DieselShip's Online Content Library

Q5. With respect to Air Starting systems for 2 stroke diesel engines:

A. Sketch a Main Engine starting air starting system and describe how it operates.

B. List the safety devices and interlocks incorporated in main engine air starting system and state the purpose of each.

Q6. State the various documents pertaining to a ship that a port state control inspector would ask for during port state control inspection. If your vessel-gets detained by the PSC owing to a deficiency, what would be your action for redressal

Q2. A. Describe the double bottom and framing arrangement used in the machinery space to cope up with the concentrated loads and vibration, together with shaft and thrust block support.

B. Give reasons for the choice of thrust block position.

Q8. For a fully automatic provisions refrigeration system incorporating a number of rooms; A. Explain how each room temperature is set;  B. Describe the sequence of events following a demand for increased refrigerant flow from one room;  C. State with reasons the devices incorporated into the system to protect the machinery and equipment against malfunction;  D. State how satisfactory operation of the plant can be established?

Q4. An auxiliary engine exhibits a tendency to hunt to such an extent that the engine speed variation prohibits the connection of the machine to the switchboard. A. Discuss the possible causes of hunting; B. Explain how the problem of hunting can be rectified.

Q9. A. List the factors that determine the starting torque of the three-phase induction motor. How does this torque generally compare with the value of the rated torque?

B. The low-voltage release of an a.c. motor-starter consists of a solenoid into which an iron plunger is drawn against a spring. The resistance of the solenoid is 35 ohm. When connected to a 220 V, 50 Hz, a.c. supply the current taken is at first 2A, and when the plunger is drawn into the “full-in” position the current falls to 0.7 A. Calculate the inductance of the solenoid for both positions of the plunger, and the maximum value of flux-linkages in weber-turns for the “full-in” position of the plunger.

Q6. A. Describe the normal criteria used for setting thermal protection relays and its advantage compared to magnetic types.

B. The low-voltage release of an a.c. motor-starter consists of a solenoid into which an iron plunger is drawn against a spring. The resistance of the solenoid is 35 ohm. When connected to a 220 V, 50 Hz, a.c. supply the current taken is at first 2A, and when the plunger is drawn into the “full-in” position the current falls to 0.7 A. Calculate the inductance of the solenoid for both positions of the plunger, and the maximum value of flux-linkages in weber-turns for the “full-in” position of the plunger.

Q6. With reference to the circuit breaker for an a.c. generator A. Describe the preventive maintenance carried out on the circuit breaker for an A.C Generator. B. Explain the sequence of events that might occur if the breaker opens on a short circuit and state the check you would require following such event. C. Give a safe procedure to follow should a main circuit breaker fail to open under fault condition.

Q4. Discuss the advantages and disadvantages of adopting the following policies for maintenance of main and auxiliary diesel engines. A. Planned maintenance; B. Condition monitoring; C. Periodic replacement of components. D. Break down maintenance

Q4. With reference to Auxiliary boiler safety valves;

A. Describe with the aid of Sketch the safety valve for an auxiliary boiler;

B. Identify with reasons. The parts that require particularly close attention during overhaul;

C. Describe how the safety valves are reset after an overhaul.

Q1. With reference to the provision of a shore electrical supply to a ship:

A. Sketch an arrangement for taking A.C. shore supply and checks to be carried out prior taking shore connection?

B. Describe the method of safely connecting the arrangement sketched in (A) to the shore Supply?

Q5. Discuss the consequences of failure to maintain correct clearances in the case of main diesel engine crankshaft and bottom end bearings. Sketch a bottom end bearing paying particular attention to the arrangement of ensuring uninterrupted flow of oil to the top end bearing.

Q4. A. Describe with the aid of sketches where necessary a vane type steering gear showing how to weight of the rudder and stock are carried and the arrangement that allow for wear down;

B. State how the vanes described in (A) are secured and the method of sealing the edges;

C. State how, if necessary, the steering gear is locked for rudder maintenance.

Q9. With reference to fatigue of engineering components:

A. Explain the influence of stress level at cyclical frequency on expected operating life.

B. Explain the influence of material defects on the safe operating life of engineering component.

C. State the factors which influence the possibility of fatigue cracking of an auxiliary boiler feed water pump shaft and explain how the risk of such cracking can be minimized.