Ultrasonic Sieving in the Laboratory
The ultrasonic processor UIS250L is used for the acceleration of sieving processes alternatively or complementary to the classical low frequency vibrators. Especially in case of very fine powders ultrasound is often the only possibility to enable the sieving process at all.
Hielscher Ultrasonics has developed a worldwide unique technology especially for exciting common laboratory ring sieves (according to DIN ISO 3310/1 or ASTM E 11-95) with diameters of 200mm or 8 inch. A ring sonotrode that fits the sieve is excited by the ultrasonic processor UIS250L. The ring sonotrode (RIS) transmits the oscillation via the sieve frame to the screening surface. With the help of the clamping fixtures the neighboring sieves are also excited. In contrast to the ultrasonic sieving processes known until now, in which each sieve needs its own ultrasonic excitation, this is a very inexpensive and flexible solution.
Another advantage of this exciting principle is that the transducer is situated outside the material to be sieved. This technology can be used for dry or wet sieving, as well as for cleaning the sieves. The ultrasonic components can be retrofitted in already existing sieving towers and can even be used in combination with vibrators. In this case the delivery scope consists only of the ultrasonic processor UIS250L and the ring sonotrode, which will be fitted into the common laboratory ring sieves of most manufacturers.