DieselShip's Online Content Library

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.

Q8. Explain in detail a fixed gas fire extinguisher system, indicating the quantity of the fire-extinguishing medium, the controls required for the system, installation requirements and training required to bring the system to be readily operated.

Q1. Describe a suitable means of withdrawal procedure for the removal of keyless propellers.

Q2. Explain the methods used to control the speed of a 3 Phase induction motors. Draw and Explain a Variable Frequency Drive used for optimization of energy efficiency of auxiliary machineries on board vessels.

Q2. Explain with a sketch “speed droop” in a governor; Answer the following

A. How is a main engine governor different from an auxiliary engine governor?

B. Explain how load is transferred to an incoming generator explaining your actions with relation to the governor’s “droop line”.

Q1. You have recently joined a vessel as Second Engineer Officer. For the past several voyages it has been the practice on board to dispense with the use of the exhaust gas boiler and leave it to run dry. As part of an overall economy drive the company wanted to re-commission the exhaust gas boiler. Explain as a second engineer officer, what inspections, checks, recommendations and precautions you will exercise/ensure for this exhaust gas boiler with regard to re-commissioning and bringing this exhaust gas boiler into service. how exhaust gas boiler safety valves adjusted.

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.

Q1. Explain the advantages and disadvantages of an inert gas smothering system from flue compared to an inert gas generator. Explain why inert gas generator is more advantageous.
Why it is unsuitable for use in machinery spaces. (20)

Q6. A marine diesel engine fresh water cooler end cover is badly corroded and holed. Other than replacing it, suggest some measures of repairing it (a) while in operation. (b) When not in operation. Repair procedures must be effective. practicable and innovative.

Q8. Explain why the use of residual fuels for the operation of large slow speed or of medium speed engines, may be responsible for the following problems with turbocharger nozzles, shrouds and blades and how in each, the problem may be minimized:

A. Build-up of deposits.

B. Hot corrosion.

C. Erosion (16)

Q2.A. Explain how analysis of used lubricating oil can be used as a “health-monitoring” tool for diesel engines.

B. Describe how vibration measurement can be used with a main engine turbo-charger:

i. For fault analysis;

ii. For condition monitoring with respect to maintenance;

iii. As a substitute to opening up machinery for survey.

Q1. With respect to the High Voltage power systems installation, explain the different types of circuit breaker that are used, comparing them on merits and de-merits. Describe the theory of arc phenomenon and the mechanism fitted to mitigate the arc.

Q4. With reference to the Maritime Labour Convention (MLC) 2006, discuss the requirements for seafarers regarding.

A. Seafarer employment agreements    B. Repatriation. C. Seafarers Wages.

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.

Q7. Name various statutory Certificates and Documents to be carried on board Crude Oil Tankers giving a reference to the conventions and justify for their requirement. (20)

Q6. With Reference to Main Engine Fuel Pumps.

(a) Explain how the setting of a variable injection timing fuel pump is checked and adjusted.

(b) State why it may be necessary to adjust the settings of a variable injection timed fuel pump.

Q3. Diesel electric propulsion is now being chosen as the power plant for an increasingly wide variety of vessels.

(a) Sketch a simple layout of such an installation.

(b) Explain the advantages of selecting such a plant.

Q7. Sketch and Discuss the precautions and protections that are provided 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; B. By operating personnel

Q6. With regards to main transmission shaft flange coupling arrangements:

A. Sketch a hollow type coupling bolt and the hydraulic head/nut and loading rod which are used to fit it.

B. Describe how the bolt is fitted.

C. State the advantage of the hollow coupling bolt as compared to the traditional type of coupling bolt.

Q4. Describe a forced ventilation system for the machinery spaces and a natural ventilation system for a lower hold. Why hold ventilation is considered necessary?

Q5. With reference to an emergency source of electrical power in cargo ships: -

A. Describe a typical power source.

B. Give a typical list of essential services, which must be supplied simultaneously;

C. Explain how the emergency installation can be periodically tested.

Q5. A.  During the weighment of CO2 bottles required for total flooding of Engine room, it was observed that few bottles are less than the original capacity.  State the reasons for the same and checks / tests to be made prior refilling;

B. State how often the CO2 bottles are required to be weighed and pressure tested.

Q4. Enumerate the causes of vibration in diesel machinery and shafting. Describe procedures by which it may be reduced by operating personnel, suitable design and devices. State the possible effects of vibration on machinery and crewmembers.

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.

Q4. With reference to the prevention of hull corrosion discusses:

A. Surface preparation and painting of new ship plates.

B. Design of the ships structure and its maintenance. C. Catholic protection by sacrificial anodes, of the internal and external areas of the ship.

Q8. With reference to a periodically unattended machinery space of a dry cargo vessel discuss the requirements for.

A. Protection against flooding.

B. Control of propulsion machinery from the navigating bridge.

Q5. With reference to alkaline batteries used on board ship.

A. Describe the operation of a battery cell and state the material used;

B. Describe how the cells are mounted to form a battery;

C. State the advantages and disadvantages compared with lead-acid batteries.

Q5. Express your reactions and state the subsequent investigation you would make if a laboratory report on a used diesel engine oil sample indicated the presence of appreciable amounts of: -

A. Iron; B. Copper, Antimony and Tin; C. Silicon.

Q5. Name the factors an engine designer considers in the selection of the compression ratio for a compression ignition engine. Give some examples of compression ratio values.

Q7. A. Explain why centrifugal pumps cannot handle air or vapours to effect priming yet turbo- blowers operating on the same principle can.

B. If a vessel is fully laden, how may it be ascertained that the fire pump priming arrangements would operate satisfactorily in the ballast condition.

C. Explain a suitable method of priming suitable for a centrifugal pump.

Q6. A. Describe briefly the significance of the factor of sub-division;

B. A box shaped vessel 65m X 12m X 8m has KG 4m and is floating in self water upright on an even keel at 4m draft F and A. Calculate the moments of statically stability at i. 5 degrees and ii. 25 degrees’ heel.

Q8. With reference to activated fin stabilizers give reasons why:

(a) For large vessels such units are preferred to passive tanks; (6)

(b) These units are preferred for passenger and fast cargo ships; (6)

(c) Partial rather than maximum damping of ship movement in heavy weather is advisable for reasons other than overstressing of fin stocks and activating gear. (8)

Q2. Write short notes on following:

A. Magnetic Particle Inspection (MPI)

B.  Ultrasonic Testing (UT)

C. Radiographic Testing (RT).

Q9. A. Explain the potential hazards if liquid-cooled transformers are used.

B. What are the losses in transformers? Mention the various factors which affect these losses. In a 25 KVA, 3300/233 V, single phase transformer, the iron and full-load Cu. Losses are respectively 350 and 400 watts. Calculate the efficiency at half-full load, 0.8 power factor

Q6. A. State the various types of indicator diagrams that are used to assess engine performance; B. Specify the additional data needed in conjunction with these diagrams; C. Explain, how some abnormalities in indicator diagrams can be traced to the indicator; D. Describe the precautions necessary to avoid indicator malfunctions.

Q4. With reference to hydraulic steering gears, sketch and describe each of the following: (A)Single failure concept;

(B)100 Percent redundancy.

Q9. A) Describe the effect of cavitations on the propeller blades. (6)

B) A propeller 4.6m diameter has a pitch of 4.3m and boss diameter of 0.75 m. The real slip is 28% at 95 rev/min. Calculate the speed of advance, thrust and thrust power.  (10)

Q8. Explain the principle of port State control and give in detail the verification the State control Officer may carry out with particular reference to the following:

A. Emergency generator;

B. Main switchboard;

C. Lifeboat;

D. Oily water separator;

E. Navigational lighting.

Q7. A. Describe how protection against short circuit is provided in a 3 phase induction motor circuit.

B. Explain how rotating magnetic field is produced in three phase winding with three phase supply. A 4-pole, 3-phase induction motor operates from a supply whose frequency is 50 Hz. Calculate

(i) Speed at which the magnetic field of the stator is rotating,

(ii) speed of the rotor when the slip is 0.04,

(iii) the frequency of the rotor current when the slip is 0.03.

Q2. With reference to Marine Diesel engines:

(a) Describe how crankshaft alignment is checked.

(b) Identify with reasons the causes of crankshaft misalignment.

(c) State how the measurements are recorded.

Q7. A. State, with reasons, THREE properties required of crankcase oil which is to be used for a trunk piston main engine.

B. Explain how a representative sample of crankcase oil would be obtained from a trunk piston engine. C. Briefly describe the action to be taken if the crankcase oil charge cannot immediately be replaced and analysis shows – (i) Water is present; (ii) Alkalinity has fallen; (iii) Viscosity has changed appreciably; (iv) Carbon content has increased.

Q5. A. State why fixed pitch propellers have a poor efficiency when going astern.

B. With reference to controllable pitch propellers state:

i. Why is it preferable that the main servomotor be housed in the propeller hub rather than in the shafting forward of the propeller shaft?

ii. What regular maintenance and checks should be carried out to ensure maximum reliability of the gear at all times?

Q8. You have to instruct a newly joined fifth engineer to bring 5 liters of Carbon- remover from 200

litre drum. Explain him:

a) Precautions to be taken while handling.

b) Measures to be taken if:

i) Chemical contacts his skin.

ii) Chemical contacts his eyes.

Q10. A) Describe the stability requirements of a ship for dry-docking. (6)

B) A ship 130m long displaces 14000 tonne when floating at draughts of 7.5m forward and 8.10m aft. GML – 125m, TPC – 18, LCF-3m aft of midships. Calculate the final draughts when a mass of 180 tonne lying 40m aft of midships is removed from the ship. (10)

Q8. A. What is meant by “Resonance” in RLC circuits? Compare the series and parallel resonance circuits.

B. Find the frequency at which the following circuit resonates.

Q9. Severe engine vibration has recently become evident when the main engine for which you are responsible operates within a certain speed range –

A. State, with reasons, the possible causes of such vibration;

B. State the consequences of operating the engine under such vibratory conditions;

C. Describe the procedure you, as Second Engineer, would implement in order to investigate and rectify the problem.

Q6. A. A number of main engine cylinder covers have been subjected to cracking during the preceding four months –

i. Explain possible reasons for this cracking;

ii. State with reasons the action you, as Second Engineer, would take in order to reduce the possibility of future cylinder cover cracking.

B. Cylinder liner wear has increased appreciably during the past six months. Write a brief report to the engineering superintendent concerning this matter explaining the possible causes the immediate action taken to deal with the problem and the action you, as Second Engineer, intend to take in order to reduce the risk of future incidents.

Q5. A. Describe a transverse bow thrust unit using CPP, mention how it should be made to support and how the strength of thrust and reverse thrust are achieved;

B. State with reasons, a suitable prime mover for the controllable pitch propeller;

C. State whether the thrust unit delivers a relatively low pressure head with high volume output or high pressure head with low volume output.

Q9. Write reference to gravity life boat davits; state the purpose of the following:

A. Centrifugal brake, B. Dead man’s handle; C. Davit limit switch.

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. Explain What is meant by, and the significance of, four of the following terms.

I. Voltage Stabilization,

II. Filter choke;

III. Impedance,

IV. Rectification,

V. Grid bias voltage.

Q9. What are the effects of following on the sluggishness of steering gear operations;

A. Air entrapped in hydraulic oil;

B. Worn pins and weak springs in hunting gear;

C. Shock valves leaking

Q9. A.  Difficulty has been experienced in maintaining engine speed at the set value; State THREE possible causes. State how each of these causes may be detected.

B. Describe the action to be taken in order to ensure safe operation of the main engine plant in the event of complete failure of the remote control and sensing equipment.

Q9.  Reverse osmosis is one of the alternative method for shipboard production of drinking water.

(a)  Describe using simple diagrams if necessary,  the principle of reverse osmosis.

(b) (i) Sketch a line diagram showing a single pass system for producing fresh water from sea water

(ii) Describe such a system.

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.

10. How does the change in rotor-frequency affect the induction motor when the load is changed from no-load to full-load?

B. The total input power to a 500 V, 50Hz, 6-Pole phase induction motor running at 975 rpm is 40kW. The stator losses are 1 kW. Friction and windage losses are 2 kW total. Calculate (i) Slip, (ii) Rotor Cu Loss, (iii) Efficiency