DieselShip's Online Content Library

Q1. (a) List the laboratory tests that may be carried out on specimens of steel for ship’s plate, stating reasons for these tests. (6)

(b) Outline FOUR features of a fracture in a component which would assist in the verification that brittle fracture has occurred. (4)

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)

Q3. with reference to oil filled stern tubes:

Describe, with the aid of a sketch, the principle of operation of a combination seal, which incorporates a wrapped bellows radial face seal and a lip seal.  (10)

Q4. with reference to biological sewage systems:

(a) describe the principle of operation of a biological sewage treatment plant; (4)

(b) state TWO operational factors that may adversely affect the operation of the plant and how the effects would be indicated;     (2)

(c) explain why, on a long sea passage, it is advisable to bypass the unit.      (2)

(d) explain the meaning and significance of the term biological oxygen demand.          (2)

Q5. with reference to centrifugal pumps;

(a) describe how EACH of the following improves pump performance:

??(i)raising the speed of rotation;??(2)

??(ii) multi-staging.??(2)

(b) explain the advantages of using centrifugal pumps instead of positive displacement pumps for lubricating oil circulating duties.??(6)

Q5. with reference to centrifugal pumps;

(a) describe how EACH of the following improves pump performance:

(i)raising the speed of rotation;      (2)

(ii) multi-staging.      (2)

(b) explain the advantages of using centrifugal pumps instead of positive displacement pumps for lubricating oil circulating duties.         (6)

Q7. With reference to the on-board production of fresh water for domestic purposes:

(a) explain the principles of operation of EACH of the following:

(i) low heat source evaporator; (2)

(ii) flash evaporator; (2)

(iii) reverse osmosis. (4)

(b) state the constraints placed on the installation and use of systems for shipboard production of fresh water.        (2)

Q8. As chief Engineer Officer, write a procedure listing recommendation for the safety precautions to be adopted when servicing accommodation lifts. (10)