QUESTION BANK MARINE ENGINEERING PRACTICE PART-2

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1854

Q An A/E shows 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 the hunting.

b) Explain how the problem of hunting can be corrected.

Q a) As 2/E, outline your instructions to members of the ship’s engineering staff for inspection of the main engine timing chain.

b) The inspection in (a) has shows that the roller chain needs replacement. Describe how this is achieved.

Q Severe engine vibration has recently become evident when the M/E for which you are responsible operates within a certain speed range.

a) State, with reasons, the possible causes of such vibration.

b) State the significance of operating the engine under such vibratory conditions.

c) Describe the process you, as 2/E, would carry out in order to investigate and rectify the problem.

Q Describe 3 ways in which each of the following defects would reveal itself during full power operation of an engine.

a) Cracked liner

b) Defective fuel valve

c) Overheated bottom end bending

d) Inefficient turbocharger

Q Discuss the validity of each of the following statements with respect to large slow speed diesel engines:

a) Bearing clearances taken 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 the deflections.

c) A timing chain should be renewed when its slackness causes late fuel injection & exhaust valve operation.

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

Q In operation of a 2 stroke engine following conditions were observed. A gradual rose in the exhaust temperature at one cylinder. A lies in crank case sump level Explain the reasons & subsequent action taken for the same.

Q With reference to medium speed diesel engines explain how a chief engineer officer would direct staff to carry out each of the following:

a) Check engine performance during operation

b) Establish the condition of the lubricating oil

c) Monitor the general condition of the engine during the voyage

Q Sketch & describe a system of control for manoeuvring a main diesel engine from the bridge & show local control may be affected in case of the breakdown of the system.

Q Describe the hull inspection that you would carry out as the senior engineer of a ship in drydock stating

what defects you may find & the repairs that may be necessary with respect to:

a) Shell plating

b) Ford end of ship

c) Aft end of ship

d) Openings in shell plating

e) Rudder

f) Propeller and stern tube

Q Your ship after having been accidentally grounded was taken to dry dock for inspection and necessary repairs. What defects would you look for in the following parts that may have sustained damage due to grounding and suggest method of repair that may be required to be carried out to the defects noticed:-

a) Propeller shaft and tail end shaft

b) Main engine crankshaft

Q With reference to drydock of sea going vessel, describe the following:-

a) Precautions to be taken while the vessel is in drydock

b) Checks to be done prior undocking

c) Precautions to be avoided fire in the engine room during the drydock

Q Define the responsibilities of a 2/E in respect of the following:

a) Immediately prior to dry docking.

b) Whist the dock is dry.

c) Immediately prior to and after flooding.

d) Leaving dry dock.

Draft a list of the standing orders to the engine department for that period that the vessel is on the blocks.

Q Your ship after having been accidentally grounded was taken to a drydock for inspection & important repairs. What defects would you look for in the following parts, that may have sustained damage due to the grounding & suggest methods of repairs that may be needed to be carried out to the defects noticed.

Q Your ship is in the drydock prepare repair specification for the following:

a) Main cooling seawater overboard valve.

b) Aft winch hydraulic oil pressure line holed at deck

c) Penetration in the steering compartment

d) Deck seal of the IG system in an oil tanker

Q a) With reference to the insulation testing of the marine electrical plant:

i. State the reasons for insulation testing

ii. State the precautions to be noticed when testing intrinsically safe equipment Type Ex.i.

b) Describe the overhaul of the D.C. motor which has been subjected to excessively damp condition or flooding with the seawater.

Q With reference to the circuit breaker for an A.C. generator:

a) Explain the sequence of the events that might occur if the breaker opens on a short circuit & state the check you would require following such event.

b) Give a safe process to follow should a main circuit breaker fail to open under fault condition.

Q a) Describe the preventive maintenance done on the circuit breaker for an a.c. generator.

b) Explain the sequence of the events that might occur if the breaker opens on a short circuit & state the check you would require following such event.

c) Give a safe procedure to follow should a main circuit breaker fail to open under the fault condition.

Q State how safety is achieved with regard to the gas emission in battery rooms where a large number of the lead acid cells are stored with reference to:

a) Provision of lighting

b) Ventilation if a fan is fitted

c) Type of the distilled water container for topping up

d) Use of tools & replacement of defective batteries

Q What are the routine maintenance done out to an a.c. motor and

a) Explain the meaning of single phasing in the a.c. machinery.

b) State the dangers associated with single phasing & enumerate the protective normally installed to counteract such dangers.

Q a) A ship operating in the U.M.S mode must have an automatic fire detection system for the machinery space.

b) Sketch a line diagram of the system showing how shipboard mains supply is fed to the battery charger & emergency battery to fire detector heads & fire zone indicator panel and alarms

c) In the event of a mains supply failure state the length of the time for which the emergency battery should be capable of operating the system.

d) Sketch & describe a method of monitoring the integrity of the system.

Q With reference to the hull cathodic protection systems of the impressed current type:

a) Sketch & describe such a system

b) Explain how protection may be ensured for the rudder & propeller.

c) State any precautions that should be taken when this type of system is fitted.

Q A cage rotor induction motor has been flooded with the seawater. Insulation resistance is down to 0 MΩ. Describe the procedure for putting the motor back into  the service?

Q Describe the procedure to be followed when, upon a routine schedule for changing fuel injectors on a main engine, it is found that the injector body is seized & cannot be removed by the conventional means. How to ascertain whether the cylinder head & injector can be used satisfactorily?

Q a) State the circumstances owing to which it may be required to renew the cylinder liner.

b) Explain how the liner is removed.

c) Explain how a new liner is fitted.

State the important checks to be made before & after fitting

Q 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 engine if it is allowed to operate with the slack tie rods.

c) Explain how this problem can be reduced.

Q What factors would you consider in deciding whether to open up a cylinder unit for overhaul? After opening the unit & preparing for assembly, how would you decide whether to renew the piston rings?

Q A completely new unit comprising piston, rings, liners, cylinder head & valves was installed to the 6-cylinder single acting 4-stroke diesel generator. Before installing the clearance & sizes were checked & considered satisfactory. During a trial run the running characteristics were abnormal so the generator was stopped. On examination it was seen that the new piston had badly scored & drubbed the liner & had indication of seizure in the upper part of the liner. Give your reasoned comments for the failure.

Q Fuel injector needle valves are found to be seizing frequently. Explain:

a) How could such seizures can be detected, and,

b) Preventive measures & remedial actions that can be taken.

Q With reference to the cylinder valves, state how the following faults become apparent:

a) Slackness of air inlet & exhaust valve spindles in their guides.

b) Leaking starting air valve.

c) Late opening of the air inlet valve.

d) State how each fault is corrected, & suggest how they could be avoided.

Q As 2/E describe the process involved in the complete inspection of a cylinder liner & piston assembly, indicating areas of significant interest.

a) Explain with reasons, possible faults which might be found.

b) Suggest how such faults might be corrected.

Q Recent experience has shown persistence damage occurring on the seating faces of M/E exhaust valve, which is not confined to any particular cylinder unit.

a) State with the reason the possible cause, the possible cause.

b) State the short term actin to be taken in order to minimize engine operational problems.

c) State, with reasons, how future incidents of this nature could be minimized.

Q Consider an engine installed with a chain driven camshaft,

a) What effect has the stretching of the chain upon engine performance & maintenance?

b) How is the chain tension adjusted to its initial value after stretching?

c) How is the engine timing collected post adjusting the chain?

d) What is the most common cause of the chain failure & what part of the chain is most prone to this failure?

Q a) A 4-stroke diesel engine has a leaky fuel valve. Describe the symptoms you would look for, for confirming the same.

b) Explain the dangers involved & the action you would take to continue the safe operations of the engine.

Q Due to wiping main engine bearing needs emergency repairs. Describe how the repair to the bearings may be done. How the repaired bearings would be fitted?

Q Main engine de-carbonization was carried out on piston inspection the following faults were observed:

a) Cracking & burning of upper part of crown.

b) Cracking in the piston ring groove.

c) Explain the cause & how it can be minimized.

Q With regard to the main turbine lubricating oil system:

a) i. Describe the effects of tin oxide corrosion.

ii. Explain the actions to be taken if this occurs in the high pressure turbine thrust bearing.

b) Discuss the factors that determine the various filtration sizes.

Q Give a list of the properties or tests by which distillate & blended fuels may be specified or decisions be made on their fitness for the use. Name the properties or constituents that may be found in the blended fuel having a high viscosity & high carbon content, explain how they may cause problems in the engine operation.

Q With reference to the hydraulic cargo handling system

a) State 4 possible cause of the contamination of oil

b) State 4 possible effect of the oil contamination on the system & remedial measures

c) State how the system oil may be monitored for the contamination.

Q Although your vessel is engaged upon regular trade you notice that the specific fuel consumption has noticeable increased whilst the average speed has decreased in comparison to the previous speed. What investigation will you make &  based on your finding what collective measures would you take?

Q The off-specifications fuel has been received on board. In the absence of the low R.O.B of old fuel. Explain with reasons what actions should be taken to minimize damage & enable safe operation of the engine, if following fuel properties were above specified levels:

a) Ignition quality

b) Conradson carbon level

c) Viscosity

d) Specific gravity