Technical
Thesaurus oil & gas
N
Naphtha
A range of distillates
covering the heavier end of the gaseous fuel and the lighter end of the
kerosene range.
Natural flow
Term used to describe the
flow of fluids from a well using only the natural energy of the reservoir and
produced fluids.
Natural gas
A mixture of light
hydrocarbons (generally mainly methane) found naturally in the Earth's crust,
often in association with oil (when it is known as associated gas).
Natural gas liquids (NGL)
Liquid hydrocarbons found
in association with natural gas.
Natural tar
It is the portion of
petroleum that exists in the semi-solid or solid phase in natural deposits. In
its natural state it usually contains sulphur, metals and other
non-hydrocarbons.
Navigation
Guidance of craft in terms
of direction and position; a dynamic process, requiring different orders of
accuracy in different contexts (positioning).
Navigation (sonic)
Navigation by means of
sound waves whether or not they are within the audible range. Also called
acoustic navigation.
Needle valve
A globe valve that
incorporates a needle-point disk to produce extremely fine regulation of flow.
Net income
The income from a project
that remains after payment of all costs, royalties, taxes, etc.
Net pay
The net thickness of
reservoir, within a hydrocarbon zone, that is capable of production.
Net tonnage
The gross tonnage of a
crude oil or LNG tanker, less the machinery, boiler and bunker, crew and stores
spaces. See gross tonnage.
Neutral zone
An area of empty desert
between
Neutralise
To add an acid to alkali,
or vice versa, until a chemically neutral state exists.
Nipple
A tubular pipe fitting
threaded on both ends and less than
Nipple up
In drilling, to assemble
the blowout preventer stack on the wellhead at the surface.
Nitrogen
The main inert component of
air; nitrogen compounds are present as impurities in most crudes, and can cause
discoloration of heavy gasolines and kerosenes.
Nonwoven fabric
A fabric made from
artificial fibres which have been melt-welded (melded) together rather than
woven.
Normal circulation
The smooth, uninterrupted
circulation of drilling fluid down the drill stem, out the bit, up the annular
space between the pipe and the hole, and back to the surface. See mud
circulation and reverse circulation.
Northing
The distance a craft makes
good to the north. The opposite is southing. In certain reference system the
value of one coordinate, usually expressed in metres, measured from the origin
in north/south direction; e.g. used in the UTM system.
Norwegian trench
The region of extremely
deep water that lies just off the SW and S coasts of
Nowcast
The expected wind, wave and
weather conditions during the next few hours.
NYMEX