The Port of London today
|New types of ships|
The rise of specialist ships
Some items, such as certain forestry products, still need to be packed in the traditional way, but most other goods are now carried in specialist ships.
Liquid bulk carriers
Giant supertankers carrying huge quantities of crude oil are probably the best known and most recognisable of all merchant ships.
The category also includes vessels designed to carry refined oil products and many other chemicals and vegetable oils.
When crude oil was first shipped around the middle of the 19th century, it was transported in barrels or in special tins.
The first ocean-going tanker built to carry oil in bulk was the Gluckauf (1886). Her large tanks could be filled or emptied using a pump. At 2300 tons she was tiny compared to the modern giants.
The biggest ship ever built is the 564,000 DWT Seawise Giant (1979). 485 metres (1591 feet) long, she can carry more than 4 million barrels of crude oil. The giant crude carriers specialize in long-distance trade between the Gulf and the west or Japan. Smaller tankers remain in use for shorter routes.
A basic definition of dry bulk is any solid that is shipped without packing. The dry bulk carrier evolved from the ideas of Ole Skaarup.
He proposed a vessel with its machinery at the stern, and large, clear holds with wide hatch openings for easy cargo handling. The ship, the 19,000 DWT Cassiopeia, was launched in 1955. All bulk carriers since have followed her basic design.
Dry bulk carriers, also known as 'bulkers', now play a vital role in sea-borne trade, carrying goods such as coal, grain, iron ore, aggregates (quarried or sea-dredged stone and sand) and scrap metal.
They have grown since the days of the Cassiopeia. Some are almost as big as the supertankers. The 365,000 DWT Berge Stahl, built to carry iron ore, is 360 metres (1181 feet) long.
Containerization is the practice of carrying freight in containers of uniform shape and size for shipping.
Almost anything can be stored in a container, but they are particularly useful for the transport of manufactured goods.
Since the 1950s containers have revolutionised sea-borne trade, and now carry around 90% of all manufactured goods shipped by sea.
The modern container ship evolved from the ideas of Malcolm McLean, a truck operator from North Carolina who had branched out into shipping. He found that containers simplified the loading and unloading of ships.
Advantages of containers
The traditional teams of stevedores and porters became redundant, and large quantities of goods could be shifted far more quickly than before.
With fewer workers to be paid and less time spent in the ports, containerization meant huge savings for the shipping firms.
To make containerization pay, new ships were designed. They were built to carry the maximum number of containers. Their internal layout allowed easy removal of the containers by crane.