DieselShip's Online Content Library

Q7. With reference to the lubrication of refrigeration compressors:

(a) state the advantage of using fully synthetic oils; (2)

(b) explain why oil may be carried over from the compressor; (3)

(c) describe a device which returns oil from the compressor discharge to the compressor sump; (3)

(d) state TWO reasons why an accumulation of oil in the evaporator is undesirable. (2)

Q2. With reference to pneumatically operated control valves:

(a) state the reason for fitting valve positioners; (4)

(b) with the aid of a sketch, explain valve hysteresis and how it affects the process; (3)

(c) describe how the design and routine maintenance can limit hysteresis. (3)

Q8. With reference to fresh water HI-FOG fire fighting systems:

(a) sketch such a system; (6)          (b) state how the system in (a) is activated; (2)

(c) state, with a reason, a suitable location for the above system. (2)

Q3. (a) Explain how power is transmitted through main propulsion shafting. (3)

(b) State THREE operational factors that may induce high stress in shaft coupling bolts. (3)

(c) Sketch a hydraulic type of shaft coupling bolt. (4)

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)

Q9. (a) Describe, with the aid of a sketch, a static excitation system for a generator.(8)

(b) Explain TWO advantages of static excitation.(2)

Q14. (a) With reference to the overhaul of a ship side valve in dry dock explain, as Chief Engineer Officer, what information should be given to the docking company prior to work commencing. (5)

(b) Describe how the valves would be overhauled stating the precautions to be taken before returning the ship to service. (5)

Q12. With reference to large fixed bladed propellers:

(a) describe, with the aid of a sketch, EACH of the following:

(i) the effect of hull fouling; (3)

(ii) operation in clean hull, ballast condition. (3)

(b) explain why fitting a light propeller may be beneficial. (4)

Q13. With reference to defects found in the steelwork of ballast tanks:

(a) explain the factors that may cause defects in ballast tanks; (4)

(b) state, with reasons, areas most likely to be affected and how they may be indicated; (4)

(c) state methods employed to minimise damage, caused by the factors in (a). (2)