DieselShip's Online Content Library

Q1. Explain the effects of the addition of EACH of the following alloying elements to improve the characteristics of steels:

(a) chromium; (2)                 (b) manganese; (2)               (c) molybdenum; (2)

(d) nickel; (2)                        (e) vanadium. (2)

Q2. (a) Describe, with the aid of a sketch, a temperature measuring instrument that uses the principle of operation of a change in resistance with the application of heat. (6)

(b) Describe how the instrument sketched in part (a) is tested and calibrated. (4)

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)

Q4. With reference to microbacterial infestation:

(a) list the engine room systems that may be affected by this type of contamination; (2)

(b) describe the conditions required for bacteria to evolve; (6)

( c) describe how the presence of microbial contamination could be detected. (2)

Q5. With reference to activated fin stabilisers, explain EACH of the following:

(a) why such units are preferred to passive tanks in large vessels; (3)

(b) why these units are preferred for passenger and fast cargo ships; (3)

(c) why partial, rather than maximum damping of ship movement in heavy weather, is advisable for reasons other than overstressing the fin stocks and activating gear. (4)

Q6. With reference to a vapour compression refrigeration plant:

(a) explain the purpose of EACH of the following:

(i) expansion valve; (2)                  (ii) room thermostat; (2)      (iii) high pressure cut out. (2)

(b) explain why EACH of the following conditions are desirable:

(i) superheating at the compressor suction; (2)

(ii) undercooling at the condenser outlet. (2)

Q7. With reference to deck machinery:

(a) sketch a line diagram showing the layout and components of a hydraulic system with a variable delivery, pressure compensated pump and accumulator, suitable for the operation of deck machinery(5)

(b) discuss the advantages of using electrically driven machinery over hydraulically driven winches and windlasses. (5)