Hydrocyclone separator

A hydrocyclone separator for classifying solid material in liquid suspension, comprising a head part having an inlet conduit adapted to feed a suspension into the head part, and having an overflow discharge tube arranged axially into the head part, a conically tapered separation part, an adjustable apex discharge port, and a tail pipe, wherein the adjustable apex discharge port comprises:

• an abrasive-resistant resilient body having a first section with a central tapered conical aperture forming a continuation of an inner wall of the conically tapered separation part, an apex orifice port, and a second section with a central aperture with a first end of the second section facing the apex orifice port and a second end of the second section facing and in communication with the tail pipe, wherein the second section has a central aperture having a frusto-conical form with a wider diameter in the second end than in the first end thereof, wherein the apex orifice port has a narrowest inner diameter of the abrasive-resistant resilient body;
• and
• an adjustment sleeve configured to circumferentially enclose the abrasive-resistant resilient body in an axial extension comprising the apex orifice port, with a first adjustment sleeve end circumferentially enclosing the first section, and a second adjustment sleeve end circumferentially enclosing the second section, which adjustment sleeve has a tapered conical surface configured to directly abut an outer surface of the abrasive-resistant resilient body, and which adjustment sleeve is arranged for axial displacement along the abrasive-resistant resilient body such that the direct contact between the tapered conical surface and the outer surface of the abrasive-resistant resilient body varies the size of the apex orifice port as a result of the axial displacement, wherein
• the second adjustment sleeve end is arranged so that the second end of the second section at least is aligned with or extends beyond the second adjustment sleeve end and into the tail pipe.