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Low Magnetic Electric Motor
A low magnetic electric motor (or non magnetic electric motor) is an AC motor, AC or DC motor with a reduced Magnetic field, magnetic stray field signature. Description Low magnetic or nonmagnetic electric motors are used on board mine countermeasures vessels, minehunters, minesweepers and specific types of submarines. For about a hundred years sea mines or naval mines have been an established element in naval warfare. Modern naval mines nowadays react on magnetic, acoustic and pressure signals. By far the most important step in their development was the invention of the magnetic influence firing principle, which utilizes the magnetic interference field of passing ships. Naval mines with magnetic fuzes are effective, inexpensive and easy to deploy. An electric motor produces two types of magnetic fields: a dynamic alternating stray field, whilst running and a static remnant or residual magnetic during standstill. To avoid detection it is necessary to reduce these signatures at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Motor
An electric motor is an Electric machine, electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a Electromagnetic coil, wire winding to generate force in the form of torque applied on the motor's shaft. An electric generator is mechanically identical to an electric motor, but operates with a reversed flow of power, converting mechanical energy into electrical energy. Electric motors can be powered by direct current (DC) sources, such as from batteries, or rectifiers, or by alternating current (AC) sources, such as a power grid, Inverter (electrical), inverters or electrical generators. Electric motors may be classified by considerations such as power source type, construction, application and type of motion output. They can be powered by AC or DC, be Brushed motor, brushed or Brushless motor, brushless, single-phase, Two-phase electric power, two-p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rolling-element Bearing
In mechanical engineering, a rolling-element bearing, also known as a rolling bearing, is a bearing which carries a load by placing rolling elements (such as balls or rollers) between two concentric, grooved rings called races. The relative motion of the races causes the rolling elements to roll with very little rolling resistance and with little sliding. One of the earliest and best-known rolling-element bearings are sets of logs laid on the ground with a large stone block on top. As the stone is pulled, the logs roll along the ground with little sliding friction. As each log comes out the back, it is moved to the front where the block then rolls on to it. It is possible to imitate such a bearing by placing several pens or pencils on a table and placing an item on top of them. See " bearings" for more on the historical development of bearings. A rolling element rotary bearing uses a shaft in a much larger hole, and cylinders called "rollers" tightly fill the space between t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tripartite-class Minehunter
The Tripartite class is a class of minehunters developed from an agreement between the navies of Belgium, France and the Netherlands. A total of 35 ships were constructed for the three navies. The class was constructed in the 1980s–1990s in all three countries, using a mix of minehunting, electrical and propulsion systems from the three member nations. In France, where they are known as the ''Éridan'' class they are primarily used as minehunters, but have been used for minesweeping and ammunition transport in Belgium and the Netherlands, where the Tripartites are known as the ''Alkmaar'' class. In 1992, the Pakistan Navy acquired three vessels from France, one that was already built, one to be built in France and one built in France and Pakistan. Known as the ''Munsif'' class, all three are still in service. The Indonesian Navy acquired two minehunters in the 1990s from the Dutch to a modified design. Known as the ''Pulau Rengat'' class, the two ships are still in service. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osprey-class Minehunter
The ''Osprey'' class are a series of coastal minehunters designed to find, classify, and destroy moored and bottom naval mines from vital waterways. Their design is based on the second series of the Italian Lerici-class, built in La Spezia by Intermarine between 1990 and 1996. Eight vessels were built in the Intermarine shipyard located in Savannah, while the remaining four have been built by a second-source shipyard under a Technology Transfer and Licence Agreement. They use sonar and video systems, cable cutters and a mine detonating device that can be released and detonated by remote control. The ''Osprey'' class are the world's second largest minehunters (surpassed by the Royal Navy's s) to be constructed entirely of fiberglass and designed to survive the shock of underwater explosions. Their primary mission is reconnaissance, classification, and neutralization of all types of moored and bottom mines in littoral areas, harbors and coastal waterways. Construction Twelve m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USS Arkansas (CGN-41) Shock Trials
USS ''Arkansas'' may refer to one of these ships of the United States Navy named in honor of the 25th state. * , a screw steamer originally named the ''Tonawanda'' that served in the American Civil War. After that war, she was renamed ''Tonowanda'', and lost off Key Largo in 1866. * , an with a single gun turret. She was one of the last monitors of the U.S. Navy, commissioned in 1902, but having her name changed to the USS ''Ozark'' in 1906. Scrapped in 1922. * , one of two s, commissioned in 1912. One of the oldest ships of World War II, she was expended and wrecked in an atomic bomb test at Bikini Atoll in July 1946, where her wreckage still lies. * , one of four nuclear-powered guided missile cruisers; commissioned in 1980 and decommissioned in 1998. * , a future nuclear-powered attack submarine An attack submarine or hunter-killer submarine is a submarine specifically designed for the purpose of attacking and sinking other submarines, surface combatants and merchant v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thales Nederland
Thales Nederland B.V. (formerly Hollandse Signaalapparaten B.V. or in short Signaal) is a subsidiary of the French multinational company Thales Group based in the Netherlands. The firm was founded as ''NV Hazemeyer's Fabriek van Signaalapparaten'' during 1922 by Hazemeyer and Siemens & Halske to produce naval fire-control systems. During the Second World War, the company's factory was captured and pillaged by the German Army; shortly after the conflict's end, the remaining assets were nationalised by the Dutch government, the company being renamed ''N.V. Hollandsche Signaalapparaten'' (or ''Signaal'' for short). During 1956, the Netherlands-based electronics company Philips became the majority owner of Signaal after buying a large portion of the shares from the government. The firm expanded throughout much the Cold War period, producing various naval electronics and defense systems for a range of customers around the world. During 1990, the French electronics and defence contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Netherlands Organisation For Applied Scientific Research
Nederlandse Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek (TNO; en, Netherlands Organisation for Applied Scientific Research) is an independent research organisation in the Netherlands that focuses on applied science. The organisation also conducts contract research, offers specialist consulting services, and grants licences for patents and specialist software. TNO tests and certifies products and services, and issues an independent evaluation of quality. Moreover, TNO sets up new companies to market innovations. Background TNO was established by law in 1932 to support companies and governments with innovative, practicable knowledge. As a statutory organisation, TNO has an independent position that allows to give objective, scientifically founded judgments. It is similar to the following: * CSIR in Ghana * CSIR in India * CSIR in South Africa * CSIRO in Australia * Fraunhofer Society in Germany * SINTEF in Norway Furthermore, TNO also held 10% of the Austrian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIL-STD-810
MIL-STD-810, U S Department of Defense Test Method Standard, Environmental Engineering Considerations and Laboratory Tests, is a United States Military Standard that emphasizes tailoring an equipment's environmental design and test limits to the conditions that it will experience throughout its service life, and establishing chamber test methods that replicate the effects of environments on the equipment rather than imitating the environments themselves. Although prepared specifically for U.S. military applications, the standard is often applied for commercial products as well. The standard's guidance and test methods are intended to: * define environmental stress sequences, durations, and levels of equipment life cycles; * be used to develop analysis and test criteria tailored to the equipment and its environmental life cycle; * evaluate equipment's performance when exposed to a life cycle of environmental stresses * identify deficiencies, shortcomings, and defects in equipment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIL-S-901
Military Specification MIL-S-901D is for high-impact mechanical shock which applies to equipment mounted on ships. Its publication date was Mar 17, 1989. Two levels apply: Grade A items are items which are essential to the safety and continued combat capability of the ship; Grade B items are items whose operation is not essential to the safety and combat capability of the ship but which could become a hazard to personnel, to Grade A items, or to the ship as a whole as a result of exposure to shock. "Grade C", signifying that no shock qualification is required, is also sometimes referenced in acquisition documents even though the term has no official standing in the specification document. Qualification testing is performed on a specified machine or on a barge floating in a pond where an explosive charge is detonated at various distances and depths in the pond to impart shock to the barges. ThMIL-S-901Dspecification covers shock testing requirements for ship board machi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock (mechanics)
A mechanical or physical shock is a sudden acceleration caused, for example, by impact, drop, kick, earthquake, or explosion. Shock is a transient physical excitation. Shock describes matter subject to extreme rates of force with respect to time. Shock is a vector that has units of an acceleration (rate of change of velocity). The unit ''g'' (or g) represents multiples of the acceleration of gravity and is conventionally used. A shock pulse can be characterised by its peak acceleration, the duration, and the shape of the shock pulse (half sine, triangular, trapezoidal, etc.). The shock response spectrum is a method for further evaluating a mechanical shock. Shock measurement Shock measurement is of interest in several fields such as *Propagation of heel shock through a runner's body *Measure the magnitude of a shock need to cause damage to an item: fragility. *Measure shock attenuation through athletic flooring *Measuring the effectiveness of a shock absorber *Measuring th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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