GENERAL
BOILER
1. A rating has been badly burnt by a “blow back” from the oil fired auxiliary boiler. As second engineer, make a full report to head office explaining the
circumstances of the incident and the precautionary means now taken to reduce the possibility of a similar occurrence in the future.[8/07], [3/07],[6/05],
[1/05], [8/08], [8/09], [2/10], [06/11Em],
2.Describe how the following conditions can be avoided in auxiliary boilers:
a. Furnace distortion
b. Uptake fire
c. Difficulty in maintaining normal water level.[8/07], [1/05], [12/09], [1/10], [06/11Em], [3/08 MEP],
d. High boiler water density. [3/08MEP], [Em07-08],
3. 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 has requested you to re-commission the boiler. Write a letter to the superintendent engineer stating how the boiler was brought on line and the safety valves adjusted. [7/07](mep22), [9/05], [8/04], [6/08], [7/09], [11/09],
4. a. Discuss the possible reasons for the following changes in boiler water results, and state what actions should be taken each case:
i. Reduction in total dissolved solids and chemical reserves.
ii. Reduction in phosphate reserve, with increase in chlorides and total dissolved solids.
iii. Reduction in alkalinity reserve only.
iv. Increase in oxygen levels only.
b. State why the complete results of boiler tests are logged or entered into a data retrieval system rather than a note being made of any particular result
which may be out side set limits. [7/07], [2/06], [3/08], [6/09], [9/09], [Em10-11], [11/10], [06/11Em],
6. 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. [3/09], [6/09], [Em10-11], [11/10]
b. Describe the procedure for the setting of safety valves of exhaust gas fired auxiliary boilers.
c. Explain the action(*a chief engineer should) taken after the setting of safety valves as in (b).[5/07],[6*/06],[2*/06], [2/05],[9/07], [9/08]
7. A fire in the exhaust gas boiler on a motor ship may develop in two or three stages. With reference to such situations, discuss:
a. The factors which could be a cause for initiation and development of: [4/07], [4/06], [1/06], [4/08],
i. Ignition of soot;
ii. Small soot fires;
iii. High temperature fires.
b. State the standing instructions you, as second engineer officer, would issue with respect to the action to be taken in the event of a boiler uptake fire.
9. a. Describe three different patterns of the tube used in exhaust gas boilers.(mep15)
b. Give two reasons why a tube is condemned.(mep15)
c. How would a leaking tube to be rectified?
d. How can the operating efficiency of an exhaust gas boiler be maintained at an acceptable level? [3/07], [3/06],[6/04],[2/08],
10. Sketch and describe a boiler water level controller of the float operated type. State the reasons for having this mechanism on the boiler and using the
controller and boiler for analogy explain the following terms.
a. Detecting element; b. Servo motor; c. Desired value. [2/07],[10/08], [12/09],
14.An auxiliary boiler water level control system has a differential pressure transmitter as the detecting element for water level.[Em06/07], [1/08],
a. Sketch and describe such an arrangement.[11/08], [12/08], [1/09],[Em10-11],
b. If the transmitter was damaged describe how a replacement unit would be calibrated. [9/06](mep16),[8/06], [Em05/06], [7/05], [11/05],[9/04],
16. a. Draw a line diagram of a feed water system for an auxiliary boiler, labeling all the principal items and showing the direction of flow.
b. Explain how feed supply to the boiler is regulated? Explain rising water level characteristics of level control.
c. State what preventive and corrective measures may be taken if oil contamination of the feed water takes place? [7/06],[10/07], [Em08-09]
17. Describe how you as second engineer, would prepare an auxiliary boiler for survey by a classification society. [6/06],[2/06], [8/08] , [7/09], [11/09],
[11/10],[3/11],
18. Sketch a high lift safety valve lid and seat detailing their special features. Describe how such a valve is overhauled and any clearances that should be
measured and noted. [5/06],[4/05], [1/10], [3/10], [4/10], [2/11],
20.Give reasons why even moderately rated auxiliary boilers require regular attention to both feed and boiler water condition. Suggest with reasons the
possible consequences if this attention is neglected. [3/06],[Em07-08],
21. With respect to auxiliary boiler water level maintenance and indication, describe, with the aid of sketches, the sensing devices for:
i. A feed pump control; ii. Local water level; iii. Remote water level; iv. Low and high water level alarms. [Em05/06], [6/05], [1/08],[11/08]
25. You have been appointed as the second engineer of a fifteen years old bulk carrier, recently purchased by your shipping company. Exhaust and auxiliary
boilers, are due for survey and requires extensive repairs. Write a report to the engineering superintendent with respect to the inspection carried out and the
defects observed. Also give details of repairs to be carried out for the safe operation of the boilers. [7/05], [10/07], [3/09],
27. With reference to auxiliary boiler safety valves:
a. Describe with aid of sketch the safety valves for an auxiliary boiler.
b. Identify with reasons the parts that require particularly close attention during overhaul;
c. Describe how the safety valves are reset after an overhaul. [5/05], [3/08], [2/09], [12/09], [4/09 MEP],
33. Describe how you would test boiler water for :a) Alkalinity b) Chlorides [12/10], [12/10MEP],
i. Dissolved salts; ii. Undissolved
State the values obtained from the tests that would be considered suitable for a water tube boiler. If the test results were satisfactory what remedial action would you take? [3/04],
34. Describe the method of setting the safety valves of an exhaust gas boiler at sea.
a. State the limit in terms of percentage above maximum design working pressure, for setting safety valves.
b. State the formality necessary when the chief engineer sets the safety valves. [Em03/04](mep19), [9/10,6/11]
35. With reference to pneumatic differential transmitters;[1/08], [Em07-08], [11/08], [8/09/10]
a. Sketch and describe such a transmitter;b. State the duties that they may perform.
36. With reference to feed regulation: [3/11]
a. Describe, with the aid of sketches, the operation of a boiler feed water regulator controlled by at least two other parameters besides water level in the
drum;
b. Give reasons for inclusion of the other elements besides water level, in controlling feed flow;
c. Deduce the possible effects on the system when the drain valve on the constant head leg in the level transmitter starts to leak.
PUMPS
1. a. Explain why centrifugal pumps cannot handle air or vapour to effect priming yet turbo blowers operating on the same principle can.
b. If 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 method of priming suitable for a centrifugal pump.[2/07], [8/06], [2/05], [2/04], [9/07], [9/08], [10/08], [9/09], [Em08-09]
3. a. i. Sketch the pump characteristics of a typical centrifugal pump.
ii. Explain how these characteristics are obtained.
b. Some engine rooms circulating pumps of the centrifugal type are arranged for variable speed operation. Sketch the characteristics curves for such a
pump indicating the effect of varying speed.
c. State the reasons for using pumps of the type referred to in (b). [7/06], [10/07], [12/08], [1/09],
4. a. Sketch a simple cross section through a single stage centrifugal pump with a fully shrouded single entry impeller, name the components of the pump
and indicate the direction of fluid flow.
b. i. The function of the impeller and how suction is created by it.
ii. The function of the volute casing.
iii. State the material of each component of the pump.
c. State the suction lift that may be expected.
d. State why some centrifugal pumps have:-
i. A double volute casing.
ii. A diffuser ring. [5/06], [1/10],
5. a. Sketch and describe a gear type pump indicating the flow of fluid.
b. State the materials that gear type pump components may be manufactured from.
c. Specify three applications that are suitable for the employment of gear type pumps. [11/05], [Em10-11],
7. Ships are provide with an independent diesel or an electric or an air operated emergency fire pump.[Em07-08],[7/09/10]
a. State, with reasons, the areas in which emergency fire pumps are commonly installed
b. Describe with the aid of a sketch an air pump or primer used to initiate suction when the fire pump is situated above seawater level.
c. State the jet output capacity that the fire pump must be capable of
d. State how it can be ensured that the fire pump is kept in good working order.
e. State the precautions that must be taken in sub zero temperatures.
FRESH WATER GENERATOR
1. Reverse osmosis is the modern alternative 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. [2/07], [2/04], [10/08] ,[9/09], [7/09/10]
2. a. Draw a line sketch of a system used as an alternative to low pressure evaporator for producing water on board ship?
b. Explain its working principle.
c. What are its inherent advantages and limitations? [7/06], [12/08] , [1/09],
3. a. Sketch and describe a low pressure evaporator utilizing low grade heat to produce the distillate.[8/09/10]
b. State with reasons the prohibitions placed on the use of the evaporator with regard to the location of the vessel.
OILY WATER SEPERATOR AND SEWAGE SYSTEM
1. With reference to oil/water separators:-[10/07], [3/10], [4/10],[3/11]
a. Describe with the aid of a sketch, the working of such a separator.
b. Explain the consequence if the interface detector position is incorrect. [1/04],
c. Enumerate the various possibilities by which oil/water interface can be described.[4/05], [8/04],
d. Describe with the aid of a sketch, the circuit for an interface detector. [1/04],
3. a) i) describe with the aid of a sketch an aerobic sewage treatment plant [8/09/10]
ii) State the effect, if any, of change of temperature and flow on the system
b) explain the significance of biological oxygen demand
AIR COMPRESSOR AND RESERVOIR
1. Give a reason why each of the following features is considered desirable in air compressors:
a. Smooth air passages with minimum obstruction at valves,
b. Minimum clearance volume,
c. Multitubular heat exchangers,
d. Generous size of suction filter.[8/07], [6/05], [1/05], [8/09], [2/10], [06/11Em],
3. a. Explain why it is essential to ensure adequate cooling of air compressor cylinders, inter coolers and after coolers.[2/10],
b. State with reasons the possible consequences of prolonged operation of the compressor if these areas are not adequately cooled. [4/07], [5/06],
4.Describe the term volumetric efficiency as related to air compressors. Describe the effects of following faults in multi stage reciprocating air compressors:
a. Inter stage cooler starved of cooling water;
b. Worn crankshaft bearings;
c. Broken or worn scraper rings;
Suggest a fail safe arrangement in the event of inter stage cooler water loss.[1/07], [6/06], [2/06], [8/08] , [7/09], [11/09], [11/10]
5.Sketch a reciprocating air compressor incorporating a first stage rotary compressor. Explain the motive behind such an arrangement. State with reasons
whether the advantages claimed for this design justify the added complexity. [4/06], [3/08], [8/09],
8. a. Define the considerations governing main air receiver capacity.
b. Give reasons why the internal surface of an air receivers are frequently coated with clear copal varnish.
c. Explain why air receiver drain valves should be overhauled at every available opportunity. [Em05/06], [11/05], [1/08], [11/08]
9. With reference to main air compressor
a. Describe the method of control used when a compressor is running continuously.
b. Describe the principle of operation of automatic drains fitted to air compressor.
c. Describe the effect of leaking suction and delivery valves in an air compressor. [7/05], [Em08-09]
10. With reference to reciprocating air compressors explain why:
a. Clearance volume is critical to efficiency.
b. Spring-loaded plate valves are invariably used.
c. Compression is accomplished in apparently unequal stages.
d. Inter-cooling is used between stages. [5/05], [4/08], [7/09], [11/09],
12. a. Discuss the possible problems associated with air compressors which operate automatically.
b. State the standing orders you, as second engineer, would issue regarding the maintenance and safe and efficient operation of air compressors.
c. Outline any problems common to air receivers and machinery space/ ship compressed air system
AIR CONDITIONING AND REFRIGERATION
1. a. For Freon-22 vapor compression refrigeration machine, state how each of the following faults are indicated and how they are remedied;
i. Air in the system;ii. Moisture in the system;iii.Undercharge;iv. Overcharge.[7/06], [6/07], [4/06], [9/04], [3/09], [8/09],
b. Describe with a diagram detailing the devices incorporated into the refrigeration system to protect the machinery and equipment against malfunction.
2 a.Sketch a ship’s indirect refrigeration system arranged for cooling containers stowed in stacks in the hold.[Em06/07], [2/10],
b. Describe the refrigeration system sketched in (a)
c.State the advantages of the system described in (a)compared with containers with their own refrigeration self contained units.[4/07], [5/06],
5. a. Sketch and describe a high pressure cut out in a refrigeration system.[3/09], [Em10-11],
b. The refrigeration compressor has stopped due to operation of the h. p. cut-out. Explain :-
i. The possible causes.[Em03/04],
ii. How these causes would be found and possible remedies.
What steps are taken if the compressor short-cycle on low pressure cut-out. [Em06/07], [8/06], [1/06], [2/05], [9/07],[9/08]
9. a. Draw a block diagram for a fully automated accommodation air conditioning unit, labeling the component parts and indicating the directions of air
flow. [3/05], [3/09],
b. Explain why the unit includes means of dehumidification and humidification.[7/05],
c. A chart is used for ensuring the accommodation conditions are within the so called comfort zone what useful information does the chart give.
12. With reference to air conditioning units[11/08],[8/09/10]
a. With the aid of a sketch, explain the operation of a unit which includes means of dehumidifying, humidifying and refrigerated cooling.
b. i. Describe the conditions that could lead to legionella growth.
ii. List the precautions necessary in the maintenance of air conditioning systems to reduce the risk of legionnaries disease being contacted.
13. a. Sketch and describe the purpose of an expansion valve as fitted in a refrigeration system;
b. With reference to a high pressure cut out in a refrigeration system, state four operational circumstances that may cause a high pressure cut out to
operate. [1/08], [11/08] ,[8/09/10]
14. i) Describe an air conditioning system for a passenger car ferry.[1/11],
ii) Explain in detail how the humidity of the air is measured and controlled.
STEERING GEAR
1. a. Sketch a four-ram steering gear arrangement capable of 100% redundancy.[2/08], [3/09], [3/10], [4/10], [06/11Em],
b. Describe the operation of the arrangement sketched in (a).[8/07],[4/07], [Em 6/07], [7/06], [5/06], [1/05], [8/08]
b. Describe the operation of the arrangement sketched in (a) when the working pump oil manifold develops a serious leak.[2/08],
2. a. Describe with the aid of sketches where necessary a rotary vane type steering gear showing how the weight of the rudder and stock are carried and
thearrangement that allow for wear down.[8/06], [2/05], [9/07], [10/07],[6/08], [9/08] ,[3/09], [7/09], [11/09], [2/10], [Em10-11], [Em08-09]
b. State how the vanes described in (a)are secured and the method of sealing the edges.
c. State how, if necessary the steering gear is locked for rudder maintenance.[7/07], [8/04],
d. State what considerations determine the number of vanes. [7/05],[4/05],
3. With reference to electro hydraulic steering gears:[2/09], [9/09], [4/10], [7/09/10], [11/10]
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.[5/07], [9/06], [6/06], [2/06], [10/04],
5. a. Draw a diagram of a four ram electro-hydraulic steering gear showing:
i. Pump isolating valves;ii. Relief/shock valves;iii. Bypass valves.
b. Explain the operation of the system sketched in (a).
c. Indicate in the diagram in (a) the valve positions for the operation of the system when one pump is isolated and the unit is operating on two rams
only. [4/06], [4/08], [3/11]
7. With reference to a four ram hydraulic gear, having duplicate pumps:[Em05/06], [11/05], [1/08],[11/08]
a. Sketch the arrangements of relief, make up, isolating and by-pass valves.
b. Explain the use of isolating and by-pass valves, if one of the cylinders has fractured.
c. Describe the arrangement provided to indicate the loss of hydraulic fluid due to leakage.
10. With reference to hydraulic steering gears:[10/05], [6/08], [6/09],
a. Briefly define each of the following:
i. Single failure concept; ii. 100% redundancy.
b. Sketch a line diagram of the actuators and their associated hydraulic system for a hydraulic steering gear capable of 100% redundancy.
15. a. Sketch and describe a four ram hydraulic steering gear system;[Em07-08], [8/09/10]
b. Explain the operations that are necessary to enable a four ram system to operate on two rams only.{see Qno 1}
PROPELLER SHAFTING AND DRY-DOCK
1. a. State why fixed pitch propellers have a poor efficiency when going astern.[8/07],[6/05], [5/05], [1/05], [6/08], [8/08], [6/09], [06/11Em],
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.
2.Describe the possible faults which may be found during a dry dock inspection of the following:
a. Stern frameb. Sea chest c. Bilge keel d. Anodes e. Rudders[7/07], [4/05], [Em05/06], [8/04], [4/08], [2/09], [3/10],[4/10],
3. With reference to sleeved keyless propeller assemblies:[9/07], [9/08], [12/08], [1/09], [2/10],
a. i. State with reasons the metals used in the manufacture of the sleeve and tail end shaft;
ii.State the type and thickness of material used to bond the sleeve to the propeller boss.
b. When removing the propeller from the tail end shaft, state why the following procedures are not recommended:[3*/07],[6/04],
i. Application of push off force by means of wedges or jacks and draw off force by strong back;
ii. Expansion of propeller boss by concentrated local heating with gas torches.[2/05],
c. State the correct procedure for removal of the propeller from the tail end shaft.[4/07],[3*/07], [5/06],[6/04],
4.A rudder of a vessel requires extensive welding repairs and as second engineer you are requested to supervise
a. Suggest a suitable type of welding process
b. State with reasons 4 common welding defects.
c. State what tests may be carried out before returning the rudder to service. [3/07],[2/07], [6/04],[2/04], [2/08], [10/08], [8/09],