DieselShip's Online Content Library

Q1. i) Define the term 'vibrations’ and through examples, explain 'periodic' and oscillatory motions. (4)

ii) Name the type of vibration and how they are classified. (4)

iii) Machineries on board operate with their own natural vibrations which generally indicate their health. Explain the term 'abnormal vibration ' and the sources from where they originate. (8)

Q2. What is mean by 'corrosion control'? List out the techniques used in effecting corrosion control and render brief explanation of same. Give one example each of their application. (16)

Q3. Make a comprehensive list of fuel oil, diesel oil & lubricating oil tanks on board; stating the purpose of each tank & their location. What was their approximate capacity on your last ship. (16)

Q4. i) what are the type of contaminants which affect lubricating oils? Briefly explain each of them. (6)

ii) what measures are adopted to prevent their entry into machinery lubricating oils systems. (4)

iii) How contaminated oils are dealt with on ships? Particularly in the case of bacterial attack. (6)

Q5. i) Why are deck cranes provided? Name the different parts of deck cranes and what is the advantage of carrying deck cranes? (6)

ii) Name the safety stops and 'cutouts' provided for safe operation. (4)

iii) What maintenance is required periodically? (3)

iv) What is rocking test and why same carried out? (3)

Q6. i) what are the types of pumps normally used for steering gear system? (3)

ii) Using a simple sketch explain the working principle of 'radial piston' type pumps. (8)

iii) What is understood by the term 'hunting action'? (5)

Q7. i) Sketch and describe a composite boiler and explain its working principle. (12)

ii) What do you understand by the term 'Heat Recovery'? Briefly explain as to how it contributes to increasing plant efficiency? (4)

Q8. i) Explain the basic theory of air compressors using a basic P-V cycle diagram, for a single stage air compressor, showing (a) adiabatic (b) polytropic (c) isothermal lines of compression. (6)

ii) Explain the advantages of multistage compression and intercooling. Superimpose the effects of both on the P-V diagram mentioned above. (6)

iii) Briefly explain bumping clearance. (4)

Q9. i) In a refrigeration and air-conditioning system, what are the different methods for detecting gas leakage? (3)

ii) Name different types of detectors available and state how they are used to identify point of leakage. What safeties are observed when performing 'leak detection'. (4)

iii) Explain how leakages in the piping system are rectified (a) temporarily (b) permanently? (5)

iv) What records are to be created and maintained whilst carrying out repair / maintenance on the refrigeration system? (4)