6
For a high temperature (HT) circuit, provide
6 dm
2
of
inlet slots per 100 kW
heat rejection.
For a low temperature (LT) circuit, provide
9 dm
2
of
inlet slots per 100 kW
heat rejection.
The area of the
outlet slots
should be
80%
of the inlet
slots.
Figure 4. Examples of inlet slots in a hatch (to be used
as inspection opening/man hole).
Figure 5. Maintain a closed area between the inlet and
outlet slots of at least 25% of the hull section.
9.
In case these slots are not possible, make as many
openings as possible. Position (sea) water inlet slots as
low as possible and outlet slots as high as possible.
Assure a closed sea chest surface between the inlet
and outlet slots of at least 25% of the total tube length
(see fig. 5).
When in doubt contact Duramax Marine® for advice
and send a drawing of the sea chest.
10.
All materials for the sea chest, including the top plate
and the (supplied) mounting frame, should have at
least equal thickness as the rest of the ship's plating.
11.
The tube bundle is made of copper alloys. These
metals are more noble than the carbon steel sea
chest. Without proper protection, this may cause
severe galvanic corrosion of the sea chest due to
galvanic currents between the tube bundle and the
sea chest, where the (sea) water serves as an
electrolyte.
To protect the sea chest from galvanic corrosion
all
metal areas of the sea chest shall be well preserved.
Furthermore, it is highly recommended to
install
sacrificial anodes.
12.
Make sure that the space above the box cooler allows
for sufficient access to carry out installation,
inspection, cleaning and maintenance (see also section
6).
Top mounted box coolers also require sufficient space
for installation and retraction of the tube bundle.
4.2.
WELDING THE MOUNTING FRAME IN
POSITION
After welding the mounting frame is part of the
ship's hull. All reinforcements, stiffeners, hull
material and thicknesses are to be defined by the
yard.
All welding shall be carried out according to the
applicable requirements of the Classification
Society's Rules.
Recommended is for T-‐joints to use double bevel T-‐
butt welds (see fig. 9 and 10) to minimize distortion.
Avoid damage to the box cooler. Do not weld on or
near the mounting frame when the box cooler is
installed.
If a mounting frame is not part of the order, use the bolt
pattern of the water cover as a drilling template.
1)
Move the wooden crate with the box cooler and all
related parts to area where the sea chest is located.
2)
Take the carbon steel mounting frame out of the
wooden case (note that alternative configurations
exist, see section 4.3.1, 4.3.2 and 4.3.3).
