4
030419.04
Waterlock NLP
1
Introduction
The Vetus exhaust system components are especially suitable for use
in
water-injected
exhaust systems.
The maximum temperature when in continuous use depends on the
material used to construct the waterlock.
The material used can be recognised by its colour.
Type
Colour
maximum continuous operat-
ing temperature
NLPxx(S)
Gray
70˚C (158˚F)
NLPxx(S)HD
Black
250˚C (482˚F)
NLPxx(S)WHD
White
• Fit a temperature alarm to warn of excessively hot exhaust
system temperature.
• If the quantity of injected coolant water is reduced to in
order to lower back-pressure in the exhaust system, check
that there is still sufficient water injected when the engine
is ticking-over. This will prevent excess temperatures in the
exhaust system.
• Excess temperature can also be the consequence of insuffi-
cient mixing of coolant water with the exhaust gasses.
In general, good mixing is obtained by a virtually vertically
installed exhaust injection bend.
Poor mixing can also occur with an engine on tick-over; es-
pecially when the coolant water injection bend is installed
virtually horizontally.
If necessary, take action. For example; by fitting a water vor-
tex or a water splitter in the exhaust pipe, to improve the
mixing of coolant water with the exhaust gasses.
With water-injected exhaust systems, fit a hose of suitable quality.
This hose must be reinforced, resistant to exhaust gasses, high tem-
peratures (100 degrees C, 212 degrees F) and oil. Easy flexibility is
essential for installation, while the hose must not collapse when
heated.
Vetus exhaust hose fulfils all the above requirements.
W
arning
If water enters the engine from the waterlock into the exhaust
system (for example: under sail when the ship rolls or pitches
heavily) this will lead to irreparable damage to the engine.
Too much water in the waterlock can effect engine starting;
drain off this water first. Too much water in the waterlock can
be also caused by repeated starting attempts while the engine
refuses to start.
2
Installation
2.1 Installing waterlock NLP
Instal the waterlock as vertical as possible.
The waterlock ‘IN’-connection must always remain below the level
of the exhaust injection bend! Position the waterlock
‘back-to-front’
alongside the engine when there is insufficient space behind the en-
gine.
When in use, the waterlock will contain water. As a result, its weight
will increase considerably. The waterlock must therefore be mounted
on the deck or a wall, as is indicated in the diagrams.
2.2 Installing the transom exhaust connection
Fit the transom exhaust connection at such a position that with the
ship fully laden, the outlet is still at least 5 cm (2”) above the water-
line.
2.3 Exhaust pipe
In order to ensure the proper drainage of the coolant water injected
into the exhaust pipe, the pipe must be installed with a slope down-
ward over its whole length from the water injection point to the wa-
terlock.
During operation, the exhaust pipe will contain water. This will in-
crease its weight considerably, so support the exhaust pipe properly.
The exhaust pipe from waterlock to transom connection must be in-
stalled in such a way that:
- The highest point in the exhaust pipe should not be more than
150 cm (60”) above the underside of the waterlock.
- The length of the section between the waterlock and the highest
point, should not exceed 300 cm (120”).
