BAKER HUGHES - Drilling Fluids Reference Manual

GLOSSARY OF TERMS
Lypophilic Colloid - A colloid that is not easily precipitated from a solution, and is readily
dispersible after precipitation by the addition of a solvent.
Lypophobic - A colloid that is readily precipitated from a solution and cannot be re-dispersed by
addition of the solution.
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 1500 cc freshwater, 1 qt (946
rnL) will flow out in 26 seconds. For 1000 cc out, the efflux time for water is 27.5 seconds. See API
RP 13B for specifications.
Marsh Funnel Viscosity - Commonly called the funnel viscosity, the Marsh Funnel viscosity is
reported as the number of seconds required for a given fluid to flow 1 qt through the Marsh funnel. In
some areas, the efflux quantity is 1000 cc. See API RP I3B for instructions. See also Kinematic
Viscosity
Meniscus - The curved interface between two immiscible phases in a tube, such as in a pipette or
graduated cylinder. Liquid volumes should be read at the bottom of a curved meniscus by alignment
of the bottom of the meniscus. For water and liquids that wet the glass, the meniscus is concave. For
nonwetting liquids, such as mercury, the meniscus is convex.
Mesh - A measure of fineness of a woven material, screen, or sieve; e.g.; a 200-mesh sieve has 200
openings per linear inch. A 200-mesh screen with a wire diameter of 0.0021 in. (0.0533 mm) has an
opening of 0.074 mm, or will pass a particle of 74 microns. See Micron.
Methylene Blue Test - A test to determine the amount of clay-like materials in a water-base drilling
mud based on the amount of methylene blue dye absorbed by the sample. Results are reported as
“MBT” and also as “lb m /bbl, bentonite equivalent” when performed to API specifications. See
Cation-Exchange Capacity (CEC).
M f - The methyl orange alkalinity of the filtrate, reported as the number of milliliters of 0.02 Normal
(N/50) acid required per milliliter of filtrate to reach the methyl orange end point (pH 4.3).
Mica - A naturally occurring flake material of varying size used in combating lost circulation.
Chemically, an alkali aluminum silicate.
Micelles - Organic and inorganic molecular aggregates occurring in colloidal solutions. Long chains
of individual structural units chemically joined to one another and lay side by side to form bundles.
When bentonite hydrates, certain sodium, or other metallic ions go into solution, the clay particle
plus its atmosphere of ions is technically known as a micelle. See Oil-Emulsion Water.
BAKER HUGHES DRILLING FLUIDS
REFERENCE MANUAL
REVISION 2006 15-30