DieselShip's Online Content Library

Q1. During a loaded sea passage an unusual noise followed by excessive vibrations were experienced in the engine room of your vessel while she was underway. Vessel is fitted with a four-bladed propeller directly coupled to a 2 stroke Diesel engine. Engine room is located aft. After preliminary investigation and from the engine parameters, you have come to the conclusion that propeller has sustained damage. Write a letter to your company reporting this incidence and justification for your conclusion suggesting future course of action.

Q4. During routine soundings, it is found that leakage into a cofferdam is occurring from an adjacent deep cargo oil tank. As Second Engineer state the procedure for directing safe entry by the engine room staff to ascertain the cause of the leakage. If the leakage persists, discuss EACH of the following options as a possible remedy: i) Leave the cofferdam to flood with oil (ii) Flood the cofferdam with sea water (iii) Seal the Cofferdam and pressurize with air (iv) Pump the leakage to bunker tanks.

Q1. Discuss, with reference to the superheater outlet temperature of the main boiler operating at a constant load, the following statements:

a) An increase in excess air will tend to cause a decrease in superheater outlet temperature due to the cooling effect of more air being introduced.

b) A decrease in economizer inlet temperature will tend to cause a decrease in super heater outlet temperature due to the cooling effect of more water being introduced.

c) Badly fouled generating tube banks will cause an increase in the super heater outlet temperature.

d) Excessive amounts of total dissolved solids in the boiler water will cause variations in the super heater outlet temperature

Q4. W.R.T lubrication of reciprocating Freon refrigerating compressor, A. State with reason the characteristic of the lubricating oil in use in such a system, B. Discuss each of the following W.R.T., Cause effect and remedy - i. Copper plating; ii. Freon cloud point; iii. Freon floc point; C. Sketch a ship indirect refrigeration system arranged for cooling containers stowed in stacks in the hold.

Q5. A. Sketch a four-ram steering gear arrangement capable of 100% redundancy; B. Describe the operation of the arrangement sketched in A.

Q3. Sketch and describe a cargo space inert gas system producing washed gas from either a main boiler or from an independent gas generator module. Elaborate the alarms and cut-outs incorporated in the system to prevent any accident.; Explain the various protections for cargo tanks with respect to pressure vacuum build up inside the tanks.

Q3. A. Sketch and describe TWO methods that employ manometric means for measuring tank contents. (6)

B. State what corrections are made to the readings obtained by the methods described in (A) in order to gauge the mass contents? (5)

C. Explain how bunkering requirements may be estimated when no records of main engine fuel consumption are available on board. (5)

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.

Q9. (a) For Freon-22 vapor compression refrigeration machine, state how each of the following faults are indicated and how they are remedied:

(i) Air in the system

(ii) Moisture in the system

(iii) Undercharge

(iv) Overcharge

(b) Describe with a diagram detailing the devices incorporated into the refrigeration system to protect the machinery and equipment against malfunction.