Question

(a) Describe how water tightness is maintained where bulkheads are pierced by longitudinal beams or pipes. (6)

(b) A ship of 15000 tonne displacement has an Admiralty Coefficient, based on shaft power, of 420. The mechanical efficiency of the machinery is 83%, shaft losses 6%, propeller efficiency 65% and QPC 0.71. At a particular speed the thrust power is 2550kW. Calculate: (10)

(i) Indicated power

(ii) Effective power

(iii) Ship speed

Answer 1

Part (a)

Water tightness of

bulkheads that are pierced by longitudinal beams or pipes:

Bulkheads must be made structurally watertight without the use of wood packing.
Pipes passing through bulkheads are either welded or fastened to the bulkhead using studs or hoses secured through tapped holes in the plating.
When a bulkhead is pierced by a longitudinal beam, the openings are kept as small as possible, and doubler plates are welded on each side to maintain watertight integrity.
Sealing materials and gaskets are used, particularly for pipes, cables, and similar penetrations.

✓ Verified Model Answer (Text Solution)

Water tightness of