10
4.3.3.
Mounting by means of a header frame
The water cover can also be made out of two parts: a
rectangular header frame (
item 2 of fig. 10a
) with a
flat cover (
item 1 of fig. 10a
).
The rectangular header frame is directly welded into
the top plate of the sea chest (according to the
welding instructions of section 4.2). So in that case
there is no (separate) mounting frame.
After the header frame is welded in the top plate, the
tube bundle (
item 3 of fig. 10a
) is installed from below
and the header from above.
Fig. 10a shows an Allen head screw (socket head cap
screw) which remains in place when the cover is
removed. Fig. 10b shows the standard bolts.
Note that the Allen head screws, like the collar
bolts, must ensure a watertight sealing when
the water cover is removed.
Assembly and installation of the tube bundle:
1)
Take the tube bundle, the gasket and the
mounting materials out of the wooden case and
inspect and clean the parts according to the
instructions of section 4.3.1.
2)
Position the gasket that is used between the
header frame and the tube bundle on top of the
tube sheet. Make sure the gasket and the gasket
faces are clean.
Do not use sealant, grease, glue or any other
agent when installing the SBR gasket.
3)
Lift the tube bundle (refer to fig. 2) until just
below the header frame, but leaving sufficient
space to remove the eyebolts. (See "1" of fig. 10c.)
4)
Then take it over from the eyebolts using 4 long
threaded rods with nuts. Insert 4 M12 treaded
rods through the corners of the header frame and
tighten them in the corresponding threaded holes
of the tube sheet.
Secure the tube bundle by putting nuts on the
threaded rods.
5)
Now the eyebolts and the lifting gear can be
removed.
6)
Pull the tube bundle against the header frame.
This can be done by fastening the 4 nuts evenly,
or by putting 4 forged eyenuts (M12) on the
threaded rods and lifting the bundle with a lifting
devise.
Keep tightening the nuts during lifting to secure
the position of the tube bundle.
7)
Finally, fasten the tube bundle with the Allen head
screws, see fig.10a.
The thread rods and the eyebolts and nuts are not part
of the scope of supply from Duramax Marine®. The
required length of the threaded rods is 0.5 to 1.0 m
(depending on the size of the box cooler and the way
the tube bundle is lifted).
Figure 10a. Mounting arrangement with header frame (2),
flat cover (1), tube sheet (3) and Allen head screw.
Figure 10b. Mounting arrangement with header frame, flat
cover and a standard bolt.
Figure 10c. Lifting the tube bundle towards the header
frame in the top plate.
