WÄRTSILÄ VASA 6L32, Instruction Manual

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18.5.4 Cleaning of oil side
Fouling of the oil side is normally insignificant. On the other hand,
possible fouling will influence the cooler efficiency very strongly.
Due to the design, the tube stack cannot be cleaned mechani-
cally on the outside. Slight fouling can be removed by blowing
steam through the tube stack.
If the amount of dirt is considerable, use chemical cleaning
solutions available on the market:
Alkaline degreasing agents:
Suitable for normal degreasing, however, not effective for heavy
greases, sludge and oil coke. Requires high temperature. Always
pour degreasing agent slowly into hot water, never the contrary.
Rinse carefully with water after treatment.
Hydrocarbon solvents:
Include the whole range from light petroleum solutions to chlo-
rinated hydrocarbons, e.g. thrichlorethylene. These products
should be handled with care as they are often extremely volatile,
toxic and/or narcotic.
Solvent emulsions:
Heavy fouling, e.g. oil coke, can often be dissolved only by using
these solutions. Several brands are available on the market.
Follow the manufacturer’s instructions to achieve the best
results.
18.5.5 Cleaning of water side
The cleaning should be carried out so that it does not damage the
natural protective layer on the tubes. Use nylon brushes, metallic
brushes can damage the natural protective layer.
Remove loose sludge and deposits with brush 4V84F06. Rinse
with water.
If the deposit in the tubes is hard, e.g. calcium carbonate, it can
be removed chemically by using commercial agents. After this
treatment the tubes should be rinsed and, if necessary, treated
with a solution neutralizing the residual washing agents. Other-
wise, follow the manufacturer’s instructions.
18 Lubricating Oil System 32-200052
18 - 10 WÄRTSILÄ 32