Published on July 18, 2016
An oil tanker
, also known as a petroleum tanker, is a merchant ship designed for the bulk transport of oil. There are two basic types of oil tankers: the crude tanker and the product tanker.Crude tankers move large quantities of unrefined crude oil from its point of extraction to refineries.Product tankers, generally much smaller, are designed to move refined products from refineries to points near consuming markets.
Oil tankers are often classified by their size as well as their occupation. The size classes range from inland or coastal tankers of a few thousand metric tons of deadweight (DWT) to the mammoth ultra large crude carriers (ULCCs) of 550,000 DWT. Tankers move approximately 2,000,000,000 metric tons (2.2×109 short tons) of oil every year. Second only to pipelines in terms of efficiency, the average cost of oil transport by tanker amounts to only two or three United States cents per 1 US gallon (3.8 L).
Some specialized types of oil tankers have evolved. One of these is the naval replenishment oiler, a tanker which can fuel a moving vessel. Combination ore-bulk-oil carriers and permanently moored floating storage units are two other variations on the standard oil tanker design. Oil tankers have been involved in a number of damaging and high-profile oil spills. As a result, they are subject to stringent design and operational regulations.
he technology of oil transportation has evolved alongside the oil industry. Although anthropogenic use of oil reaches to prehistory, the first modern commercial exploitation dates back to James Young’s manufacture of paraffin in 1850 In the early 1850s, oil began to be exported from Upper Burma, then a British colony. The oil was moved in earthenware vessels to the river bank where it was then poured into boat holds for transportation to Britain.
In the 1860s, Pennsylvania oil fields became a major supplier of oil, and a center of innovation after Edwin Drake had struck oil near Titusville, Pennsylvania. Break-bulk boats and barges were originally used to transport Pennsylvania oil in 40-US-gallon (150 l) wooden barrels. But transport by barrel had several problems. The first problem was weight: the standard empty barrel weighed 64 pounds (29 kg), representing 20% of the total weight of a full barrel. Other problems with barrels were their expense, their tendency to leak, and the fact that they were generally used only once. The expense was significant: for example, in the early years of the Russian oil industry, barrels accounted for half the cost of petroleum production.
In 1863, two sail-driven tankers were built on England’s River Tyne. These were followed in 1873 by the first oil-tank steamer, the Vaderland, which was built by Palmers Shipbuilding and Iron Company for Belgian owners. The vessel’s use was curtailed by U.S. and Belgian authorities citing safety concerns. By 1871, the Pennsylvania oil fields were making limited use of oil tank barges and cylindrical railroad tank-cars similar to those in use today.
Modern oil tanker
The modern oil tanker was developed in the period from 1877 to 1885. In 1876, Ludvig and Robert Nobel, brothers of Alfred Nobel, founded Branobel (short for Brothers Nobel) in Baku, Azerbaijan. It was, during the late 19th century, one of the largest oil companies in the world.
Zoroaster the world’s first tanker, delivered to the Nobel brothers in Russia.
Ludvig was a pioneer in the development of early oil tankers. He first experimented with carrying oil in bulk on single-hulled barges. Turning his attention to self-propelled tankships, he faced a number of challenges. A primary concern was to keep the cargo and fumes well away from the engine room to avoid fires.Other challenges included allowing for the cargo to expand and contract due to temperature changes, and providing a method to ventilate the tanks.
The first successful oil tanker was the Zoroaster, which carried its 242 long tons of kerosene cargo in two iron tanks joined by pipes. One tank was forward of the midships engine room and the other was aft.[ The ship also featured a set of 21 vertical watertight compartments for extra buoyancy. The ship had a length overall of 184 feet (56 m), a beam of 27 feet (8.2 m), and a draft of 9 feet (2.7 m). Unlike later Nobel tankers, the Zoroaster design was built small enough to sail from Sweden to the Caspian by way of the Baltic Sea, Lake Ladoga, Lake Onega, the Rybinsk and Mariinsk Canals and the Volga River.
In 1883, oil tanker design took a large step forward. Working for the Nobel company, British engineer Colonel Henry F. Swan designed a set of three Nobel tankers. Instead of one or two large holds, Swan’s design used several holds which spanned the width, or beam, of the ship. These holds were further subdivided into port and starboard sections by a longitudinal bulkhead. Earlier designs suffered from stability problems caused by the free surface effect, where oil sloshing from side to side could cause a ship to capsize. But this approach of dividing the ship’s storage space into smaller tanks virtually eliminated free-surface problems. This approach, almost universal today, was first used by Swan in the Nobel tankers Blesk, Lumen, and Lux.
The Glückauf grounded in heavy fog at Blue Point Beach on Fire Island.
Others point to the Glückauf, another design of Colonel Swan, as being the first modern oil tanker. It adopted the best practices from previous oil tanker designs to create the prototype for all subsequent vessels of the type. It was the first dedicated steam-driven ocean-going tanker in the world and was the first ship in which oil could be pumped directly into the vessel hull instead of being loaded in barrels or drums. It was also the first tanker with a horizontal bulkhead; its features included cargo valves operable from the deck, cargo main piping, a vapor line, cofferdams for added safety, and the ability to fill a ballast tank with seawater when empty of cargo The ship was built in Britain. and was purchased by Wilhelm Anton Riedemann, an agent for the Standard Oil Company along with several of her sister ships. After the Glückauf was lost in 1893 after being grounded in fog, Standard Oil purchased the sister ships.
A Royal Dutch Petroleum dock in the Dutch East Indies (now Indonesia)
The 1880s also saw the beginnings of the Asian oil trade. The idea that led to moving Russian oil to the Far East via the Suez Canal was the brainchild of two men: importer Marcus Samuel and shipowner/broker Fred Lane. Prior bids to move oil through the canal had been rejected by the Suez Canal Company as being too risky.Samuel approached the problem a different way: asking the company for the specifications of a tanker it would allow through the canal.
Armed with the canal company’s specifications, Samuel ordered three tankers from William Gray & Company in northern England. Named the Murex, the Conch and the Clam, each had a capacity of 5,010 long tons of deadweight. These three ships were the first tankers of the Tank Syndicate, forerunner of today’s Royal Dutch Shell company.
With facilities prepared in Jakarta, Singapore, Bangkok, Saigon, Hong Kong, Shanghai, and Kobe, the fledgling Shell company was ready to become Standard Oil’s first challenger in the Asian market. On August 24, 1892, the Murex became the first tanker to pass through the Suez Canal. By the time Shell merged with Royal Dutch Petroleum in 1907, the company had 34 steam-driven oil tankers, compared to Standard Oil’s four case-oil steamers and 16 sailing tankers.
The supertanker era
Until 1956, tankers were designed to be able to navigate the Suez Canal. This size restriction became much less of a priority after the closing of the canal during the Suez Crisis of 1956.Forced to move oil around the Cape of Good Hope, shipowners realized that bigger tankers were the key to more efficient transport.While a typical T2 tanker of the World War II era was 532 feet (162 m) long and had a capacity of 16,500 DWT, the ultra-large crude carriers (ULCC) built in the 1970s were over 1,300 feet (400 m) long and had a capacity of 500,000 DWT. Several factors encouraged this growth. Hostilities in the Middle East which interrupted traffic through the Suez Canal contributed, as did nationalization of Middle East oil refineries. Fierce competition among shipowners also played a part. But apart from these considerations is a simple economic advantage: the larger an oil tanker is, the more cheaply it can move crude oil, and the better it can help meet growing demands for oil.
In 1955 the world’s largest supertanker was 30,708 GRT and 47,500 LT DWT: the SS Spyros Niarchos launched that year by Vickers Armstrongs Shipbuilders Ltd in England for Stavros Niarchos.
In 1958 United States shipping magnate Daniel K. Ludwig broke the record of 100,000 long tons of heavy displacement. His Universe Apollo displaced 104,500 long tons, a 23% increase from the previous record-holder, Universe Leader which also belonged to Ludwig.
Knock Nevis, ex Seawise Giant rivaled some of the world’s largest buildings in size
The world’s largest supertanker was built in 1979 at the Oppama shipyard by Sumitomo Heavy Industries, Ltd. as the Seawise Giant. This ship was built with a capacity of 564,763 DWT, a length overall of 458.45 metres (1,504.1 ft) and a draft of 24.611 metres (80.74 ft). She had 46 tanks, 31,541 square metres (339,500 sq ft) of deck, and at her full load draft, could not navigate the English Channel.
Seawise Giant was renamed Happy Giant in 1989, Jahre Viking in 1991, and Knock Nevis in 2004 (when she was converted into a permanently moored storage tanker).In 2009 she was sold for the last time, renamed Mont, and scrapped.
As of 2011, the world’s two largest working supertankers are the TI class supertankers TI Europe and TI Oceania. These ships were built in 2002 and 2003 as the Hellespont Alhambra and Hellespont Tara for the Greek Hellespont Steamship Corporation. Hellespont sold these ships to Overseas Shipholding Group and Euronav in 2004. Each of the sister ships has a capacity of over 441,500 DWT, a length overall of 380.0 metres (1,246.7 ft) and a cargo capacity of 3,166,353 barrels (503,409,900 l). They were the first ULCCs to be double-hulled. To differentiate them from smaller ULCCs, these ships are sometimes given the V-Plus size designation.
With the exception of the pipeline, the tanker is the most cost-effective way to move oil today. Worldwide, tankers carry some 2 billion barrels (3.2×1011 l) annually, and the cost of transportation by tanker amounts to only US$0.02 per gallon at the pump.