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MAN B&W 16.02
Dual Fuel Control System
General
In addition to the above a special dual fuel control
system <strong>is</strong> being developed to control the dual�fuel
operation when the engine <strong>is</strong> operating on compressed
gaseous fuels. See Fig. 16.02.01. The
control system <strong>is</strong> the glue that ties all the dual fuel
parts in the internal and the external system together
and makes the engine run in gas mode.
As mentioned earlier the system <strong>is</strong> designed as an
add�on system to the original ME control system.
The consequence <strong>is</strong> that the Bridge panel, the
Main Operating Panel (MOP) & the Local Operating
Panel (LOP) will stay unchanged. All operations
in gas mode are therefore performed from
the engine room alone.
When the dual fuel control system <strong>is</strong> running the
ex<strong>is</strong>ting ME control and alarm system will stay in
full operation.
Mainly for hardware reasons the control of the
dual fuel operation <strong>is</strong> divided into:
• Plant control
• Fuel control
• Safety Control
Plant control
The task of the plant control <strong>is</strong> to handle the
switch between the two stable states:
• Gas Safe Condition State ( HFO only)
• Dual�Fuel State
The plant control can operate all the fuel gas
equipment shown in Fig. 1.06.01. For the plant
control to operate it <strong>is</strong> required that the Safety
Control allows it to work otherw<strong>is</strong>e the Safety
Control will overrule and return to a Gas Safe
Condition.
Fuel control
The task of the fuel control <strong>is</strong> to determine the fuel
gas index and the pilot oil index when running in
the three different modes shown in Fig. 16.01.01.
Safety control
The task of the safety system <strong>is</strong> to monitor:
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• all fuel gas equipment and the related auxiliary
equipment
• the ex<strong>is</strong>ting shut down signal from the ME safety
system.
• the cylinder condition for being in a condition
allowing fuel gas to be injected.
If one of the above mentioned failures <strong>is</strong> detected
then the Safety Control releases the fuel gas Shut
Down sequence below:
The Shut down valve V4 and the master valve V1
will be closed. The ELGI valves will be d<strong>is</strong>abled.
The fuel gas will be blow out by opening valve V2
and finally the gas pipe system will be purged with
inert gas. See also Fig. 7.00.01.
Architecture of the Dual Fuel Control
System
Dual Fuel running <strong>is</strong> not essential for the manoeuvrability
of the ship as the engine will continue
to run on fuel oil if an unintended fuel gas stop
occurs. The two fundamental architectural and
design demands of the fuel gas Equipment are, in
order of priority:
• Safety to personnel must be at least on the
same level as for a conventional diesel engine
• A fault in the Dual Fuel equipment must cause
stop of gas operation and change over to Gas
Safe Condition.
Which to some extent complement each other.
The Dual Fuel Control System <strong>is</strong> designed to ‘fail
to safe condition’. See Fig. 16.02.02. All failures
detected during fuel gas running and failures of
the control system itself will result in a fuel gas
Stop / Shut Down and change over to fuel operation.
Followed by blow out and purging of high
pressure fuel gas pipes which releases all gas
from the entire gas supply system.
MAN B&W ME/ME-C/ME-B/-GI engines 198 50 61-9.1
MAN Diesel