DieselShip's Online Content Library

Q1. With Respect to a turbocharged 2-Stoke Main Propulsion Diesel Engine:

a. What is the purpose of Auxiliary Blower.

b. What are the safeties provided for the scavenge air receiver.

c. Why do we require scavenge air cooler?

Q2. With respect to a 2- stroke main propulsion diesel engine draw and explain the following

a) How the various sections of exhaust manifold connected together for the main engine?

b) What is the arrangement for thermal expansion of different sections of the manifold?

c) What is the arrangement in the exhaust manifold to prevent broken pieces of piston rings entering turbine of the T/C? (16)

Q3. Why is it necessary to cool the cylinder head covers and cylinder liners and pistons of slow and medium speed engines? What are the different cooling mediums used for cooling slow and medium speed Engines explain with reasons? (16)

Q5. With reference to LNG diesel engine installations:

(a) Describe, with the aid of a sketch, a Gas Valve Unit, explaining its purpose and indicating where it is located in the gas train. (6)

(b) Explain why ventilation and inert gas systems must be installed with the engine fuel gas system. (5)

(c) State why pilot injection must be provided when burning fuel gas, explaining how a pilot injection system works (5)

Q4. While operating at Sea during rough weather conditions, fire sparks have been observed coming out from the chimney. On investigation, it has been observed that the fuel contains considerable quantity of water and sludge. As the Second engineer of the vessel. Explain:
A. Immediate actions taken to rectify the problem.
B. Precautions you take to avoid recurrence of this type of problem.

Q5. With respect to Air Starting systems for 2 stroke diesel engines:

A. Sketch a Main Engine starting air starting system and describe how it operates.

B. List the safety devices and interlocks incorporated in main engine air starting system and state the purpose of each.

Q6. With Respect to main engine turbocharger;

A. Explain why cleanliness throughout the turbochargers system is critical to engine performance?

B. Describe in-service cleaning procedure for gas and air sides of a turbocharger indicating safety precautions to be observed?

Q5. State the probable engine defects and rectifying action needed if the following conditions are indicated on a single unit of a large two-stroke marine diesel engine giving seven units. State any additional information which might be of help in forming on option.

A. Increased exhaust temperatures.    B. Reduced exhaust temperature.

C. Reduction in jacket cooling water return temperature.

D. Increase in jacket cooling water return temperature.

Q9. a) To improve the power-to-weight ratio of an engine, it is necessary to increase the mep. Discuss the importance of turbocharger compression ratio in this regard. Why has it become necessary to introduce two-stage turbocharging? (8)

b) With reference to turbochargers with variable turbine area, explain (8)

i) Which area is varied

ii) Why is it varied

iii) How is it varied.