, clay, limestone, etc.
The feed material which is conveyed to the processing chamber is crushed through impact as well as through attrition. Whilst on the inlet opening impact stress occurs, the crushed material is mainly comminuted through blows by the retracting effect of the rotor in the lower part of the narrowing crushing room. The material remains in the workspace until it is discharged through the grate gaps or opening section. The grinding path restricts the amount of oversize and supports the generation of a cubical and stress-free product
The HUV hammer mills are designed in such way that they can be driven at both continuous or variable rotor speeds. Inspection flaps and hinged housings are provided to facilitate easy maintenance. After opening of the hinged section access to all wear parts and grindings paths is provided.
The torsion-free mill casing is protected against wear through screwed-on lateral plates of wear-resistant material. Also, it is mounted on an anti-vibration base frame, which mostly reduces dynamic loads. The two sides of the mill housing can be opened/closed hydraulically.
A vital component of the HAZEMAG hammer mills is the disc-type rotor, in which are mounted the moving hammers. The heavy-duty rotor is of a steel disc design, with free moving (360°) hammers mounted between the discs and is shaft mounted and fitted with self-aligning roller bearings. The rotor can be operated in both directions. This way it is not necessary to turn the hammers manually and the utilization of the hammers is optimized. The flexible suspension of the hammers on the rotor ensures that the HUV hammer mill is sturdy enough against the intrusion of extremely hard foreign particles. The finely balanced design of the opposing hammers ensures balanced running. The hammers are made of compound castings and are easy to exchange.
For fine product an optional grate basket can be fitted. The grate (with grate bars) is built in the grate basket. This assembled unit gives the built-in grate bars the necessary mechanical stability and simultaneously fix the grate bar width which is required to generate a specific product size. The grate basket carrier with contains of a hydraulic cylinder for movement (in and out).
On the reversible version, the hammers can be utilized to their optimum by reversing the direction of drive without having to reverse the heads themselves. On the non-reversible HUV only one grinding path can be used. Instead of the grinding path, a bended plate is installed in order to protect the housing.
The HUV can be driven at either a constant or a variable speed.
All HAZEMAG HUV type hammer mills are equipped with a rotor turning devices, by means of which the rotors can be moved and locked in the appropriate position for safe and easier hammer replacement.
The rotor turning devices are of a worm gear with hydraulic drive and break.