CNC Directory

TIG (tungsten metal gas) welding, also known as GTAW (gas tungsten arc welding) is an arc welding method which uses a non-consumable tungsten tip to weld in an inert gas. The procedure is known amongst welders as being the cleanest and neatest welding technique in existence, but also one of the most expensive.

TIG welding is thought by many to be the most difficult manual welding process in the industry. This is because the arc length is so short, therefore the welder must have great skill in order to prevent the electrode and the piece to be worked from touching. Therefore, TIG welding requires both hands to be used (one for the electrical supply through the tungsten electrode, and one to feed in a filler metal).

The welding arc is struck with a high frequency spark from a generator. This answers the common question asked by many about TIG welding: “If the electrode does not touch the work piece, how can the electric arc pass through air?” The spark allows the electricity to be conducted initially…it is than important to keep the tungsten electrode and the surface separate, usually by a distance of about 2mm, or the operator will have bits of filler metal all over his tungsten electrode.

When the arc is struck, the welder rotates the electrode to form a welding pool of molten metal. He can now (with the other hand) insert a filler metal into the weld, and advance the tungsten electrode. The inert gas prevents any oxidisation of filler or surface metal whilst the weld is in progress.

Of course, as with other welding processes, TIG Welding can be highly dangerous if proper precautions are not taken. Extreme ultraviolet radiation is produced, which can harm eyes and even trigger skin cancer. Sparks can often fly and little drops of molten metal can burn skin badly and even start a workshop fire, although a skilled welder will seldom produce either of these whilst TIG welding.

TIG welding is often used for the most elite of welding applications, such as aerospace, space shuttles, and high-tech scientific equipment. It is also the most common welding technique used for the bonding of more reactive metal, such as zinc, magnesium and aluminium. As the filler metal does not have to be transferred across the arc, TIG welding is also highly versatile in that a high number of filler metals can be used. Therefore, as the filler metal can match the base metal, the welds are usually stable, resistant to corrosion and maintenance-free. This makes them ideal for another high-risk use: the sealing of nuclear fuel in their canisters before disposal.

The electrode used in TIG welding is manufactured from Tungsten, a very dense metal, which more importantly, has the highest melting point of any metal and the second highest melting point of any element after carbon. This makes it ideal for welding, as it is so sturdy and stable.




part of the Livetech Group celebrating 10 years service
mini community

This is a 

powered by the minisite web design platform