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Q6 . The steering gear operation of a vessel that recently experienced a heavy storm is found to be abnormally sluggish.

(a) State FIVE reasons for possible malfunction of the gear. (5)

(b) State the corrective actions that may be carried out at sea, that will allow the vessel to continue to the nearest port. (5)

Q3. With reference to main propulsion shaft systems:

(a) describe a method of hydraulic jacking to check bearing loads; (5)

(b) sketch the Bearing Load versus Shift Lift Dial Gauge Reading graph obtained by the method described in part (a), annotating the graph and how the characteristic of bearing load is obtained. (5)

Q4. (a) State the affinity laws for a centrifugal pump. (3)

(b) State the effects on the pump affinity laws of fitting a slightly smaller diameter impeller. (2)

(c)  Explain, with the aid of a Head versus Flow diagram, why a two speed pump is preferable to throttling where high and low capacities are demanded for a large sea water circulating pump.(5)

Q10. With reference to star delta starters used for three phase induction motors;

(a) explain in detail why this type of starter is employed. (4)

(b) explain, with the aid of a circuit diagram, the sequence of operation of a star delta starter. (6)

Q11. With reference to testing High Voltage equipment:

(a) explain why earthing down is considered essential; (2)

(b) state the operating voltage for an insulation resistance tester (megger) suitable for 6.6 KV equipment; (1)

(c) describe how an insulation resistance test is carried out on High Voltage equipment, making reference to personnel safety; (5)

(d) explain why infra red temperature measurement is used on High Voltage equipment. (2)

Q11. With reference to large electrical transformers on board ships:

(a) state where these transformers may be used; (1)

(b) state a typical efficiency range for a transformer; (1)

(c) state the regulations pertaining to transformers; (3)

(d) state the protective devices that are fitted; (2)

(e) describe the maintenance requirements. (3)

Q13. (a) With reference to bilge keels:

(i) describe how the design and method of attachment reduces the possibility of damage to the shell plate; (5)

(ii) state what testing must be carried out. (2)

(b) Explain why the bilge keels do not extend the full length of the vessel. (3)

Q14. As Chief Engineer officer, write a dry dock specification for the repair of the following damage that has occurred, stating what factors have to be considered when costing the repairs. Damage to water ballast tank number 1 port wing. The shell plating 15 mm thick for approx 2 metres square has to be removed and replaced along with the relevant damaged stiffeners. (10)

With reference to cargo hatch covers on large container ships:

(a) describe how they are tested for weathertightness; (2)

(b) explain how the weight of the hatch and containers is transferred to the ship's structure whilst allowing for deflections of the hull in a seaway;(3)

(c) describe, with the aid of a sketch, the type and location of damage that can occur due to wear of the hatch supporting arrangements. (5)