Page 328 - Shale Shakers Drilling Fluid Systems

310 SHALE SHAKERS AND DRILLING FLUID SYSTEMS

Marsh Funnel Viscosity Commonly called funnel viscosity. The Marsh funnel viscosity is reported
as the time in seconds required for I qt of fluid to flow through a API
standardized funnel. In some areas, the efflux quantity is 1,000 cc. See:
API Bulletin RP 13B, Funnel Viscosity, Kinematic Viscosity, Marsh Funnel.

Martin's Radii The distance from the centroid of an object to its outer boundary. The
direction of this measurement is specified by the azimuth orientation of
the line (the radii in the 0°, 90°, 180°, and 270° angle from horizontal).

Mass The inertial resistance of a body to acceleration, considered in classical
physics to be a conserved quantity independent of speed. The weight of
a body is the product of the mass of the body and the acceleration of
gravity for the specific location. In space, the mass would stay constant
but the weight would disappear as the gravitational acceleration ap-
proaches zero.

MET See.- Methylene Blue Test.
Mechanical Agitator A device used to mix, blend, or stir fluids by means of a rotating impel-
ler blade. See.- Agitator, Mechanical Stirrer.

Mechanical Stirrer See: Agitator, Mechanical Agitator.

Median Cut The median cut is the particle size that reports 50% of the weight to the
overflow and 50% of the weight to the underflow. Frequently identified
as the D 50 point. See: Cut Point.

Medium (Solids) Particles whose diameter is between 74 and 250 microns.
Meniscus The curved upper surface of a liquid column, concave when the contain-
ing walls are wetted by the liquid, and convex when they are not wetted.

Mesh (1) The number of openings (and fraction thereof) per linear inch in a
screen, counted in both directions from the center of a wire. (2) An indi-
cation of the weave of a woven material, screen, or sieve. A 200-mesh
sieve has 200 openings per linear inch. A 200-mesh screen with a wire
diameter of 0.0021 inch (0.0533 mm) has an opening of 0.074 mm and
will pass a spherical particle of 74 microns in diameter. See: Micron.

Mesh Count A mesh count, such as 30 x 30 or often 30 mesh, indicates the number
of openings per linear inch of screen and is a square mesh. A designation
of 70 x 30 mesh indicates a rectangular mesh with 70 openings per inch in
one direction and 30 openings per inch in a perpendicular direction.
Mesh Equivalent The U.S. Sieve number as used in oil field drilling applications, which has
the same size opening as the minimum opening of the screen in use.

Methylene Blue Test (MBT) A test that serves to indicate the amount of active clay in a fluid system,
clay sample, or shale sample. Methylene blue is titrated into a slurry until
all of the negative charge sites are covered with the methylene blue. This
indicates the number of active charge sites present in the slurry. See.- Base
Exchange, Methylene Blue Titration, MBT, Cation Exchange Capacity, CEC.

Methylene Blue Titration Methylene blue is a cation that seeks all negative charges on a clay sur
(MBT) face after the surface has been properly prepared (see API RP13B). By
titrating with a known concentration, this test provides an indication of
the amount of clay present in the drilling fluid. See.- Methylene Blue Test,
MBT, Cation Exchange Capacity, CEC.