Examination of MEO, EK

78EKM-1 Sr. No. 6

EXAMINATION OF MARINE ENGINEER OFFICER

ENGINEERING KNOWLEDGE

(MOTOR)

CLASS I

(Time allowed – 3 hours)

Motor Candidate

INDIA Afternoon Paper Total Marks 100

N.B. - (1) Attempt SIX questions ONLY.

(2) All questions carry equal marks.

(3) Marks for each part question are shown in brackets.

(4) Neatness in handwriting and clarity in expression carries weightage

1. You have been recently appointed as the Chief Engineer of a vessel which is still being constructed in the shipyard and is in the final stages of delivery. The sea trial reports of the vessel have not been upto excpectations with reference to the owners specification. Submit a technical report on the sea trials explaining how it was deficient in the key areas of power developed and speed achieved. (16)

2. An Indian owner has placed orders for three 500 DWT cargo carriers with an Indian shipyard. The shipyard has proposed to put fire fighting equipment on board the vessel which has two main engines run on heavy oil of 700kW capacity each coupled to a single propeller through a gear box.

(a) List out the fire fighting equipment portable and nonportable which will be required on board.

(b) Under which class of the Indian fire appliances rule 1990 would you place the vessel? (16)

3. Explosions occasionally occur in silencers and exhaust manifolds of main engines upon restarting after an unscheduled stop at sea.

(a) Suggest two possible causes for such explosions. (8)

(b) State how the possibility of such occurrence can be reduced. (8)

4. Explain the meaning of the term 'critical speed range' as applied to diesel engines. (8)

(a) Explain why an engine should not be operated continuously in or near this range. (4)

(b) State how the effect of 'critical speed range' is reduced. (4)

5. State the considerations governing main air receiver capacity.

(a) Give reasons why the internal surfaces of air receivers are frequently coated with clear varnish.(8)

(b) Explain why air receiver drain valves should be overhauled at every available opportunity. (8)

6. Sketch and describe a fully automatic 'Package' boiler. (8)

(a) Identify the safety devices fitted and their function. (4)

(b) Define the advantages of packaged boilers over exhaust gas boilers. (4)

7. The amount of wear on a split precision main bearing can be accurately determined by comparing the data from a previous reading to the present readings taken with one of the following: (16)

(a) Dial indicating outside caliper (b) Telescoping gauge

State why bearing wear cannot be measured accurately with a crankshaft deflection gauge

8. In comparison to exhaust valves, intake valves of diesel engines may be fabricated from low-alloy steels because of one or a combination of the following : (16)

(a) The beveled edges of the intake valves provide for self-centering during seating

(b) Intake valves utilize stellite-coated valve seat inserts which reduce wear

(d) Intake valves are less affected to the corrosive action of exhaust gases

Support your answer with adequate reasons.

9. In a bypass type filtering system for a medium or high speed diesel engine, the lube oil bypassing the filter performs one of the following functions. (16)

(a) Returns directly to the suction side of the pump

(b) Returns directly to the sump

(d) Flows through a second-stage strainer, reheater, and returns to the sump

Give the correct answer and explain why the other functions are impracticable.

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