DieselShip's Online Content Library

Q4. Explain each of the following:

A. Why wear down in main bearings is critical to the condition of the crankshaft and propeller shaft system.

B. Why total reliance is placed on frictional grip in conventional built up crankshaft

C. Why hole oils are given large fillets in crankpin and journals.

Q4. A. Describe a method of the attachment of bilge keels;

B. State THREE reasons for not extending bilge keels the entire length of the vessel;

C. Evaluate the effectiveness of bilge keels for large wall sided vessels;

D. Explain TWO principles of roll damping those bilge keels exploit.

Q1. A. (i) discuss the various hazards and problems which are associated with electric cable insulation in the event of fire;

(ii) Suggest remedies for these problems.

B. State how the spread of fire may be reduced by the method used for installing electric cables.

Q1. What is understood by risk on board ship? As a 2nd engineer discuss various methods for hazard identification and assessment of risk available on board.

Q3. Differentiate between squirrel cage and wound rotor motor of the three phases: a.c. induction. In respect of the following; A. Rotor construction, B. Torque characteristic, C. Speed variation.

Q1. Explain the reason why the modern camshaft-less engines are known as intelligent engines. Describe briefly. The advantages and reliability of such an engine in comparison with the conventional marine diesels engines

Q2. A. Describe the procedure to be adopted for the inspection of a safety valve fitted to an exhaust gas fired auxiliary boiler stating, with reasons, which parts should receive particularly close attention.

B. Describe the procedure for the setting of safety valves of exhaust gas operated auxiliary boilers;

C. Explain the required action a watch-keeping engineer should take after the setting of safety valves as in (B)

Q3. Ships are provided with an independent diesel or electric or air operated emergency fire pump.

(a) State three areas in which emergency fire pump are commonly installed and give reasons why?

(b) Describe with aid of a simple sketch an air pump or primer used to initiate suction when the fire pump is situated above sea water level.  What suction lift would you expect from a single stage pump system?

(c) State the water jet capacity the pump must be capable of.

(d) State how it can be ensured that the fire pump is kept in good working order.

(e) State what precaution must be taken in sub-zero temperatures?

(f) Using a simple sketch describe with reasons, how the emergency fire pump is connected to the ship’s fire main showing position of any isolation valves fitted and location of international shore connection

Q3: With reference to dry docking, define the responsibility of the second engineer;

A. Prior to docking;

B. Whilst the vessel is in dry dock;

C. Prior to flooding and leaving the dock.

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.

Q2. Discuss on optical and acoustic methods of non-destructive testing

Q2. Explain EACH of the following; A. Effect of worn out main bearings on the condition of the crankshaft and propeller shaft system

B. The reliance on frictional grip in conventional built up crankshaft. C. The reasons for providing large fillets to oil holes in crankpins and journals

Q2. With reference to the carriage and pumping of liquefied gas cargo:

A. Sketch a suitable pumping system labelling the component parts;

B. State;

i) Why submerged hydraulically driven pumps are not used;

ii) How overheating of pump drive shaft bearings is avoided;

C. State, how the risk of fire and explosion in cargo tanks is obviated both in the loaded and discharged condition.

Q1. With reference to International Load Line Statutory Certification,

A. State the reasons for the freeboard requirements;

B. (i) Explain the term “conditions of assignments”;

(ii) List the items that may be examined during a Load line survey after a vessel’s major repairs in the dry-dock.

Q5. In engine rooms that are operated under UMS conditions describe with the aid of sketches how the following are monitored:

A. The perforation of a high-pressure fuel pipe;

B. The imminence or possibility of a scavenge fire;

C. Condition that may be conducive to a crankcase explosion

Q1: A number of main engine exhaust valves have suffered cracking during the preceding four months A. Explain possible reasons for cracking; B. State with reasons the instruction, you as second engineer, would issue in order to reduce the possibility of future cylinder cover cracking

Q3. The direct online start of squirrel cage motor is used for most electrical drives on a.c. powered ships. Describe with sketches as necessary one method of overcoming each of the following Problems:

A. High starting current; B. Low starting torque.

Q2. A. Outline the problems associated with improper lubrication of the liner and piston assembly of a large slow speed engine.

B. Describe and state the causes of each of Clover leafing and Micro-seizure

C. List out the composition of a cylinder oil suitable for an engine operating on VLSFO.

Q6. With reference to electro-hydraulic steering gears:

A. Explain in terms of control parlance, the function of the “Hunting gear”;

B. Explain the consequences if the standby pumping unit is motored;

C. State TWO methods employed to prevent the standby hydraulic pump being motored by the operating unit.

Q4. With reference to MARPOL Annex IV; A. Draw a biological sewage treatment plant and explain the principal of operation B. Periodical maintenance and checks and tests required to be done to verify the effectiveness of the above system.

Q2. State how and why the following machinery items are effected when the maximum service speed of a Vessel is consistently maintained in heavy weather.

A. Intermediate shafting,

B. Propeller shafting,

C. Shafting coupling bolts,

D. Main thrust pads.

Q4. An auxiliary engine exhibits a tendency to hunt to such an extent that the engine speed variation prohibits the connection of the machine to the switchboard. A. Discuss the possible causes of hunting; B. Explain how the problem of hunting can be rectified.

Q4. A. (i) Discuss the various hazards and problems which are associated with electric cable Insulation in the event of fire.

(ii) Suggest remedies for these problems.

B. State how the spread of fire may be reduced by the method used for installing electric cables.

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.

Q8. A. Explain the necessity of intercoolers on a multi-stage compressor. What attention is required to keep them safe and in good working order? Sketch and describe an intercooler suitable for a 2400kPa compressor and state materials used.

B. What attention is needed before opening up an air compressor for inspection?

C. What faults are likely to develop in an air compressor and how are they remedied?

Q2. A. Describe the arrangement made in a main structural bulkhead for a watertight door aperture; B. Explain a procedure for ensuring that sliding watertight doors are operated safely. C. Differentiate between the categories of watertight door and state the regulation pertaining each type.

Q9. A) As Second Engineer of a new ship, prepare standing orders for all future bunkering operations;

B.  State why it is very important to obtain a representative sample of heavy fuel bunkers taken and explain how a representative sample is obtained

C. What information is provided in bunker Delivery note (BDN).

Q8. For a fully automatic provisions refrigeration system incorporating a number of rooms; A. Explain how each room temperature is set;  B. Describe the sequence of events following a demand for increased refrigerant flow from one room;  C. State with reasons the devices incorporated into the system to protect the machinery and equipment against malfunction;  D. State how satisfactory operation of the plant can be established?

Q5. A. What are the causes of overheating of an induction motor?

B. What preventive measures are provided against damage to an induction motor in installed condition? C. What is the purpose of ‘fuse back up protection’ provided to an induction motor? D. How does an induction motor develop torque?

E. What is the condition to be satisfied for achieving maximum running torque in an induction motor?

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.

Q8. Explain how the ingress of sea water is prevented in an oil lubricated stern bearing system. Should the system fail, describe the corrective action possible whilst the vessel is afloat. State why two stern bearing oil header tanks are fitted in some instances?

Q6. a) Describe how the distribution of mass within the ship affects the rolling period. (6)

b) The righting moments of a ship at angles of heel of 0, 15°, 30°, 45°, and 60° are 0, 1690, 5430, 9360 and 9140 kN-m respectively. Calculate the dynamical stability at 60°. (10)

Q6. With respect to MARPOL 73/78, Annex - II, Noxious liquid chemicals are divided into categories; A. State the number of categories, and what does each category signify. B. State the requirement of Procedures and Arrangements Manual, and what information is available.

Q5. With reference to air receivers and bottles explain with reasons: A. Why regular systematic internal inspection is advisable? B. Which internal areas of large receivers should receive particularly close examination? C. How bottles are inspected internally and what parts should be closely examined? D. How the condition of a bottle or receiver that cannot be inspected internally is checked?

Q6. A. What are the characteristics of PN junction diode? Point out its specifications. Also point out the significance of dynamic and static resistances.

B. Draw the circuit of Half-wave rectifier and its output waveform. A diode whose internal resistance is 20 is to supply power to 1000 load from 110 V (RMS) source. Calculate

(i) peak load current, (ii) DC load current, (iii) AC load current.

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”.

Q9. With reference to multi-tubular heat exchangers explain:

(A) How and where impingement attack is likely to occur in the tubes

(B) Why is it desirable that coolant flow rate should not exceed that required to maintain correct fluid temperature

(C) Ample well-shaped water boxes and smooth tube inlets are desirable

(D) Partial obstruction of tube bore is a common cause of tube failure

Q7. a) Describe briefly the significance of the factor of subdivision. (6)

b) A ship 120m long has a light displacement of 4000 tonne and LCG in this condition 2.5m aft of midships.  (10)

The following items are then added:

Cargo    10000 tonne      LCG 3.0 m          forward of midships

Fuel      1500 tonne        LCG 2.0 m          aft of midships

Water    400 tonne          LCG 8.0 m          aft of midships

Stores   100 tonne          LCG 10.0m         forward of midships

Using the following hydrostatic data, calculate the final draughts:

Q7. With reference to SOLAS ch – XII write short notes on: A. Emergency towing arrangement on tankers; B.  Safe access to tanker bows; C. Safe access to cargo holds, cargo tanks; D. Protective coatings of ballast tanks.

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

Q7. A. Describe the no-load saturation characteristic of a d.c. generator.

B. A d.c. motor takes an armature current of 110 A at 480 V. The resistance of the armature circuit is 0.2 . The machine has six poles and the armature is lap-connected with 864 conductors. The flux per pole is 0.05 Wb. Calculate;

(i) The speed;

(ii) The gross torque developed by the armature.

Q7. A. Describe with aid of sketches the following types of bedplates as used for a large I.C. engine - i. Bedplate cast in section; ii. Fabricated steel Bedplate B. State the stresses to which these bedplates are subjected and explain how bedplates are secured to the hull of the ship.

Q5. With respect to refrigeration gases used on-board vessels, answer the following:

A. Explain Ozone Depleting Potential (ODP) and Global warming potential (GWP) of conventional refrigerant gases.

B. Name the alternate refrigerant gases available and being used onboard.

C. Explain the steps you will take to ensure that release of refrigerant gases from the plant in minimized during normal operation and during maintenance activities.

Q8. A) Explain how the distribution of masses affects rolling and pitching. (6)

B) A ship turns in a circle of radius 100 metres at a speed of 15 knots. The GM is 2/3 metres and BG is 1 metre. If g = 981 cm/sec2 and 1 knot is equal to 1.8532 Km/hour, find the heel due to turning. (10)

Q3. With reference to SOLAS Ch-XII (Additional safety measures for bulk carriers);

A. Damage stability requirements for bulk carriers;

B.  Structural requirements for bulk carriers;

C. Water ingress alarms.

Q7. It is found that the tie rods are persistently becoming slack: A. State, with reasons, the possible causes; B. State, with reasons, the likely effects on the engine if it is allowed to operate with slack tie rods; C. Explain how this problem can be minimized?

Q8. A. What is a commutator? Discuss its rectifying action in detail.

B. Calculate the e.m.f. generated by a 4-pole, wave wound armature having 40 slots with 18 conductors per slot when driven at 1000 r.p.m. The flux per pole is 0.015 wb.

Q8. A. Discuss the principal forces a large diesel engine crankshaft must withstand while in service and how the stresses resulting from these forces are kept within acceptable limits by good design and operation criteria; B. Discuss the manner in which the crankshaft may be overstressed and the consequences arising there from.

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

A. Emergency generator; B. Auxiliary steering gear; C. Lifeboat engine; D. Bilge pumps; E. SOPEP.

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)

Q9. A. State the common causes of scavenges fires; B. List the indications that a scavenge fire is in progress; C. State the immediate action to be taken in the event of a scavenge fire; D. List with reasons the checks and precautions necessary before an engine is put back into service following a scavenge fire.

Q9. A. Discuss different methods of speed control of a d.c. series motor by adjusting field ampere turns.

B. A 230 V, d.c. shunt motor runs at 1000 r.p.m and takes 5 amperes. The armature resistance of the motor is 0.025𝛀 and shunt field resistance is 230𝛀. Calculate the drop in speed when the motor is loaded and takes the line current of 41 amperes. Neglect armature reaction.

Q4. Misalignment of the main shafting between engine and propeller causes bearing overloads and shaft stress;

A. State the difficulties associated with checking shaft alignment and the reasons why results are unreliable due to external factors;

B. Explain with a simple sketch how a bearing load is assessed.

C. Explain how uneven loading could be rectified

Q1. With regard to care of lubricating oils onboard, answer the following:

(a)  Microbial degradation of lubricating oil and measures to prevent the same

(b)  Methods of ensuring correct sampling is done for the purpose of shore based testing.

(c)  If the shore based testing results show an abnormal values of water content and TBN for the crank case lub oil of a slow speed main engine, what will be interpretation and subsequent action?

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)

Q10. A. Why is a synchronous motor not self-starting? What are the various ways in which it can be started?

B. A 500V, single phase synchronous motor gives a net output mechanical power of 7.46kW and operates at 0.9 power factor lagging. Its effective resistance is 0.8 . If the iron and friction losses are 500 w and excitation losses are 800w, calculate the armature current and the commercial efficiency.