Fig. 32: Procedure Wet Cleaning Of Turbine And Nozzle Ring - ABB HT608016 Operation Manual

Operation Manual / A170-M.. - A175-M..
7 Periodic maintenance / 7.5 Cleaning turbine and nozzle ring
Procedure
Fig. 32: Procedure Wet cleaning of turbine and nozzle ring
The prerequisites and the operating state must be fulfilled prior to cleaning.
Make sure that the water supply (01) is connected, switched on and safeguarded.
u
Switch the 3-way valve (04) from scavenging air mode to water supply.
u
Set the necessary water quantity on the flowmeter (08) according to the table Cleaning
u
parameters (see Table 19: Cleaning parameters Wet cleaning of turbine and nozzle ring
→69).
Shut off the water supply again by switching the 3-way valve (04) to scavenging air mode
u
after the prescribed injection time has elapsed.
The injection process is complete.
After cleaning, continue to operate the engine for at least 10 minutes without any load
u
change.
It is necessary to have the corresponding water pipe pressure in order to achieve the correct
water flow rate (see Table 19: Cleaning parameters Wet cleaning of turbine and nozzle ring
→69). If there is insufficient water pressure, the water flow rate specified in the table will
not be achieved. A reduced cleaning effect can be expected in this case.
Repetition of wet cleaning
The repeating of cleaning cycles one immediately after the other must be avoided as this
can lead to excessive mechanical stress, hence reducing the operating life of the compon-
ents.
If the cleaning process is ineffective, the duration can be extended. If the injection time is ex-
tended, it is important to ensure that no impermissible volume of water collects in the gas
outlet casing. A drainage system should be installed for the gas outlet casing and opened
during cleaning. If there is no drainage system, the amount of water injected can be mon-
itored with a flowmeter in the water supply. The permitted amount of water must be de-
termined with the help of an ABB Turbocharging Service Station.
To be observed during cleaning
¡
The action of the cleaning water on the peripheral units (such as boiler) must be clarified
by the operator.
¡
The exhaust gas temperature downstream of the turbocharger drops drastically during
cleaning (typical turbocharger outlet temperatures during cleaning: 60...180°C).
© Copyright 2021 ABB. All rights reserved. HZTL4033_EN Rev.H July 2021