| Tweet |
Custom Search
|
|
|
||
 TM 55-1925-273-10-1
OPERATOR'S MANUAL
INLAND AND COASTAL LARGE TUG (LT)
THEORY OF OPERATION
FUEL SYSTEM
GENERAL
The fuel oil system (figure 1) consists of four front mounted fuel filter/water separators, an engine mounted duplex fuel filter
set, a fuel supply manifold, and a fuel return manifold. The fuel pump draws in fuel from the day tank to the engine front
mounted fuel filter/water separator. Fuel passes through the filter element set to the fuel manifold of the fuel injection pump
housing. Fuel in the fuel manifold of the injection pump housing is the supply for the injection pumps. Injection pumps (one
per cylinder) send fuel to the fuel injection nozzle. A small amount of fuel is pumped into the cylinder, at a very high
pressure, through the needle valve and the spray tip of the injector. The amount of fuel injected depends upon the position
of the plunger, which is controlled by the injector rack and governor. Excess fuel flows through the fuel return manifold and
is then returned to the day tank. Excess fuel also cools and lubricates the injector.
FUEL OIL FILL AND TRANSFER PIPING SYSTEM
The fuel oil fill and transfer piping system (figure 2) replenishes the vessel's fuel oil tanks from deck discharge/fill connec-
tions. The system also replenishes fuel oil day tanks (PORT and STARBOARD) and the emergency diesel generator day
tank by transferring fuel oil from the storage tanks. System control is maintained through a manifold and a combination of
valves as shown in figure 2. Fuel oil can be transferred from any storage tank to any day tank and from one storage tank to
another. Power to fuel oil transfer pump 1 is supplied by the emergency switchboard and controlled by a local START/STOP
pushbutton and an emergency STOP switch located outside the engine room. Power to fuel oil transfer pump 2 is supplied
by the main switchboard through 440V power panel No. 1 and is controlled by a local START/STOP pushbutton and an
emergency STOP pushbutton located outside the engine room. Each pump shuts down upon activation of any FM-200
pressure switch (refer to WP 0032 00). Fuel oil purification is provided by a fuel filter/water separator between the manifold
and the fuel oil transfer pump.
0022 00-1
|
||
|
||
