CATHODIC PROTECTION A method for pre-
venting the corrosion of metals by electrolysis.
CENTRIFUGAL Moving or tending to move away
from the center axis of a rotating or turning object.
CENTRIFUGAL PUMP A rotating device that
moves liquids and develops liquid pressure by im-
parting centrifugal force.
CENTRIFUGAL PURIFIER A rotating device that
cleans fuel by using centrifugal force.
CLEAR AND BRIGHT Term for uncontaminated
fuel; indicating a complete absence of haze, free
water, or particulate matter that would be visible to
the naked eye.
CLEAVAGE The point of interface between two dif-
ferent liquids, such as oil and water.
CLOUD POINT The temperature at which a fuel
develops a cloudy or hazy appearance due to the
precipitation of wax or moisture.
COALESCER A tube (unit or element) that unites
water droplets when fuel passes through it.
COFFERDAM The space surrounding the MOGAS
storage tanks aboard ship; a watertight box.
COMBUSTIBLE LIQUID A liquid having a flash-
point at or above 100°F.
COMMINGLING Tie mixture of two or more pe-
troleum products resulting from improper handling,
particularly in pipeline or tanker operations.
CONSOLIDATE To merge into one. To consolidate
a nest of tanks means to pump the remaining fuel
from several partially empty tanks into a single
CONTAMINATION The addition of some material
not normally present in a petroleum product, such
as dirt, rust, water, or another petroleum product.
CONTINUITY To have a complete, uninterrupted
CORROSION The process of dissolving, especially
of metals, due to exposure to electrolytes.
CRUDE OIL Petroleum in its natural state.
CV Aircraft Carrier.
CVN Aircraft Carrier (nuclear-powered).
DAY TANK Fuel storage tank used for daily issue of
DEADMAN CONTROL A control device requiring
manual operation, such as a switch or valve, de-
signed to stop flow if the operator releases it.
DIAPHRAGM Separating device of rubber compo-
sition used to regulate all hydraulically operated
DIFFUSE To spread widely, scatter,
DIFFUSER A mechanical device used to diffuse.
DIKE An embankment or wall, usually of earth or
concrete, surrounding a storage tank to impound the
tanks contents in case of a leak or spill.
DISSOLVED WATER Water absorbed into the fuel
that is not visible. The amount of dissolved water a
fuel will hold depends upon the fuels temperature.
DISTILLATE Common term for several fuels ob-
tained directly from distillation of crude petroleum;
typically includes kerosene, JP-5, light-diesel, and
other light-burner fuels.
DOUBLE-WALLED PIPING Piping with two in-
dependent chambers, one surrounding the other (an
inner and an outer). Typically used in shipboard
gasoline systems. The inside chamber carries the
fuel, the outside chamber holds a protective gas
(such as CO? or N?).
DOWNGRADE To designate a fuel for a lesser pur-
pose than originally specified, often because of
EARTHING See GROUND.
EDUCTOR A jet-type pump with no moving parts.
An eductor moves liquid by entraining the pumped
liquid in a rapidly flowing stream of water (venturi
effect). Normally used to dewater bilges and tanks.
EMULSION The suspension of fine droplets of one
liquid in a second liquid with which the first will
ENTRAINED WATER Free-water contaminant in a
fuel in the form of very small droplets, fog, or mist.
It may or may not be visible.
EVAPORATE To change into vapor.
EVAPORATION LOSS Loss of liquid petroleum
into the atmosphere caused by evaporation.
FILTER A porous object through which a liquid
is passed to remove unwanted particles of solid