MAN B&W 5L28/32H, Руководство пользователя

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08028-0D/H5250/94.08.12
General
Description
The tendency to fouling on the gas side of turbochar-
gers depends on the combustion conditions, which
are a result of the load and the maintenance condi-
tion of the engine as well as the quality of the fuel oil
used.
Fouling of the gas ways will cause higher exhaust
gas temperatures and higher wall temperatures of
the combustion chamber components and will also
lead to a higher fuel consumption rate.
Tests and practical experience have shown that
radial-flow turbines can be successfully cleaned by
the dry cleaning method.
This cleaning method employs cleaning agents con-
sisting of dry solid bodies in the form of granules. A
certain amount of these granules, depending on the
turbocharger size, is, by means of compressed air,
blown into the exhaust gas line before the gas inlet
casing of the turbocharger.
The injection of granulate is done by means of
working air with a pressure of 5-7 bar.
On account of their hardness, particularly suited
blasting agents such as nut-shells, broken or artifici-
ally shaped activated charcoal with a grain size of 1.0
mm to max. 1.5 mm should be used as cleaning
agents.
The solid bodies have a mechanical cleaning effect
which removes any deposits on nozzle vanes and
turbine blades.
Dry cleaning can be executed at full engine load and
does not require any subsequent operating period of
the engine in order to dry out the exhaust system.
Experience has shown, that cleaning of regular
intervals is essential to successful cleaning, as exce-
ssive fouling is thus avoided. Cleaning every second
day during operation is recommended.
The cleaning intervals can be shorter or longer
based on operational experience.
Cleaning System
The cleaning system consists of a cleaning agent
container 1 with a capacity of approx. 0.5 liters and
a removable cover. Furthermore the system con-
sistsof a dosage valve 3, a closing valve 2 and two
snapon connectors.
The position numbers 1 and 3 indicate the system's
"blow-gun". Only one "blow-gun" is used for each
engine plant. The blow-gun is working according to
the ejector principle with pressure air (working air) at
5-7 bar as driven medium. Injection time approx. 2
min. Air consumption approx. 5 Nm
3 /2 min.
92.25
1607599-1.3
Page 1 (3)
Dry Cleaning of Turbocharger - Turbine B 16 01 2
2
1
3
4
5-7 bar
1. Container 4. Working air inlet
2. Closing valve To be connected with ½
3. Dosage valve rubber hose.
Fig. 1. Arrangement of dry cleaning of turbocharger - Turbine.
Granulate consumption
NR 15 R / NR 20 R : 0.2 - 0.3 liters
NR 24 R / NR 26 R : 0.3 - 0.4 liters