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TIG WELDING

Basic principle

Onboard applications normally require welding current up to max 150 ampere direct current (DC).

The Unitor Welding Rectifiers and inverters are well suited for TIG welding. Remote control for welding current should be used, as it is a definite advantage to adjust current during welding.

Tungsten electrode

Gas shield

Filler rod

Tungsten Inert Gas (TIG) welding (also called Gas Tungsten Arc Welding GTAW) is a process that is primarily used for high quality metals such as stainless steel, Cunifer and York Albro. It is also used on thin walled plates and pipes up to 3 mm.

Heat is produced by an electric arc that is struck between a Tungsten electrode and the work piece. The electrode tip is grinded to a point to constrict the arc to a single spot on the metal surface. The arc and the electrode are shielded by an inert gas (usually Argon) that also surrounds the weld pool and prevents oxidation. A welding rod is added to the pool to produce a weld build-up. The welding rod is normally made of a metal similar to the metal being welded. The Tungsten electrode will not melt despite very high temperatures, but it will be gradually be consumed during ignition and to some extent during actual work. This is referred to as the burn-off rate. In time, it will be necessary to regrind the electrode to a point.

The TIG welding, basic principle.

All Unitor welding machines are supplied with characteristics especially suited for TlG.

4.02

Equipment set-up:

– Gas cylinder with supply to torch. – Torch connected to negative polarity of DC power source.

– Return clamp and return cable from workpiece to positive polarity

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