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Q2: With reference to fixed installations for dealing with a machinery space fire - A. Describe with the aid of a sketch a typical installation; B. Explain the testing procedure for the equipment: C. Outline the testing procedure for; (i) Remote shut down;(ii) Other equipment to be used in the event of an engine room fire.

Q2. (a) Define the term Torsional Vibration with respect to an engine crankshaft, stating the effect that high levels can have on an engine crankshaft.

(b) Explain how engine deterioration influences the risk of Torsional Vibration, stating what can be done to minimise that risk.

(c) Explain possible reasons for the activation of a Torsional Vibration alarm after an engine has been started if there had been no previous history of such an alarm and if no maintenance had been undertaken on the engine whilst it was stopped.

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.

Q6. Sketch and describe a “fail safe steering gear” suitable for use on a tanker of more than 100,000 T dwt; Explain the sequence of events that take place when an oil leak takes place in one of the hydraulic pipe lines.

Q5. A. State why fixed pitch propellers have a poor efficiency when going astern.

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?

Q6. Hydrogen damage is a general term used for mechanical damage of metal caused by the

presence of hydrogen, briefly discuss the different types of hydrogen damage and how these damages can be prevented?

a) Hydrogen blistering (4)

b) Hydrogen embrittlement (4)

c) Decarburization (4)

d) Hydrogen attack (4)

Q7. Sketch an arrangement of propeller shaft and stern in which the tube is filled with oil and

a) Describe the attention it requires at sea

b) Suggest a method of repair when the rubbing surfaces Of the Oil seal get estate the defects that you would look for when the shaft is withdrawn in the dry-dock.

Q8. A. Sketch, and describe, a valve suitable for reducing air pressure and maintaining the reduced pressure within close limits. B. Describe the processes through which air from the starting air receivers should be treated before it is used in a pneumatic control system.

Q9. A) How is the power to weight ratio of an engine sought to be increased by continuous development? Discuss the limiting factors, what is the typical power to weight ratio of a slow speed marine diesel engine of current generation? (16)