DieselShip's Online Content Library

Q1. Explain the method of obtaining the following diagrams on a 2-Stroke Main propulsion Engine.

a) Power Card, showing vital point of diagram. (4)

b) Out of phase diagram indicating vital points. (4)

c) Light spring diagram, indicating vital points. (4)

d) Compression diagram and its importance. (4)

Q2. a) With reference to crankshafts and piston crowns outline the main stresses to which these parts are subjected. (4)

b) In each case explain how the stresses are generated and how they very in magnitude and direction during one cycle. (6)

c) With respect to the whole engine, describe how stresses may be accommodated by good design and influenced by poor maintenance. (6)

Q3. a) What is crankshaft misalignment? (4)

b) What are the reasons for crankshaft misalignment? (8)

c) What is the effect on main engine of such misalignment. (4)

Q4. Describe following terms with respect to Diesel Engine with suitable diagram:

(a) Natural aspiration (4)

(b) Scavenging (4)

(c) Supercharging (4)

(d) Types of Super charging in two stroke engine. (4)

Q5. a) Sketch and describe a fuel oil system of a large diesel engine, from settling tanks to main engine fuel injectors. (10)

b) Also, comment on the importance of

i) Heating arrangement with temperature control. (3)

ii) Prevention of air lock in the system. (3)

Q6. (a) How is a 2-stroke engine started? Describe the sequence of engine starting. (5)

(b) Draw the Timing Diagram of engine starting, showing crank position of each Step. (6)

(c) What is OVERLAP in engine starting? (5)

Q7. With reference to the construction of a turbocharger, sketch and describe

a) The rotor bearing and it's method of lubrication. (6)

b) Labyrinth seal and explain how such a seal work. (6)

c) Impeller and diffuser. (4)

Q8. a) Draw sectional diagram of exhaust valve of 2-stroke Diesel Engine. Name the different components of the valve. (8)

b) Describe working of the valve in operation. How valve rotation occurs during operation and its purpose. (6)

c) What is the special material used on valve lid. (2)

Q9.a) What are the difficulties observed in lubrication of gear teeth in gear trains? (4)

b) Describe with diagram, how good lubrication to gear teeth is achieved? (6)

c) What are the qualities of lubricating oil suitable for main Reduction Gearing of main engine? (6)