Operation Manual / Power2 800-M / 4 Product description
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6.3 Cleaning turbine and nozzle ring during operation
6.3.1 Introduction
Approval by enginebuilder
These instructions for wet cleaning only apply to cleaning with pure water and under the pre-
condition that the enginebuilder approves the process.
The combustion of fuels such as marine diesel oil (MDO) and heavy fuel oil (HFO) in diesel
engines causes contamination of the turbine components of the low and high-pressure stages.
Poor quality fuel in conjunction with a high exhaust gas temperature can lead to very hard
deposits on the nozzle ring, the turbine blades and particularly on the casing walls surrounding
the impellers.
The formation of deposits on the turbine components stems from the following combustion
products:
Soot
Molten ash
Cinders
Incompletely burnt fuel
Sodium vanadyl vanadate
It is advantageous to use fuels with low ash, sulphur, sodium and vanadium contents. The fuel
must also be correctly stored, prepared and handled.
ABB Turbo Systems recommends using fuels with a mass ratio of vanadium to sodium of less
than 3:1 so that the melting temperature of the sodium vanadyl vanadate is as high as possi-
ble.
Consequences of contamination:
Poor turbine efficiency
Elevated exhaust gas temperatures
Higher charging and ignition pressures with increasing speed of the low and high-pressure
stages
Lower engine performance
Increased rotor unbalance
Experience in operation shows that, with periodic cleaning during operation, the interval be-
tween overhauls can be extended. The wet cleaning of a turbine described in the following can
be used for 4-stroke applications with heavy deposits (such as MDO and HFO applications, for
example). Generally, turbine cleaning is not required for the other applications.
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