Spiral classifier

It is used for classification – separating the finely ground particles from the coarser ground particles in a given pulp, i.e. the particles mixed with water.

A spiral classifier is a large trough that is installed at a given slope. It has one or two spirals (spikes) that rotate. The spirals are lined with wear-resistant tiles around their circumference.

The unclassified pulp is fed into the lowest part of the trough, on the left or right side, depending on the technological scheme. There a water surface of sufficient area is formed to allow the coarser ground particles to settle. The spirals, which are close to the bottom when rotating, transport these sands to the upper end of the trough, where they exit through an opening and are fed into the process circuit for further processing.

The fine particles together with the water flow over the leading edge of the classifier and into a process chute which is connected to the process circuit and the classified pulp is fed into the process circuit for further processing. The chute for classified pulp as well as the chute for sands do not belong to the classifier supply.

By adjusting the spirals in height, i.e. by moving away or closer to the bottom, its optimal action can be selected. The classifier is mounted on concrete columns or a metal structure. It does not require much maintenance. The wear-resistant tiles have a natural wear and tear and can be replaced if necessary.They are fixed with screws and this is easily done.