Marine Installation Manual
2021-08
4-53
4 Ancillary Systems
4.4 Fuel gas system
X72DF
The iGPR consists of the following main components:
Fuel gas pressure
regulating valve
The fuel gas feed pressure to the engine must be adjusted within a narrow,
load-dependent pressure range. This adjustment will ensure that the fuel gas
pressure in the engine’s common-rail piping fits to the load command. This is
done by means of a pressure regulating valve that is controlled by the ECS.
Fuel gas shut-off valves
The fuel gas shut-off valves as installed in the iGPR are normally closed type
valves which are open during gas operation. It is used to shut off the fuel gas
supply to the pressure regulating valve and the engine, while also providing
piping isolation for on-engine purging.
Purging and
venting valves
The iGPR is installed with multiple valves that isolate inert gas and vent lines
from the main fuel gas piping. In the event that a gas trip is initiated by the safety
system, these valves are automatically opened. Inert gas is then supplied to the
iGPR, and the engine’s fuel gas system is purged of gas. Manual activation of the
valves is available for fuel gas system maintenance.
Flow meter
Fuel gas consumption is measured by a Coriolis flow meter.
Gas filter
Fuel gas supply to the iGPR is filtered using an integrated gas filter.
Control system
The control system is based on the same hardware and reliable components as
used on the engine itself. The complete iGPR control is allocated in the iGPR
control box. Based on signals from the control system logic, the solenoids control
the pneumatically actuated valves. A control panel is mounted on the iGPR con
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trol box, where the status of all valves and readings from sensors are displayed.
