 | |
| Illustration 1 | g00753032 |
(1) Mixer housing (2) Expansion tank (3) Orifice (4) Orifice (5) Water temperature regulator (6) Manual bypass valve (7) Orifice (8) Sea water (9) Heat exchanger (10) Orifice (11) Water temperature regulator (12) Turbocharger (13) Cylinder block (14) Aftercooler (15) Jacket water heater (16) Jacket water heater's pump (17) Jacket water pump (18) Aftercooler water pump | |
The cooling system of this 3608 is a combined circuit cooling system. The combined circuit cooling system operates with two attached pumps that are driven by the engine. The jacket water pump supplies coolant to the cylinder heads, the cylinder block and the turbocharger. The aftercooler water pump supplies coolant to the aftercooler. The water temperature regulators that are located in the water temperature regulator housing regulate the jacket water coolant temperature to 90 °C (194 °F). There is a manually operated valve that is used to bypass the water temperature regulators if the water temperature regulators fail in the closed position.
There is a separate water temperature regulator that controls the temperature of the water to the aftercooler pump at 32 °C (90 °F). This water temperature regulator controls the amount of water that is sent to the plate type heat exchanger. The plate type heat exchanger is cooled with sea water. After the water from the aftercooler circuit exits the aftercooler, the water mixes with the jacket water from the engine in order to provide the 90 °C (194 °F) water back to the engine. The plate type heat exchanger is designed with a 6 °C (43 °F) approach. If the ship is in 32 °C (90 °F) sea water, the system will deliver 38 °C (100 °F) water to the aftercooler. The engine will still meet the IMO emission requirements with 38 °C (100 °F) water to the aftercooler.
The engine uses a shunt design cooling system that has a remote mounted expansion tank. The remote mounted expansion tank functions as a head tank. The remote mounted expansion tank has a capacity of 189 L (50 US gal). There is a 12.7 mm (0.5 inch) vent line from the deaerator. The deaerator is mounted on the top of the mixer housing. This deaerator will separate entrapped air from the coolant. The entrapped air is then vented to the remote mounted expansion tank which vents the air to the atmosphere. There is a 50.8 mm (2 inch) return line from the remote mounted expansion tank to the return line from the heat exchanger to the aftercooler pump's suction line. This return line will act as a stand pipe because the flow will be small.
The system is also equipped with a jacket water heater and the system is equipped with a pump for the heater. The pump circulates water from the cylinder block, through the heater, and then back to the cylinder block. This keeps the engine warm during stopped conditions.