Man L23/30DF, Project Manual

Page: 225 / 392

Description
During operation the compressor will gradually be
fouled due to the presence of oil mist and dust in
the inlet air.
The fouling reduces the efficiency of the turbo-
charger which will result in reduced engine perform-
ance.
Therefore manual cleaning of the compressor com-
ponents is necessary in connection with overhauls.
This situation requires dismantling of the turbo-
charger.
However, regular cleaning by injecting water into
the compressor during normal operation of the
engine has proved to reduce the fouling rate to
such an extent that good performance can be
maintained in the period between major overhauls
of the turbocharger.
The cleaning effect of injecting pure fresh water is
mainly based upon the mechanical effect arising,
when the water droplets impinge the deposit layer
on the compressor components.
The water is injected in a measured amount and
within a measured period of time by means of the
water washing equipment.
The water washing equipment, see fig 1, comprises
two major parts. The transportable container (6)
including a hand valve with handle (5) and a plug-in
coupling (4) at the end of a lance.
Installed on the engine there is the injection tube (1),
connected to a pipe (2) and a snap coupling (3).
The cleaning procedure is:
1) Fill the container (6) with a measured amount of
fresh water. Blow air into the container by
means of a blow gun, until the prescribed
operation pressure is reached.
2) Connect the plug-in coupling of the lance to
the snap coupling on the pipe, and depress the
handle on the hand valve.
3) The water is then injected into the compressor.
The washing procedure is executed with the engine
running at normal operating temperature and with
the engine load as high as possible, i.e. at a high
compressor speed.
The frequency of water washing should be matched
to the degree of fouling in each individual plant.
1 Injection tube 2 Pipe
3 Snap coupling 4 Plug-in coupling
5 Hand valve with handle 6 Container
7 Charge air line
Figure 1: Water washing equipment.
MAN Diesel & Turbo
1639499-6.0
Page 1 (1)
Water washing of turbocharger - compressor
B 15 05 1
L23/30DF, L28/32S, L27/38S, L23/30S, L21/31S, L28/32DF, V28/32S, L21/31,
L23/30H, L27/38, L28/32H
2016.01.05