Questions encountered in August 2014 - Thanks IK
A visitor reported that the following questions showed up on his exam in June 2007...
G01. Care of an air compressor either 2 or 3 stage. What attention is needed before opening up for inspection?
G02. What faults are likely
to develop in an air compressor and how are they remedied.
G03. 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 2400 kPa compressor and state materials used.
G04. Describe the
construction of a 3 stage air compressor
give the temperatures and pressures at each stage
where are the drains
what type of oil is used and why
G05. Describe a 3 stage air compressor. Why is there a cooling system. Sketch a cooler suitable for 2400 kPa
G06. Why are isothermal conditions desirable in an air compressor and adiabatic conditions in a diesel engine? How are these conditions aided? What physical properties prevent these conditions from being perfect?
G07. Draw a combined
indicator diagram of a 3 stage air compressor, and show the effects of
intercooling. Give the
various pressures and temperatures.
G08. How is the efficiency
of an air compressor affected by the following:
excessive clearance volume
insufficient cooling water
restricted low pressure air supply
Shafting, Stern Tube and Bearings
G09. 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?
G10. Make a detailed sketch
of the sealing arrangements for an oil-filled stern tube. Describe the common forms of seal failure.
Explain how oil loss due to seal failure is restricted whilst on
passage. Describe how the
seals are restored to their original effectiveness. Give a reason other than the expense of oil loss why effective sealing is necessary.
G11. Compare the merits and
demerits of roller and plain bearings when used for main shafting. Describe with sketches a roller bearing for main shafting.
Explain why the need to split main roller bearings creates problems
and how they are overcome. Give
two reasons why roller bearings are rarely employed as stern bearings.
G12. Sketch and describe a
main bearing as fitted to a diesel engine. How would it be remetalled on board ship in an emergency?
G13. Identify the chief
causes of overheating in tunnel bearings and of vibration in main
shafting. Explain why the
siting of the engine room amidships enhances these tendencies. State how overheating and vibration may be reduced or eliminated.
G14. Give two reasons for
sludge formation in main lubricating oil systems. Explain how bearing metal is attacked with particular reference to
incompatibility between the oil and metal. Explain the role of additives and state what normal practices must
be suspended in order to maintain treated oils in their optimum condition.
Discuss the problems associated with the use of a multi-purpose
G15. By examining bearings, give the condition of lubricating oil in an engine. State simple tests that may be performed aboard ship. How would you keep lube oil in good condition.
G16. With reference to main
shaft bearings which are excessively loaded or very lightly loaded state
for each condition what are the:
indications of the fault
effects on adjacent bearings
Explain why load distribution on main shaft bearings changes in service.
G17. Discuss the merits and
demerits of shell and pad shaft bearings. How is shafting alignment checked with What is the effect of
tailshaft weardown on the adjacent shaft bearings.
G18. How is the weardown of
a tail shaft checked? How
often is it taken? Where
would you find previous readings? What
maximum weardown would you allow for a 250 mm diameter shaft?
G19. Describe the procedure
in lining up an engine bedplate, main bearings, gear box, thrust block,
propeller shafting and tail-end shaft, assuming this to be a new ship.
G20. With reference to shell
and pad bearings which are excessively loaded or very lightly loaded state
for each condition what are the:
indications of the fault
effects on adjacent bearings
Explain why load distribution on bearings changes in service.
G21. Sketch and describe a
single collar thrust block. How
is lubrication effected? What
pressure can be carried as compared with a multi-collar thrust?
G22. Give a reasoned opinion as to the accuracy of
the following statements:
the effectiveness on a main thrust block is only as good as its
pivoted pads are not necessary in thrust bearing design
fore and aft clearance between shaft collar and pads is of little
G23. How is the position of
the engine fixed in a ship? How
is the engine aligned? How is
the engine secured to floors or tanktop. (sketch method). What is a crankshaft deflection and how is it done.
G24. What is the purpose of a cofferdam. Where are they located? Name all their fittings. How are they entered?
REF:JAN87 REF: 90
G25. Sketch and describe a diesel electric propulsion system. Mention disadvantages and advantages.
G26. Describe 4 types of
stress. Give an example of
each in a boiler and an engine.
G27. Regarding air receivers
and boilers, what is the nature and intent of stresses in the longitudinal
and circumferential seams. State
the rules that apply.
G28. Explain fatigue and
thermal stresses. State 2
examples of each an encountered on a diesel ship. How are they dealt with.
2 examples of each.
G29. Sketch and describe a
stockless anchor illustrating the method or device used to attach it to
the chain cable. When the
anchor and cable are ranged during the ships underwater survey what parts
require special attention and what defects are likely to be discovered?
G30. Describe and sketch an
axial flow pump. Explain it's
principle of operation. State
what important advantage and serious disadvantage it possesses compared to
other pumps. Explain the effects of throttling either the suction or
G31. Describe the auxiliary
machinery that would be required for safe and efficient operation of a
large motor ship. Describe the size and capacity of the pumps. State the type
Fuel & Combustion
G32. What are the conditions
required in the cylinders of a marine diesel engine for good combustion.
Under normal working conditions the following may occur:
What may be the suspected cause for each case to occur?
What would be the remedy for it?
G33. What is meant by the term "closed flashpoint" of an oil? Describe a test to determine its value. State any factors that limit the temperature of heating for marine fuels. Give the approximate closed flashpoint of:
boiler fuel oil
34. What is the chemical
composition of coal? Give the
G35. Give the calorific
values of anthracite and bituminous coals. What are the chemical compositions of this coal?
G36. Discuss any form of the
G37. What is meant by the
"flash point of oil? How
is it obtained? What are the
approximate closed flash points of the following fuels:
Heat Exchangers and Coolers
G38. With reference to a
tubular heat exchanger:
why is ferrous sulphide being used in place of impressed
where are TEFLON inserts being used
what type of material is used for the tubes
G39. With reference to
multitubular heat exchangers explain:
how and where impingement attack is likely to occur in the tubes
Why is it desirable that coolant flow rate should not exceed that
required to maintain correct fluid temperature
ample well-shaped water boxes and smooth tube inlets are desirable
partial obstruction of tube bore is a common cause of tube failure
G40. With reference to
tubular heat exchangers explain:
how differential movement tubes and body is accommodated when the tube
plates are rigidly located in the body
how and why turbulence is imparted to fluid flow through the tubes
why it has become possible to discard sacrificial anodes in sea water
what is meant by the term 'guided flow', with particular reference to
G41. Considering erosion
and corrosion in a heat exchanger system give the effects of :
welding and brazing
G42. Sketch and describe a
plate type cooler. Explain
how leakage is prevented. State
one advantage and one disadvantage it possesses over the tubular type.
G43. With reference to heat
exchangers define what is meant by the terms 'parallel flow' and 'contra
flow'. Give two advantages
and two disadvantages of each type of flow. State an application for which each is most suitable.
Describe how the 'fall off' in efficiency of heat exchangers may be
G44. Discuss the different
type of coolers:
Sketch and describe how constant salt?? water temperature is maintained
in a system.
G45. Discuss recent
developments in the protection of the hull from the effects of corrosion.
Discuss the advantages and disadvantages of various types of hull
indicating your position with respect to the merits or demerits of
cleaning the hull while the vessel is afloat.
G46. Discuss the merits and
demerits of employing either a soluble oil or a chromate solution as a
corrosion inhibitor in the cooling system of a diesel engine.
G47. Describe any method of
boiler feed treatment you are familiar with. What chemicals are used, and how is scale prevented?
G48. Describe how you would
test boiler water for:
State the values obtained from the tests that would be considered
suitable for a water tube boiler. If
the test results were unsatisfactory, what remedial action would you take?
G49. Give composition of
boiler scale. If you had to
use seawater in the boiler, explain what steps would be required to
maintain a reasonable level of impurities. What level of impurities would you try to maintain?
G50. What is caustic embrittlement?
G51. What is a salinomitor?
Instruments and Gauges
G52. Sketch and describe a thermo-couple pyrometer. Where are thermocouple pyrometers fitted on steam and motor ships?
G53. Describe, with the aid of a sketch, a device used to measure the depth of oil in a tank. The instrument in the question may be used without opening the tank. Does the specific gravity of the oil have any effect on the reading of this gauge.
G54. What gas would be found in the following compartments and how could their effects be minimized?
empty ballast tank
paint store room
G55. State what is the
purpose of each of the following items in a machinery control system:
portable mercury manometer
portable inclined-tube manometer
portable temperature potentiometer
compressor and vacuum pump
Describe in detail any two of these items.
G56. Using a cathode ray
oscilloscope for obtaining indicator diagrams from main engines describe
and state the manner in which it may be used to illustrate certain
important features, such as combustion process etc.
G57. Describe 2 different
types of pressure gauges that work by an elastic system. Give an example of what each is used for.
Explain how one of these is calibrated.
G58. Sketch and describe:
a torsion meter
G59. Describe a torsion
meter and show how it is used to find shaft horse power.
G60. Describe a dynamometer
as used to find brake horse power of
an engine. After determining
the B.H.P. how would you find the mechanical efficiency?
G61. Regarding remote
control sensing devices of either electrical or pneumatic type, name two
advantages and two disadvantages of each. Which device would be used for:
lube oil pressure
tank level indicators.
What precautions are taken in hazardous areas?
G62. Sketch and describe a
fuel meter used with high viscosity fuel. Explain how it operates.
the value of the readings obtained and how they are used.
G63. Sketch and describe an electro/hydraulic steering system. How is emergency steering carried out?
G64. With reference to ram
type electro-hydraulic steering gears explain:
why four rams are provided in many instances
with sketches the arrangement of the crosshead rapson slide and its
principle of operation
why the telemotor receiver is spring loaded and the effect on steering
of spring failure
G65. Examine in detail three
common but entirely different reasons for loss of steering. State how failure is inhibited in the design, operation and
maintenance of steering gear systems. Describe how a vessel may make port upon irreparable failure of the
G66. Describe how you would remove air from a telemotor system. What are the dangers of air in a telemotor system?
G67. Explain how the
following steering gear faults are corrected:
persistent overloading of pump motor
purge system of air
G68. How is the vertical
movement restricted on a rudder and how is it accommodated in the steering
gear? How is the weight of
the rudder transferred to the ship?
G69. Sketch and describe an
electro-hydraulic steering geas as fitted on board ship and indicate
emergency steering methods. How
is the weight of rudder supported?
G70. Fully describe a
steering gear you are familiar with. How are shock loads prevented?
Explain hunting gear.
G71. Describe fully any type
of hydraulic steering gear with which you are familiar. Explain its operation and how it's movements are controlled
from the bridge.
G72. What provision is made to avoid damage to steering engines when they aare situated adjacent to the rudder stock? Describe a steering system showing how it is controlled from the bridge. What is the hunting gear? Describe its action.
Fire Firefighting Syste ms
G73. With reference to firefighting in machinery spaces compare the advantages and disadvantages of:
a) high expansion foam
b) high pressure water spray
G74. In respect to
firefighting why is
a) dry chemical powder preferable to sand
b) mechanical foam preferable to chemical foam
c) Halon 1301 preferable to CO2
d) light water foam (A.F.F.F.) preferabel to high expansion foam
G75. What preventative measures should be taken against the out-break of fire in an oil burning vessel? How would you proceed to subdue such an oil fire? Describe with the aid of a sketch, a foam type portable fire extinguisher.
G76. Make a detailed list of
all fire-fighting equipment on the last ship in which you sailed. Sketch the layout of engine room and boiler room, placing the
equipment in their respective positions.
G77. What is meant by the
term "permeability" in relation to fire prevention?
G78. State why a CO2 fixed
fire smothering system requires periodical inspection and service. Define the advantages and disadvantages of this system over other
G79. What is done to prevent
a) air starting lines
b) air compressors
c) engine crankcases
G80. Explain the advantages
and disadvantages of an inert gas smothering system from flue gasses
compared to an inert-gas generator. Explain
why an inert gas generator is more advantageous. Why is it unsuitable for
use in machinery spaces?
G81. With reference to
safety of personnel describe the correct method of dealing with the
a) entering a cargo pumping room when pumping crude petroleum
b) overhauling a pump that has been used for pumping hazardous chemicals.
c) entering a hold that has carried citrus fruit.
G82. Sketch and describe an
inert gas system using exhaust gas from main uptake:
a) scrubber and its process
b) safety devices
G83. Sketch and describe an
inert gas system from boiler uptakes. Explain why this system cannot be used for firefighting.
G84. Describe with sketches
a fixed fire smothering installation incorporating 'bulk storage' of
carbon dioxide. Make special reference to the following points:
a) calculation of the quantity of carbon dioxide to be stored
b) protection against leakage of the main stop valve
c) alarm system for warning personnel of release
d) maintenance of correct pressure and liquid level in storage tank
G85 More questions
like these can be found on Martin's Marine Engineering Page, click to
G85. Compare the relative merits of infra red, ultra violet and combustion gas (ionization) type fire detectors for use in machinery spaces. Explain why a combination of these types is more desirable than any one type individually.
G86. What are the probable
causes of fire breaking out in the engine room of a ship using oil fuel?
What precautions are taken to avoid this? Describe a system of detecting fire aboard ship and the method of
preventing fire breaking out? Discuss firefighting methods aboard ship.
G87. What equipment is
fitted on an oil burning vessel? How
is it used to fight a bilge fire in the engine room.
G88. A ship has been grounded and damaged severely under the engine room. After completion of repairs, what steps would you take to ensure that the machinery is in a condition ready to be operated.
G89. Describe an automatic
sprinkler and alarm system which is effective for protection against fire
in all parts of a passenger ship. The
system is to be of the "dry pipe" type. Explain the operation
and how it is reset.
G90. Sketch and describe an automatic sprinkler system as fitted on board ship and indicate in what locations sprinkler heads are fitted.
G91. Describe a combined
smoke detecting and CO2 fire extinguishing system.
G92. Describe a CO2 fire extinguishing system. How is it operated? What precautions whould be taken before using? What must be done to make it fully effective? What is permeability with regard to fire extinguishing equipment?
G93. Using a line diagram
describe a fire smothering system which draws inert gas from the funnel,
that is the exhaust of the main engine or boilers. Can such a system be used for extinguishing engine room fires.
What are the time-related problems inherent with inert gas systems
and how are they overcome.
G94. Describe the bulk CO2
fire extinguishing system and precaution for:
a) warning personnel
b) prevent valve leakage
c) alarm if control panel opened
G95. Describe a CO2 fire extinguishing system. In your estimation, what volume of gas would be obtained from a kilogram of liquid CO2 . What minimum amount would be required for a machinery space expressed on a % basis?
G96. What precautions are
taken on an oil burning ship and how would you deal with a fire? Sketch and describe a portable fire extinguisher.
G97. Discuss the factors
contributing to the initiation and propogation of fires in the cavenge
system of a diesel engine and the method of operation required to mitigate
such an occurrence.
G98. Re: fire detection
state the differences between cargo spaces and machine spaces. What types of devices are used and why.
How are these devices tested. Where are the devices located?
G99. A rating is killed in
the engine room. Write a
letter to your head office as to how this happened, and precautions
G100. The vessel of which you are Chief Engineer suffers a grounding. Write a report to the Superintendent of the company about the surveys and inspections subsequently carried out when the vessel was dry-docked in a foreign port.
G101. You are the chief
engineer of a vessel that has suffered a minor fire in the engine room
that burned off the wiring to essential pumps temporary repairs were made
to get vessel underway. Write
a letter to the company head office describing the incident and what
arangements have been made to effect a permanent repair at the next port
G102. You have been chief
engineer on a new ship for 1 year with fully automatic U.M.S. operation.
You were previously chief engineer on the sister ship with manual
operation. Write a letter to head office and discuss the advantages and
disadvantages. Highlight any
instances in which automatic was superior to manual operation.
G103. Although your vessel
is engaged upon a regular trade the specific fuel consumption has notable
increased whilst the average speed has correspondingly decreased in
comparison to previous voyages. As
chief engineer report to head office your investigations findings and
measures to correct this tendency.
G104. Your ship shows much
more fuel consumption than her sister ship. Write a letter to your manager explaining the reasons.
G105. It has been found
necessary to completely replenish all of the oil in the lubricating system
of a large motorship. (or
steam turbine ship). As chief
engineer write a detailed report to the Superintendent Engineer justifying
this heavy expenditure, the expendiencies required to prevent further
trouble during the voyage, and suggestions for permanent measures to avoid
recurrence of the initial problem.
G106. You had to discharge
to shore 200 tonnes of emulsified and contaminated fuel oil. You had attempted to regrevate and purify this oil bat were
unsuccessful. Write a report
to your head office explaining the above, how the oil became emulsified
and contaminated, and what steps have been taken to prevent a re-occurrance.
G107. As chief engineer prepare a list of the operating and maintenance procedures you would institute for the care of the main engine giving reasons for each procedure and the trouble likely to arise from neglect of such procedures.
G108. Arrange a fire party
with 6 ratings 3 engineers besides yourself for an engine room fire.
G109. Write a letter to the
ship owner or superintendent engineer describing an engine breakdown with
suggestion for avoiding a recurrence.
G110. What type of engine is
fitted in motor lifeboats? What planned maintenance measures are carried
out? Describe how you would
start a lifeboat engine.
G111. Describe the following
G112. Define the following
a) stress corrosion
b) corrosion fatigue
c) crevice corrosion
e) upper critical point
f) lower critical point
G113. Describe in detail
each of the following processes and give an example where each is likely
to occur in marine engineering:
a) corrosion fatigue
b) stress corrosion
c) creeping cracks
d) casting cracks.
State how in each case the initiation of the process is prevented or
G114. Write a short essay on
the corrosion of the ferrous metals. What methods may be adopted to prevent or retard corrosion?
G115. Describe a tensile test made on a specimen steel bar. Give a definition of each of the following:
b) yield point
c) ultimate stress
d) reduction in area
G116. Various tests are
carried out on material used for boiler construction. With reference to these tests, explain the following terms:
b) yield point
c) area reduction
d) ultimate stress
G117. What is meant by the
mechanical properties of the metals used in Marine Engineering? What is meant by:
b) ultimate stress
c) yield point
d) permanent set
G118. Define creep failure.
State the material used for the following:
a) superheater support and bolts
b) main support and bolts
c) turbine blade
G119. Briefly describe the tests made on a piece of metal to determine its suitability for use in engineering. Explain clearly what is meant by any four of the following metallurgical terms:
a) work hardening
b) case hardening
e) yield point
G120. Explain the process of annealing, tempering and case hardening. Give two examples of each on an engine.
G121. With reference to steel, what is meant by the following terms:
c) case hardening
Describe how these processes are carried out.
G122. Discuss tempering and
annealing. How would you
a) stern frame
b) old copper pipe
What is the difference between case-hardening and tempering
G123. State the chemical composition of the following metals and give their physical properties:
a) babbit's metal
b) stainless iron
c) stainless steel
d) monel metal
State a use for each of these metals in marine practice.
G124. Give the average composition of white metal. What is its melting point? What are the advantages of using it? What pressure will it stand and at what pressure will it give?
G125. State physical
properties of the following and give example where they may be used:
a) muntz metal
b) phosphor bronze
c) aluminium bronze
d) cupro nickel
G126. What are the
metallurgical compositions and mechanical properties for:
a) nodulous cast iron
b) high tensile steel
Why does a ship yard use these?
G127. State the approximate
proportion of carbon contained in cast iron and cast steel. Mention the
forms in which the carbon may occur therein. Compare the physical properties of these two metals and name some
of the more important parts of machinery for which cast steel is used.
G128. Name 3 methods of making steel and describe one fully.
G129. Define teh following
types of non-destructive methods of testing:
c) magnetic particle
d) dye penetrant
Give their advantages and disadvantages
G130. Describe the open
hearth process of manufacturing mild steel. What is the difference between acid and basic mild steel?
Compare mild steel with cast iron and state in an engine where each
is used. Why is open hearth steel preferred to bessimer steel?
G131. Enumerate the factors
that should be considered when choosing between a sand-casting process and
a die-casting process. Describe
with aid of a sketch the sand-casting process showing the pattern in the
flask and the names of the parts.
G132. Give the physical make
up and properties of metals for the following:
a) cylinder liner of a diesel engine
b) exhaust valve
e) boiler tube plate
G133. Compare the advantages
of forged and built-up crankshafts with special reference to the magnitude
of the stresses in the cranks. How
would you check the deflections by means of a dial gauge through one
revolution of the shaft? How are the readings obtained interpreted? How is weardown measured?
G134. You are appointed Chief Engineer of a 20 year old ship and are required to carry out an extensive survey of teh main propelling machinery. State what defects you would expect to find and what corrective measures you would take.
G135. Define the
responsibilities of a chief engineer:
a) immediatly prior to dry-docking
b) whilst the dock is dry
c) immediately prior to and after flooding
d) leaving the dock
Draft a list of standing orders to the engine department for
that period that the vessel is on the blocks.
G136. How would you know if
there were cracks in cylinder heads or liners. What would you do?
G137. A several year old steel ship has been laid up for some time and is going into drydock for inspection of the double bottom tank. state the precautions you would take. What would you expect to find?
G138. Any proposal to
operate a machinery space in the periodically unattended condition must be
taken into account the danger of fire, flooding and failure of supervisory
equipment. Describe how possibility of the latter two hazards may be
minimized, detected and brought to the attention of the designated watch
G139. Give a reasoned statement as to why pre-heating of a lubricating oil is very advantageous with respect to a centrifugal purifier. Explain why an extreme pressure oil and similar lubricants can only be purified in a clarifier.
G140. Give reasoned concerns
you would have when the clutch slips on a lube oil purifier other than the
problem of overheating.
G141. Compare the advantages and disadvantages of dynamic separation and static separation disregarding time. Why is a centrifugal separator not suitable for a bilge and ballast system? What governs and limits the discharge overboard?
G142. Describe a bilge system suitable for a ship with cellular double bottoms. By means of a simple sketch, show the positions of pumps, manifolds, suctions, etc.
G143. Describe in detail a
manifold and valves for a bilge suction system. Name the materials used and explain how a pipe is led through
a watertight bulkhead.
G144. Describe a bilge
pumping system for a cellular double-bottom ship. With the aid of a line diagram, show all suction manifolds and
G145. Describe an arrangement for filling and discharging ballast and double bottom tanks. What types of valves are used and why? Sketch a typical system. State the size of piping and pump capacity. Name the materials used.
G146. Discuss the advantages
of dynamic separation of oil over static separation other than time.
What part does the cylinder rotor with cone shaped discs play in
G147. With regards to lube oil purifier, explain why a large number of conical discs are fitted in the purifier.
G148. Discuss with reasons
the one statement that is not correct regarding oily water separators.
a) test cocks are situated to locate the oil-water interface
b) separational rate is inconsequential
c) overboard discharge is inconsequential
d) rise in temperature assist in the separation process
e) rate of separation is unrestricted
G149. Sketch and describe
the function and operation of an oily water separator. What are the penalties for polluting harbour waters?
G150. With reference to oily
a) outline the routine attention needed to maintain satisfactory
b) define the contribution of test cocks towards functional efficiency
c) give 2 reasons why oil might be carried over with the water
G151. Why are baffle plates,
coagulator positive displacement rotary pumps and not centrifugal pumps
used with oily water separators
G152. With reference to fire or explosion explain the significance of the following properties of a flammable gas:
a) vapor pressure
b) explosive limits
c) flash point
G153. Define viscosity and
flashpoint. State suitable
numbers for lube oil.
G154. What would be the effects of water contamination of fuel oil and lubricating oil? Describe a test for detecting the presence of water in oil. Discuss methods of separating water from oil.
G155. What impurities are
found in lubricating and fuel oils. What
effects do these impurities have on a diesel engine?
G156. With reference to
crankcase lubricating oil discuss the following:
b) dilution by fuel oil
c) water leakage
Describe tests that could be made to detect the foregoing contamination
G157. State why the
temperature of lubricating oil supplied to an engine needs close control.
Sketch and describe an arrangement and explain the principle of
operation of instrumentation and control equipment for automatically
maintaining the temperature of lubricating oil supplied to an engine at
its desired value.
G158. Describe a refinery
a) lubricating oil
b) diesel oil
c) fuel oil
G159. Describe the processes
c) boiler fuel
d) lubricating oils
are obtained from the crude product in an oil refinery
G160. Describe the
a) lube oil
b) fuel oil
c) heavy oil
What are the various tests made to a sample of fuel oil? Why are they
G161. What is air? What is combustion? Is it chemical or mechanical? What part does it play in combustion?
G162. Describe a submersible
pump for a passenger ship. State the materials used and its capacity.
G163. Describe a submersible
pump. What connections are
fitted to one and how is is controlled?
G164. Describe in detail an independent feed pump. Explain how the valve gear works and how it is adjusted.
G165. Sketch and describe a
steam operated duplex pump.
G166. Make a three point
comparison of the characteristics of centrifugal pumps with those of
positive displacement rotary pumps. Suggest
with reasons the type of pump most suited in each of the following
a) main lubricating oil circulation
b) domestic fresh water supply
c) steering gear or stabilizer actuation
G167. Sketch and describe a
rotary type variable oil delivery pump as used in an electro-hydraulic
steering gear. Describe the pumping action. What would happen if it ran for a long period of time without any
pumping action taking place?
G168. Sketch and describe a
pump other than of the reciprocating centrifugal or gear type. Suggest one shipboard application for which it might be best
G169. Explain why a simple
centrifugal type pump is unsuitable for bilge pumping duties. Sketch and describe how a centrifugal pump can be rendered suitable
for such duties.
G170. Give a simple
explanation of the nature and effect of cavitation in rotodynamic pumps.
Describe with sketches a supercavitating pump. State the purpose of such a pump and give an instance of current
G171. Explain why the
performance of a centrifugal sea water circulating pump 'falls off' in
service. State two ways in
which this 'fall off' is indicated. Describe
how the pump may be restored to its original performance.
G172. State how a keyless propeller is mounted and removed. Give 2 advantages of this type over a keyed propeller.
G173. How is a spare blade fitted to the hub of a built-up propeller? How is the blade adjusted?
G174. Sketch and describe a
pilgrim nut for securing a propeller to the screw shaft. Describe how this device is used to loosen the propeller on the
shaft when removal or inspection becomes necessary. Give four (4) reasons why this method is considered to be superior
to all other methods.
G175. Describe the procedure for removal of a propeller shaft. Describe an inspection of the propeller shaft. Give several reasons for the increased frequency between withdrawls of tailshafts for inspection purposes.
G176. Describe how you would
withdraw a propeller shaft and state what examination of the shaft and
stern tube you would make, describing any defects you might expect to
find. If the shaft was found
to be grooved near the after end, show
how you would determine the reduced horse power at which it would be safe
to run the engine.
G177. Sketch and describe a
method adopted to enable the tail end shaft of a twin-screw vessel to be
drawn out from the stern. State
size of shaft.
G178. Explain why it is advisable to examine propeller shafts at regular intervals of time. Describe an examination of a solid shaft that is carried in a wood lined, water cooled bearing.
G179. Why are shaft coupling
bolts a press fit in their holes and not a clearance fit. What would you look for during an inspection of these bolts.
G180. Sketch and describe a fluid coupling as used with a prime mover. Why are these couplings fitted?
G181. Sketch and describe a
system for indicating remotely the propeller shaft speed. Explain how, with the system selected, inaccuracies occur and are
kept to a minimum.
G182. Name three materials
that propellers are made from. What are the advantages and disadvantages
(if any) of each of these three materials. A vessel is in dry-dock; explain how
you would measure the propeller pitch.
G183. Make a single line
sketch and describe a simple control system for a C.P. propeller . Describe the "fail safe" device.
G184. You are in a foreign
port without docking facilities. Your propeller is damaged beyond repair.
Describe how you change propeller (vessel having main machinery
G185. With reference to main
refrigeration plant give a reason for each of the following operational
irregularities and state how it is dealt with:
a) rapid loss of crankcase lubricating oil in a "vee" block
b) gradual "fall off" in the refrigeration effect over a
comparative short period of time
c) icing up at compressor suction
G186. With reference to
freon refrigeration plants describe how:
a) "vee" block compressors are lubricated
b) overpressure on the discharge side is prevented
c) refrigeration circuit is cleaned when contaminated with oil.
G187. Describe a CO2 system of refrigeration stating the temperatures and
pressures in the various parts of the system and the materials used for
pipes, valves, and gauges. State
the advantages of this system over the Ammonia Refrigeration system.
G188. Why is ammonia a good refrigerant? Describe the operations of an ammonia system. What produces the low temperature in cold rooms? How is oil and air removed from the system? Give disadvantages of ammonia.
G189. Sketch and describe:
a) a refrigeration compressor crankshaft gland seal
b) a pressure switch for a refrigerator circuit
c) regulator for a refrigerator unit
G190. Describe with a sketch how piston rod glands are fitted on an ammonia or CO2 refrigerating
machine. What prevents the
refrigerant from leaking by?
G191. Sketch and describe a
refrigerating system with which you are familiar, giving all temperatures
G192. Sketch and describe a refrigerating system you are familiar with, giving pressures and temperatures. How would you charge such a system? How would you know when the system is fully charged?
G193. Describe an air
conditioning system for a passenger-car ferry. Explain in detail how the humidity of the air is measured and
G194. A pneumatic controlled
reducing valve controls the oil pressure to an engine. Tell where the valve is placed in the system, and how it operates
with the aid of a sketch.
G195. Describe with sketches
a centralized cooling system incorporating plate type heat exchangers.
Explain the purpose of this system and how it is achieved.
G196. Describe and emergency
electrical generation plant making particular reference to:
a) starting arrangements
b) lubrication and coolant systems
c) fuel supply
d) attention required
G197. Describe a pneumatic control and electric-mechanical control system. What are the requirements with respect to service. What are the main faults with each system?
G198. Describe with the aid
of a sketch the activating equipment for a ship's stabilizer. What advantage or disadvantage has the folding type of stabilizer
fin have over the axial withdrawable type.
G199. What are the valves
that operate on deck on a tanker.
G200. Explain how the
Prevention of Oil Pollution Act 1971 affects the normal operational
practices conducted within shipboard machinery spaces. Describe:
a) measures taken to comply with the Act
b) documentation involved
G201. Describe an
arrangement of cocks and valves to prevent a deep tank from being
inadvertantly filled with water when used for cargo or vice-versa. What are the disadvantages of having these tanks only partially
filled when in ballast?
G202. A ship is engaged in
filling the double bottom and deep tanks with fuel explain and describe:
a) dangers implicit in the operation
b) precautions that must be observed
c) legal requirements that must be adhered to.
G203. What gases are present
in oil tanks after pumping out? How would you remove these gases and what
are the dangers of these gases?
G204. What gases are found
in an oil tank after pumping out? How would you rid the tank of these
gases and make it safe to enter? What
precautions are taken near oil tanks and what could result from the
presence of gases in empty tanks?
G205. Why and where are
vents fitted to oil tanks? Why
is it necessary to fit a gauze to the end of these vents. State the gauze material and indicate how they are secured.
G206. The Great Lakes Sewage
Pollution Prevention Regulations expressly forbids the contamination of
these waters by raw sewage from ships. Using sketches describe 2 entirely different methods available for
dealing with raw sewage so as to comply with the intent of this
G207. On a diesel engine
crankshaft, explain what torsional vibration and critical speed means.
What are the dangers of running at a critical speed. How can these be reduced or eliminated.
G208. Discuss what would be
the best way repairs would be made by way of building up by weld, cropping
or installing new plate for the following:
a) puncture in a hollow rudder
b) part of the bilge keel torn away from the hull
c) a puncture of a large area of plate bulkhead near the bow under the
G209. State if you would
repair by cropping, building up or renewing on the following:
a) deck stringer with localized pitting
b) plating below scupper above waterline
c) plating at waterline
G210 More questions
like these can be found on Martin's Marine Engineering Page, click to
G210. Describe the
electric-welding process. State
how the materials are prepared for this process. Describe the tests that are carried out to the weld of a material
of an important nature.
G211. Explain welding
techniques. Where is this
technique used on hull, boiler and machinery repairs. What precautions would be taken.
G212. Describe a method of
electric welding suitable for use on board ship. Name the parts which can be welded.
G213. Sketch and describe a
waste heat boiler with oil burning capicities. What mountings are required.
are the advantages of this type of boiler. Sketch an outline of boiler showing path of exhaust gas.
G214. Sketch and describe a
high lift safety valve. State
the materials it is made of. What
is the advantage of this type of valve.
G215. Explain the causes and
effects and how they could be remedied for the following conditions in a
small auxiliary boiler:
a) insufficient air
b) excess air
c) water in the fuel
d) too low a fuel temperature
G216. Describe with the aid
of a sketch the operation of a CO2 recorder. Explain with reference to combustion, how to interpret the reading.
What is the cause of:
a) black smoke
b) yellow smoke from a boiler plant.
G217. Sketch and describe a
flash type distillation plant. Describe the precautions taken to ensure
the water is fit for drinking purposes.
G218. Explain why the fuel
supply to the burners of a periodically unattended auxiliary boiler
automatically cut-off in the alarm condition for low and a high water
level, high steam pressure, air failure and flame failure. Describe how and when you could safely test these devices.
G219. Describe a reverse
system for a set of H.F.O. engines
(slow speed). Sketch cams.
G220. Explain the reversing
a) steam reciprocating engines
b) steam turbines
c) gas turbines
d) direct diesels
e) reduction-geared diesels
h) controllable-pitch propellers
G221. If marks resembling flaws were noticed in a shaft of a crank pin,
what tests wyould you prefer to see if it is suitable for use? What would cause the flaws?
G222. Compare steam triple expansion to diesel engine.
State thermal effeciency of each
G223. Draw cards - 4 stroke
diesel why? and light spring.
State temperatures and pressures.
G224. Lubricating - through
a water space. Position in
relation to rings when injection occurs. How is the gas pressure prevented from entering oil lines.
G225. Sketch and describe a
diesel-electric propulsion system. Mention
advantages and disadvantages.
G226. Draw an indicator
diagram and describe it. Why
are drawcards taken and sketch one
G227. Sketch and describe a
rotary air pump.
G228. Sketch and describe a
lub oil system for a large diesel engine.
G229. Describe a 2 and 4
stroke diesel process and from what engine is the valve timing?
G230. Should you find a flaw
on a diesel engine crankshaft when inspecting it, explain the tests done
to determine the seriousness of the flaw. Give reasons how flaws can occur.
G231. Sketch and describe a
4 stroke indicator card and diagram. Mention the pressures and temperatures.
G232. Firing order in 6
cylinder 2 stroke and 4 stroke.
G233. Why are fuel pump near
injectors. If lines are
unequal how do you balance?
G234. Sketch and describe a flywheel that would be fitted to a large marine diesel engine. Show in the sketches how it is fitted and secured. What is the purpose of the flywheel? Recently some engine makers have considerably reduced the size of the flywheel. Explain how this can be done.
G235. Describe a system of
super or pressure-charging used by a four=stroke marine diesel engine
exhaust gas turbo. What is meant by 'overlap' as applied to this type of
Why is 'overlap' necessary?
G236. Some piston rings are
made with an eccentric shape, where the radial thickness is greatest
diametrically opposite the gap. Describe
the manufacturing process of these 'eccentric' piston rings. What advantage do these rings have over other types of piston
G237. How are the cylinder
lubricators fitted in a large marine diesel engine that has a water
jacket. How is thermal
expansion allowed for. Where
is the location of the lubricator outlet in relation to the piston rings
on the piston. Why is this
G238. Sketch and describe a fuel pump of the Bosch (jerk) type. What are the various components made of and how does the helical plunger control the amount of fuel injected? How is this fuel pump driven?
G239. Describe an air
starting system for a large diesel engine that is pneumatically operated.
Why is there overlap on the cams? How much overlap is required?
G240. Describe the
principles and operation of a 2- stroke and a 4-stroke marine diesel
engine. Illustrate the
operation of both engines with timing diagrams giving the expected angles.
State the make of the engines in both cases.
G241. Discuss advantages and
disadvantages of using the following as cooling media:
a) fresh water
State the effects should these reach a high temperature.
G242. What limits the power
in a cylinder of a given size. State the results if an attempt to raise
the power by injecting more fuel into the cylinder is made.
G243. On a 2- stroke diesel engine, why is a scavenge pump used? Describe an air scavenge system using a reciprocating air pump. How is it driven. How much greater is the capacity of the pump as required by the engine and why?
G244. Sketch the lower
piston crosshead arrangement as adopted in the Doxford opposed piston
engine. How is the piston rod
attached to the crosshead. and explain why this method is used.
G245. Make diagrammatic
sketch of a Scotch marine boiler 3.65m diameter and 3.0m long suitable for
pressure of 1400 kPa. Put in
all major sizes, such as shell and end plate thickness, stay size, etc.
and indicate various types of riveted joints used.
G246. Make a sketch of an
oil-burning system suitable for use with a marine boiler.
G247. Give a reasoned
statement as to why pre-heating of a lube oil is advantagous with respect
to a centrifugal purifier. Explain
why an extreme pressure or other similar oils are only cleaned in a
clarifier. Give reasons and
concerns you would have when the clutch slips on an oil purifier other
than creating heat.
G248. With regard to
instrumentation and control what is meant by the terms:
a) set point
b) fail safe
c) fail set
d) split range
G249. What causes
water-hammer in a steam pipe? How
can it be prevented?