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.
The Metropolitan Borough of Solihull is a metropolitan borough of the West Midlands, in west-central England. It is named after its largest town, Solihull, from which Solihull Metropolitan Borough Council is based. For Eurostat purposes it is a NUTS 3 region (code UKG32) and is one of seven boroughs or unitary districts that comprise the "West Midlands" NUTS 2 region. Much of the large residential population in the north of the borough centres on the communities of Castle Bromwich, Chelmsley Wood, Fordbridge, Kingshurst, Marston Green and Smith's Wood. In the south are the town of Solihull, its sub-town of Shirley and the large villages of Knowle, Dorridge, Meriden and Balsall Common.
Since 2011, Solihull has formed part of the Greater Birmingham & Solihull Local Enterprise Partnership along with neighbouring authorities Birmingham, Bromsgrove, Cannock Chase, East Staffordshire, Lichfield, Redditch, Tamworth and Wyre Forest.