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Frederic Logghe
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Barge Carriers
Cable Layers
A cable layer is a deep-sea vessel designed and used to lay underwater cables for telecommunications, electricity, and such.
Car Carrier Vessels
Cargo vessels
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Cargo vessels - Bulk carriers
A bulk carrier is ocean-going vessel used to transport bulk cargo items such as ore or food staples (rice, grain, etc.) and similar cargo. It can be recognized by the large box-like hatches on its deck, designed to slide outboard for loading. A bulk carrier could be either dry or wet. Most lakes are too small to accommodate bulk ships, but a large fleet of lake freighters has been plying the Great Lakes and St. Lawrence Seaway of North America for over a century.

Like the container ship, the modern bulk carrier had its roots in solving this problem of moving cargo on and off the ship efficiently. The idea originated with ship broker Ole Skaarup. In 1954 his small New York company repaired and chartered ships for bulk cargoes. He understood how inefficient the process was and imagined a new ship.

In a 1992 article in the American Bureau of Shipping?s Surveyor Magazine, Skaarup explained that to him ?It seemed the most practical ship should have wide, clear cargo holds. Thus, it would require machinery aft, wide hatch openings to ease cargo handling and a hold configuration that could eliminate the need for shifting boards. To make the hatches acceptable as grain feeders, they would have to extend several feet above deck.?

But Skaarup also wanted a safe ship, that would be stable and seaworthy. When grain or similar bulk cargoes are loaded into a ship, they tend to pile in the middle of the hold and slope down to the bulkheads. This creates area for the cargo to shift, which can cause a ship at sea to become dangerously unstable. Skaarup thought he could eliminate this problem by building a ship with sloping ballast wing tanks at the top sides of the cargo hold. These tanks would fill the void left in a conventional hold and help stabilize the ship.

He took his idea to the Swedish shipping company, Nordstrom & Thulin. They were convinced, and with help from famed industrialist Marcus Wallenberg, Skaarup?s idea became a $2.5 million 19,000 DWT shipping experiment ? the OS type design. The ship incorporated the sloped wing tanks, aft engine room and bridge, wide open cargo holds with smooth sides and sloping bulkheads. Conventional-thinking engineers at the Kockums Shipyard, where it was built, had fought with Skaarup over the lack of a centerline bulkhead and a dozen other important details, but he stood firm and the ship, called Cassiopeia, was an immediate success.

Thanks to the new features, Cassiopeia could be loaded at a cost savings of 50 cents per ton. This seemingly small figure allowed the ship to save its entire construction cost in 10 years, which is a monumental achievement in a ship designed to trade for at least 30 years. Soon other shipping companies wanted vessels like her. Today nearly 7,000 ships of the OS type have been built and they carry the vast majority of the world?s dry bulk cargoes.

As with other types of modern cargo ships, the bulk carrier has grown in size over the years. Today there are four types of bulk ships trading today (see chart below). Some of the commodities currently being moved in bulk ships include: iron ore; coal; grain; bauxite; phosphate rock; salt; cement; woodchips; and fertilizer.

Bulk Carrier Classifications:

- Handysize - 10,000 DWT - 40,000 DWT
- Handymax - 40,000 DWT - 60,000 DWT
- Panamax - 60,000 DWT - 100,000 DWT
- Capesize - 100,000 DWT - And Larger
Cargo vessels - Palletised cargo vessels
Cargo vessels - Reefers
The reefer is a type of ship typically used to transport perishable commodities which require temperature-controlled transportation, mostly fruits, meat, fish, vegetables, dairy products and other foodstuffs.

A major use of refrigerated cargo hold type ships was for the transportation of bananas but has since been partly replaced by refrigerated containers that have a refrigeration system attached to the forward end of the container. While on a ship this is plugged into a 220 VAC outlet that ties into the ships power generation. Many ships are limited by the amount of refrigeration containers they can carry due to the lack of refrigeration outlets or insufficient generator capacity. Each ?reefer? container has its own breaker switch that allows it to be connected/disconnected in adverse weather with the power off.

Refrigerated cargo is a key part of the income for a shipping company. Refrigerated containers are mostly carried above deck as they have to be checked for proper operation, they may have to have a major part such as a compressor fail which has to be replaced, or they may need to be unplugged quickly as in the event of a fire. As such, this means no provisions for refrigerated cargo power connections are made below the hatch covers that enclose the top of the hatches aboard a ship. Although modern containervessels stow the reefercontainers in cellguides with inspection walkways beside. That way reefercontainers can be and are carried in the holds as well. Some modern containervessels also incorporats a watercooling system, that enables the containers own refrigiationsystem to be disconnected, as they are rather ineffecient below deck, due to the high amount of heat they generate. This system draws freshwater from the ships watersypply, that have been cooled to a preset level.

There are also refrigeration systems that have two compressors for very precise and low temperature operation, such as transporting a container full of blood to a war zone. Containers of shrimp, caviar, and blood are among the most expensive refrigerated items. (Source: Wikipedia)
Container vessels
Container ships are cargo ships that carry all of their load in truck-size containers. Their capacity is measured in TEU (Twenty-foot Equivalent Units). This is the number of 20 ft containers that it can carry. The first container ships were converted tankers, built up from surplus tanker Liberty ships after World War II.
Cruise & passenger vessels
A passenger ship is a ship whose primary function is to carry passengers. In the latter part of the 20th century passenger ships gave way to cruise ships as the predominant form of large passenger ship.
A cruise ship is a passenger ship used for pleasure voyages, where the voyage itself and the amenities of the ship (swimming pools, theaters, ball rooms, casinos, sports facilities, etc.) are considered an essential part of the experience.
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Drilling vessels
A drillship is a maritime vessel that has been fitted with drilling apparatus. It is most often used for exploratory drilling of new oil or gas wells in deep water but can also be used for scientific drilling. It is often built on a modified tanker hull and outfitted with a dynamic positioning system to maintain its position over the well.

Drillships are able to drill in water depths of over 2000 meters. In order to drill a Marine Riser is lowered to the seabed with a Blow Out Preventer (BOP) at the bottom. Drillships are just one way to perform exploratory drilling. This function can also be performed by Semi-submersibles, jackups, barges, or platform rigs.

The first drillship was the Cuss 1. (Source: Wikipedia)
Research vessels
A research vessel is a ship primarily constructed to carry out scientific research at sea. Hydrographic survey vessels are used to conduct hydrographic and seismic surveys of the seabed and the underlying geology.
Oceanographic research vessels carry out research on the physical, chemical and biological characteristics of water, the atmosphere and climate, and as such, are required to carry equipment for collection of water samples from a range of depths, including the deep seas, as well as eqipment for hydrographic sounding of the seabed, along with numerous other environmental sensors.
Salvage vessels
Slave ships
Slave ships were cargo boats specially converted for the purpose of transporting slaves. The most important routes of the slave ships led from the northern and middle coasts of Africa to South America and the south coast of what is today the Caribbean and the USA.

In order to achieve high profits from the transports, the owners of the ships divided the hull into between decks, so they could transport as many slaves as possible. This led to indescribably unhygienic conditions, and consequently an enormously high mortality rate. Only the most resilient survived the transport. Often the ships transported hundreds of slaves, who were chained tightly to plank beds. For example, the slave ship "Henrietta Marie" carried up to 400 slaves on a single passage, who were confined to two decks, and each slave spent the week long passage chained to only one half square meter.
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Stone dumping vessels
Tankers - Gas carriers
Tankers - Gasoline tankers
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Training vessels
A school ship is a ship used for the training of students as sailors. The term is especially used of ships employed by navies to train future officers. Essentially there are two types, old hulks used to house classrooms, and those used for training at sea.
The hands on aspect provided by sail training has also been used as a platform for everything from semesters at sea for undergraduate oceanography and biology students, marine science and physical science for high school students and character building and discipling for at risk youths.
Tugs - Seagoing motor tugs
Tugs - Seagoing steam tugs

Last additions - 002s Sea & Ocean vessels
Diamond Princess in Antwerp on 21st July 2007409 viewsJul 24, 2007
Diamond Princess in Antwerp on 21st July 2007370 viewsJul 24, 2007
The Calypso, boat of Commandant Cousteau, in april 1999 in La Rochelle629 viewsJun 08, 2007
Independance796 viewsApr 23, 2007
Norway891 viewsApr 23, 2007
Maersk Sealand849 viewsApr 23, 2007
The Emerald676 viewsApr 23, 2007
Hickory765 viewsApr 23, 2007

(c) 2009 Frederic Logghe GNU Free Documentation License Birds in the sky
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