The volume and type of solids in a drilling mud system can adversely affect mud properties, reduce penetration rates, cause damage to drilling equipment, and increase total drilling costs. Efficiency controlling the solids content of the mud system is an important phase of an efficient and cost-effective drilling program. The three basic methods of removing solids are dilution and/or displacement of whole mud, settling and mechanical solids-control equipment.
During a drilling operation, drilled solids or cuttings generated at the bit mix and interact with the initially formulated drilling fluid and bring about changes in its density, rheology, and other properties. These changes are affected by such factors as the flow-rate, density, size distribution and the degradation tendency of the drilled solids These factors, in turn, are determined by such interacting variables as lithology, fluid properties, penetration rate, and the wellbore geometry.
Proper application and utilization of mechanical solids control equipment enables the driller to maintain the desired drilling fluid properties which in turn makes it possible for the drilling operation to be carried out in an efficient and possible for the drilling operation to be carried out in an efficient and economical manner.