RADIATION, HEAT–Heat emitted in the form of heat
waves.
REACH RODS–A length of pipe used as an extension
on valve stems.
REACTION TURBINE–A turbine in which the major
part of the driving force is received from the reactive
force of steam as it leaves the bladingSee IMPULSE
TURBINE.
REDUCE–Any coupling or fitting that connects a
large opening to a smaller pipe or hose.
REDUCING VALVES–Automatic valves that provide
a steady pressure lower than the supply pressure.
REDUCTION GEAR–A set of gears that transmit the
rotation of one shaft to another at a slower speed.
REEFER–A refrigerated compartmental authorized
abbreviation for refrigerator.
REFRACTORY–Various types of heat-resistant,
insulating material used to line the insides of boiler
furnaces.
REFRIGERANT 12 (R-12)–A nonpoisonous gas used
in air-conditioning and refrigeration systems.
REGULATOR (GAS)–An instrument that controls the
flow of gases from compressed gas cylinders.
REMOTE OPERATING GEAR–Flexible cables
attached to valve wheels so that the valves can be
operated from another compartment.
RISER–A vertical pipe leading off a large horizontal
pipe; for example, a fire main riser.
ROTARY SWITCH–An electrical switch that closes
or opens the circuit by a rotating motion.
ROTOR–The rotating part of a turbine, pump, electric
motor, or generator.
SAE–Abbreviation for the Society of Automotive
Engineers.
SAFETY VALVE–An automatic, quick opening and
closing valve that has a reset pressure lower than the
lift pressure.
SALINITY–Relative salt content of water.
SALINOMETER–A hydrometer that measures the
concentration of salt in a solution (brine density).
SATURATION PRESSURE–The pressure
corresponding to the saturation temperature.
SATURATION TEMPERATURE–The temperature
at which a liquid boils under a given pressureFor
any given saturation temperature, there is a
corresponding saturation pressure.
SCALE–An undesirable deposit, mostly calcium
sulfate, that forms in the tubes of boilers and
distilling plants.
SECURE–To make fast or safe-the order given on
completion of a drill or exercise. The procedure
followed when any piece of equipment is to be shut
down.
SENTINEL VALVES–Small relief valves used
primarily as a warning device.
propeller shafts pass through.
SHAFT ALLEY–The compartment of a ship that
SKETCH–A rough drawing indicating
of an object.
major features
SLIDING FEET–A mounting for turbines and boilers
that allows for expansion and contraction.
SLUDGE–The sediment left in fuel oil tanks, lube oil
sumps, and boiler water drums.
SOLID COUPLING–A device that joins two shafts
rigidly.
SOOT BLOWER–A soot removal device that uses a
steam jet to clean the fire sides of a boiler.
SPECIFIC HEAT–The amount of heat required to
raise the temperature of 1 pound of a substance
1$FAll substances are compared to water that has a
specific heat of 1 Btu/lb/°F.
SPEED-LIMITING GOVERNOR–A device that
limits the rotational speed of a prime mover.
SPEED-REGULATING GOVERNOR–A device that
maintains a constant speed on a piece of machinery
that is operating under varying load conditions.
SPLIT PLANT–A method of operating an electrical or
propulsion plant so that it is divided into two or more
separate and complete units.
SPRING BEARINGS–Bearings positioned at varying
intervals along a propulsion shaft to help keep it in
alignment and to support its weight.
STANDBY EQUIPMENT–Two identical auxiliaries
that perform one functionWhen one auxiliary is
running, the standby is connected so that it maybe
started if the first fails.
STATIC–A force exerted by reason of weight alone as
related to bodies at rest or in balance.
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