Variable Speed Fritsch Sample Preparation

Preparing a range of sample materials, with different physical and chemical properties can be difficult at the best of times. To overcome the challenges presented by milling soft to medium hard sample materials, Fritsch offer greater flexibility and control with variable speed cutting and rotor mills. Which can be used for to prepare sample materials with a particle size range from 20mm, down to 0.08mm.



Fritsch Variable Speed Pulverisette 19 Cutting Mills

There are two Fritsch variable speed Pulverisette 19 cutting mills:

1. High variable speed Pulverisette 19 cutting mill, has an adjustable speed of 300-3000rpm, in 100rpm increments and a rotational torque of up to 30Nm. This instrument is ideal for milling dry soft to medium-hard sample materials such as animal feeds, bones, wood, non-metallic waste, dried meat and straw and can be used for fibrous materials and plastics. Adjusting the speed in 100rpm increments means that the sample preparation process can be finely tuned for a wide range of different and difficult sample materials.

2. Low variable speed Pulverisette 19 cutting mill, has an adjustable speed of 50-700rpm, in 10rpm increments and a rotational torque of up to 67Nm. A combination of a slower cutting speed and a greater force of rotation means that hard, tough and elastic sample materials can be processed through this instrument. It is an ideal sample preparation solution for applications where: thermal damage, loss of volatile organic compounds or the generation of a high percentage of fines needs to be avoided.

The grinding chamber of the Pulverisette 19 houses a rotor, which in combination with the three fixed blades (in the grinding chamber wall) gives the initial material size reduction. The three fixed blades are set at different angles, which means that the material is both crushed and ground before it is carried (by the permanent air flow through the instrument) to the sieve cassette. Sieve cassette sizes for the Fritsch Pulverisette 19 cutting range from 20mm down to 0.2mm.

The Pulverisette 19 cutting mills are available on a stand or bench mounted and can be supplied with either a single or three-phase motor. The Pulverisette 19 cutting mills can be used to prepare larger sample volumes than the rotor mill, down to a minimum particle size of 0.2mm depending on the sample material.


Variable Speed Rotor Mill Pulverisette 14

The Fritsch Classic Line Pulverisette 14 variable speed rotor mill is a bench top instrument with the following dimension: (w x d x h) 31 x 48 x 47cm. It has a variable speed rotor, operating at speeds between 6,000-20,000rpm, which is adjustable in 1,000rpm increments. It can be used to mill a variety of soft to medium hard materials, including fertilisers, plants, roots, peas, leather, rice and pepper seeds.

The Pulverisette 14 variable speed rotor mill can be used to mill material, which requires embrittlement with dry ice or liquid nitrogen, prior to milling. The final material fineness is determined by the size of the sieve ring used in the instrument, which ranges from 6mm to 0.08mm.

The Fritsch Pulverisette 14 variable speed rotor mil rapidly and efficiently crushes the sample material using a combination of force, shear and friction (between the rotor blades and the sieve ring). The final material fineness is determined by the size of the sieve ring used in the instrument, which ranges from 0.08mm to 6mm. Heavy duty material can also be milled, by using sieve rings with reinforced edges.


Fritsch Cyclone Sample Collection

To increase the flexibility of both the cutting and rotor mills, Fritsch supply a cyclone system, which is ideal for the preparation of temperature sensitive sample materials, such as polymers and powder coatings, or for soft and fatty samples with residual moisture.

The powerful air vortex used in the cyclone separator, has a number of benefits:

  • The sample material is cooled during milling.
  • Greater sample throughput.
  • Dust free sample preparation.
  • Reduced heat build-up on the rotor.
  • An ultra-fine HEPA dust filter, prevents clogging of the sieve ring.
  • It draws the sample material into a glass collection bottle.
  • Reduced sample contamination on the grinding parts.

As a standard, the cyclone separator is supplied with a 500ml glass collection bottle, 1 litre, 2 litres and 5 litres glass collection bottles are also available.