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Ballast Tank
A ballast tank is a Compartment (ship), compartment within a boat, ship or other floating structure that holds water, which is used as ballast to provide hydrostatic stability for a vessel, to reduce or control buoyancy, as in a submarine, to correct Trim (vessel), trim or Angle of list, list, to provide a more even load distribution along the hull to reduce structural Hogging and sagging, hogging or sagging stresses, or to increase Draft (hull), draft, as in a semi-submersible vessel or platform, or a SWATH, to improve seakeeping. Using water in a tank provides easier weight adjustment than the stone or iron ballast used in older vessels, and makes it easy for the crew to reduce a vessel's Draft (hull), draft when it enters shallower water, by temporarily pumping out ballast. Airships use ballast tanks mainly to control buoyancy and correct trim. History The concept of ballast tanks, inspired by nature, can be seen in aquatic life forms like blowfish and the argonaut octopus, ...
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Ballast Tank Boat Cross Section
Ballast is density, dense material used as a weight (object), weight to provide stability to a vehicle or structure. Ballast, other than cargo, may be placed in a vehicle, often a ship or the Gondola (airship), gondola of a balloon (aircraft), balloon or airship, to provide Ship stability, stability. A compartment within a boat, ship, submarine, or other floating structure that holds water is called a ballast tank. Water should be moved in and out from the ballast tank to balance the ship. In a vessel that travels on the water, the ballast will be kept below the water level, to counteract the effects of weight above the water level. The ballast may be redistributed in the vessel or disposed of altogether to change its effects on the movement of the vessel. History The basic concept behind the ballast tank can be seen in many forms of aquatic life, such as the blowfish or members of the Argonaut (animal), argonaut group of octopus. The concept has been invented and reinvented man ...
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Abraham Lincoln
Abraham Lincoln (February 12, 1809 – April 15, 1865) was the 16th president of the United States, serving from 1861 until Assassination of Abraham Lincoln, his assassination in 1865. He led the United States through the American Civil War, defeating the Confederate States of America and playing a major role in the End of slavery in the United States, abolition of slavery. Lincoln was born into poverty in Kentucky and raised on the American frontier, frontier. He was self-educated and became a lawyer, Illinois state Illinois House of Representatives, legislator, and U.S. representative. Angered by the Kansas–Nebraska Act of 1854, which opened the territories to slavery, he became a leader of the new History of the Republican Party (United States), Republican Party. He reached a national audience in the Lincoln–Douglas debates, 1858 Senate campaign debates against Stephen A. Douglas. Lincoln won the 1860 United States presidential election, 1860 presidential election, wh ...
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Caisson (lock Gate)
A caisson is a form of lock gate. It consists of a large floating wrought iron, iron or steel box. This can be flooded to seat the caisson in the opening of the dock to close it, or pumped dry to float it and allow it to be towed clear of the dock. Chevron gates Most lock (water transport), locks are closed by chevron or mitre gates rather than by caissons. These are pairs of hinged gates that form a "V" shape, with the deeper water outside the V. Water pressure thus holds them closed. These gates can be opened and closed quickly, so they are used for canal locks, to change levels, and also for most freight impounded dock, docks. As the function of a freight dock is to ''enclose'' deep water, such gates point inwards. A graving dock, graving or dry dock, in contrast, ''excludes'' water, and so their gates point outwards. Hinged gates are relatively complicated, and so expensive, to construct. Large gates require powered machinery to operate them, machinery that must be provide ...
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Floating Wind Turbine
A floating wind turbine is an offshore wind turbine mounted on a floating structure that allows the turbine to generate electricity in water depths where fixed-foundation turbines are not economically feasible. Floating wind farms have the potential to significantly increase the sea area available for offshore wind farms, especially in countries with limited shallow waters, such as Spain, Portugal, Japan, France and the United States' West Coast. Locating wind farms further offshore can also reduce visual pollution, provide better accommodation for fishing and shipping lanes, and reach stronger and more consistent winds. Commercial floating wind turbines are mostly at the early phase of development, with several single turbine prototypes having been installed since 2007, and the first farms since 2017. , there are 245 MW of operational floating wind turbines, with a future pipeline of 266 GW around the world. The Hywind Tampen floating offshore wind farm, recognized ...
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Oil Platform
An oil platform (also called an oil rig, offshore platform, oil production platform, etc.) is a large structure with facilities to extract and process petroleum and natural gas that lie in rock formations beneath the seabed. Many oil platforms will also have facilities to accommodate the workers, although it is also common to have a separate accommodation platform linked by bridge to the production platform. Most commonly, oil platforms engage in activities on the continental shelf, though they can also be used in lakes, inshore waters, and inland seas. Depending on the circumstances, the platform may be fixed to the ocean floor, consist of an artificial island, or float. In some arrangements the main facility may have storage facilities for the processed oil. Remote subsea wells may also be connected to a platform by flow lines and by umbilical connections. These sub-sea facilities may include one or more subsea wells or manifold centres for multiple wells. Offshore drillin ...
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Offshore Structures (Britain) Ltd
Offshore construction is the installation of structures and facilities in a marine environment, usually for the production and transmission of electricity, oil, gas and other resources. It is also called maritime engineering. Construction and pre-commissioning is typically performed as much as possible onshore. To optimize the costs and risks of installing large offshore platforms, different construction strategies have been developed. One strategy is to fully construct the offshore facility onshore, and tow the installation to site floating on its own buoyancy. Bottom founded structure are lowered to the seabed by de-ballasting (see for instance Condeep or Cranefree), whilst floating structures are held in position with substantial mooring systems. The size of offshore lifts can be reduced by making the construction modular, with each module being constructed onshore and then lifted using a crane vessel into place onto the platform. A number of very large crane vessels w ...
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Aircraft Principal Axes
An aircraft in flight is free to rotate in three dimensions: '' yaw'', nose left or right about an axis running up and down; ''pitch'', nose up or down about an axis running from wing to wing; and ''roll'', rotation about an axis running from nose to tail. The axes are alternatively designated as ''vertical'', ''lateral'' (or ''transverse''), and ''longitudinal'' respectively. These axes move with the vehicle and rotate relative to the Earth along with the craft. These definitions were analogously applied to spacecraft when the first crewed spacecraft were designed in the late 1950s. These rotations are produced by torques (or moments) about the principal axes. On an aircraft, these are intentionally produced by means of moving control surfaces, which vary the distribution of the net aerodynamic force about the vehicle's center of gravity. Elevators (moving flaps on the horizontal tail) produce pitch, a rudder on the vertical tail produces yaw, and ailerons (flaps on the wings t ...
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British English
British English is the set of Variety (linguistics), varieties of the English language native to the United Kingdom, especially Great Britain. More narrowly, it can refer specifically to the English language in England, or, more broadly, to the collective dialects of English throughout the United Kingdom taken as a single umbrella variety, for instance additionally incorporating Scottish English, Welsh English, and Northern Irish English. Tom McArthur (linguist), Tom McArthur in the Oxford English Dictionary, Oxford Guide to World English acknowledges that British English shares "all the ambiguities and tensions [with] the word 'British' and as a result can be used and interpreted in two ways, more broadly or more narrowly, within a range of blurring and ambiguity". Variations exist in formal (both written and spoken) English in the United Kingdom. For example, the adjective ''wee'' is almost exclusively used in parts of Scotland, north-east England, Northern Ireland, Ireland ...
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Diving Plane
Diving planes, also known as hydroplanes, are control surfaces found on a submarine which allow the vessel to Pitch (flight), pitch its bow and stern up or down to assist in the process of submerging or surfacing the boat, as well as controlling depth when submerged. Bow and stern planes Diving planes are usually fitted in two pairs, the ''bow (ship), bow planes'' at the front of the submarine and the ''stern planes'' at the rear. The stern planes function in much the same way as an aircraft's elevator (aircraft), elevator. As the planes are a long distance fore-and-aft from the hull's centre of buoyancy, they introduce a pitching moment. Ballast tanks within the submarine adjust buoyancy to be neutral, making the boat controllable. The position of the planes controls the pitch (aviation), pitch of the boat and, with the forward motion of the boat, this controls depth. If not carefully controlled, this could lead to a Phugoid, 'porpoising' motion whereby the planesman continua ...
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Bathyscaphe
A bathyscaphe () is a free-diving, self-propelled deep-sea submersible, consisting of a crew cabin similar to a '' Bathysphere'', but suspended below a float rather than from a surface cable, as in the classic ''Bathysphere'' design. The float is filled with gasoline because it is readily available, buoyant, and, for all practical purposes, incompressible. The incompressibility of the gasoline means the tanks can be very lightly constructed, since the pressure inside and outside the tanks equalizes, eliminating any differential. By contrast, the crew cabin must withstand a huge pressure differential and is massively built. Buoyancy at the surface can be trimmed easily by replacing gasoline in the tanks with water, because water has a greater density. Auguste Piccard, inventor of the first bathyscaphe, coined the name ''bathyscaphe'' using the Ancient Greek words (), meaning 'deep', and (), meaning 'vessel, ship'. Mode of operation To descend, a bathyscaphe floods air ta ...
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Submersible
A submersible is an underwater vehicle which needs to be transported and supported by a larger ship, watercraft or dock, platform. This distinguishes submersibles from submarines, which are self-supporting and capable of prolonged independent operation at sea. There are many types of submersibles, including both human-occupied vehicles (HOVs) and uncrewed craft, variously known as remotely operated vehicles (ROVs) or unmanned underwater vehicles (UUVs). Submersibles have many uses including oceanography, underwater archaeology, ocean exploration, tourism, underwater work, equipment maintenance and underwater search and recovery, recovery and underwater videography. History The first recorded self-propelled underwater vessel was a small oar-powered submarine conceived by William Bourne (mathematician), William Bourne (c. 1535 – 1582) and designed and built by Dutch inventor Cornelis Drebbel in 1620, with two more improved versions built in the following four years.Konstam (201 ...
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Submarine Control Surfaces2
A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or informally to refer to remotely operated vehicles and robots, or to medium-sized or smaller vessels (such as the midget submarine and the wet sub). Submarines are referred to as ''boats'' rather than ''ships'' regardless of their size. Although experimental submarines had been built earlier, submarine design took off during the 19th century, and submarines were adopted by several navies. They were first used widely during World War I (1914–1918), and are now used in many navies, large and small. Their military uses include: attacking enemy surface ships (merchant and military) or other submarines; aircraft carrier protection; blockade running; nuclear deterrence; stealth operations in denied areas when gathering intelligence and doing reconna ...
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