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Q2. Vessel has gone through very heavy weather. On arrival at safe anchorage, you are conducting your inspection to determine damages to hull.

A. List the areas you will inspect. (3)

B. List your findings of any significance. (6)

C. Write a report to company suggesting repairs if any. (7)

Q1. 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. (20)

Q1. Discuss the validity of EACH of the following statements with respect to large slow speed diesel engines:

A. Bearing clearances obtained by taking leads (or use of plastic inserts) are fundamentally more accurate than those obtained with the use of feelers.

B. Bearing wear down can be measured by taking deflections.

C. A timing chain should be renewed when its slackness causes late fuel injection and exhaust valve operation.

D. Timing chain slackness is solely due to stretch of the link plates.

Q1. Differentiate with the aid of simple sketches between two of the following types of electronic circuits.

A. Rectifier circuit (6)

B. Amplifier circuit (5)

C. Oscillator circuit (5)

Q4. A. Explain the possible reasons T/C vibration while operating at a steady speed.

B. State how the incidence of turbo charger vibration might be minimized.

C. Explain the action to be taken in order to maintain 2 stroke engine operation in the event of turbo charger having to be taken out of service.

D. Indicate the effect this action will have on engine operation.

{How is the engine operation affected when operated with a by-passed T/C}

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.

Q4. Explain how the period of roll varies with:

A. The amplitude of roll. (4)

B. The radius of gyration. (4)

C. The initial metacentric height. (4)

D. The location of masses in the ship. (4)

Q8. (a) Sketch a sealing arrangement for an oil lubricated stern tube. (4)

(b) Identify the common forms of seal failure. (4)

(c) State how oil loss due to seal failure can be restricted whilst on Passage. (4)

(d) How the aft bearing is designed to minimize the concentrated load? (4)

Q2. Explain the advantages and disadvantages of an inert gas smothering system from flue gasses compared to an inert gas generator. Explain why inert gas generator is more advantageous. Why it is unsuitable for use in machinery spaces. (20)

Q2. A. Explain in detail, how an underwater survey is carried out.

B. State the requirements to be fulfilled before an underwater survey is acceptable to the survey authority.

C. Construct a list of the items in order of importance that the underwater survey authority should include.

Q5. With reference to U.M.S. operation:

A. State with reasons the essential requirements for unattended machinery spaces. (8)

B. As second Engineer, describe how you would respond to the irretrievable failure of the Machinery space fire alarm system whilst the ship is on voyage. (8)

Q7. Compare the destructive testing done on engineering materials with non-destructive testing done on engineering components. Briefly describe one destructive test and two non-destructive tests to illustrate your answer

Q3. With reference to main air turbochargers. (16)

a) Give a reason why binding wire is frequently fitted near the top of the blades.

b) Mention one fault that occasionally develops with binding wire in services.

c) Define the cause and identification under running conditions of turbine blade damage.

d) State how (c) can be largely avoided.

Q9. (a) Why is the axial clearance of a main thrust bearing an important dimension? (6)

(b) How is this clearance measured? (6)

(c) Describe how the thrust pads are removed for inspection and state what you would look for in particular. (4)

Q3. With reference to Underwater Inspection in lieu of Dry docking (UWILD)

A. Explain in detail, how an underwater survey is carried out. (6)

B. State the requirements to be fulfilled before an underwater survey is acceptable to the survey authority. (5)

C. Construct a list of the items in order of importance that the underwater survey authority should include. (5)

Q3. Explain the matching of an induction electric motor to a pump required for main circulating duty, with the aid of pump characteristic and torque/slip diagrams. (16)

Q3. a) State the advantages of using steam turbine propulsion power for vessels carrying L.N.G. cargo. (8)

b) With regard to the use of L.N.G. cargo as boiler fuel explain: (8)

(i) The safety precautions relating to the gas pipeline supplying the boiler and burning the gas in the boiler.

(ii) The means of getting rid of “excess gases” during loading or discharge.

Q1. a) Describe a method of the attachment of bilge keels. (5)

b) State THREE reasons for not extending bilge keels the entire length of the vessel. (6)

c) Explain TWO principles of roll damping that bilge keels exploit. (5)

Q4. a) Comment on the reliability and maintenance requirements of two the following.

(i) Pneumatic control equipment

(ii) Electro-mechanical control equipment

(iii) Electronic control equipment. (12)

(b) Discuss the routine attention required and the defects, which may occur in service. (4)

Q4. With reference to a three-phase shipboard electrical distribution system: (16)

a) Enumerate the advantages of an insulated neutral system.

b) Enumerate the disadvantages of an insulated neutral system.

c) Describe how the earthed neutral system is Earthed.

d) Compare the use of an insulated neutral system as opposed to the use of an Earthed neutral System with regard to the risk of electric shock from either system.

Q7. A. Draw a block diagram for a fully automated accommodation air conditioning unit, labelling the component parts and indicating the directions of air flow. (8)

B. Explain why the unit includes means of dehumidification and humidification. (4)

C. A chart is used for ensuring that the accommodation conditions are within the so-called Comfort Zone: what useful information does the chart give? (4)

Q5. a) Sketch a magnetic overload device incorporating a dashpot and explain how the current and time settings of the device may be varied. (8)

b) With the aid of a sketch outline the essential features of a three stage “preferential tripping” scheme for the main generators of a ship. (8)

Q5. With reference to LNG diesel engine installations:

(a) Describe, with the aid of a sketch, a Gas Valve Unit, explaining its purpose and indicating where it is located in the gas train. (6)

(b) Explain why ventilation and inert gas systems must be installed with the engine fuel gas system. (5)

(c) State why pilot injection must be provided when burning fuel gas, explaining how a pilot injection system works (5)

Q5. List SIX hazards that arise with the carriage of liquefied gas in bulk. Describe, with the aid of a sketch. The details of construction of a prismatic cargo tank within a gas carrier designed to carry liquefied gas (LPG)

Q5. With reference to a periodically unattended machinery space of a dry cargo vessel discuss the requirements for.

A. Protection against flooding. (10)

B. Control of propulsion machinery from the navigating bridge. (10)

Q5. (a) Suggest four reasons why the temperature of the oil in the steering gear system may become excessive.

(b) With reference to steering gears explain how the ship may be steered in each of the following circumstances.

(i) Destruction by fire of the primary supply cable.

(ii) Destruction by fire of the telemotor lines.

(iii) Bearing failure in the running pump.

Q5. A. Explain the ideal design requirements of a ship’s propeller. (8)

B. Briefly describe the propeller maintenance that should be carried out to prevent the fuel being wasted. (8)

Q6. a) Describe Ingress protection rating and types of insulation. (6)

(b) A total load of 8000 kW at 0.8 power factor is supplied by two alternators in parallel. One alternator supplies 6000 kW at 0.9 power factor. Find the kVA rating of the other alternator and the power factor. (10)

Q6. 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)

Q6. A) Describe the procedure for opening a bottom end bearing for inspection making reference to the positioning of the crank and the safety precautions to be observed.

B) State how the bearing clearance may be checked and adjusted when necessary

C) State TWO defects, which may be encountered during inspection of the bottom end bearing and crankpin giving possible causes of EACH.

D) State TWO checks, which should be made before returning the engine to service following overhaul of the bottom end bearing.

Q7. A. Describe the preparation necessary before the application (in dry dock) of sophisticated or approved long life coating to the underwater surface of the hull. (6)

B. State the significance of the roughness profile. (5)

C. List the different sophisticated coatings which are available. (5)

Q7. With reference to electronically controlled engines:

(a) Describe how fuel injection quantity and timing is adjusted. (6)

(b) Describe how the exhaust valve timing may be varied. (5)

(c) Describe how starting air valves are regulated. (5)

Q7. 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. (4)

B. Main switchboard. (4)

C. Lifeboat. (4)

D. Oily water separator. (4)

E. Navigational lighting. (4)

Q7. A) Electric motors contain a stationary member as well as a rotating member. For each of the following machines, identify in which part of the motor three field winding and the armature winding are located: three phase induction motor, three phase synchronous motor, D.C. motor. (6)

B) A 220 V, D.C. shunt motor has an armature resistance of 0.5 ohm and an armature current of 40 A on full load. Determine the reduction in flux necessary for a 50 per cent reduction in speed. The torque for both conditions can be assumed to remain constant. (10)

Q7. An Auxiliary boiler is periodically unattended and equipped with alarms to cover low water level, high steam pressure, and air and flame failure.

A. State why and how fuel the burners are automatically cut off under alarm conditions of water level, steam pressure, air and flame failure.

B. Describe how and when each of the above alarms is tested without endangering the boiler.

Q8. a) Describe the inspection, which is required to be carried out in the dry-dock after the stern of a ship has heavily struck a dock wall. (8)

b) The propeller is found to be damaged, and it is decided to fit the spare propeller. Describe the process and mention the precautions to be taken to ensure correct assembly. (8)

Q4. With reference to shaft alignment:

(a) Explain the meaning of fair curve or rational alignment. (8)

(b) Shaft alignment is often verified using hydraulic jacks to obtain a simple graph. Sketch such a graph, indicating the following:

(i) Static load

(ii) Hysteresis

(iii) Influence number

(c) Explain the limitations of checking shaft alignment solely by hydraulic jacking methods. (8)

Q8. You have to instruct a newly joined fifth engineer to bring 5 liters of Carbon- remover from 20 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.

Q8. a) Show how the power that is transferred across the air gap of the three-phase induction motor is represented. Explain the terms. What portion of this is useful power? (6)

b) A 440 V load of 400 kW at 0.8 (lagging) power factor is jointly supplied by two alternators A and B. The kW load on A is 150 kW and the KVAr load on B is 150 KVAr (lagging). Determine the kW load on B, the KVAr load on A, the power factor of operation on each machine and the current loading of each machine. (10)

Q4. Sketch and describe the arrangement of a main engine camshaft chain. Describe the repair procedure following fracture of one chain link during operation of the engine. Give possible reasons for the failure and explain how the chain is set initially at the correct degree of tension. (16)

Q9. a) State why onboard testing of fuel oil whilst taking bunkers can be advantageous. (4)

b) State how a representative fuel sample may be obtained during the bunkering operation. (4)

c) Explain how EACH of the following is formed during the combustion of fuel: - (4)

(i) Oxides of Nitrogen, NOx (ii) Carbon Monoxide, CO (iii) Oxides of Sulphur, SOx

d) State how the effects of sulphurous products of combustion on the engine system may be reduced. (4)

Q9. (a) Define proportional control action. (4)

(b) Sketch and describe a simple pneumatic proportional controller. (4)

(c) State a process where a proportional controller may be employed. (4)

(d) State the disadvantage of proportional only action. (4)

Q9. (a) Define the term Torsional Vibration with respect to an engine crankshaft, stating the effect that high levels can have on an engine crankshaft. (6)

(b) Explain how engine deterioration influences the risk of Torsional Vibration, stating what can be done to minimise that risk. (5)

(c) Explain TWO possible reasons for the activation of a Torsional Vibration alarm after an engine has been started if there had been no previous history of such an alarm and if no maintenance had been undertaken on the engine whilst it was stopped. (5)

Q9. Write reference to gravity life boat davits:

(a) Explain load testing of life boat davit

(b) State the purpose of the following:

(i) Centrifugal brake.

(ii) Dead man’s handle.

(iii) Davit limit switch.

Q9 a) Explain the preference for a 60 Hz system. Describe the dangers of running a 50 Hz system from a 60 Hz supply. (6)

b) A ring-main, 900m long, is supplied at a point A at a p.d. of 220V. At a point B, 240m from A, a load of 45A is drawn from the main, and at a point C, 580m from A, measured in same direction, a load of 78A is taken from the main. If the resistance of the main (lead and return) is 0.25 ohm per kilometre, calculate the current which will flow in each direction round the main from the supply point A and the potential difference across the main, at the load where it is lowest. (10)

Q10. a) (i) What is direct-connected alternator? (3)

(ii) How is a direct-connected exciter arranged in an alternator? (3)

b) Find the synchronous impedance and reactance of an alternator in which a given field current produces an armature current of 200 A on short circuit and a generated e.m.f. of 50V on open- circuit. The armature resistance is 0.1 ohm. To what induced voltage must the alternator be excited if it is to deliver a load of 100A at a p.f. of 0.8 lagging, with a terminal voltage of 200V. (10)