Welding is a process using heat or pressure to join together materials such as metal or plastic. This is a common way to join metals, and is used in the production of many goods, including automobiles, ships, trains, buildings, and bridges. Though similar to the acts of soldering and brazing, welding is distinguished from these other methods in that a weld melts the metals together, while soldering introduces a softer substance that is melted and then used to hold the original pieces together without actually melting them.
Welding has developed greatly since its conception thousands of years ago. Thanks to modern technologies, welders work with much greater precision and weld stronger welds than in the pre-19th century, when forge welding was the only technology and metals were welded by blacksmiths beating them together over hot coals. The first World War created a surge forward in welding technologies,Ugg Jimmy Choo Kalia, as the many countries looked into better and more efficient ways of welding ships and planes for the war. As welding technology has increased, welding as become more robust and can now be performed by hand or automated by machines and even robots. Welding can be performed in a variety of environments, including under water, and welding equipment can be very portable. Despite these advances, welding remains dangerous, with risk to the welder of burns, exposure to poisonous gases and eye damage.
Today some of the more common methods of welding include gas welding, arc welding, resistance welding, spot welding, electron beam welding, laser welding,black uggs cheap, and robot welding.
Gas welding, properly called "oxy-fuel welding," and commonly referred to as "oxyacetylene welding," is a process in which gas an oxygen are mixed to produce a high enough temperature at the torch to melt the edges of the metal being worked with. Thus oxy-fuel welding typically requires two tanks, one of oxygen, and another for the fuel being used. This is one of the oldest techniques for welding, and is still commonly used, in part because the equipment is easily portable. It is no longer commonly used in industrial welding, but is still often used for basic welds such as welding pipes together.
Arc welding is performed by creating an arc of electrical current between an electrode and the material being welded so as to attach the materials by melting them together. Arc welding is commonly used in industrial applications because of its low cost. A common problem with arc welds is that the oxygen and nitrogen in the atmosphere can cause welds to be brittle and weak. This is overcome by introducing shielding gasses such as hydrogen, argon, and helium.
Resistance welding uses physical pressure combined with heat produced by the resistance of electrical current passing through the materials being welded. Resistance welding melts just enough of the materials to join them together when they are put under physical pressure. This method is popular because it is easily automated and economical at a high rate of production, though initial equipment cost can make this method cost prohibitive at lower production rates.
Spot welding is a specialized form of resistance welding (see above) used to join up to four sheets of metal together. In spot welding two electrodes are used to clamp metal sheets, applying pressure and passing current through them. This method is easily automated and energy effiecient, making it popular for industrial applications,ugg australia clearance sale, particularly in automotive assembly.
Electron beam welding bombards the materials being welded with a beam of high velocity electrons, the impact of which produces heat, melting the materials and welding them together. The electrons are produced by heating a hot cathode emitter made of tungsten. This method is very precise, and used in the production of aerospace and semiconductor parts.
Laser beam welding makes use of a laser to join multiple pieces of metal together via its concentrated heat source. This method is both precise and powerful, with little heat escaping the specific welding zone, and the laser able to send heat deep into the metals welded. Laser beam welding is commonly automated and used in industrial applications such as automotive assembly.
Robot welding does not employ a different welding technique, but is distinct because of its level of automation. Robot welding is the latest technology in welding automation, and is able to perform all steps in welding, including the preparation and handling of materials. This is what sets robot welding apart from automated welding, in which a human operator is still required to prepare materials and run the automated machines. Robot welding is used in high volume production operations, such as automobile assembly.
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