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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 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 single steel tube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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 single steel tube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Overwrapped Pressure Vessel
A composite overwrapped pressure vessel (COPV) is a vessel consisting of a thin, non-structural liner wrapped with a structural fiber composite, designed to hold a fluid under pressure. The liner provides a barrier between the fluid and the composite, preventing leaks (which can occur through matrix microcracks which do not cause structural failure) and chemical degradation of the structure. In general, a protective shell is applied for protective shielding against impact damage. The most commonly used composites are fiber reinforced polymers (FRP), using carbon and kevlar fibers. The primary advantage of a COPV as compared to a similar sized metallic pressure vessel is lower weight; COPVs, however, carry an increased cost of manufacturing and certification. Overview A composite overwrapped pressure vessel (COPV) is a pressure-containing vessel, typically composed of a metallic liner, a composite overwrap, and one or more bosses. They are used in spaceflight due to their high ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franz Von Uchatius
Franz von Uchatius (1811–1881) was an Austrian artillery general and inventor. His inventions included both military applications and pioneer work in cinematography. He invented a motion picture projector in 1853, developing it over the years from 1845 from the device then called stroboscope (Simon von Stampfer) and phenakistiscope (Joseph Plateau). This was the first example of projected animation, demonstrated in 1853; it is also described as the combination of the zoetrope with the magic lantern. It was called the kinetoscope, a term later used by Thomas Edison (see kinetoscope). He applied it to lecture on ballistics. He worked also on a smokeless powder, was produced industrially, by mixing granulated pig iron with iron oxide. His balloons, were the earliest recorded use of an unmanned aerial vehicle for warfighting occurred on July 1849, serving as a balloon carrier (the precursor to the aircraft carrier) [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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. However, all these guns (w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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. However, all these guns (w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and even by industry. Further, both spellings are often used ''within'' a particular industry or country. Industries in British English-speaking countries typically use the "gauge" spelling. is the pressure relative to the ambient pressure. Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customary systems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as of this. Manometric u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shot Peening
Shot peening is a cold working process used to produce a compressive residual stress layer and modify the mechanical properties of metals and composites. It entails striking a surface with shot (round metallic, glass, or ceramic particles) with force sufficient to create plastic deformation."Shot Peening," ''Tool and Manufacturing Engineers Handbook'' (TMEH), Volume 3, Society of Manufacturing Engineers, 1985 In machining, shot peening is used to strengthen and relieve stress in components like steel automobile crankshafts and connecting rods. In architecture it provides a muted finish to metal. Shot peening is similar mechanically to sandblasting, though its purpose is not to remove material, but rather it employs the mechanism of plasticity to achieve its goal, with each particle functioning as a ball-peen hammer. Details Peening a surface spreads it plastically, causing changes in the mechanical properties of the surface. Its main application is to avoid the propagation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. In some materials, such as aluminium, there is a gradual onset of non-linear behavior, making the precise yield point difficult to determine. In such a case, the offset yiel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avant La Lettre
Many words in the English vocabulary are of French origin, most coming from the Anglo-Norman spoken by the upper classes in England for several hundred years after the Norman Conquest, before the language settled into what became Modern English. English words of French origin, such as ''art'', ''competition'', ''force'', ''machine'', and ''table'' are pronounced according to English rules of phonology, rather than French, and are commonly used by English speakers without any consciousness of their French origin. This article, on the other hand, covers French words and phrases that have entered the English lexicon without ever losing their character as Gallicisms: they remain unmistakably "French" to an English speaker. They are most common in written English, where they retain French diacritics and are usually printed in italics. In spoken English, at least some attempt is generally made to pronounce them as they would sound in French; an entirely English pronunciation is re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Boston Iron Company
Cyrus Alger (11 November 1781, in West Bridgewater, Massachusetts – 4 February 1856, in Boston) was a United States arms manufacturer and inventor. Biography Early in life Alger became an iron founder, training in one of his father's three foundries in the Boston area, in Easton, Massachusetts. In 1809, he worked with Thomas Handasyd Perkins, likely tied to Perkins's interest in the Monkton Iron Works in Vergennes, Vermont. Initially Monkton aimed to provide iron to American consumers while the Embargo stymied foreign competition. While the Embargo's end threatened business, the War of 1812 created a new market for Monkton. The company supplied the American government with large numbers of cannon balls as well as iron to join the timbers in constructing frigates. In 1817 Alger incorporated the South Boston Iron Company in Dorchester, Massachusetts. Through his firm's success, the region became a hub for iron manufacturing. Alger was one of the best practical metallurgists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
