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194 Deck machinery and hull equipment
and communications. The diesel engine has its own supply system,
usually of light diesel oil for easy starting. Batteries, compressed air or
an hydraulic accumulator may be used for starting the machine. Small
machines may be air cooled but larger units are arranged usually for
water cooling with an air cooled radiator as heat exchanger in the
system. A small switchboard is located in the same compartment to
connect the supply to the various emergency services (see Chapter 14).
Modern systems are arranged to start up the emergency generator
automatically when the main power supply fails. The system should be
checked regularly and operated to ensure its availability if required. Fuel
tanks should be kept full, ample cooling water should be in the radiator
cooling system, and the starting equipment should be functional.
Batteries of course, should be fully charged or air receivers full.
The emergency fire pump is arranged to supply the ship's fire main
when the machinery space pump is not available. One possible
arrangement, as used on large tankers, is shown diagrammatically in
Figure 10.11. A diesel engine with its own fuel supply system, starting
Diesel Engine
Discharge to Fire Main Hyd Oil Pump
Discharge to
Main Fire
Pump Suction
Submersible
Hyd Oil
Booster Motor Driven Hyd Oil Supply
Sea Suction Pump Pump and Return
Figure 10.11 Emergency fire pump