Carbon arc welding

Carbon Arc Welding (CAW) is a process which produces coalescence of metals by heating them with an arc between a nonconsumable carbon (graphite) electrode and the work-piece. It was the first arc-welding process ever developed but is not used for many applications today, having been replaced by twin carbon arc welding and other variations. The purpose of arc welding is to form a bond between separate metals. In carbon arc welding a carbon electrode is used to produce an electric arc between the electrode and the materials being bonded. This arc produces extreme temperatures in excess of 30,000°C. At this temperature the separate metals form a bond and become welded together.

Development

CAW could not have been created if not for the discovery of the electric arc by Sir Humphry Davy in 1800.

Variations

Twin carbon arc welding (TCAW) in which the arc is established between two carbon electrodes
Gas carbon arc welding (CAW-G) no longer has commercial significance. Other processes that use shielding gases have also replaced carbon arc welding such as tungsten-arc welding (GTAW, or TIG), plasma-arc welding (PAW), and atomic-hydrogen welding (AHAW). Each of these processes, including carbon arc welding, use a non consumable electrode. A filler metal is generally used to aid the bond in the workpieces.

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