Welding is the most economical and efficient way to join metals permanently. Welding is very important for our economy because more than 50% of the gross national product comes from welding. There are different kinds of welding. Some processes cause sparks and others do not require extra heat. Welding can be done for various purposes outdoors, indoors and underwater, outer space.
Welders are used for various industry groups. Some of industries where welding is used is agriculture, construction, mining, bulldozers, cranes, material handling equipment, food-processing machinery, papermaking and printing equipment, textiles and office machinery.
Welding is also used in fabricated metals like pressure vessels, heat exchangers, tanks, sheet metal, prefabricated metal buildings and ornamental work. Welding is also used for transportation purpose like shipbuilding, aircraft, spacecraft, railroads, automobiles, trucks, buses, trailers and associated equipment.
Welding is also done for primary metal industries which include steel mills, iron and steel foundries, smelting and refining plants. Another group is the electrical and electronic equipment companies.
Welding is a fusion process, in which metal parts are heated to the melting point and fused together, usually with a filler of the same material melted along with the parent material. There are many types of welding processes like Oxy-acetylene Gas Welding, Arc Welding, Tungsten Inert Gas (TIG) and Metal Inert Gas (MIG).
Arc welding is mostly used for structural steel welding. Electric current that flows through a high resistance air gap generates an intense arc with temperatures ranging from 6,000 to10, 000 degrees Fahrenheit. MIG welding are mostly preferred for industrial welding applications. The two basic inert gases used for MIG are Argon and Carbon dioxide. A mixture of 75% Argon and 25% carbon dioxide is also very common.
The shielding gas that is used in TIG is Helium. This process is considered most controllable and cleanest method of welding. TIG process can weld thin, light and dissimilar materials. Soldering and Brazing are the two most common methods of joining two metals. In Soldering and brazing, parent metal is heated and the filler metal is melted into the joint where it cools. Lead based filler metals are used in soldering and brass based filler metals are used in brazing.
Uneven heating and cooling in welding operations gives rise to significant residual stresses in the vicinity of the weld. The residual stresses and discontinuities in a weld have a significant influence on the fatigue life of a part. The fatigue part of a weld is often less than the base material. Residual stresses may be removed by annealing.
Welding is not suitable for all types of metals, as some materials, such as stainless steel can get cracks when overheated. Welding has become highly automatized over the last decade, and the use of welding robots is now common place in certain industries, such as automotive manufacturing plants
Brayan Peter is an expert author for Welding Equipments, Gas Welding. He written many articles like Spot Welders, Pipe Welders, TIG Welder, MIG Welder, Plasma Cutters, Diesel Generators. For more information visit our site http://www.everlastgenerators.com. Contact him at weldings.info@gmail.com
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