DieselShip's Online Content Library

Q4. Discuss the need for adequate support of engine room gantry cranes, detailing the following

(a)  Sketch section through the engine room casing showing how the crane is supported by the ship structure;

(b) State what restricts the forward and aft limits of the crane and what is fitted to prevent the crane damaging the forward and aft bulkheads or casing.

(c)  State the Second Engineer’s responsibilities for the engine room gantry crane.

Q6. With reference to an automatic water sprinkler, fire detecting alarm and extinguishing system for accommodation spaces: -

A. (i) Sketch a typical system;

(ii) Describe the operation of this system;

B. State the sources of water available;

C. Describe the sprinkler head and its operation;

D. State how the temperature rating of the sprinkler head is determined.

Q2.  Describe TWO methods of tracing a superficial crack in a marine machinery component; Explain the procedure for arresting propagation of a crack in a machinery component.

Q1. What are semiconductor devices? What are its advantages over thermionic devices? With respect to semi-conductor devices describe working principle and application of the following;-

 A. Zener Diode,

B. Transistor,

C. Photocell,

D. Thyristor

Q1. Sketch and show all parts of a two-stroke engine stuffing box. Describe the procedure of overhauling two stroke engine stuffing box, without removing piston. Answer should include all safety precautions and necessary tools used for stuffing box overhaul.

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?

Q5. With respect to Air Starting systems for 2 stroke diesel engines:

A. Sketch a Main Engine starting air starting system and describe how it operates.

B. List the safety devices and interlocks incorporated in main engine air starting system and state the purpose of each.

Q1. 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.      B. List your findings of any significance.

C. Write a report to company suggesting repairs if any.

Q3. The fire protection provided for the propulsion motor and generator of a diesel electric drive vessel is usually one of the following methods:

a. Fixed foam extinguisher;                   b. Fixed CO2 system;

c. Steam smothering system;                 d. Dry Chemical Powder.

Briefly state in a comparative analysis, how each one of these methods has some disadvantages when used with propulsion system as stated above.

Q1. Describe the procedure for replacing a Main Engine cylinder liner and explain using sketches where necessary, those parts, which require close attention during lifting of cylinder liner. Also describe the procedure for pressure testing the cooling water side of the Main Engine Cylinder head.

Q2. Tank liquid level sensors are an integral part of ships. Describe with aid of suitable sketches the working principle of,

(a) capacitive type level sensor;

(b) Ultrasonic level sensor;

(c) Float.

Q2. Cast iron is most widely used metal after steel in Marine Engineering. Most cast irons consist of graphite in steel like matrix. Discuss the variation of properties that may arise with reference to pearlitic grey cast iron and spherical grey cast iron. Describe briefly the treatment necessary to produce these two types of Irons.

Q5. Explain how the period of roll varies with –

A. The amplitude of roll;

B. The radius of gyration;

C. The initial metacentric height;

D. The location of masses in the ship.

Q4. Give a pragmatic approach to dealing with a sea water leakage, which is flooding the engine room and which has the potential of causing a serious impairment to a vessels stability.

Q7. Briefly describe your action plan on following exigencies:

A. Leaky economizer tube, while at sea;

B. Leaky intercooler of main air compressor, while manoeuvring.

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.

Q4. While operating at Sea during rough weather conditions, fire sparks have been observed coming out from the chimney. On investigation, it has been observed that the fuel contains considerable quantity of water and sludge. As the Second engineer of the vessel. Explain:
A. Immediate actions taken to rectify the problem.
B. Precautions you take to avoid recurrence of this type of problem.

Q3. With respect to the properties of fuel oil, explain the significance of the following terms.

(a) Calculated Carbon Aromaticity Inbox (CCAI).

(b) Open flash point and Closed flash point.

(c) The importance of Sodium to Vanadium Ratio.

(d) Octane Number.

Q3. Name various statutory Certificates and Documents to be carried on board Gas Tankers giving reference to the conventions and justify for their requirement.

Q1. Describe the relationship between frictional resistance and

(a) Ship’s speed;

(b) the wetted area;

(c) surface roughness;

(d) The length of the vessel.

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.

Q9. With respect to the operation of two stage reciprocating air compressor. Explain:

A. The causes of occasional lifting of 2nd stage relief valve.

B. Breakage of valve plates.

C. Puncture of bursting disc of 1st stage intercooler.

D. Noticeable reduction in capacity of the compressors over a period of time.

Q3. With reference to the main engine burning heavy fuel. Ship has been asked to use low Sulphur diesel oil, what are the problems likely to be encountered and risks involved in continuous running of main engine on such low Sulphur fuels.

Q9. With reference to Vacuum Sewage System

(a) Sketch & Describe a Vacuum Sewage System.

(b) State the advantages of Vacuum Sewage System.

(c) State the different causes of dropping vacuum.

Q2. If a ship is seriously damaged under water in way of a large fuel side bunker tank what is the immediate effect and what may ultimately happen? What features in the ship would enhance safety?

Q7. Which legislation is framed at preventing the emission of black smoke, sets the limits on the length of time of such emission?

A. Discuss the reasons for setting time limits rather than imposing a complete ban on emission

B. State why different times are quoted, giving examples.

C. State the likely constituents of black smoke from the combustion of residual fuel in a boiler.

D. List the contaminants likely to be found in the clear exhaust from a diesel driven alternate burning gas.

Q4. Explain the effect of reduced voltage on standard squirrel cage motors with respect to EACH of the following:

(i) Burn out; (ii) Starting current; (iii) Starting torque; (iv) Speed.

Q3. (a) With the aid of a simple sketch, explain the “trouble spots” in a basic air-conditioning unit and with reference to your sketch, explain the following: -

(a). How the problem of increase in humidity of cooled air is overcome?

(b). How discomfort caused by the excessive drying effect of heated air is overcome?

Q6. With Respect to main engine turbocharger;

A. Explain why cleanliness throughout the turbochargers system is critical to engine performance?

B. Describe in-service cleaning procedure for gas and air sides of a turbocharger indicating safety precautions to be observed?

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.

Q6. The following data applies to a ship operating on a particular voyage with a propeller of 6 m diameter having a pitch ratio of 0.95:

Propeller speed = 1.8 revs/s

Real slip = 34%

Apparent slip = 7%

Shaft power = 10000 kW

Specific fuel consumption = 0.22 kg/kW-hr

Calculate EACH of the following:

(a) The ship speed in knots;

(b) The Taylor wake fraction;

(c) The reduced speed at which the ship should travel in order to halve the voyage consumption;

(d) The voyage distance if the voyage takes 3 days longer at the reduced speed;

(e) The amount of fuel required for the voyage at the reduced speed.

Q5. With reference to an oil/water separator:

A. (i) Sketch such a device; (ii) Describe the passage of oil/water mixture from the delivery of pump to the outlets of separator.

B. State how oil density and temperature affect the case of separation of oil from water.

C. State how the movement of oil on board ship or its discharge and the discharge of oily-bilge ballast water overboard is recorded.

Q9. Abnormal vibration has been observed in an HFO purifier while in operation. Explain the areas you plan to investigate for rectifying the faults and put back the purifier back to normal operations keeping in view that no reduction in vibration has been noticed even after desludging the purifier couple of times.

Q6. A 72 KVA transformer supplies a heating and lighting load of 12 KW at unity power factor and a motor load of 70 kVA at 0.766 (lagging) power factor; Calculate the minimum rating of the power-factor improvement capacitors which must be connected in the circuit the ensure that the transformer does not become overloaded.

Q5. State the probable engine defects and rectifying action needed if the following conditions are indicated on a single unit of a large two-stroke marine diesel engine giving seven units. State any additional information which might be of help in forming on option.

A. Increased exhaust temperatures.    B. Reduced exhaust temperature.

C. Reduction in jacket cooling water return temperature.

D. Increase in jacket cooling water return temperature.

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.

Q7. A ship of length 120 m displaces 11750 tonne when floating in sea water of density 1025 kg/m3. The center of gravity is 2m above the center of buoyancy and the waterplane is defined by the following equidistant half-ordinates given in Table Q1:

Calculate EACH of the following:

(a) The area of the waterplane;

(b) The position of the centroid of the waterplane from midships;

(c) The second moment of area of the waterplane about a transverse axis through the centroid;

(d) The moment to change trim one centimeter (MCT1cm).

Q9. A. State the instructions you as Second Engineer will give to watch keepers with respect to boiler uptake fire;

B. State how the incidence of uptake fires may be minimized.

C. State the reasons for blow-back from the furnace of an auxiliary boiler.

D. State the standing instructions you might have received from your Chief Engineer With respect to the avoidance of boiler furnace blow-back.

Q7. A. Which of the following three motors has the poorest speed regulation: shunt motor, series Motor or cumulative compound motor? Explain.

B. A 440V shunt motor takes an armature current of 30A at 700 rev/min. The armature resistance is 0.7ohm. If the flux is suddenly reduced by 20 per cent, to what value will the armature current rise momentarily? Assuming unchanged resisting torque to motion, what will be the new steady values of speed and armature current? Sketch graphs showing armature current and speed as functions of time during the transition from initial to final, steady-state conditions.

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.

Q3. With reference to turbocharger bearings:

A. Discuss the relative advantages and disadvantages of white metal sleeve and ball race bearings for turbocharger rotor support.

B. State with reasons how axial location of the rotor is achieved.

C. Explain how the bearing are kept cool in service.

D. Indicate how the bearings are sealed from the atmosphere and exhaust gas.

Q1. As second engineer onboard a tanker, describe the procedure for presenting a Main Boiler for survey by a classification society?

Q8. A box shaped vessel is 80 m long, 12 m wide and floats at a draught of 4m.

A full width midships compartment 15 m long is bilged and this results in the draught increasing to 4.5 m. Calculate EACH of the following,

(a) The permeability of the compartment;

(b) The change in metacentric height due to bilging.

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.

Q8. Explain in detail how you would isolate one of sprinkler system for routine maintenance. Describe all tests and inspections you would make and how you would return the system to service.

Q8. A. What is back emf? Derive the relation for the back emf and the supplied voltage in terms of armature resistance.

B. A three- phase induction motor is wound for four poles and is supplied from a 50 Hz system. Calculate.

i. The synchronous speed; (4)

ii. The speed of the rotor when the slip is 4 per cent; (3)

iii. The rotor frequency when the speed of the rotor is 600 r/min. (2)

Q5. With respect to scavenge fires in Large two stroke Marine engines:

A. State the common causes of scavenge fires.

B. List the indication 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 in to service following a scavenge fire.

Q8. Detail the desirable properties of a refrigerant. Make a table and compare following refrigerants for use in a provision cooling plant for a 50000 DWT Oil tanker: R-22, R-134a.

Q8. A. What are the factors which determine the synchronous speed of a motor?

B. Three conductors fitted side by side in the stator of a salient-pole alternator. Each generates maximum voltage of 200V (sinusoidal). The angle subtended at the centre of the stator between adjacent conductors is 20 electrical degrees. If the three conductors are connected in series, find

(i) the r.m.s. value of the effective voltage and

(ii) the ‘breadth factor’. Using the theory that is the basis of this problem, give one reason why three-phase current has been introduced.

Q8. A ship 100 m long floats at a draught of 6 m and in this condition the immersed cross-sectional areas and water plane areas are as given below. The equivalent base area (Ab) is required because of the fineness of the bottom shell.

.

Calculate EACH of the following:

(a) The equivalent base area value Ab;

(b) The longitudinal position of the center of buoyancy from midships;

(c) The vertical position of the center of buoyancy above the base.

Q6. A. Explain the principles underlying the STCW Convention;

B. Explain how as a senior engineer you would implement the regulation for controlling and monitoring of minimum hours of rest for watch keepers;

C. What type of specific shipboard familiarization is required to be given to a seafarer new to a particular type of vessel?

Q9. Write short note on the followings –

A. Metal – locking;

B.TIG and MIG welding;

C. Brazing;

D. Soldering.

Q6. With reference to bridge control of a large slow speed propulsion engine.

A. How is starting and reversing achieved?

B. Investigate and suggest remedial action required if the engine,

(i) Fails to turn on air.

(ii) Turns on air but fails to fire on fuel;

(iii) Fails to reverse.

Q4. Sketch a sealing arrangement for an oil lubricated stern tube.

a) Identify the common forms of seal failure. (6)

b) State how oil loss due to seal failure can be restricted whilst on passage. (5)

c) What is the material used for sealing rings and propeller shaft liner? (5)

Q8. A ship 150 m in length, 24 m breadth, displaces 25000 tonne when floating at a draught of 9 m in sea water of density 1025 kg/m³. The ship’s propeller has a diameter of 5.8 m, a pitch ratio of 0.9 and a blade area ratio of 0.45. With the propeller operating at 2 rev/sec, the following results were recorded:

Apparent slip ratio = 0.06

Thrust power = 3800 kW

Propeller efficiency = 64%

The Taylor wake fraction is given by: WT = 0.5CB - 0.05

Calculate EACH of the following for the above condition:

(a) The ship’s speed

(b) The real slip ratio

(c) The thrust per unit area of blade surface

(d) The torque delivered to the propeller.

Q10. A. Compare the effectiveness of a current limiting circuit breaker with that of a HRC fuse.

B. A coil having a resistance of 10 Ohm, and an inductance of 0.15 H is connected in series with a capacitor across a 100V, 50Hz supply. If the current and the voltage are in phase what will be the value of the current in the circuit and the voltage drop across the coil?