low speed to high speed if the pressure is below 40 psig
will briefly discuss some of the major control and
monitoring systems.
and in the auto advance mode. The operator must
manually reset the pump to low speed.
Fuel Oil service System
The fuel pressure entering the GTE is monitored on
an edgewise meter located on the PCC. The supply
The fuel oil service system supplies fuel to the
cutoff valve control at the PCC is provided by an
GTEs. The control and monitoring functions available
alternate-action switch. his switch is inoperative when
at the PCC can be divided into two major categories: (1)
local lockout is in affect. The fuel oil supply cutoff valve
fuel oil service and (2) GTM fuel oil. Together they
is a normally-closed, energized-open valve that fails to
function to deliver fuel oil at the proper pressure and
the closed position upon loss of power. A split-legend
temperature to the individual propulsion GTEs.
indicator on the PCC provides the status of the fuel
The following eight fuel oil service monitoring and
supply cutoff valve.
control functions are available at the PCC:
The gas turbine emergency supply valve is a
1. Fuel oil service tank level monitoring
normally-open, energized closed valve that fails to the
open position upon loss of electrical power. A
2. Fuel oil service tank suction and return valves
split-legend indicator at the PCC provides the status of
monitoring and control
the emergency fuel supply valve.
3. Service pump suction valve monitoring
4. Service pump control and monitoring
Lube Oil System
5. Service pump discharge valve monitoring
The reduction gear lubricating oil service system
6. Fuel oil heater discharge temperature
consists of two main parallel branches, each containing
monitoring
a pump and a relief valve. An air motor drives a
7. Fuel oil prefilter strainer differential pressure
coastdown pump that provides lube oil automatically
monitoring
upon loss of electrical power to both lube oil pumps.
8. Fuel oil filter/separator differential pressure
The right most panel on the PCC center section is
monitoring
the auxiliary panel that provides the control and
monitoring for the MRG lube oil system. The normal
The following three GTE fuel oil monitoring and
pump assignment signal to the indicator on the PCC
control functions are available at the PCC:
comes from the position of the local transfer switch at
1. Emergency fuel supply valve monitoring
the lube oil service pump control station. The manual
2. Supply cutoff valve control and monitoring
mode requires the operator to start, stop, or change
speeds of the normal and standby pumps. The auto speed
3. Fuel supply pressure monitoring
advance mode increases the speed of the normal pump,
PCC control of the fuel oil service system consists
starts the standby pump, and increases the speed of the
of remote control of the suction and return valves and
standby pump to maintain lube oil pressure. Lube oil
automatic or remote manual control of the fuel oil
pressure is monitored at the most remote bearing for the
service pumps.
auto speed advance mode. The auto speed advance
The suction and return motor-operated valves are
mode has no control features, however, to reduce the
electrically connected so when the tank suction valve is
speed or stop either pump. Reducing the speed or
opened, the return valve also opens. An OPEN/CLOSE
stopping either pump is a manual operation, regardless
alternate-action push button controls the valves from the
of the position of the mode switch.
PCC. The split-legend indicator provides the OPEN or
CLOSE status of the valves.
The PCC propulsion control panel provides a mimic
layout of the MRG with 29 indicators representing the
The fuel oil service pump operation can be
28 gearbox bearings and the one line shall bearing. All
controlled at the PCC in either the auto speed advance
the bearing temperature alarms are set at 20 degrees
or the manual mode. The operator selects low speed,
above the maximum full power builder trial data
high speed, or stop by depressing the corresponding
specified for each ship.
switch in the manual mode. The pump will advance from
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