one of three pumping systems. Each pumping system
Foilborne ACS for pressurization of components
consists of the following units:
and cabling
1. Four at-powered pumps
Windshield washer system for pressurization of
the window washing fluid storage tank
2. Two de-powered pumps, used as engine-starting
fuel delivery pumps and standby pumps
S e r v i c e outlets for varying maintenance
requirements
3. One emergency operation hydraulic pump
For operation and underway replenishment
S e a w a t e r system, hullborne diesel engine
operations, fuel system control is accomplished at the
seawater sea chest blowdown lines, and bilge
f u e l system panel at the EOS console. Defueling
drainage system for pressurized operation of
operations are manually controlled by operation of local
a i r - a c t u a t i n g valves and valve-actuating
and manually-operated valves. The onboard fuel can be
dewatered and the particulate removed by passing the
Pressurized air to the compressed air system is
fuel through an onboard fuel purifier. The fuel can be
supplied from the following two sources:
removed from any tank, passed through the purifier and
returned to any tank, including the tank from which the
1. Second-stage bleed air at a flow rate of 120 psi
fuel was originally removed. The fuel purification
at 600F from either of the two SSPUs. This is
process is controlled from either the FUEL PURIFIER
the primary source of compressed air. Passing
panel in the EOS or the FUEL PURIFIER LOCAL
through seawater-cooled condensers allows this
CONTROL BOX in auxiliary machinery room No. 2.
air supply to cool down to 86F.
The fuel purifier can process about 25 gallons of fuel
2 . Air compressor and tank assembly of the
per minute.
compressed air system at a flow rate of 60 to 90
psi. This is the secondary source of pressurized
HYDRAULIC POWER SYSTEM
air. It should be used only when the SSPUs are
not supplying a minimum airflow rate of 60 psi
To operate, the foilborne and hullborne controls,
or are supplying bleed air to the ship's
foils, capstan, and foilborne emergency fuel pump all
propulsion de-icing system.
r e q u i r e hydraulic power. Normally, the 3,000-psi
Pressurized air from both sources must be dried,
hydraulic power supply needed to meet these
filtered, and pressure-regulated as required before
requirements is provided by four separate systems. The
entering into the various systems and components.
two forward systems provide hydraulic power to the
bow. The two aft systems provide hydraulic power to
the stem.
SEAWATER SYSTEM
In the event of major damage, a dual hydraulic
power supply can be provided for each system function
The seawater system has two modes of operation:
with subsystem isolation forward and aft. If loss of
(1) foilborne and (2) hullborne. The PHM seawater
hydraulic pressure from the primary hydraulic source
system serves the following three primary purposes:
s h o u l d occur, hydraulic pressure for maintaining
1. Cooling machinery
foilborne operations is automatically supplied from the
standby source.
2. Lubricating propulsor bearings
3. Combating fires and other conditions involving
COMPRESSED AIR SYSTEM
overheating
The seawater system consists of four pumps. These
The compressed air system provides pressurized air
pumps provide cooling seawater to the diesel engines,
t o various components and systems that require
the SSPU heat exchangers, the SSPU bleed air coolers
pressurization to work properly. For example, these
of the compressed air system, the heat exchangers of
units, components, and systems must receive
the hydraulic power system, the heat transfer chiller of
pressurized air for the following purposes:
the environmental control system condenser, and the
Hydraulic power system for pressurization of the
gun assemblies. As indicated earlier, seawater is also
hydraulic reservoirs
supplied to the hullborne diesel engine propulsory for
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