Examination of Marine Engineer Officer s1

95SCS-4 Sr. No. 9

EXAMINATION OF MARINE ENGINEER OFFICER Function: Controlling the Operation of The Ship & Care for Persons on Board at Operational Level SHIP CONSTRUCTION AND STABILITY

M.E.O. Class IV (Time allowed - 3hours) India (2003) Afternoon Paper Total Marks 100

NB : (1) Answer SIX Questions : SECTION -1 :- Answer atleast TWO Questions SECTION -2 :- Answer atleast TWO Questions (2) All Questions carry equal marks (3) Neatness in handwriting and clarity in expression carries weightage (4) Illustration of an Answer with clear sketches / diagrams carries weightage.

SECTION - 1

1. State where the following types of corrosion may occur, and the materials commonly involved in each case. (i) Fretting corrosion; (ii) Impingement corrosion; (iii) Galvanic corrosion; (iv) Crevice corrosion;

2. Define the following stating how they affect the ship structure and what component parts of the ship structure help to resist the effect- (a) Racking (b) Water pressure effect (c) Vibration from engine and propellers.

3. (a) Sketch in detail a bearing designed to transfer the full weight of the rudder and its stock to the ships structure . (b) Explain why the thrust faces are so contoured.

4. With regard to the carriage of crude oil and its associated products: (a) (i) State the dangers involved. (ii) State what publications give guidance on safety. (b) Sketch and describe the operation of an explosimeter suitable for testing pump rooms or tanks. (c) Define the terms lower and upper flammable limits illustrating your answer by means of a rough sketch of a hydrocarbon vapour oxygen graph. 5. Angular motion about the vertical axis of a vessel is known as ______. (a) yaw (b) surge (c) sway (d) roll Given a reasoned explanation to your choice of answer and why the other alternative were not considered.

SECTION – 2

6. The ½ girths of a ship 90 m long are as follows. 2.1, 6.6, 9.3, 10.5, 11.0, 11.0, 11.0, 9.9, 7.5, 3.9 and 0 m respectively. The wetted surface area of the appendages is 30 m2 and ½ % is to be added for longitudinal curvature. Calculate the wetted surface area of the ship.

7. A ship displaces 12000 tonne, its centre of gravity is 6.50 m above the keel and its centre of buoyancy is 3.60 m above the keel. If the second moment of area of the waterplane above the centreline is 42.5 x 103 m4 find the metacentric height.

8. The residuary resistance of a one-twentieth scale model of a ship in seawater is 36 N when towed at 3 knots. Calculate the residuary resistance of the ship at its corresponding speed and the power required to overcome residuary resistance at this speed.

9. The waterplane area of a ship at 8.40 m draught is 1670 m2. The areas of successive waterplanes at 1.40 m intervals below this are 1600, 1540, 1420, 1270, 1080 and 690 m2 respectively. Calculate the displacement in fresh water at 8.40 m draught and the draught at which the ship would be in seawater with the same displacement.

10. A bulkhead 12 m wide and 9 m high is secured at the base by an angle bar having 20 mm diameter rivets on a pitch of 80 mm. The bulkhead is loaded on one side only to the top edge with seawater. Calculate the stress in the rivets.

------X------95SCS-4 Sr. No. 9

EXAMINATION OF MARINE ENGINEER OFFICER Function: Controlling the Operation of The Ship & Care for Persons on Board at Operational Level SHIP CONSTRUCTION AND STABILITY

M.E.O. Class IV (Time allowed - 3hours) India (2003) Afternoon Paper Total Marks 100

NB : (1) Answer SIX Questions : SECTION -1 :- Answer atleast TWO Questions SECTION -2 :- Answer atleast TWO Questions (2) All Questions carry equal marks (3) Neatness in handwriting and clarity in expression carries weightage (4) Illustration of an Answer with clear sketches / diagrams carries weightage.

Q5. Correct Answer : A