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)

Q1. Describe the examination you will carry out on the following parts of Air Compressor,

a) Suction and delivery valves and seats. (4)

b) Relief valves and bursting discs. (4)

c) coolers and cooling passages. (4)

d) Piston and piston rings. (4)

Q2. The exhaust temperatures of an auxiliary diesel engine are found to be excessive and uneven at normal load, with dark exhaust at the funnel.

Describe EACH of the following:

a) An investigation of the situation. (5)

b) The procedure to remedy the immediate problems. (6)

c) Any further action that might be necessary. (5)

Q3. A Centrifugal pump has been opened up due to abnormal noise:

a) List the checks you will carry out on various parts (4)

b) Name the parts which may require replacement. (4)

c) Checks to be carried out after assembly. (4)

d) Operational parameters, which may be required to be compared with manufacturers test records. (4)

Q4. With reference to auxiliary boilers

(a) Briefly describe the maintenance procedures for oil burning equipment. (5)

(b) Explain the need for and the use of soot blowers. (5)

(c) Describe how a boiler should be taken out of service. (6)

Q5. An air cooler of a large two stroke marine diesel engine is showing poor performance. Suggest some measures you would initiate to rectify the problem and improve the performance. (16)

Q6. Briefly explain the following:

(a) How would you know if a refrigeration system is 'undercharged'? (4)

(b) What should you do to ensure that there is no water leakage into the engine cylinder before preparing main engine for sea? (4)

(c) What would be the probable cause of a rise in the level of the lub oil sump tank of a main engine? (4)

(d) How does the valve rotator as fitted on an exhaust valve of aux. engine work? (4)

Q7. With reference to Steering Gear & Hydraulic Power Rotary pumps:

(a) Explain how the reserve of fluid in the system is checked and how make-up is achieved? (5)

(b) Describe how a steering system is tested prior to leaving port with reference to SOLAS (5)

(c) Explain how tests are made for leaks, and air and other gases are bled from the system. (6)

Q8. With respect to centrifuges.

(a) Explain the reasons which shall cause a purifier to overflow (6)

(b) What are reasons that induces vibration in a purifier" (4)

(c) Explain the process of desludging? Why is the purifier amperage an important parameter for the operator? (6)

Q9. With reference to stuffing box of a two-stroke main engine explain following

a) Why stuffing box is required in two stroke diesel engines. (8)

b) Explain the maintenance carried out on stuffing box during piston overhaul. (8)