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Q2. Sketch a high-lift safety-valve lid and seat detailing their special features. Describe how such a valve is overhauled and any clearance that should be measured and noted. (16)

Q5. A. Sketch a four-ram steering gear arrangement capable of 100% redundancy; B. Describe the operation of the arrangement sketched in A.

Q3. Sketch and describe a cargo space inert gas system producing washed gas from either a main boiler or from an independent gas generator module. Elaborate the alarms and cut-outs incorporated in the system to prevent any accident.; Explain the various protections for cargo tanks with respect to pressure vacuum build up inside the tanks.

Q9. With reference to fatigue of engineering components:

A. Explain the influence of stress level at cyclical frequency on expected operating life.

B. Explain the influence of material defects on the safe operating life of engineering component.

C. State the factors which influence the possibility of fatigue cracking of an auxiliary boiler feed water pump shaft and explain how the risk of such cracking can be minimized.

Q5. 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.  Describe: - 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: - A double volute casing; (ii) A diffuser ring

Q6. With reference to Liquefied Natural Gas Carriers (LNG), explain the inspection you will carry out on the following equipment’s - A. LNG Vaporizer; B. Re-gasification plant; C. Cargo pumps; D. Emergency discharge pumps.

Q5. A. Explain why it is essential to ensure adequate cooling of air compressor cylinders, inter coolers and after coolers; B. State with reasons the possible consequences of prolonged operation of the compressor if these areas are not adequately cooled.

Q4. With respect to container ship: (16)

i. Sketch and describe a ship’s indirect refrigeration system arranged for cooling containers showed in stacks in the hold.

ii. State the advantages of the system described in (i) compared with containers with their own refrigeration self-contained units.

Q9: With reference to sleeved keyless propeller assemblies: 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: (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. C.  State the correct procedure for the removal of the propeller from tail end shaft