Dry Cargo Ships
In 1950, the
world economy was still recovering from the effects of World War II and this
was reflected in the composition of the world merchant fleet. The most common
dry cargo ship of the period was the Liberty ship. These ships, based on a
British design of 1940, were built in the United States to enable the wartime
Allies to meet the huge demand for war materials.
The standardised
demand meant that the ships could be built in shipyards all over the country.
They were welded rather than riveted, which made them easier to construct
and enabled them to built in sections. Between 1941 and 1945 a total of 2,751
Liberty ships were built, the first of them being the SS Patrick Henry,
which was launched on 27 September 1941. The 250,000 parts were pre-fabricated
throughout the country in 250-ton sections and welded together in about 70
days. One Liberty ship, the SS Robert E. Peary
was built in four and a half days. A Liberty cost under $2,000,000.
The Jeremiah
O’Brien is one of only two Liberty ships still preserved today and is berthed
in San Francisco Bay.
The Robert E. Peary was built in only five days. This was largely a propaganda exercise to boost the war effort. Nevertheless, their standard design and the fact that they were welded enabled Liberty ships to built in around fifty days, far shorter than normal. Additional information can be found at: http://www.uh.edu/~pthompso/liberty1.html
The Liberty
was 441 feet long and 56 feet wide. Her three-cylinder, reciprocating steam
engine, fed by two oil-burning boilers produced 2,500 hp and a speed of 11
knots. Her five holds could carry over 9,000 tons of cargo, plus airplanes,
tanks, and locomotives lashed to its deck. Liberty ships carried a crew of
about 44.
When the war
ended, many of these ships were sold off at bargain prices to private shipowners,
many of them foreign.It has been estimated that as late as 1960 Liberty-type
ships made up around 40% of the world general cargo fleet even as late as
1960.
The London
Harmony, photographed here in 1959, was typical of the hundreds of T2 tankers
build in the United States to meet wartime demand.
National Maritime
Museum
During this period, sea borne trade
was expanding rapidly and the demand for shipping increased as a result. One
reason was the growth of industry in Japan, which has very few raw materials
and had to import steel coal, oil and other products in order to produce the
manufactured goods that were soon being sold around the world. The Liberty
ship had shown the value of a standard design and several other types were
later developed, including the SD-14. At 14,000 gt this was larger than the
Liberty ship but was still flexible enough to operate in many different trades.
But as the post-war boom continued, owners increasingly turned to specialist
ships designed for specific trades.Demand for
bulk cargoes was so great that many owners ordered ships designed solely for
this trade. For some trades speed was important. This encouraged the development
of fast ships and also favoured new cargo handling techniques that could reduce
turn-round times in port. By the 1960s many new ship types had been or were
being developed.
Container
Ships
One of the
most important ships to be developed after World War II was the container
ship. These had many advantages when it came to transporting general cargoes.
The traditional dry cargo ship was loaded with goods carried in different
forms, mostly on pallets. Every time the ship reached port, some of the cargo
had to be unloaded and new cargo had to be taken on board. This made loading
and unloading complicated and time consuming. A turn-round ion port often
took several days to complete. There was always the danger of cargo being
damaged, and pilfering was often a major problem.
Containers
enabled most of these problems to be overcome. Once the container was loaded
and sealed it could be transported by ship, truck or train with equal ease.
Land and sea transport, in short, could be fully integrated. A shipload of
containers could be loaded or unloaded in hours rather than many days, enabling
turn-round times to be greatly reduced.
Nowadays the
container concept is so widely accepted that its benefits seem obvious. In
fact, it took several years for the idea to be accepted. During the 1920s
and 1930s, for example, British railway companies had experimented with containers,
but the combination of wood and metal used to build them was so great that
they proved uneconomic.
The man usually
given the credit for the container revolution is Malcolm McLean, a road transport
operator from North Carolina in the United States. His first idea was to stack
sealed trailers (containers) on to railway trains for long distance journeys.
This idea did not initially attract much interest and in 1955 he purchased
a small tanker company and modified two of its ships to carry trailers, which
were in turn especially modified and strengthened. In 1956 the first of these
converted ships sailed from New York to Houston. On the west coast of the
United States the Matson Navigation Company was also experimenting with containers
and its ship the Hawaiian Merchant, which sailed from San Francisco to Honolulu
on 31 August 1958 can claim to be the world’s first container ship.
By the 1960s
the size of containers had been standardised at 20 feet by 8 feet by 81/2
feet. Although many containers in use today are 40 feet in length, container
ship capacity is still measured in Twenty feet Equivalent Units, or TEUs.
Standardisation was crucial to the development of container shipping. By the
early 1960s Malcolm McLean’s company had been re-named Sea-Land Service Inc.
and by the end of the decade was operation trans-Atlantic services.
By then, the
container concept had been accepted throughout the industry and the first
purpose-built cellular container ships were being built. Several shipping
companies in Europe banded together to set up specialist container shipping
companies, including Overseas Containers Ltd. (OCL) and Associated Container
Transportation (Australia) Ltd. (ACT).
Because containerisation
reduce cargo handling times so greatly, many shipping companies saw that there
would be economic advantages in increasing the speed of the ships themselves.
Sea-Land was once again a pioneer and in 1972 began operating a fleet of container
ships that could carry more than 2,000 containers at speeds of up to 33 knots,
using 500 tonnes of fuel a day. This was far higher than the speed and fuel
consumption of conventional ships and although several other companies also
opted for speed, none tried to emulate Sea-Land’s SL7 ships, mainly on grounds
of economy.
By the mid-1970s,
fuel costs had soared and speed was no longer such an advantage. Size was,
however, and shipowners concentrated on building ships that could carry more
and more containers. Today, some ships can carry 7,000 TEUs and even larger
ships could be built.
Since 1972 the number of containers
handled by the world’s ports has grown from 6.3 million to 163.7 million[1]
and this huge increase in traffic has also had a major impact on ports themselves.
Traditional ports were located close to city centres. Cargoes were loaded
onto wharves and into warehouses and from there on to trucks or railways.
Being close to the city, which often used or supplied much of what the ship
carried, was a distinct advantage.The Chesapeake
Bay was one of a number of container ships built for the Overseas Container
Line (OCL).
One of the
many advantages of containerised transport is the ability to combine road,
rail and sea transport. These photographs show a train carrying containers
in China a truck in the United States carrying a refrigerated container and
containers on board the Nedlloyd Barcelona.
But containers
needed huge amounts of land for storage and cargo handling. This could only
be found on greenfield sites outside the city centre. And since container
ships were growing bigger in size all the time, the new container terminals
were usually built down river from the old port and were connected to existing
transport systems by new road and rail links. Traditional docks and warehouses
became redundant (and were often turned into residential or business developments).
In view of the rapid increase in the
use of freight containers for the consignment of goods by sea and the development
of specialized container ships, in 1967 the International Maritime Organization
(IMO) undertook to study the safety of containerisation in marine transport.
The container itself emerged as the most important aspect to be considered.
IMO in co-operation
with the Economic Commission for Europe developed a draft convention and in
1972 the finalised convention was adopted at a conference jointly convened
by the United Nations and IMO.
The 1972 Convention
for Safe Containers, which entered into force in 1977, has two goals. One
is to maintain a high level of safety of human life in the transport and handling
of containers by providing generally acceptable test procedures and related
strength requirements that have proven adequate over the years.
The Convention
sets out procedures whereby containers used in international transport will
be safety-approved. Other Contracting States should recognize the approval,
evidenced by the safety approval plate granted by one Contracting State. The
Convention, which has been amended four times since it entered into force,
has greatly assisted the development of the container industry by providing
an internationally recognized regime for testing the containers themselves.
Container ships are bigger, more sophisticated
and far more expensive than traditional dry cargo ships. The terminals that
have grown up to service them are also extremely costly. But despite this
the container revolution has enabled transportation costs overall too be greatly
reduced. Today, transport costs account for only about 1% of the price of
consumer goods. It is often more expensive to shift goods from one side of
the United States, for example, than it is to carry them by ship across the
Pacific.[2]The container
revolution has reduced cargo handling to a matter of hours rather than days,
but it has necessitated huge investments in equipment and space.
There seems
little doubt that the container revolution will continue in the future and
will probably accelerate still further. The trend is towards ever larger ships.
A survey carried out by the International Association of Ports and Harbours
(IAPH) showed that in 1999, 446 container ships were on order, 194 of which
had a capacity of over 1,000 TEUs. Of these 29 could carry more than 5,500
TEUs. It has been predicted that by 2010, several ships with a capacity of
15,000 TEUs will be in operation. They will be up to 450 metres long, 70 metres
wide and will carry 24 rows of containers.
Container ships
on order by 1 January 1999 IAPH It is also likely that owners will build ships
that can operate at speeds of up to 26 knots. One ship, the Norasia Samantha,
has already set a new transatlantic record of over 26 knots, carrying 1,350
TEUs 2,850 nautical miles. Anything more than that could be very expensive
in terms of fuel, but speed is an advantage in container shipping because
the turn-round time in port is so short that speed at sea can reduce the total
voyage time considerably.
Top 10 container
service operators as of January 1 1999.
Source: IAPH
1999.
