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Q3. Describe the developments that have taken place in the design of bearings of slow speed marine diesel engines, including geometry and material, focusing on the reasons for such changes.

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Q9. Describe the developments that have taken place in the design of bearings of slow speed marine diesel engines, focusing on the reasons for such changes. (16) - 2024/FEB/09

Q4. Periodical Lubricating Oil Analysis, its correct interpretation and corrective measures are of critical significance for the maintenance of marine machineries. With reference to the modern analysis techniques employed for the condition of L.O, discuss the following:

A) Elemental (Spectrometric) Analysis

B) Fourier Transform Infrared (FTIR) Spectroscopy

C) Particle Count

D) Base Number Vs Acid Number

Q2. With reference to the burning of heavy residual fuel in the main engine:

a) State with reasons FOUR modifications which need to be made as compared with the same engine burning distillate fuels. (8)

b) State with reasons SIX properties you would require seeing in the specification for residual fuel indicating the effect EACH of these properties might have with respect to the storage and burning of the fuel. (8)

Q4. What are the key parameters analysed during lab testing of lubricating oil used in ship machinery, and how do these test results help in determining the condition of the oil and the health of the machinery? (16)

Q3. What are the key parameters used to assess marine fuel quality, and how do these parameters impact engine performance, fuel efficiency, and emissions control on a ship? (16)

Q9. a) Define the following conditions relating to lubricating oil

(i) Oxidation

(ii) Emulsification

(iii) Acidity (6)

b) Explain how each of the conditions in Q9 (a) is controlled by maintenance (5)

c) Suggest possible consequences if the conditions in Q9 (a) change and no corrective action is taken (5)

Q1. Describe following types of lubrication system with suitable examples

(a) Hydrodynamic Lubrication

(b) Hydrostatic lubrication

(c) Elasto-hydrodynamic lubrication

(d) Boundary lubrication

Q2.A. Explain how analysis of used lubricating oil can be used as a “health-monitoring” tool for diesel engines.

B. Describe how vibration measurement can be used with a main engine turbo-charger:

i. For fault analysis;

ii. For condition monitoring with respect to maintenance;

iii. As a substitute to opening up machinery for survey.

Q1. With regard to care of lubricating oils onboard, answer the following:

(a)  Microbial degradation of lubricating oil and measures to prevent the same

(b)  Methods of ensuring correct sampling is done for the purpose of shore based testing.

(c)  If the shore based testing results show an abnormal values of water content and TBN for the crank case lub oil of a slow speed main engine, what will be interpretation and subsequent action?

Q4. With respect to piston cooling in large two stroke marine engines;

A. Briefly discuss the relative advantages and disadvantages of oil and water for piston cooling.

B. Sketch a piston for a large two-stroke crosshead engines indicating the coolant flow.

C. State the causes of piston cracking and burning and how it can be avoided.

Q6. Give a list of the properties or test by which distillate and blended fuels may be specified or decisions be made on their fitness for use. Name the properties or constituents that may be found in a blended fuel having a high viscosity and high carbon content. Explain how they may cause problems in engine operation. (16)

Q9.  A report on the analysis of the main crosshead engine crankcase lubricating oil indicates the following contaminants or property changes. In EACH of the following cases give reasons for the possible causes of the contamination or property change, explaining how the actual cause would be detected; .

A. The presence of fresh water; B. White metal fragments; C. Reduced alkalinity reserve; D. Reduced anti oxidation reserve.