Built-up Gun
A built-up gun is artillery with a specially reinforced barrel. An inner tube of metal stretches within its elastic limit under the pressure of confined powder gases to transmit stress (mechanics), stress to outer cylinders that are under tension.Fairfield (1921) p.161 Concentric metal cylinders or wire windings are assembled to minimize the weight required to resist the pressure of powder gases pushing a projectile out of the barrel. Built-up construction was the norm for guns mounted aboard 20th century dreadnoughts and contemporary railway guns, coastal artillery, and siege guns through World War II. Background The first built-up gun was designed by French artillery officer Alfred Thiéry in 1834 and tested not later than 1840. Also about 1840 another one was made by Daniel Treadwell, and yet another one was produced by Mersey Iron Works in Liverpool according to the John Ericsson's design. Sheffield architector John Frith received a patent on their manufacture in 1843. Howev ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Elastic Limit
In materials science and engineering, the yield point is the point on a stress–strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. For most metals, such as aluminium and cold-worked steel, there is a gradual onset of non-linear behavior, and no precise yield point. In such a case, the offset yield p ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Krupp Gun
Friedrich Krupp AG Hoesch-Krupp (formerly Fried. Krupp AG and Friedrich Krupp GmbH), trading as Krupp, was the largest company in Europe at the beginning of the 20th century as well as Germany's premier weapons manufacturer during both world wars. It produced battleships, U-boats, tanks, howitzers, guns, utilities, and hundreds of other commodities. The company also produced steel used to build railroads in the United States and to cap the Chrysler Building. After the Nazis seized power in Germany, Krupp supported the regime and was one of many German businesses that profited from slave labor during World War II. Upon the war's end, the head of the company, Alfried Krupp, was tried and convicted as a war criminal for employing prisoners of war, foreign civilians and concentration camp inmates under inhumane conditions in support of the Nazi war effort. Despite being sentenced to imprisonment for twelve years, he served just three and was pardoned (but not acquitted) b ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Naval Artillery
Naval artillery is artillery mounted on a warship, originally used only for naval warfare and then subsequently used for more specialized roles in surface warfare such as naval gunfire support (NGFS) and anti-aircraft warfare (AAW) engagements. The term generally refers to powder-launched projectile-firing weapons and excludes self-propelled projectiles such as torpedoes, rockets, and missiles and those simply dropped overboard such as depth charges and naval mines. Origins The idea of ship-borne artillery dates back to the classical era. Julius Caesar wrote about the Roman navy's usage of ship-borne catapults against Celtic Britons ashore in his ''Commentarii de Bello Gallico''. The dromons of the Byzantine Empire carried catapults and Greek fire. From the Middle Ages onwards, warships began to carry cannons of various calibres. In the Battle of Tangdao in 1161, the Southern Song general Li Bao used huopao (a type of gunpowder weapons, possibly cannons) and fire arro ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Hoop Gun
A hoop gun is a gun production technique that uses multiple layers of tubes to form a built-up gun. The innermost tube has one or more extra tubes wrapped around the main tube. These outer tubes are preheated before they are slid into position. As the outer tubes cool they naturally contract A contract is an agreement that specifies certain legally enforceable rights and obligations pertaining to two or more parties. A contract typically involves consent to transfer of goods, services, money, or promise to transfer any of thos .... This pre-stresses the main tube so it can withstand greater internal pressures. ReferencesUS Navy 14-inch Gun Firearm construction {{gun-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Hydraulic Fluid
A hydraulic fluid or hydraulic liquid is the medium by which power is transferred in hydraulic machinery. Common hydraulic fluids are based on mineral oil or water. Examples of equipment that might use hydraulic fluids are excavators and backhoes, hydraulic brakes, power steering systems, automatic transmissions, garbage trucks, aircraft flight control systems, lifts, and industrial machinery. Hydraulic systems like the ones mentioned above will work most efficiently if the hydraulic fluid used has zero compressibility. Functions and properties The primary function of a hydraulic fluid is to convey power. In use, however, there are other important functions of hydraulic fluid such as protection of the hydraulic machine components. The table below lists the major functions of a hydraulic fluid and the properties of a fluid that affect its ability to perform that function: Composition Base stock The original hydraulics fluid, dating back to the time of ancient Egyp ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Autofrettage
Autofrettage is a work-hardening process in which a pressure vessel (thick walled) is subjected to enormous pressure, causing internal portions of the part to plastic yield, yield plastically, resulting in internal compressive residual stresses once the pressure is released. The goal of autofrettage is to increase the pressure-carrying capacity of the final product. Inducing residual compressive stresses into materials can also increase their resistance to stress corrosion cracking; that is, non-mechanically assisted cracking that occurs when a material is placed in a corrosive environment in the presence of tensile stress. The technique is commonly used in manufacture of high-pressure pump cylinders, warship and gun barrels, and fuel injection systems for diesel engines. Due to work-hardening process it also enhances wear life of the barrel marginally. While autofrettage will induce some work hardening, that is not the primary mechanism of strengthening. The start point is a si ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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British Ordnance Terms
This article explains terms used for the British Armed Forces' Materiel, ordnance (weapons) and ammunition. The terms may have different meanings depending on their usage in another country's military. BD Between decks: applies to a naval gun mounting in which part of the rotating mass is below the deck, and part of it is above the deck. This allows for a lower profile for a gun turret, turret, meaning that the turrets need not be superfiring (i.e. they can be mounted on the same deck and not obstruct each other at high angles of elevation). BL The term BL, in its general sense, stood for breech loading, and contrasted with muzzle loading. The shell was loaded via the breech (i.e. the gunner's end of the barrel, which opened) followed by the propellant charge, and the breech mechanism was closed to seal the chamber. Breech loading, in its formal British ordnance sense, served to identify the gun as the type of Rifled breech-loader, rifled breechloading gun for which the powder c ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Butt Joint
A butt joint is a joinery, wood joint in which the end of a piece of material is simply placed (or “butted”) against another piece. The butt joint is the simplest joint. An unreinforced butt joint is also the weakest joint, as it provides a limited surface area for gluing and lacks any mechanical interlocking to resist external forces. Nonetheless, it generally provides sufficient strength in most cases, particularly when fasteners are used. Additional reinforcement through Tie (engineering), ties and plates is often used to improve the characteristics of butt-jointed structures. The joint is widely used in many applications due to its simplicity, notably in rough carpentry and construction. Methods There are several types of butt joint based on the orientation of the pieces being joined. These include the T-butt, end-to-end butt, Miter butt and edge-to-edge butt. The T-butt joint is a very simple joint to construct. Members are simply docked (cut off) at a right angle and ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Lap Joint
A lap is a surface (usually horizontal) created between the knee and hips of a biped when it is in a seated or lying down position. The lap of a parent or loved one is seen as a physically and psychologically comfortable place for a child to sit. In some countries where Christmas is celebrated, it has been a tradition for children to sit on the lap of a person dressed as Santa Claus to tell Santa what they want for Christmas, and have their picture taken, but this practice has since been questioned in some of these countries, where this sort of contact between children and unfamiliar adults raises concerns. Among adults, a person sitting on the lap of another usually indicates an intimate or romantic relationship between the two; this is a factor in the erotic activity in strip clubs known as a lap dance, where one person straddles the lap of the other and gyrates their lower extremities in a provocative manner. A lap steel guitar is a type of steel guitar played in a sitting ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Breechblock
A breechblock (or breech block) is the part of the firearm action that closes the breech of a breech loading weapon (whether small arms or artillery) before or at the moment of firing. It seals the breech and contains the pressure generated by the ignited propellant. Retracting the breechblock allows the chamber to be loaded with a cartridge. Breechblocks are categorised by the type or design of the mechanism by which it is locked or closed for firing. The firearm action more fully refers to the mechanism by which the operator actuates the opening and closing of the breech. Variants A way of closing the breech or chamber is an essential part of any breech-loading weapon or firearm. Perhaps the simplest way of achieving this is a break-action, in which the barrel, forestock and breech pivot on a hinge that joins the front assembly to the rear of the firearm, incorporating the rear of the breech, the butt and usually, the trigger mechanism. A breechblock is a separate ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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38 Cm Geschützrohr Hanstholm '', 2001
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38 may refer to: *38 (number) *38 BC *AD 38 *1938 *2038 Science * Strontium, an alkaline earth metal in the periodic table * 38 Leda, an asteroid in the asteroid belt Other uses *.38, a caliber of firearms and cartridges ** .38 Special, a revolver cartridge *'' Thirty-Eight: The Hurricane That Transformed New England'', a 2016 book by Stephen Long *"Thirty Eight", a song by Karma to Burn from the album ''Almost Heathen ''Almost Heathen'' is the third studio album by the stoner rock band Karma to Burn. It was released on September 4, 2001, by Spitfire Records. It was the last album released before their seven-year disbandment in 2002. The album was reissued in ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Deformation (mechanics)
In physics and continuum mechanics, deformation is the change in the shape (geometry), shape or size of an object. It has dimension (physics), dimension of length with SI unit of metre (m). It is quantified as the residual displacement (geometry), displacement of particles in a non-rigid body, from an configuration to a configuration, excluding the body's average translation (physics), translation and rotation (its rigid transformation). A ''configuration'' is a set containing the position (geometry), positions of all particles of the body. A deformation can occur because of structural load, external loads, intrinsic activity (e.g. muscle contraction), body forces (such as gravity or electromagnetic forces), or changes in temperature, moisture content, or chemical reactions, etc. In a continuous body, a ''deformation field'' results from a Stress (physics), stress field due to applied forces or because of some changes in the conditions of the body. The relation between stre ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |