4. Describe with sketches a centralised cooling system incorporating plate type heat exchangers.
Explain the purpose of this system and how it is achieved.
5. Describe with sketches an axial flow pump.
Explain its principle of operation.
State what important advantage and serious disadvantage it possesses compared to other pumps.
Explain the effects of throttling either the suction or discharge valve.
Class 2
1. Sketch and describe a plate type heat exchanger. State one advantage and one disadvantage of this design compared to the tubular type.
2. Sketch and describe a pump other than the reciprocating or centrifugal type.
Explain how it works.
State with reasons, the duty for which it is most suited.
3. Sketch and describe a centrifugal bilge pump.
Explain the need for a priming pump.
Give one advantage and one disadvantage of the centrifugal pump compared to the direct acting pump for bilge duties.
4. Sketch the construction of all oil-water separator.
Explain how it functions in service.
State the purpose and operation of all alarms or safety devices fitted to the separator.
5. Make a line diagram of a bilge pumping system for a dry cargo ship.
Indicate the type and position of each valve fitted.
In view of the possibility of collision, explain how the integrity of the bilge pumping system is ensured as far as possible.
Class 3
1. Make a diagrammatic sketch of a bilge pumping system itemising the main components.
2. Describe the passage of water through a centrifugal pump.
3. Describe an oil-water separator and state how you would check that it was working satisfactorily.