Some common problems of drilling desander cone

Separating solids of drilling fluids, hydrocyclones in different specifications work against different diameters and for different cleannesses.

Hydrocyclone is usually installed on the drilling mud desilter, desander and mud cleaner in oilfield drilling mud system. It is the most important component for them.

Oilfield drilling mud desander is used as the 2nd stage drilling fluid solids control equipment of drilling mud system.The oil drilling desander makes separations between 45 and 75 microns.

However, some problems may arise when adjusting the underflow outlet:

1. “Dry Underflow”: Relatively smaller outlet can pile a layer of dry silt between it and the balanced point. When ultra-fine solids enter, its water goes through the layer and dewatered solids block the outlet, causing dry plug. And this is called “dry underflow” adjustment.

2. “Wet Underflow”: Relatively larger underflow outlet can discharge conical rotating liquid. And this is called “wet underflow”.

3. “Radial” Discharge: Commonly, two flows move mutually reversely at the apex, one is the air inhaled and another the solid-content slurry discharging radially, forming an annular curtain there. Inhaled air keeps the outlet open and the cyclone efficient.


4. “Rope-like Discharge”: When the solid content excessively exceeds the designed capacity, the hydrocyclone is over-loaded and solids flow out outlet in a rope-like shape, making no air or annular curtain but a nozzle possible. Then, some solid phase within limits will turn around and out from vortex finder.