DieselShip's Online Content Library

Q4. (a) State the different types of turbo charger fitted in modern diesel engines (8)

(b) Describe the function of the (8)

(i) Nozzle ring

(ii) Labyrinth seals

(iii) Diffuser and

(iv) Inducer

Q4. With reference to a turbo-charging system of an engine:

a) State the parameters that you would check while taking over the watch. (8)

b) Action to be taken in the event of turbo-charger is observed to vibrate abnormally. (8)

Q4. (a) What are the causes of Turbocharger surging? How is it indicated to the watchkeeper? (8)

(b) What are the possible remedial action? (4)

(c) What are the reasons for excessive fouling of the turbocharger? (4)

Q1. Sketch and describe a turbocharger bearing lubrication system. State the type of bearing employed and explain the advantages and disadvantages of the lubricating system described.

Q1. (a) Explain the types of turbocharging in a marine diesel engine. (8)

(b) What are the reasons that may induce vibration on a main engine turbocharger? (8)

Q2. Describe with aid of sketches, a turbocharger bearing lubrication system, stating the type of bearing employed and explaining the advantages and disadvantages of the lubricating system described. One of the turbochargers of the main engine on the vessel aboard which you are serving as second engineer has suffered a sudden and unexpected failure. Write a letter to the ship owner/operator concerning the incident and stating the action taken in bringing the turbocharger back into service.

Q3. With reference to turbochargers:

(a) Explain the term surging, stating how it occurs, its effect on the turbocharger and how it can be avoided (8)

(b) Describe the procedures for cleaning EACH of the following and explain the precautions which should be taken: (8)

(i) Suction air

(ii) Turbine blades and nozzle ring

Q9. During normal engine operation, a turbocharger rapidly loses speed and the speed reduction is accompanied by appreciable noise -

A. State with reasons the possible causes.

B. Explain in detail how the engine might be safely operated if the damage caused by this incident is such that the turbocharger cannot function.

C. State with reasons the factors which may limit engine operating speed with the turbocharger out of operation.

Q5. (a) Why exhaust outlet of marine diesel engine turbocharger is lower than inlet temperature? (6)

(b) Why do we need an air cooler and why is the scavenge air temperature maintained at 40°C? (10)

Q4. Referring to latest developments in Turbo charger application in marine diesel engines, write short notes on the following:-

(a) Power turbines Generators.

(b) Hybrid Turbo Chargers.

(c) Electro-assist Turbo chargers.

Q9. With reference to Main Engine Turbo charger

(a) What are the indication of water leakage in turbo charger casing. (8)

(b) Precaution to be taken during water washing at sea (8)

Q4. Many modern turbochargers use sleeve type bearings for rotor support.

A. Explain the reasons for their preference over the rolling contact bearings;

B. With a sketch describe the lubricating system provided for this type;

C. In a turbocharger with integral type of bearings, describe the procedure for renewing the bearings.