Marine Installation Manual
2021-08
4-62
4 Ancillary Systems
4.5 Pilot fuel oil system
X72DF
Main components of
pilot fuel oil system
The main components of the pilot fuel oil system are the pump unit, common rail
pipe, feed pipes, and injection valves.
Pressurised pilot fuel is delivered from the pump unit into a common rail pipe.
The high-pressure piping from pump to injectors is of double-wall type. Any
leakage is collected from the annular space of the double-wall pipe and led to a
collector fitted with a leakage sensor. The common rail piping delivers pilot fuel
to each injection valve and in addition acts as a pressure accumulator against
pressure pulses.
Pilot injection valves
and pre-chambers
The X-DF engine uses pilot injectors with built-in solenoid valves. The injectors
are electronically controlled by the WinGD Engine Control System, which al
-
lows exact timing and duration of the injection. To have the best ignition and
combustion stability, the pilot injection valves are combined with pre-chambers.
These pre-chambers are directly cooled by the HT cooling water from the cyl
-
inder cover. Furthermore the injectors are cooled by system oil.
Pilot fuel injection is also activated in diesel mode operation to prevent excessive
deposit formation on the injector tips and in the pre-chambers.
Figure 4
-
38 Pilot fuel high-pressure system
High pressure pipes
Pilot fuel injectors
Pilot fuel pump
SM-0078
