Wheat straw

Majority of straws have a length < 13 cm. Only a few with a max length < 20 cm have been found.

Complete sample amount got ground within 3 minutes. Because particles can pass the trapezoidal openings longitudinal, some particles can be found with a length of ~ 1 cm.

Only a small amount of sample use to be left inside the grinding chamber and can be removed rapidly by vacuuming with a soft brush. Even higher amounts of sample can be ground this way.

It is also possible to use sieve cassettes with even smaller openings for pre cutting of sample.

Variable Speed Rotor Mill PULVERISETTE 14 has been used for fine grinding of sample. With this machine, also a grinding of higher amounts of sample is possible.

For this ~ 101 g of sample, about 4 ¾ minutes have been required for a constant feeding of sample.

Feeding can be automatized with Vibratory Feeder LABORETTE 24 which can be connected to the Variable Speed Rotor Mill PULVERISETTE 14 as well.

After grinding, rotor and sieve ring are only lightly polluted. A grinding of higher amounts of sample is still possible. Cleaning can be performed rapidly by vacuuming with a soft brush.

Regarding the fineness of ground particles: Usually ground particles will have a d50 smaller as half of the size of the trapezoidal openings. For this, about 50 % of sample might be smaller as 40 µm (with a 80 µm sieve ring).