DRILSMOOTH: Mixed Metal Oxides Drilling Fluids System


DRILSMOOTH is a mixed metal oxide (MMO) rheology modifier and secondary shale stabilizer designed to provide excellent shear-thinning, carrying capacity, and suspending ability. Improving shale stabilization and solids tolerance, this viscosifier can be blended with bentonite to produce a thermally stable, shear-thinning fluid with a high yield point, low plastic viscosity, and fragile gels for a variety of fresh and salt water systems.

The DRILSMOOTH system is often chosen for managing drilling fluids circulation losses because of its well-documented cuttings-carrying capacity and its ability to control losses in permeable and porous formations. The system is also ideal for unconsolidated formations, milling, high-angle and horizontal wells, top hole drilling, workover jobs, and geothermal drilling. The high viscosities achieved at lower shear rates (3 and 6 rpm) allow excellent hole cleaning capabilities and suspension properties, and reduced flow through fractures.

System Components & Additives

Bentonite Premium, a high-purity, high-surface area untreated bentonite, is specified for use with MMO products. When a DRILSMOOTH product is added to a Bentonite Premium slurry, a unique cationic complex is formed which produces a very high yield point fluid with extreme shear-thinning characteristics.

DRILSMOOTH is a single package proprietary mixture of metal oxides and pH buffers that when added to Bentonite Premium produces a complete DRILSMOOTH system. DRILSMOOTH provides exceptional shear-thinning properties in Bentonite Premium fluids, with excellent dynamic and static carrying capacity.

MMO FLR is a fluid loss reducer for DRILSMOOTH. It consists of a modified starch that reduces fluid loss without negatively affecting system performance or rheology.

MMO AS is a concentrated cationic liquid which neutralizes organic anionic drilling fluid contaminants. Previous mixed metal systems experiencing organic anion contamination required displacing and replacing with fresh drilling fluids but adding MMO AS to DRILSMOOTH restores the rheological properties after the fluids become contaminated with negatively charged organic material.  In addition, the use of MMO AS improves fluids temperature stability.

We Deliver, No Excuses


High-penetration rates and return permeability

Improves thermal stability

High temperature rheology control

Optimal cuttings transportation

Minimizes disposal costs

Stabilizes unconsolidated formations

Excellent shale inhibition

Able to drill in any lithology

Higher yield with faster hydration and swelling


Water-based systems






PropertyTypical RangeMin/Max Recommended
Fluid weight (ppg)8.8 - 12.5< 12.5
Plastic Viscosity (cP)ALAPALAP
Yield Point (lb/100ft2)30 - 45< 70
Gels 10"/10' (lb/100ft2)20/30 - 30/50As required
pH9.5 - 10.59.8 - 10.5
API Fluid Loss (ml/30min)10.0 - 12.0< 15.0
Calcium (mg/l)80 - 150< 100
MBT (ppb-eq) 0 - 15.0< 15.0