Construction of Transportation Means - Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation - page 48

Table 3.10 Main types of ships

Ship type Technical description

Bulk carriers Bulk carriers are cargo ships used to transport bulk cargo items such as ore

or food staples, e.g., rice, grain, and similar cargo [ 56 ]. There are double
or folding bulk heads. For balance, bulk carriers have lower and upper
wing tanks. The bridge is installed near the stern. The ships usually have
five to nine holds, often of different lengths. The transverse bulkheads
are either designed as double bulkheads or as folding bulk heads

Container ships Container ships carry standardized 20 or 40 TEU containers [ 57 ]. There are

also different lengths. Today all container ships are propelled by diesel
engines and reach speeds of 24-27 kn, depending on their size and
service. Feeder ships sail with 19 kn or less. Container ships have a lot of
open spaces on the main deck which reduces the torsion rigidity of the
ship's hull

Ro-Ro ships Roll-on and roll-off ships or ''Ro-Ro'' ships are cargo ships designed to

carry wheeled cargo such as automobiles, trailers or railway carriages
[ 58 ]. The vehicles enter and leave the ship after arrival at the port of
destination

Refrigerated ships Special refrigerated ships are used for the transport of perishable foods such

as meat, fish, or fruits and vegetables [ 59 ]. These ships are developed
from the usual dry cargo freighters but they have a higher speed and
appropriate cooling equipment including extensive insulation

Tankers for liquid
cargo

Liquid cargo is generally carried in bulk aboard tankers, such as oil,
chemical and LNG tankers [ 60 ]. Tankers have a closed main deck, apart
from the relatively small tank hatches, which influence the stability of
the ship to a limited extent. If the ships run aground or are involved in
collisions, large quantities of oil could spill. Therefore, the ship has to be
equipped with a double bottom and a double outer skin. Recent
legislation still provides for the phasing out of a single bottom
construction tankers.
DWT of large oil carriers is usually above 300,000 t (661 9 10 6 lb) and
the engine's performance is 25,000-28,000 kW (33,557-37,584 HP).
The ships achieve a speed of 15-16 kn
LNG carriers are on average smaller than oil tankers and reach a DWT
of 10,000-12,000 t (22.1-26.5 9 10 6 lb) [ 61 ]. The capacity is 50,000-
70,000 m 3 ((1.79-2.50) 9 10 6 ft 3 ), and the engine performance is
5,000-6,500 kW (6,711-8,725 HP). The refrigerator cools 5,000-
10,000 m 3 ((0.179-0.357) 9 10 6 ft 3 ) gas per hour on average at the
temperature of -164C charging the liquid gas containers for 8-12 h

Passenger ships Passenger ships range in size from small ferries to large cruise ships [ 62 ].

Ferries move passengers and vehicles on short trips. Ocean liners carried
passengers on one-way trips in the past. Cruise ships transport
passengers on round-trip voyages promoting leisure activities on-board
and in the ports. High speed ferries and warships use turbines which
resemble those of airplanes. Most passenger ships use a diesel engine

In 1982, plastics made up only 8% of an airplane. Now, complete airframes are
produced entirely from composite materials. Current plastics, made of carbon
fiber, glass fiber, or composite substances with nano tubes are on average up to
50% lighter than aluminum [ 43 ].