Lube oil cooler
Heaters are of conventional shell and U-tube
design. Each heater is designed to raise the oil
Lube oil discharge filter
temperature from 40F to 90F at 30 gpm and
to 160F at 4 gpm.
Lube oil sump tank
Oil enters at one end of the shell and
makes one pass through the heater as directed
LUBE OIL SERVICE PUMPS.--The pumps
by the baffles. Ship's service steam enters
are two-speed, electric-motor-driven, vertically
one end of the tubes through the inlet con-
mounted, screw-type pumps. The controls allow
nection and makes one pass through the
either pump to be designated NORMAL with the
U tubes. Condensate is returned to the con-
other designated as STANDBY. The normal
densate collecting system through the con-
pump runs at low speed only for preheating the
taminated drain inspection tank. The steam
lube oil and runs at high speed during service
inlet valve is controlled by a temperature
conditions. With the pump controller mode switch
sensor located in the oil outlet.
in the AUTO position, operation of the pumps
is controlled by a set of pressure switches. If the
A temperature switch, sensing the oil
oil pressure to the reduction gear hydraulically
temperature at the heater outlet, opens at 170F
most remote bearing begins to drop below 13 psig,
and provides a signal for the ECSS. It is used to
a pressure switch closes and causes the standby
operate HEATER TEMP HI alarm lights at
pump to start operating at low speed. If the oil
the PACC and the PLCC and for alarm
pressure continues to drop below 11 psig, another
logging.
pressure switch closes and the standby pump
switches to high speed. A further drop in pressure
to 9 psig closes a third pressure switch. It also
FFG Lube Oil System
causes the pneumatically driven, coast-down
pump to start operating by opening the solenoid
The reduction gear lube oil service system
valve to the pump's air motor.
supplies oil to the propulsion reduction gear and
clutches for lubrication and cooling. The oil
When the oil temperature is below 90F,
supply also circulates through heat exchangers and
preheating is required. A connection to the lube
acts as a coolant for the GTE lube oil service
oil fill, transfer, and purifying system allows use
system.
of one of the lube oil service pumps to circulate
oil through the lube oil purifier heater. Priming
The reduction gear lube oil service system is
lines are provided at each pump so the operation
a closed loop system with the sump tank vented
of either service pump will maintain a continuous
to the atmosphere. Circulation of lube oil is
oil prime to the other two pumps. A relief valve
normally accomplished by one service pump with
set at 80 psig is located at each service pump
the other service pump on automatic standby. A
discharge to protect the system from
third pump that is pneumatically driven acts as
overpressurization.
a standby to the two service pumps and provides
an oil supply to the reduction gear in case of
LUBE OIL COAST-DOWN PUMP.--This
electrical power failure on the ship. The system
pump is a pneumatically driven, vertically
is initially filled by the lube oil fill, transfer, and
mounted, screw-type pump. If the propeller shaft
purifying system.
is rotating during an electric power failure on the
ship, the service pumps stop. The loss of pressure
The reduction gear lube oil service system
causes the lube oil coast-down pump to start and
includes the following components:
continue to run until the propulsion plant can be
secured. The duration of operation of this pump
Lube oil service pumps (2)
is limited by the quantity of air stored in the HP
air flasks provided in the engine room. The
Lube oil coast-down pump
discharge of the coast-down pump goes into the
reduction gear oil inlet header via the lube oil
Lube oil unloading valve
service filter. The discharge bypasses the rest of
the lube oil service system. A relief valve set at
Lube oil temperature-regulating valve
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