DieselShip's Online Content Library

Q5. With reference to main air turbochargers:

a) Give a reason why binding wire is frequently fitted near the top of the blades

b) Mention one fault that occasionally develops with binding wire in services,

c) Define the cause and identification under running conditions of turbine blade damage

d) State how (c) can be largely avoided.

Q3. Describe, with the aid of sketches, a system of turbo-charging a two-stroke cycle main engine. State the routine attention, which should be given to the turbo-charger. Which parameters are to be recorded during watch keeping? (16)

Q9. a) Draw a simple sketch of turbocharger, describing each component. (8)

b) Describe how compressed air is delivered by the turbocharger to main engine? (4)

c) What arrangement is provided on turbocharged 2-stroke main diesel engine to provide compressed air while starting of main engine. (4)

Q8. 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)

Q7. Describe the following turbocharger cleaning operations.
(a) Turbine side water washing. (6)
(b) Turbine side Dry Cleaning. (5)
(c) Blower side water washing (5)

Q4. Describe the nature and the possible effects on machinery operation of deposits, which may adhere to the internal surfaces of exhaust gas turbo-blowers and explain how these deposits are removed. (16)

Q6. Following a recent turbocharger (T/C) overhaul, it has been observed that the scavenge air pressure is lower than before, and the engine power output has also been reduced.

a) State the possible causes of the problem with reasons. (5)

b) State the engine operational information that should be gathered to detect the possible causes of the problem, along with reasons for each type of information. (5)

c) State the instructions which should be issued with respect to future T/C overhauls in order to prevent similar incidents. (6)

Q6. with reference to a slow speed diesel engine fitted with a single turbocharger. describe, with reasons, the possible action which could be taken to enable the main engine to be operated, If whilst on oceanic passage, a small portion of one of the impeller vanes breaks off and impacted with the charge air cooler.

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

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.

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)

Q8. Explain why the use of residual fuels for the operation of large slow speed or of medium speed engines, may be responsible for the following problems with turbocharger nozzles, shrouds and blades and how in each, the problem may be minimized:

A. Build-up of deposits.

B. Hot corrosion.

C. Erosion (16)