DieselShip's Online Content Library

Q6: With reference to electro-hydraulic steering gears:

A. Sketch and describe a steering gear with two 50% torque units conforming to the single failure criteria. (8)

B. State, with reasons, the precautions necessary when operating on two rams only; (4)

C. Describe the tests necessary to ascertain that the gear will operate as required when one side of the circuit develops a malfunction. (4)

Q10. A. Write shorts notes on various types of DC Motors.

B. A 440V shunt motor takes an armature current of 30A at 700 rev/min. The armature resistance is 0.7ohm. If the flux is suddenly reduced by 20 per cent, to what value will the armature current rise momentarily? Assuming unchanged resisting torque to motion, what will be the new steady values of speed and armature current? Sketch graphs showing armature current and speed as functions of time during the transition from initial to final, steady-state conditions.

Q3. A. With reference to the underwater surface of a ship’s hull; i. Describe a hull plate roughness analyser system;

ii. State the significance of the roughness profile and compare the typical roughness values for a new ship and a ship eight years old;

B. Which reference to the application of self-polishing paint in dry dock - i. Describe the plate preparation necessary;

ii. State the defects that may occur in the paint coating if it is not correctly applied.

Q1. With reference to International Load Line Statutory Certification,

A. State the reasons for the freeboard requirements;

B. (i) Explain the term “conditions of assignments”;

(ii) List the items that may be examined during a Load line survey after a vessel’s major repairs in the dry-dock.

Q7. Define briefly the construction details peculiar to each of the following types of closure that enables their primary function to be fully realized:

A. Water tight doors;             B. Fire proof doors; C. Gas tight doors,

D. With reference to above doors, State why (A) can perform function of (B) as well as of (C), whereas function of (B) and (C) are restricted solely to their primary function.

Q6. With respect to the hazardous areas of tankers,

A. Explain the term flameproof (Ex d) for electrical equipment;

B. State the type of electrical equipment that would be protected in this way.

C. List likely defects of flameproof equipment.

Q9. A. With reference to the insulation testing of marine electrical plant: - I. State the reasons for insulation testing; II. State the precautions to be observed when testing intrinsically safe equipment. B. Describe the overhaul of d.c. motor which has been subjected to excessively damp condition or flooding with seawater.

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

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?

Q9. A. Explain the potential hazards if liquid-cooled transformers are used.

B. What are the losses in transformers? Mention the various factors which affect these losses. In a 25 KVA, 3300/233 V, single phase transformer, the iron and full-load Cu. Losses are respectively 350 and 400 watts. Calculate the efficiency at half-full load, 0.8 power factor

Q2. A. Describe the procedure to be adopted for the inspection of a safety valve fitted to an exhaust gas fired auxiliary boiler stating, with reasons, which parts should receive particularly close attention.

B. Describe the procedure for the setting of safety valves of exhaust gas operated auxiliary boilers;

C. Explain the required action a watch-keeping engineer should take after the setting of safety valves as in (B)