WÄRTSILÄ Vasa R22, Инструкция по эксплуатации

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at no load for more than 3 minutes before loading, as well as idling
more than 3 minutes before stopping is unnecessary and should
be avoided.
02.1.6 General advice
To avoid stability and incompatibility problems (precipitation of
heavy components in the fuel), avoid if possible blending of fuels
from different bunker stations, unless the fuels are known to be
compatible.
If stability and compatibility problems occur, never add distil-
late fuel, as this will probably increase precipitation. A fuel
additive with a highly powerful dispersing characteristics can be
of help until a new fuel delivery takes place.
The characteristics of heavy fuels blended from residuals from
modern refinery processes like catalytic cracking and visbreaking
may approach at least some of the maximum limits of fuel
characteristics given in the table in chapter 02, section 02.1.3.
Compared
with “traditional” heavy fuels blended from straight
run residuals the “modern” heavy fuels may have reduced ignition
and combustion quality.
Fuels blended from catalytic cracking residuals may contain
very abrasive catalytic fines (silicon and aluminium oxides)
which, if allowed to enter the injection system, may wear down
injection pumps and nozzles in a few hours.
Some of the difficulties that may occur when operating on heavy
fuels blended from cracked residuals can be avoided by:
•
sufficient separating capacity. The best and most distur-
bance-free results are obtained with purifier and clarifier in
series. Alternatively the main and stand-by separators may
be run in parallel, but this makes heavier demands on correct
gravity disc choice and constant flow and temperature con-
trol to achieve optimum results. The flow rate through the
centrifuges should not exceed the maximum fuel consump-
tion by more than 10 %,
•
sufficient heating capacity to keep centrifuging and injection
temperatures at recommended levels. It is important that
the temperature fluctuations are as low as possible (
±
2°C
before centrifuge) when centrifuging high viscosity fuels
with densities approaching 0.991 g/ml at 15°C,
•
sufficient preheating of the engine and the fuel systems
before starting the engine,
•
keeping fuel injection equipment and the inverse cooling
system in good condition.
22-9601 Fuel, Lubricating Oil, Cooling Water 02
VASA 22 02 - 9