LAS is the iron connection by burning. The principle of welding work is to connect two parts of metal or more by using heat energy.
Welding by the method known now, began to be known at the beginning of the 20th century. As a source of heat used fire that comes from the combustion of Acetylena gas which became known as carbide welding. At that time has been developed electric welding but still rare.
In World War II, the welding process for the first time was done on a large scale. With electric weld, in a short time, the United States can make a number of class vessels with the SS Liberty ship, which is the first ship launched with a weld. Where previously the vessel was discharged, the workmanship process used a rivet ('' rivets ''). At that time, there was also the first way to test the welding results, such as the 'kerfslag' test (a sealed indentation).
The period between 1903 and 1918 was the period of welding used primarily as a way of improvement, and the most rapid development occurred during World War I (1914-1918). welding techniques proved to be applicable primarily to repair damaged vessels. Winterton reported that in 1917 there were 103 enemy ships in America that were damaged and the number of workers in welding operations increased from 8000 to 33000 during the period 1914-1918. After 1919, the use of welding as a construction and manufacturing technique began to develop by first using a copper-tungsten alloy electrode for point welding in 1920.
In the period 1930-1950 there was much improvement in the development of welding machines. The submerged submerged arc welding process which arc covered under the first flux powder was commercially used in 1934 and patented in 1935. There are now more than 50 kinds of welding processes that can be used to connect various metals and alloys.
The welding that we see today is much more complex and already very developed. Advances in welding technology were not so rapid until 1877. Prior to 1877, welding and peyolderan welding processes had been used for 3,000 years. The origin of the welding resistance begins around 1877 when Prof. Elihu Thompson started his polarity reversal experiment on a transformer coil, he got his first patent in 1885 and the first resistance resistant welding (welding) welding machine was exhibited at the American Institute Fair in 1887.
In 1889, Coffin was granted a patent for flash-butt welding that became an important blunt welding process. Zerner in 1885 introduced the carbon arc welding process using two carbon electrodes, and N.G. Slavinoff in 1888 in Russia was the first to use the process of a metal flame arc by wearing a bare electrode (without layers). Coffin who worked separately also investigated the process of metal flame arc and got American patent in 1892. In 1889, A.P. Strohmeyer introduced the concept of coated metal electrodes to remove many of the problems that arise in the use of bare electrodes.
Thomas Fletcher in 1887 used a blowing tube of hydrogen and oxygen burned, and showed that he could cut or melt the metal. On the use and development of welding technology. At this time, welding techniques have been used extensively in connecting rods in steel construction and machine construction. The wide use of this technology is due to the building and the engine made by using this connection technique becomes lighter and the manufacturing process is also simpler, so the overall cost becomes cheaper.
Based on the discovery of historical objects, it can be seen that the technique of metal grafting has been known since prehistoric times, such as gold copper alloy bridging and soldering of lead-alloy alloys. According to the information obtained it has been known and practiced in the time span from 40000 to 30000 BC. The source of thermal energy used at the time was thought to have resulted from burning wood or charcoal, but the heat generated by the combustion from the fuel was so low that the grafting technique was not further developed.
Once the electrical energy can be used easily, the welding technology progresses rapidly and becomes a cutting edge technique. Ways and welding techniques often used at the time were arc welding, resistance welding, thermal welding, and gas welding, generally created at the end of the 19th century.
Benardes used arc welding tools in 1885, with electrodes made from carbon or graphite rods. In 1892, Slavianoff was the first to use metal wire electrodes that coalesced due to the heat generated by the electric arc. Kjellberg found the quality of the connection to be better when the electrode wire is loaded with slag. In 1886, Thomson created an electric resistance welding process. Goldscmitt invented the thermite weld in 1895 and in 1901 the oxy acetylene weld was started to be used by Fouche and piccard. In 1936 Wesserman found a way of supplication that has high strength.
Advances in science and technology reached up to the 1950's, have begun to accelerate progress in welding. At this time has found new ways in welding include cold press welding, welding slag, arc welding with CO2 protector, friction welding, plasma arc welding and much more.
source: wikipedia.org and quoted from various source
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