DieselShip's Online Content Library

Q1. (a) Describe how leak in a Heat exchanger tube is detected? How to rectify leaky tube? (8)

(b) What are the common methods to enhance heat transfer of heat exchanger? (4)

(c) Describe reasons for poor performance of heat exchanger and actions to rectify the same. (4)

Q2. Describe the Stern Tube Lubrication System by drawing a schematic diagram and explaining function of each component. (16)

Q3. With respect to the properties of fuel oil, explain the significance of the following terms.

(a) Calculated Carbon Aromaticity Index (CCAI). (4)

(b) The importance of Sodium to Vanadium Ratio. (4)

(c) Sulphur content. (4)

(d) Pour point. (4)

Q4. (a) What causes cavitation in a Centrifugal pump operation? (6)
(b) If the Engine room Bilge pump not taking suction, explore the probable reasons? (6)
(c) Why is a centrifugal pump started with its discharge valve shut? (4)

Q5. (a) How will you align a motor-pump shaft? What are the different methods of alignment that can be used? (8)
(b) Why is the Fridge compressor belt Driven? (8)

Q6. (a) Explain why a purifier is not attaining its rated speed on starting from rest? (8)
(b) How do you select the appropriate Gravity Disc of Purifier? Why is this selection an important element in the purifier operation?

Q7. (a) What are the reasons for foaming in refrigeration compressor crankcase? (4)
(b) Describe the causes for the following in the domestic refrigeration system: (3*4)
(i) Frequent cut-in and cut-out of the compressor.
(ii) Lub oil low pressure cut-out of the compressor.
(iii) High pressure cut-out of the compressor.
(iv) Frosting in the compressor suction side.

Q8) (a) Describe the effects of taking fresh water from the shore as feedwater for auxiliary boilers. (5)

(b) Describe the measures taken to reduce these effects. (5)

(c) What is the purpose of deaerator in the boiler feed water system? How is the deaeration achieved? (6)

Q9. Describe the following turbocharger cleaning operations.

(a) Turbine side water washing. (6)

(b) Turbine side Dry Cleaning. (5)

(c) Blower side water washing (5)