Page 355 - Ship Construction.DJ Eyres 6Ed

Ch31-H8070.fm Page 344 Wednesday, October 18, 2006 7:06 AM
344 Ship Construction
to sub-division requirements can result in the ship being able to load to
deeper drafts. This is particularly the case with bulk carriers since these
vessels can often be designed to obtain the ‘B-60’ freeboards; and where
this is impossible some reduction in freeboard may still be possible. The
Convention allows freeboards between that assigned to a Type ‘B’ and a
Type ‘B-60’ where it can be established that a one-compartment standard
of sub-division can be obtained at the draft of a Type ‘B’ vessel, but not at
B --- ใช้เพื่อการศึกษาเท่านั้น---
the draft of a Type ‘B-60’.
Ore carriers of normal layout arranged with two longitudinal bulkheads
and having the side compartments as water ballast tanks, are particularly
suited to the assignment of Type ‘B-100’ freeboards, where the bulkhead
positions are carefully arranged. In the case of Type ‘A’, Type ‘B-100’, and
Type ‘B-60’ vessels over 225 m the machinery space is also to be treated as a
floodable compartment. The full sub-division requirements are given
below.
Damage is assumed as being for the full depth of the ship, with a penetra-
tion of 1/5 the beam clear of main transverse bulkheads. After flooding the
final water-line is to be below the lower edge of any opening through which
progressive flooding may take place. The maximum angle of heel is to be
15°, and the metacentric height in the flooded condition should be positive.
ึ

Type งานห้องสมุด ศูนย์ฝกพาณิชย์นาวี
Length
Sub-division requirements
A Less than 150 m None
A Greater than 150 m To withstand the flooding of any compartment
Less than 225 m within the cargo tank length which is designed to
be empty when the ship is loaded to the summer
water-line at an assumed permeability of 0.95
A Greater than 225 m As above, but the machinery space also to be
treated as a floodable compartment with an
assumed permeability of 0.85
B+ — None
— None
B–60 100 to 225 m To withstand the flooding of any single damaged
compartment within the cargo hold length at an
assumed permeability of 0.95
B–60 Greater than 225 m As above, but the machinery space also to be
treated as a floodable compartment at an
assumed permeability of 0.85
B–100 100 to 225 m To withstand the flooding of any two adjacent
fore and aft compartments within the cargo
hold length at an assumed permeability of 0.95
B–100 Greater than 225 m As above, but the machinery space, taken alone,
also to be treated as a floodable compartment at
an assumed permeability of 0.85