Sample preparation
Rotor mills
The rotor mill uses a high-speed toothed rotor that refines a tough or semi-hard sample through friction and impact. The perforated rasp that surrounds the rotor allows the sample to leave the grinding chamber of the rotor mill once it has reached the desired fineness. A hammer mill finely pounds a sample between rapidly rotating hammers. The refined sample can leave the grinding chamber through a sieve. A mortar mill is basically the automated version of manual refining in a mortar using a pestle. In the mortar mill, the distance and pressure between the mortar and pestle are adjustable. By proper material selection of mortar and pestle, contamination of the sample can be avoided.
Pulverisette 14 centrifugal rotor mill
The Pulverisette 14 centrifugal grinder is a universal mill for grinding fibrous and medium-hard materials. It is also possible to grind temperature-sensitive materials such as polymers. This is possible because of the short residence time in the grinding chamber and the cooling created by the high rotational speed of the rotor. If this cooling is still not sufficient, it is also possible to connect a cyclone extraction system. This option provides extraction of the ground material and reduces cleaning. In addition, cryogenic grinding using liquid nitrogen or solid CO2 is also possible.
Pulverisette 14 cutting and rotor mill
The FRITSCH rotor mill P-14 offers impact, shearing and cutting in one instrument – with higher performance, better cooling and is significantly quieter than comparable instruments. The powerful motor is ideal for particularly fast grinding of soft to medium-hard, brittle and fibrous materials and temperature-sensitive samples with extremely fast sample throughput, which can be further increased by using FRITSCH cyclone separators.
Its high performance makes the P-14 the ideal rotor mill for sample-scale grinding in the plastics industry.
Pulverisette 16 hammer mill
In the Pulverisette 16, the material is fed into the grinding chamber through a hopper. In the grinding chamber, the material is ground by a combination of impact, shear and friction between the rotating rotor and the fixed teeth. When the material is fine enough, it falls through a sieve (range 0.12mm to 10mm) into the collection bin. The volume of the standard collection container is 5 litres. A 30-litre container is also available. The Pulverisette 16 is available in stainless steel and cast iron. Assuming a maximum start size of 20 mm, it can grind up to 80 l/h.
Pulverisette 2 mortar grinder
The Pulverisette 2 mortar mill works on the same principle as the manual mortar. The material is ground by pressure and friction between the pestle and mortar. Both the pressure horizontal direction and also in vertical direction can be controlled. The grinding of the material can proceed in several steps to reach a final fineness. A scraper ensures that the material is homogenised and reintroduced between pestle and mortar.
Depending on the hardness of the sample and the need for metal-free grinding, different grinding arrangements are chosen. Available are, for example, tungsten carbide, agate and zirconia and steel.