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Q1. i) Sketch and describe using a Fuel oil treatment before injection. (10)

ii) What is the purpose of centrifuging fuel and how gravity disc is selected? (3)

iii) Why homogenisers and fine filters are used downstream? (3)

Q2. i) Explain using a simple line diagram difference between lubricating oil systems dealing with cylinder lubrication vis-à-vis crankcase lubrication. (7)

ii) State the properties of oil essential in each of these cases. (4)

iii) What is synthetic oil? How it is different from Mineral oil? Where is it used? (5)

Q3. Sketch and describe a ‘Four ram electro hydraulic steering system’, showing pump isolating valves, relief valves and bypass valves. (10)

ii) Indicate & explain valve position for one pump isolation and one unit isolation. (6)

Q2. i) Sketch and describe the modern purification system using ‘ALCAP’ concept for purifying fuel specific gravity about 0.991. (8)

ii) Explain how ‘ALCAP’ separator operates as clarifier & how is the water drained off? (4)

iii) What is ‘paring disc’? How does it function? (4)

Q5. i) Explain with reasons, as to why ‘boiler water testing’ is carried out on board. (6)

ii) Explain procedure for collecting boiler water sample? State precautions? (4)

iii) Mention with procedure and recommended values for the tests which need to be carried on boiler water as a routine. (6)

Q6. i) Explain the term ‘Volumetric efficiency’ in respect of air compressors. (3)

ii) State reasons for drop in ‘Volumetric efficiency’ and how same can be restored? (7)

iii) Explain the purpose of ‘unloader’. Name the methods used for unloading, for ‘starting’ and ‘stopping’ when on automatic operation. (6)

Q1) (a) Using a line diagram, show the arrangement of ‘emergency bilge suction’ for a general cargo ship (8)

(b) State the purpose of ‘bilge injection valve’ and to which pump or pumps it is connected. Give reasons. (4)

(c) State requirements with respect to the dimensions of the bilge injection valve and the main sea suction valve on the sea chest. (4)

Q5. i) Define ‘centrifugal pump’ and where it is used on ships? Using a simple line diagram show a circuit which include a centrifugal pump. Explain the meaning of ‘suction lift’. (6)

ii) Sketch and describe the construction of a centrifugal pump, labelling its parts. What is a ‘lantern ring’ and why is it fitted? (10)

Q9. i) State the advantages and disadvantages in using centrifugal pump on ship’s duties. (4)

ii) How should a centrifugal pump be operated in order to get best results? (5)

iii) State maintenance schedule for the pump. What parts of the pump are closely checked during surveys? (7)