Hydrocyclones of this kind may be made from cast iron because of the abrasive nature of the mineral pulps or slurries passing through them. The interior of the hydrocyclone is therefore subjected to wear, which is often localized. For example, the cone of the hydrocyclone may exhibit excessive wear at its lower, narrow end while exhibiting negligible wear at its upper, wider end. This results in the entire cone having to be discarded despite only localized wear having occurred.
A typical prior art cast iron hydrocyclone is shown in FIG. 1. The various parts of the hydrocyclone such as the inlet head (a), vortex finder (b), and cone (c) are joined together by means of slotted integral flanges (d). The slots on co-operating flanges align and receive bolts (e) which are tightened to hold the parts together. Where such a flange cracks or breaks the entire part has to be discarded.