Gas tungsten arc welding (GTAW), also known as tungsten inert gas (TIG) welding, is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. The weld area and electrode are protected from oxidation or other atmospheric contamination by an inert shielding gas (argon or helium). A filler metal is normally used, though some welds, known as autogenous welds, or fusion welds do not require it. When helium is used, this is known as heliarc welding. A constant-current welding power supply produces electrical energy, which is conducted across the arc through a column of highly ionized gas and metal vapors known as a plasma. GTAW is most commonly used to weld thin sections of stainless steel and non-ferrous metals such as aluminum, magnesium, and copper alloys. The process grants the operator greater control over the weld than competing processes such as shielded metal arc welding and gas metal arc welding, allowing for stronger, higher quality welds. However, GTAW is comparatively more complex and difficult to master, and furthermore, it is significantly slower than most other welding techniques. A related process, plasma arc welding, uses a slightly different welding torch to create a more focused welding arc and as a result is often automated.
Rugby is a market town in Warwickshire, England, close to the River Avon. The town has a population of 70,628 (2011 census) making it the second-largest town in the county. The town is the main settlement within the larger Borough of Rugby which has a population of 100,500 (2011 census).
Rugby is on the eastern edge of Warwickshire, near the borders of Leicestershire and Northamptonshire. It is 83 miles (134 km) north of London, 30 miles (48 km) east-southeast of Birmingham, 11 miles (18 km) east of Coventry, and 19 miles (31 km) south southwest of Leicester.
Rugby was a small rural market town until the mid-19th century, when the siting of a major railway junction at the town spurred the development of manufacturing and engineering industry, and the rapid growth of population.
Rugby School, an independent school situated in the town, is the birthplace of Rugby football, which according to legend, was invented in 1823, by a Rugby schoolboy William Webb Ellis. The school was founded in 1567, and rose to national prominence as a public school in the 18th century.