Iveco Marine Diesel Engines, Installation Handbook

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MARCH 2004 COOLING
8.85
MARINE ENGINES INSTALLATION
Water seacock fitting
It draws sea water overboard for the secondary cooling circuit. It must be properly fitted to filter out
debris before it gets into the suction pipe and to resist seawater aggressions.
Its position in the hull must be carefully chosen to guarantee correct water suction in any navigation
condition. In the case of swift hulls, shallow areas shall be avoided. Use special seacocks, if necessary.
In the case of metallic hulls, the seacock fittings must be made of the same material to avoid galvanic
corrosion. Otherwise, the seacock valve must be electrically insulated.
An appropriate sluice valve should be placed between the seacock fitting and the pump to close the
seacock valve in case of emergency and extended moorings.
Sluice valve installation must guarantee a quick closure, and remote controls may be adopted, if
necessary.
Water filter
It filters the debris that the seacock fails to filter, and which could damage pump impeller or obstruct
the heat exchangers.
Once properly sized, it must be placed in the secondary circuit suction pipes.
In order to protect the circuit efficiently, this filter should be oversized so that it does not get obstruct-
ed too fast or cause excessive pressure drops.
The most important feature to take into account when making a choice is the filter total bored area.
Its size area should be at least five or six times greater than the size of the pump suction pipe section.
Figure 2
Figure 3