The Mikro Pulverizer® Hammer and Screen Mill is a high-speed mechanical impact mill designed for continuous size reduction of a wide range of materials down to D90 < 45 μm. This device has evolved into the preeminent industrial mill with thousands of worldwide installations. The video here outlines key features of the hammer mill and demonstrates the new mechanical lifting mechanism.
The Mikro Pulverizer®consists of a high-speed rotor assembly fitted with hammers. The grinding chamber is fitted with a cover containing a multiple deflector liner and a retaining screen at the point of mill discharge. A screw mechanism is often used to introduce feed material into the grinding chamber. The grinding process is affected by three basic variables: the type of hammer, the rotor speed, and the size and shape of the screen opening.
There are two types of hammers: the “stirrup,” recommended where a fine particle size is desired, and the “bar,” which generates a coarser grind with a minimum of fines. Both types are tipped at the wearing edge with various abrasion-resistant alloys. Rotor speed affects the fineness of the grind with low speeds resulting in a coarse grind and high speeds producing a fine grind. Size and shape of the retaining screen openings also affect the product. In general, a finer screen opening will result in a finer grind. The retaining screen does not function as a sifting screen, except in coarse granulations.
Controlled Particle Size
Optimum particle size reduction can greatly affect chemical reaction speeds, solubility, weight, color, volume, appearance, and strength of ground products. Mikro-Pulverizers® provide accuracy in particle size control because the grinding action is entirely mechanical. Once a mill is set to deliver a certain product, it will continue to produce exactly the same result without adjustment.