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Q5. With reference to Container Ships :

(a) Describe the problem of Parametric Roll ;

(b) Explain how this problem is suitably addressed in the design and operation of the vessel.

(c) Describe possible methods for improving the stability of these vessels.

Q2. The Hull of a vessel in way of the purifier room requires extensive welding repairs and as a 2nd Engineer officer you are required to supervise.

a. Suggest a suitable type of welding process.

b. State, With reasons, FOUR common welding defects.

c. State what tests may be carried out for the hull repair before returning the vessel to service.

Q3. A. With reference to the underwater surface of a ship’s hull; i. Describe a hull plate roughness analyser system;

ii. State the significance of the roughness profile and compare the typical roughness values for a new ship and a ship eight years old;

B. Which reference to the application of self-polishing paint in dry dock - i. Describe the plate preparation necessary;

ii. State the defects that may occur in the paint coating if it is not correctly applied.

Q1. (a) What is significance of the area under the curve of statical stability or the GZ curve? Explain using a neat diagram, how this curve is used to assess the stability of the ship against a heeling arm.

(b) In a grain carrier, how the shifting of grain affects the curve of statical stability. With a neat diagram explain the existing minimum criteria for stability of grain carrying ships. (8).

Q1. (a) List out the merits and demerits of longitudinal framing system. Explain which demerits of longitudinal framing system are mitigated by use of mixed framing system without affecting the merits?

(b) List and explain with a sketch the type of loads and failure mechanism that would be of concerns for the longitudinal strength of the hull girder of a bulk carrier

Q6. (a) Describe how bulkheads are tested.

(b) A double bottom tank containing seawater is 6m long, 12m wide and 1m deep. The inlet pipe from the pump has its center 75mm above the outer bottom. The pump has a pressure of 70 kN/m2 and is left running indefinitely. calculate the load on the tank top:

 (i) If there is no outlet.

(ii) If the overflow pipe extends 5m above the tank top.

Q7. A. Describe the effect of cavitation’s on the propeller blades.

B. A propeller 4.6m diameter has a pitch of 4.3m and boss diameter of 0.75. The real slip is 28% at 95 rev/min. Calculate the speed of advance, thrust and thrust power.

Q8. A ship of 9,900 tonnes displacement has KM=7.3 m and KG=6.4 m she has yet to load two 50 tonne lifts with her own gear and the first lift is to be placed on deck on the inshore side (KG 9 m and center of gravity 6m out from the center line). When the derrick plumbs the quay its head is 15m above the keel an 12m out from the center line.

Calculate the maximum list during operation.

Q9. (a) Describe how thrust power is determined. (6)

(b) The following information relates to a model propeller of 400mm pitch:

(i) Plot curves of thrust and torque against rev/min

(ii) When the speed of advance of the model is 150 m / min and slip 0.20, calculate the efficiency.

Q9. With respect to Ship Propulsion:

a. Explain the various efficiencies associated with propeller and shafting arrangement.

b. When a propeller of 4.8 m pitch turns at 110 rpm, the apparent slip is found to be —S % and the real slip is 1.5 S %. If the wake speed is 25 % of the ship speed, calculate the ship speed, apparent slip and the real slip.