Chapter 6 Cooling Water System
4. Heat Exchanger
,
4LHA Seri
4-2
Specifications
of
heat
exchanger
Radiation
area
m
2
(in.
2
)
0.593 (919)
Fresh
water
discharged
volume £/hr(in.
3
/hr)
8.000 (488.160)
Sea
water
discharged
volume
^/hr(in.
3
/hr)
6.000 (366.119)
Fresh
water flow
speed
in
cooling
pipe
m/s
(ft/s)
1.5 (4.9)
Sea
water flow
speed
in
cooling
tube
m/s
(ft/s)
2.17 (7.12)
4-3 Disassembly and
reassembly
of the
heat
exchanger
(1) Remove the covers on both sides and take out the
cool-
ing pipe and O-ring(s).
NOTE: Replace the O-ring(s) when you have removed the
cooling pipe.
(2) Remove the filler assembly.
4-4
Heat
exchanger
inspection
(1) Cooling pipe inspection
1) Inspect the inside of the tubes for rust or scale build-
up from sea water, and clean
with
a wire brush if
necessary.
NOTE: Disassemble and wash when the cooling water
temperature reaches 85
0
C.
2) Check the joints at both ends of the tubes for
looseness
or damage, and repair if loose. Replace if
damaged
or corroded.
3) Check tubes and replace if leaking.
4)
Clean
any scale or rust off the outside of the tubes.
(2) Heat exchanger body inspection
1) Check heat exchanger body and side cover for
dirt
and
corrosion.
Replace if
excessively
corroded, or
cracked.
2) Inspect sea water and fresh water inlets and outlets,
retighten any joints as necessary and clean the insides
of the pipes.
3) Check the exchaust gas intake flange and line, and
replace
if corroded or cracked.
6-11