DieselShip's Online Content Library

Q6. (a) Describe the constructional features of plate type freshwater generator and its operational procedures for fresh water generation. (6)

(b) State the temperatures and pressures at salient points. (4)

(c) State some of the advantages and limitations that exist in using a plate type heat exchanger. (6)

Q7. State the causes and remedial actions to be taken in case of the following detected on a reciprocating air compressor:

(a) Water mixed in the crankcase oil (4)

(b) LP safety valve blowing (4)

(c) Bursting disc rupture (4)

(d) Defective piston rings (4)

Q3. (a) Sketch a line diagram showing a typical 'Inert Gas System' used for inerting the cargo tanks of oil tankers, labelling the component parts. (8)

(b) Describe the system. (8)

Q4. A distinguishing feature of an eductor, when compared to other pumps, is the (16)

(a) Discharge end being smaller than the suction end

(b) Small size of impeller

(c) Lack of moving parts

(d) Ease at which the wearing rings may be changed

Briefly justify your answer.

Q4. a) Whils't on ‘seawatch’ you observe that the Oil Mist detector (OMD) in the engine room has triggered an alarm, and in feeling the crankcase doors on the bottom platform, you find that the unit in question feels warmer than the rest. What pre-emptive action will you take as Watch-keeper to bring the situation under control. (10)

b) Draw a simple line diagram of an ‘OMD’ and explain it’s working. (6)

Q1. With reference to control system state, explain in brief:-

a) Two step action. (6)

b) Proportional control. (5)

c) Offset. (5)

Q3. (a) Why Engineering Materials are tested prior manufacturing of their components. (6)

(b) Describe the various destructive and non-destructive tests carried out on materials for shipboard used. Explain the purpose of each test and where the same applied. (10)

Q8. (a) Explain 'short cycling' in the context of refrigeration and air conditioning systems onboard ship. State its causes and how it can be avoided. (6)
(b) State the symptoms of 'overcharging' and 'undercharging' in refrigeration system. What are its effects and state remedial measures (5)
(c) What are the visible indicators of oil in refrigeration system. What would be its effects? State remedial measures (5)

Q9) Write short notes on:

(a) Control air dryer - working principle with diagram, of any one type of dryer of your choice (8)

(b) Any two types of Ballast water treatment system (8)

Q1.a) What are the different types of coupling bolts used in practice? Name at least 3. (3)

b) Explain with the help of sketch, as to how a ‘pilgrim’ hydraulic bolt is fitted and removed? (8)

c) How are fitted boards installed on the coupling? (5)

Q2. (a) Explain the working principle of a fuel oil purifier. (8)

(b) Explain briefly the significance of the friction clutch mechanism. (4)

(c) List the alarms and trips associated with a purifier. (4)

Q3. Which of the materials listed is used as the dynamic seal material on mechanical seals installed on most centrifugal pumps used in water service? (16)

(a) Copper.

(b) Copper and carbon.

(c) Carbon.

(d) Bronze.

Briefly justify your answer.

Q4. (a) Sketch and describe a central cooling freshwater system for a motor ship. (8)

(b) State the possible causes of corrosion in the closed system described in (a). (4)

(c) Explain how protections against corrosion is provided? (4)

Q5. (a) State why the presence of oil in boiler water is considered serious. (4)

(b) Suggest likely sources of oil contamination. (4)

(c) Describe how the source is traced. (4)

(d) Describe how the whole steam plant is restored to oil free conditions. (4)

Q6. Describe the following metallurgical tests and explain why EACH is carried out:

(a) Impact test (4)

(b) Hardness test (4)

(c) Endurance test (4)

(d) Tensile test (4)

Q7. If a radial piston hydraulic pump fails to deliver rated fluid volume, the cause can be (16) (a) Contaminated fluid

(b) Pitted thrust rings

(c) Worn pintle bearings

(d) Obstructed suctions passage

Briefly justify your answer.

Q8. Write short notes on the following:

(a) Incinerators (5)

(b) Airline relief valve (5)

(c) Mixing column (6)

Q9. (a) Make a detailed sketch of a direct expansion two room refrigeration system. (10)

(b) Give a full description of such a Refrigeration System, explaining the purpose of the relevant control and safety devices. (6)