Rotor Mill

Home/Rotor Mill
  • The cyclone mill TWISTER is specially designed for the processing of foods and feeds for subsequent NIR analysis. The optimized form of rotor and grinding chamber generates an air jet which carries the ground sample through the integrated cyclone into the sample bottle. The air jet prevents the material from heating up, thus preserving the moisture content.

    The provided sieves guarantee an optimum particle size distribution so that it is not necessary to recalibrate the NIR spectrometer. The rotor speed can be adjusted in 3 steps allowing for perfect adaptation to the sample requirements. Cleaning the mill is quick and easy as the air jet effects a complete discharge of the material from the grinding chamber.

    This new cyclone mill in proven quality optimizes the reproducible sample preparation to NIR analysis thus allowing for meaningful and reliable analysis results.

    Application Examples

    Cereals, Corn, Feed Pellets, Forage, Pasta, Pharmaceutical Products, Soy, Rice, Tobacco, …

    Product Advantages

    • Ideal for grinding feeds, grains, forage and other similar products
    • 3 controlled speeds
    • Cyclone separator with 250 ml collecting bottle for quick extraction of sample
    • No cross contamination thanks to easy cleaning
    • Convenient operating panel
    • Robust industrial motor 900 W with long lifetime

    Function Principal

    In the cyclone mill TWISTER size reduction is effected by impact and friction between the rotor and the friction surface of the fixed grinding ring. The feed material passes through the hopper (with splash-back protection) onto the rotor which is rotating with high speed and is thus submitted to preliminary size reduction. The sample is then thrown outwards by centrifugal acceleration and is pulverized between rotor and grinding ring. The 2-step grinding ensures particularly gentle but fast processing. The feed material only  remains in the grinding chamber for a very short time. The integrated cyclone provides cooling of the sample and the grinding tools. This guarantees preservation of the sample properties to be determined. The ground material is separated in the cyclone and collected in a sample bottle.


    Applications: grinding prior to NIR analysis
    Field of application: agriculture, foods / feeds, medicine / pharmaceuticals
    Feed material: fibrous, soft
    Size reduction principle: impact, friction
    Material feed size* < 10 mm
    Final fineness*: < 250 µm
    Batch size / feed quantity*: < 250 ml
    Speed setting: 10,000 / 12,000 / 14,000 min-1
    Rotor peripheral speed: 52 / 62 / 72 m/s
    Rotor diameter: 98.5 mm
    Sieve sizes: 1 mm / 2 mm
    Drive: series-characteristic motor
    Drive power: 900 W
    Electrical supply data: different voltages
    Power connection: 1-phase
    W x H x D closed: 449 x 427 x 283 mm
    Net weight: 14 kg
    Standards: CE

    Quick View Details
  • Request Quote

    The Ultra Centrifugal Mill ZM 200 is a high speed rotor mill with unmatched performance. It is used for the rapid size reduction of soft to medium-hard and fibrous materials.

    Because of the efficient size reduction technique the ZM 200 ensures the gentle preparation of analytical samples in a very short time. The comprehensive range of accessories including a large variety of ring sieves and rotors as well as collection systems makes the Ultra Centrifugal Mill a versatile instrument that can be easily adapted to varying applications. The optional Vibratory Feeder is load-controlled via an interface and ensures a uniform grind at maximum output rate. When using a cyclone, the sample material is additionally cooled by the air stream and more rapidly discharged from the grinding chamber via the cassette pan with outlet. This effect can be increased by connecting a vacuum cleaner.

    With thousands of installations, the ZM 200 has become a standard for food and feeds, for the chemical industry as well as for agricultural testing.

    Application Examples

    Bones, Cereals, Chemical Products, Coal, Coffee Beans, Collagen, Corn, Dried Fruit and Vegetables, Dried larvae, Drugs, Electronic Components…

    Product Advantages

    • Powerdrive with optimally matched frequency converter and 3-phase motor
    • Gentle and very rapid size reduction by pre- and fine grinding in one run
    • Wide speed range
    • Patented cassette system for maximum sample recovery and easy cleaning
    • Easily exchangeable grinding and sieve inserts
    • Defined final fineness due to ring sieves with aperture sizes from 0.08 – 10 mm
    • Comfortable safety housing with automatic cover closure
    • Motor compartment and electronics protected against dust and material penetration
    • Comfortable parameter setting via display and ergonomic 1-button operation
    • Wide range of accessories including various collection and feeding systems, rotors and sieves

    Function Principle

    In the Ultra Centrifugal Mill ZM 200 size reduction takes place by impact and shearing effects between the rotor and the fixed ring sieve. The feed material passes through the hopper (with splash-back protection) onto the rotor. Centrifugal acceleration throws it outward with great energy and it is precrushed on impact with the wedge-shaped rotor teeth moving at a high speed. It is then finely ground between the rotor and the ring sieve. This 2-step grinding ensures particularly gentle but fast processing. The feed material only remains in the grinding chamber for a very short time, which means that the characteristic features of the sample to be determined are not altered. The ground sample is collected in the collecting cassette surrounding the grinding chamber or in the downstream cyclone or paper filter bag.

    Applications: fine grinding
    Field of application: agriculture, biology, chemistry / plastics, construction materials, engineering / electronics, environment / recycling, food, geology / metallurgy, medicine / pharmaceuticals
    Feed material: soft, medium-hard, brittle, fibrous
    Size reduction principle: impact, shearing
    Material feed size* < 10 mm
    Final fineness*: < 40 µm
    Batch size / feed quantity*: 300 ml with standard cassette // 20 ml with mini-cassette // 1000 ml with paper filter bag // 4500 ml / 2500 ml / 450 ml / 230 ml with cyclone
    Speed at 50 Hz (60 Hz): 6,000 – 18,000 min-1, free selectable
    Rotor peripheral speed: 31 – 93 m/s
    Rotor diameter: 99 mm
    Types of rotors: 6-tooth rotor / 12-tooth rotor / 24-tooth rotor / 8-tooth mini-rotor
    Material of grinding tools: stainless steel, titanium, steel 1.4404, stainless steel with wear-resistant coating
    Sieve sizes: trapezoid holes 0.08 / 0.12 / 0.20 / 0.25 / 0.50 / 0.75 / 1.00 / 1.50 / 2.00 mm // round holes 3.00 / 4.00 / 5.00 / 6.00 / 10.00 mm
    Setting of grinding time:
    Collector capacity: 900 ml with standard cassette // 50 ml with mini-cassette // 3000 ml with paper filter bag // 5000 ml / 3000 ml / 500 ml / 250 ml with cyclone
    Drive: 3-phase asynchronous motor with frequency converter
    Electrical supply data: different voltages
    Power connection: 1-phase
    Protection code: IP 20
    Power consumption: 1300 W
    W x H x D closed: 410 x 515 x 365 mm
    Net weight: ~ 38 kg
    Standards: CE

    Quick View Details