Desander
Desander is a solid removal equipment that uses Hydrocyclone principle for removing larger solids from drilling fluid. It is placed after degasser in sequence of fluid flow system on the rig. Degassed mud is injected into desander as a tangential flow. The centrifugal forces generated due to the movement of fluid through the hydrocyclone moves the solid particles outwards. The dispersed particles move downward in a spiral path as underflow while the cleaner and lighter density liquid mud travels up through a vortex in the center of the hydrocyclone, exiting through piping at the top of the hydrocyclone. Desander cones are usually available 8 – 12 inch diameter to remove drilling solid particles in 50 - 80 micron range. Hydrocyclones are made of polyurethane because of its wear resistance and less weight than steel.