DieselShip's Online Content Library

Q1. An auxiliary engine under load continuously fluctuates even with a steady load. The fault you diagnose could be owing to: (16)

(a) The quality of fuel

(b) The quality of servicing of the governor in the last port

(c) The supply of charge air

(d) The overhaul of fuel injectors done in the last decarbonisation.

Give a brief explanation as to why each of the above mentioned points either could be true or cannot at all be the reasons for such a fluctuation.

Q2. With reference to a 2- stroke slow speed main propulsion engine, sketch a line diagram showing the air starting system:

(a) State, with reasons, three safety features incorporated in an air starting system. (8)

(b) State with reason why an engine may fail to turnover on air (8)

Q3. a) How is the number of Carbon Dioxide (CO2) bottles required for a ship calculated for (i) machinery spaces and (ii) cargo spaces? (12)

b) What means are provided to prevent the inadvertent release of CO2 in the engine room or other protected spaces? (8)

Q3. Discuss the precautions, which can be taken to minimize the possibility of a diesel engine crank case explosion and the transmission of dangerous flame into the machinery space.

(a) By design and equipment (8)

(b) By operating personnel (8)

Q4. (a) What are the causes of Turbocharger surging? How is it indicated to the watchkeeper? (8)

(b) What are the possible remedial action? (4)

(c) What are the reasons for excessive fouling of the turbocharger? (4)

Q5. With reference to the diesel prime movers for generators in unmanned machinery spaces:

(a) Outline the monitoring and control equipment designed to protect the engine. (8)

(b) Describe the methods employed to test the monitoring and control equipment, during a routine check. (8)

Q5. a) The current transformer (CT) and potential transformer (PT) or voltage transformer are both measuring devices. List their shipboard application. (6)

b) Sketch and describe any one type of current transformer. (10)

Q6. a) What are the safety devices provided on the steering gear system? (10)

b) What is the significance of the shaft hull earthing device on the shafting? (6)

Q6) (a) Describe the constructional features of plate type freshwater generator and its operational procedures for freshwater generation. (6)

(b) State the temperatures and pressures at salient points. (4)

(c) State some of the advantages and limitations that exist in using a plate type heat exchanger. (6)

Q9. a) Explain Fleming's Right hand rule. (6)

b) A one-turn armature coil has an axial length of 0.4m and a diameter of 0.2m. It is rotated at a speed 500 rev/min in a field of uniform flux density of 1.2 T. Calculate the magnitude of the e.m.f. induced in the coil. (10)

Q8. a) Describe in detail the method used to measure the capacitance of a capacitor.(6)

b) A circuit has a resistance of 3R and an inductance of 0.01 H. The voltage across its ends is 60V and the frequency is 50Hz. Calculate (a) the impedance. (b) the power factor (c) the power absorbed.(10)

Q7. a) What is the difference between a DC Generator and a DC motor? (6)

b) A 4-pole, 32 conductor, Lap-wound DC shunt generator with terminal voltage of 200 V delivering 12 A to the load has ra = 2 and field circuit resistance of 200 Ω. It is driven at 1000 RPM .

a) Calculate the flux per pole in the machine. (6)

b) If the machine has to be run as a motor with the same terminal voltage and drawing 5 A from mains, maintaining the same magnetic field, find the speed of the machine. (10)