Page 37 - Ship Construction.DJ Eyres 6Ed

Ch03-H8070.fm Page 26 Wednesday, October 18, 2006 6:52 AM
26 Ship Construction
Length 77.6 m Deadweight 1680 tonnes Length B.P. 330 m
Beam 10.4 m Beam 53.3 m Deadweight 332 000 tonnes
Depth 5.8 m Speed 10 k Depth 32 m Speed 14½ k
Expansion trunk

Wing tank Centre tank Wing tank
Wing Wing
Centre tank
tank tank
SBTเท่านั้น---

งานห้องสมุด ศูนย์ฝกพาณิชย์นาวี
Double bottom
(a) (b)
DOUBLE-HULL TANKER MID-DECK TANKER PRINCIPLE

--- ใช้เพื่อการศึกษา
Wing Wing Oil Oil SBT
SBT Centre SBT
tank Mid-deck
tank tank Oil
Oil
SBT
SBT SBT SBT ึ
SBT
FIGURE 3.6 Oil tankers

growth increased enormously to meet the expanding demand for oil until
1973/1974 when the OPEC price increases slowed that expansion and led to
a slump in the tanker market. It is unlikely that such a significant rise in
tanker size and rise in speed will be experienced in the foreseeable future.
Structurally one of the greatest developments has been in the use of
welding, oil tankers being amongst the first vessels to utilize the application
of welding. Little difficulty is experienced in making and maintaining oil-
tight joints: the same cannot be said of riveting. Welding has also allowed
cheaper fabrication methods to be adopted. Longitudinal framing was
adopted at an early date for the larger ships and revision of the construction
rules in the late 1960’s allowed the length of tank spaces to be increased,
with a subsequent reduction in steel weight, and making it easier to pump
discharge cargoes.
As far as the general arrangement is concerned there appears always
to have been a trend towards placing the machinery aft. Moving all the
accommodation and bridge aft was a later feature and is desirable from the
fire protection point of view. Location of the accommodation in one area
is more economic from a building point of view, since all services are only to
be provided at a single location.