Desanders and desilters are drilling rig equipment with a set of hydrocyclones that separate sand and silt from the drilling fluids. Usually the desanders are used to romove the sand that drilling mud shale shaker can't remove, drilling fluids desilter is installed after desander to remove much smaller sand and silt. The hydrocyclones of them are the main and most important components.

A hydrocyclone has two exits on the axis: the smaller on the bottom (underflow or reject) and larger at the top (overflow or accept). The underflow is generally the denser or thicker fraction, while the overflow is the lighter or more fluid fraction.
 

Hydrocyclones are simple mechanical devices, without moving parts, designed to speed up the settling process. Feed pressure is transformed into centrifugal force inside the cone to accelerate particle settling in accordance with Stoke’s Law. In essence, a cyclone is a miniature settling pit that alloys rapid settling of solids under controlled conditions. Hydrocyclones have become important in solids control systems because of their ability to efficiently remove particles smaller than the finest mesh screens. There are a number of industrial claims that indicate that hydrocyclones can achieve solid cuts lower than 25μm, however when it comes to the practical installation and use of solids control systems (i.e. relative to pump impeller wear, drilling fluids viscosity, internal hydrocyclone wear, etc.) operators should conservatively assume 30μm as the performance limit.

Drilling mud enters the cyclone under pressure from a centrifugal pump. The velocity of the mud causes the particles to rotate rapidly within the main chamber of the cone (i.e. like a tornado in a bottle). Light, fine solids and the liquid phase of the mud spiral inward and upward for discharge through the liquid outlet. Heavy, coarse solids tend to spire outward and downward for discharge through the solids outlet or under flow.

KOSUN provides drilling mud desanders and desilters with hydrocyclones, which are all the high-performance solids control equipment. As a professional manufacturer of solids control equipment and drilling fluids systems, KOSUN can also supply other products and services for oilfield, including drilling mud shale shaker, vacuum degasser, desander, desilter, oilfield decanter centrifuge, drilling mud centrifugal pump, mud agitator, jet mud mixer and mud gun, etc.