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Q1. A. Describe an automatic self de-sludging centrifuge suitable for dealing with fuel of density upto 1010 kg/m3 at 150C;

B. Explain how the centrifuge described in Q4 (a) is able to remove water from a fuel which has a density that is higher than that of water and state factors that may assist the operation.

C. As Second Engineer, write down the start-up procedure for the centrifuge described in Q1 (A) for the benefit of your staff;

D. State how is the problem of catalytic fines in fuel oil may be dealt with.

Q2.A. Explain how analysis of used lubricating oil can be used as a “health-monitoring” tool for diesel engines.

B. Describe how vibration measurement can be used with a main engine turbo-charger:

i. For fault analysis;

ii. For condition monitoring with respect to maintenance;

iii. As a substitute to opening up machinery for survey.

Q3. Sketch and describe a boiler water level controller of the float operated type. State the reasons for having this mechanism on the boiler and using this controller and boiler for analogy explain the following terms.

A. Detecting element

B. Servo motor

C. Desired Value

Q4. With reference to hydraulic steering gears, sketch and describe each of the following: (A)Single failure concept;

(B)100 Percent redundancy.

Q5. A. State why fixed pitch propellers have a poor efficiency when going astern.

B. With reference to controllable pitch propellers state:

i. Why is it preferable that the main servomotor be housed in the propeller hub rather than in the shafting forward of the propeller shaft?

ii. What regular maintenance and checks should be carried out to ensure maximum reliability of the gear at all times?

Q6. With regards to main transmission shaft flange coupling arrangements:

A. Sketch a hollow type coupling bolt and the hydraulic head/nut and loading rod which are used to fit it.

B. Describe how the bolt is fitted.

C. State the advantage of the hollow coupling bolt as compared to the traditional type of coupling bolt.

Q7. A. Explain why centrifugal pumps cannot handle air or vapours to effect priming yet turbo- blowers operating on the same principle can.

B. If a vessel is fully laden, how may it be ascertained that the fire pump priming arrangements would operate satisfactorily in the ballast condition.

C. Explain a suitable method of priming suitable for a centrifugal pump.

Q8. (a) Explain Creep, Brinelling , Fretting and Fretting corrosion.

(b) Where and why does creep, Brinelling, Fretting and Fretting corrosion occur in a ship propulsion system?

Q9.  Reverse osmosis is one of the alternative method for shipboard production of drinking water.

(a)  Describe using simple diagrams if necessary,  the principle of reverse osmosis.

(b) (i) Sketch a line diagram showing a single pass system for producing fresh water from sea water

(ii) Describe such a system.