19. DAMPER - A device for regulating the flow of flue gases in a chimney, thus
controlling the amount of excess air to the furnace.
20. DOWNCOMER - The conduit or overflow pipe in a distillation tower through
which the liquid from one tray enters and is distributed to the tray below.
21. DRAW OFF - A connection which allows liquid to flow from the side or bottom
of a vessel.
22. ETHYL FLUID (Tetra-ethyl Lead) - A chemical which retards the tendency for
gasoline to pre-ignite in an internal combustion engine.
23. EXPANSION JOINT - A type of joint used in piping. It usually contains a
telescoping section or a bellows to absorb strain caused by expansion or
contraction due to changes of temperature or other forces.
24. FEED WATER - The water supplied to a boiler to make up for evaporation and
boiler blow down.
25. FIRE WALLS - Earthen banks or concrete walls built around storage tanks or
other equipment containing oil to prevent its spread in case of fire or run over.
26. FLOATING HEAD - The end of a heat exchanger bundle not attached to the shell
so as to allow for expansion.
27. FLUE GASES - Gases from the combustion of fuel. Their heating potential having
been substantially spent, they are discarded to the flue or stack. They consist
primarily of CO2-CO-O2-N2 and water vapor.
28. FOAMITE - A preparation used to extinguish fires. It consists of two solutions
which, on mixing, produce a thick foam which will cover a surface and smother a
fire.
29. FRACTIONATING TOWER - The vertical cylindrical vessel which separates
components of a liquid mixture in a distillation process.
30. FURNACE OIL - A light fuel oil primarily used in home heating systems.
31. GAUGE - To measure, such as to gauge the level in a tank. Also, an instrument for
measuring, such as a pressure gauge.
32. HEAD - Pressure of a fluid upon a system due to the height at which the surface
on the fluid stands above the point where the pressure is taken. The discharge
pressure of a pump is sometimes referred to as the pump head and expressed as
feet of fluid.
HEAD - The removable end plate of an exchanger or the bolted plate over a tower
or tank opening.
33. HEADER - A common manifold to which two or more pipes or tubes are
connected. Headers in a heater have plugs that can be removed for cleaning.
34. HEATER - A furnace used for heating oil or gas for a unit. The portion where the
burners are located is called the fire box or furnace. The fluid to be heated is
flowing through tubes in the heater. The tubes visible to the fires are called the
radiant section, and the tubes heated by combustion gases are called the convection
section.
