HM 200 Hammer Mill

Hammer mills are used for crushing, pulverizing and deagglomeration of medium-hard, hard, brittle, tough and fibrous samples.

The rugged RETSCH Hammer Mill HM 200 accepts large feed sizes up to 100 mm which can be reduced to less than 0.8 mm, depending on the sample properties.

The mill is ideally suited for processing large volumes batchwise or continuously which ensures high sample throughput. Thanks to features like rugged design, easy handling and quick cleaning, the HM 200 is equally suitable for use in laboratories or pilot plants.



Easy cleaning of the rotor and the hammers thanks to

  • Fold-back hopper to gain access to the crushing chamber from above
  • Additional fold back option in the middle section of the machine allows easy cleaning of rotor and hammers from below

To ensure a long service life of the machine, even when mostly used for tough crushing tasks, the following parts can be exchanged by the user:

  • Wear plates inside the mill
  • Rotor with the swing hammers

A safety switch and the brake motor ensure that the unit comes to an immediate stop, e.g. if the door is openend unintentially.


This diagram shows a comparison of the Hammer Mill HM 200 with two rotor mills, the SK300 Cross Beater Mill and the SR300 Rotor Beater Mill. The extremely high sample throughput of the HM 200 is clearly visible. The HM 200 shows a good crushing efficiency of 125, which is the value of the maximum feed size divided by the finest achievable grind size. The SR 300 and SK 300 accept a maximum feed size of 25 mm (unlike the HM 200 which accepts sizes up to 100 mm) and crush particles to a size below 0.05 mm or 0.1 mm respectively – resulting in a higher crushing ratio.

Benefits at a glance

  • Excellent crushing performance
  • Very high throughput of up to 1500 kg/h
  • Fixed speed of 3000 min-1
  • Sieve range from 2 – 40 mm
  • Feed size up to 100 mm, grind size < 0.8 mm
  • Easy access to crushing chamber facilitates cleaning
  • For batchwise or continuous grinding
  • Connector for dust extraction


The achievable final fineness of the sample depends on the material’s properties. Hard and brittle materials can be easily crushed in the HM 200 down to particle sizes below 0.8 mm. The range of sieves with aperture sizes from 2 mm to 40 mm allows for perfect adaption to application requirements.

Tough, fibrous, or moist samples like plastic toys, wood or humid coal can be successfully crushed in the hammer mill when choosing a sieve with medium to large aperture size.


The HM 200 is suitable for batchwise as well as continuous grinding and can be equipped with different hoppers and collecting systems.

  • Standard hopper for quick and easy feeding of large sample amounts
  • Batch hopper for feeding approximately 600 ml in one go with very little dust development
  • Standard collector for size reduction of sample amounts up to 10 l
  • For large volumes a collector is available which accommodates up to 30 l
  • Continuous operation: Use the continuous gravity outlet and a customer specific collecting system


RETSCH’s powerful hammer mill is ideally suited for preliminary crushing and fine grinding of ores, granite, ceramics, quartz, slag, soil, coal, glass, cement clinker, wood, plastics, feed pellets, dry animal feed, dried herbs etc.

Animal Feed
Herbs and Plants



Applications coarse and pre-crushing, desagglomeration
Field of application agriculture, chemistry / plastics, coal, construction materials, engineering / electronics, environment / recycling, food / feed, geology / metallurgy, glass / ceramics
Feed material medium-hard, hard, brittle, tough, fibrous
Size reduction principle impact, shearing
Material feed size* < 100 mm
Final fineness* < 0.8 mm
Batch size / feed quantity* < 0.6 l with batch hopper; 30 l with standard hopper
Speed at 50 Hz (60 Hz) 3000 min-1 (3500 min-1)
Throughput* 1500 kg/h
Rotor peripheral speed 31.4 m/s
Rotor diameter 200 mm
Types of rotors 10 swing hammer
Dry grinding yes
Wet grinding no
Cryogenic grinding no
Material of grinding tools hardened steel 1.0503 (hammers); steel 1.0330 (sieves)
Sieve sizes 2 / 3 / 4 / 5 / 6 / 8 / 10 / 15 / 40 mm
Dust extraction unit yes
Process line version yes
Collector capacity 10 l, 30 l, continuous outlet
Drive 3-phase motor
Drive power 1.5 kW
Electrical supply data different voltages
Power connection 3-phase
Protection code IP 54
W x H x D closed 320 x 960 x 800 mm
Net weight ~ 150 kg
Standards CE

*depending on feed material and instrument configuration/settings


Functional Principal

A hopper leads the sample material into the grinding chamber of the hammer mill.
The HM 200 is equipped with a horizontal rotating shaft on which 10 freely swinging hammers are mounted. Those hammers crush the material at high speed inside the grinding chamber. With the swing hammers in contrast to fixed hammers, the risk of blocking the machine as well as the wear is minimized. The material is crushed by impact when hit by each hammer and while bouncing inside the grinding chamber. As soon as the sample is fine enough to pass through the sieve, it falls through the gravity outlet into a collecting vessel.