Page 300 - Shale Shakers Drilling Fluid Systems

282 SHALE SHAKERS AND DRILLING FLUID SYSTEMS

Apex Valve See.- Apex, Underflow Opening.

API Bulletin RP 10B Recommended Practice for Testing Well Cement. Published by the Ameri-
can Petroleum Institute.

API Bulletin RP 13B Recommended Practice for Standard Procedure for Testing Drilling Flu-
ids at the rig. Published by the American Petroleum Institute.

API Bulletin RP 13C Recommended Practice for Drilling Fluid Systems Process Evaluation.
Published by the American Petroleum Institute.

API Bulletin RP 13E Recommended Practice for Shaker Screen Cloth Design. Published by the
American Petroleum Institute.

API Filter Press A device used to measure the fluid loss under API conditions. See: API
Fluid Loss.

API Fluid Loss This fluid loss is measured under ambient conditions. Usually these are
room temperature and 100 psi differential pressure. See.- API Filter Press.

API Gravity The gravity (weight per unit volume) of crude oil or other related fluids
as measured by a system recommended by the American Petroleum In-
stitute. It is related to specific gravity by the following formula: Degree
API = [141.5/Specific Gravity] - 131.5.

API Sand Solids particles that are too large to pass through a U.S. Standard No.
200 Screen (74 micron openings). See: API Bulletin RP 13B, Sand, Sand
Content.

Apparent Viscosity The apparent viscosity in centipoise, as determined by the direct indicat-
ing viscometer, is equal to one-half the 600 RPM reading. It is the vis-
1
cosity of a fluid at a shear rate of 1,022 sec- . See: Viscosity, Plastic Vis-
cosity, Yield Point, API RP 13B.

Aromatic Hydrocarbons Hydrocarbons that include compounds containing aliphatic or aromatic
groups attached to aromatic rings. Benzene is the simplest example. See:
Live Oil.

Asphalt A natural or mixed blend of solid or viscous bitumen found in natural
beds or obtained as a residue from petroleum distillation. Asphalt, blends
containing asphalt, and altered asphaltic materials (e.g., air-blown, chemi-
-
cally modified, etc.) have been added to drilling fluids f° purposes such
as lost circulation, emulsification, fluid loss control, lubrication, seepage
loss, shale stability, and so forth.

Atom The smallest quantity of an element that is capable of entering into
chemical combination or that can exist alone.

Atomic Weight The relative weight of an atom of any element as compared with the
weight of one atom of oxygen. The atomic weight of oxygen is 16.

Attapulgite Clay A colloidal, viscosity building clay used principally in saltwater drilling
fluids to increase the low shear viscosity. Attapulgite, a special fuller's
earth, is a hydrous magnesium aluminum silicate, which has long, needle-
like platelets as opposed to the broader, more symmetrical platelets
of bentonite.