Answer Construction Question 23

Question 23: (a) Draw the mid ships section of an oil tanker with Double Hull & name each part.

(b) What is Bow Flare? Why is it so important in Bulk Carriers?

Answer: (a) Mid ships section of an oil tanker with Double Hull

(b) Bow flare:-

Flare is the outward curvature of the shell above the water line at the forward end of the ship.
It increases buoyancy thus limiting shrinkage of the bow into head seas, promoting dryness forward and provides a wider forecastle deck allowing the anchors to drop clear of the shell plating.
It deflects green seas, increase the local reserve of buoyancy, reduce the pitching amplitude and increase the height of the righting arm curve.

For a bulk carrier:-
Load line regulations regarding hatch covers requires that hatch covers be able to withstand load of 1.74 tons/m-sq; due to sea water and a minimum scantling of 6 mm for the tops of the hatch covers.
This standard requires that the pressure due to sea water be calculated as a function of free-board and speed, especially for hatch covers located on the forward portion of the ship.
This makes bow flare critical for the bulk carriers in respect to prevent heavy sea water load to impact on hatch covers.

Bow flare. Importance on bulk carrier