Iveco Marine Diesel Engines, Руководство по установке

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Anyway consider the following general indications:
■
The air inlets, to be dimensioned with the right margin, shall be structured to prevent the sea water
passage, accidental or not, which is particularly dangerous when present in the air of supercharged
engines, as the turbochargers would rapidly be damaged, with the related consequences;
■
The ducts and the pipes shall put up the least resistance to the air flow. The curves must be wide
and their number the lowest possible. Avoid localised narrowing.
■
The global pressure drop in air ducts shall not exceed 0.5 - 1 mbar of the air overall intake for ven-
tilation and combustion;
■
Prevent accidental clogging of air ducts to the engine room (air inlets, pipes, etc.) which would lead
to excessive depression in the engine room with the obvious consequences for the engines.
■
The ventilation system adopted must be previously checked on the prototype during specific sea
tests, to verify efficiency and carry out the necessary changes and improvements.The tests shall be
carried out with the boat at the maximum speed and the engines at full load and maximum rpm
for a sufficiently long time, in order to check that the environmental conditions got stabilised.
5.3 AIR FILTERS
The environment where the marine engine operates does not usually have a high level of dust
(< 2 mg/m
3 ).
In most cases simplified filters usually fitted on IVECO engines are sufficient.
In particular cases where the environment can be dusty, as on work boats for the transport of dusty
materials, it is necessary to apply, separated from the engine, more efficient air filters usually adopted
on industrial applications.
In this case the application must consider the following:
■
The maximum depression allowed by the engine suction (filter total plus pipes) shall not exceed 35
mbar with the new filter and 65 mbar with the dirty filter.These limits are valid both for aspirated
and supercharged engines;
■
The connection pipe between the engine and the filter, with the correct diameter complying with
the above mentioned needs, can consist of a metal pipe fitted with rubber sleeve at the end or a
rubber hose with steel inserts having the right dustproof ends;
■
Anyway all the joints must be dustproof; it is suggested to use screw steel clamps tightening the
rubber sleeve on the ends of the pipe to be connected;
■
Ensure the maximum cleaning of the pipe inside (no metal scraps, welding remains or other mate-
rial which can be sucked by the engine and therefore damage it);
■
It is advisable to apply the right pressure outlet with the suitable clogging sensor downstream of
the filter.
MARCH 2004 AIR SUPPLY
5.62
MARINE ENGINES INSTALLATION