MAN B&W S65ME-C8.2-GI-TII, Project Manual

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MAN B&W 16.02
Page 1 of 6
MAN Diesel MAN B&W ME-GI engines 198 89 31-2.1
In addition to the ME-ECS, a special system is
installed to control the gas supply and to moni-
tor safety issues when the engine is operating on
compressed gaseous fuels. See Fig. 16.02.01.
The GI extension is the glue that ties all the dual
fuel parts in the internal and the external system
together.
As mentioned, the GI extension is designed as an
addon to the standard ME control system. There-
fore, the Bridge panel, the Main Operating Panel
(MOP) and the Local Operating Panel (LOP) is
equipped with a gas-running indication lamp. All
operations in gas mode are performed from the
engine room alone, while the operation from the
bridge is exactly the same whether in gas or fuel
oil mode.
Gas control
Gas control consists of three parts:
• Dual fuel injection control
• Gas plant control
• Gas safety control.
Dual fuel injection control is additional functional-
ity added to the ECUs and CCUs of the ME-ECS,
while gas plant control and safety control are
handled by additional units: the GPCU (Gas Plant
Control Unit) and GACU (Gas Auxiliary Control
Unit), respectively GPSU (Gas Plant Safety Unit)
and GCSUs (Gas Cylinder Safety Units).
Gas plant control
Plant control has the functions of:
A – Controlling the supply of gas from the FGSS
(Fuel Gas Supply System) to the engine in a safe
way.
B – Close down the supply of gas to the engine
after end of gas operation.
Function A includes:
• purge the gas pipes and gas volumes for atmos-
pheric air before open the gas
• start the double-pipe ventilation system and
turn on double-pipe leakage detection
• apply gas to engine in steps, while checking for
leakage and correct function of valves, while the
gas pressure is built up
• start the sealing oil system, when gas is entering
the cylinder cover.
Function B includes:
• close the gas block valves
• release the gas pressure
• stop the sealing oil system
• start purging the gas pipes and volumes
• stop the double-pipe ventilation.
Furthermore, the task of the plant control is to
handle the switch between the two stable states:
• Fuel oil mode (HFO only)
• Gas mode.
The gas plant control can operate all the fuel gas
equipment. For the plant control to operate, it is
required that the Safety Control allows it to work,
otherwise the Safety Control will overrule and re-
turn to a Gas Safe Condition.
Dual fuel injection control
The task of the fuel control is to determine the fuel
gas index and the pilot oil index when running in
the different modes.
Engine Control System – GI Extension