Metal Inert Gas Welding Metal inert gas welding, also known as MIG, is one of two subtypes of gas metal arc welding. In MIG, an electric arc is formed between a consumable wire electrode and a metal. This causes the metal to melt and join as desired. The following paragraphs will explain how metal inert gas welding works, the history of metal inert gas welding and the tools an individual needs for the process. As the metal is being melted to form the weld, certain precautions must be taken to ensure good quality.
In order to prevent contaminants from the air from interfering with the welding process, a shielding gas is fed through the welding gun. Helium and argon are most commonly used because they are cost efficient. These shielding gases protect the area being welded from things such as oxygen and water vapors. The improper choice of this gas can cause a weld to be weak or have excessive spatter. The process of MIG welding can be done in many different ways. For instance, the process can be automatic or semi-automatic. You can also have direct current power or an alternating current to perform the job.
The process of metal inert gas welding began in the 1940’s. The Battelle Memorial Institute developed a type of weld with smaller electrodes and H. E. Kennedy discovered a way to provide constant voltage power in 1948. Individuals used it to weld aluminum and other non-ferrous metals. It was soon discovered that it provided a faster welding time than other processes and was eventually applied to steels as well. The cost of inert gas hindered the product from becoming popular until individuals began using carbon dioxide as a semi inert gas in 1953.
The process of metal inert welding didn’t become an industrial process until the late 1950’s and early 1960’s. In order to perform metal inert gas welding, an individual will need a welding gun, and electrode wire, a wire feed unit, a welding power supply and a shielding gas supply. The welding gun used for gas metal arc welding has many key parts such as a control switch, power cable, gas nozzle, and gas hose. The welder can initiate the weld by pressing the control switch, or trigger, and allowing gases to flow and an electric arc to be struck.
The gas nozzle is used to direct the shielding gas into the desired welding area. The gas hose supplies the gases to the nozzle. Sometime a water hose is also used with high heat operations so that cooling the gun is possible. The wire feed unit supplies a constant feed rate of the electrode for the weld. All of these parts, in proper working condition, will ensure safety and high success rates. In conclusion, metal inert gas welding, a common type of gas metal arc welding, has made many significant developments since its discovery in 1948.
With the correct tools, a welder can accomplish a safe, time efficient and successful weld. Today, metal inert gas welding is the most common welding procedure due to its speed and relative ease. Works Cited How to Weld – MIG Welding. (2007, September 5). Retrieved April 24, 2013, from Instructables: http://www. instructables. com/id/how-to-weld—MIG-welding/ MIG Welding History. (2009, January). Retrieved April 24, 2013, from Weld Guru: http://www. weldguru. com/mig-welding-history. html