Page 327 - Shale Shakers Drilling Fluid Systems

GLOSSARY 309

commercial colloids, and lost circulation materials. Salt is considered a
low specific gravity solid. See: Heavy Solids, High-Gravity Solids.

Low-Silt Drilling Fluid An unweighted drilling fluid that has all the sand and most of the silts
removed and contains a substantial content of bentonite or other water-
loss reducing clays.

Low-Silt Mud See: Low-Silt Drilling Mud.

Low Solids Drilling Fluids A drilling fluid that has polymers, such as CMC or XC Polymer, partially
or wholly substituted for commercial or natural clays. For comparable
viscosity and densities, a low-solids drilling fluid will have a lower vol-
ume percent solids content. In general, the lower the solids content in a
mud, the faster a bit can drill.

Low-Solids, Non-Dispersed A drilling fluid to which polymers have been added to simultaneously
(LSND) Drilling Fluids extend and flocculate bentonite and drilled solids. These fluids contain
low concentrations of dispersed bentonite and do not contain defloc-
culants such as lignites, lignosulfonates, and the like.

Low-Solids Muds See: Low-Solids Drilling Fluids.

Low-Yield Clay Commercial clay, specifically the calcium montmorillonite type, having a
yield of approximately 15 to 30 barrels per ton. See: High-Yield Clay,
Bentonite.

Lyophilic Having an affinity for the suspending medium, such as bentonite in water.

Lyophlic Colloid A colloid that is not easily precipitated from a solution and is readily
dispersible after precipitation by an addition of a solvent.

Lyophobic Colloid A colloid that is readily precipitated from a solution and cannot be re-
dispersed by addition of the solution.

Main Shaker The shale shaker that processes drilling fluid from the flow line through
the finest mesh screen.

Manifold (1) A length of pipe with multiple connections for collecting or distribut-
ing fluid. (2) A piping arrangement through which liquids, solids, or slur-
ries from one or more sources can be fed to or discharged from a solids
separation device.

Market Grade Cloth A group of industrial wire cloth specifications selected for general purpose
work, made of high strength, square mesh cloth in several types of metals.
The common metal for oil field use is 304 or 316 stainless steel. The wire
diameters are marginally larger than mill grade cloth, resulting in a lower
percentage of open area. Market grade and mill grade clothes are used
mostly as support screens for fine mesh screens. See: Mill Grade Cloth, Ten-
sile Bolting Cloth, Ultra Fine Wire Cloth, Support Screen, Calendered.

Marsh Funnel An instrument used in determining the Marsh funnel viscosity. The Marsh
funnel is a container with a fixed orifice at the bottom so that when filled
with 1,500 cc freshwater, 1 qt (946 ml) will flow out in 26 ± 0.5 sec. For
1,000 cc out, the efflux time for water is 27.5 ± sec. It is used for compari-
son values only and not to diagnose drilling fluid problems. See: API Bulle-
tin RP 13B, Funnel Viscosity, Marsh Funnel Viscosity, Kinematic Viscosity.