heads or sprinkler-head valves. They are arranged so
REVIEW QUESTIONS
the water forced through them showers all parts of the
magazine or ammunition and missile-handling areas.
Q1.
The firemain system is used primarily to
A modern sprinkler system can wet down all exposed
supply seawater to what other systems?
bulkheads at the rate of 2 gallons per minute per square
foot. It can sprinkle the deck area at the rate of 4 gallons
1.
Bilge and heating
per minute per square foot.
2.
Air-conditioning and main power
Magazine sprinkler systems can completely flood
3.
Boiler and auxiliary power
their designated spaces within an hour. To prevent
unnecessary flooding of adjacent areas, all
4.
Fireplug and sprinkling
compartments equipped with sprinkler systems are
watertight. Upper deck handling and ready-service
Q2.
There is a total of how many basic types of
rooms are equipped with drains that limit the water
firemain systems designed for use on large
level to a few inches.
Navy ships?
The valves that control the operation of the
magazine sprinkler system are as follows:
1.
1
1. The manual control valve. This valve permits
2.
2
hydraulic operation of the sprinkler valve.
3.
3
2. The hydraulically operated remote control
4.
4
valve. This diaphragm operated globe type valve is
opened by operating pressure acting against the
Q3.
What type of firemain system is separated
underside of the disk and closed by operating pressure
both vertically and athwartship?
acting on top of the diaphragm. This valve permits the
sprinkler valve to be secured from other stations,
1.
Single-main
whether or not it was manually or automatically
2.
Horizontal
actuated.
3.
Auxiliary
3. The spring-loaded lift check valve. This
spring-loaded, diaphragm operated, lift check valve
4.
Vertical offset loop
closes tightly against the reverse flow and opens wide to
permit flow in the normal direction. Spring-loaded lift
Q4.
Sprinkler systems are used for emergency
check valves permit the control system to be operated
cooling of, and fire fighting in, magazines,
from more than one control station by preventing
ready-service rooms, ammunition, and missile
backflow through the other stations.
handling areas.
4. The hydraulically operated check valve. This
valve permits the operating pressure to be vented from
1.
True
the diaphragm chamber of the magazine-sprinkling
2.
False
valve, thereby permitting that valve to close rapidly and
completely.
Q5.
What are the two basic types of hydraulically
5. Power operated check valve. This piston
controlled sprinkler systems used on naval
operated poppet type valve is opened by pressure from
ships?
the "close" loop of the actuating pressure acting against
the piston.
1.
The reciprocal and jet types
The Gunner's Mates assigned to a ship's company
2.
The pump-operated vacuum and the full
maintain the magazine sprinkler systems. However,
bore types
personnel in the Damage Controlman rating must
3.
The firemain-operated dry type and the
consider what effect their maintenance or repair on the
firemain-operated wet type
firemain system will have on the magazine sprinkler
4.
The main power and auxiliary power types
systems.
6-3
