Sunday, August 17, 2008

Principles of Gas Tungsten Arc Welding (GTAW)

PROCESS DESCRIPTION
Gas Tungsten Arc Welding (GTAW), also known as Tungsten Inert Gas (TIG) welding is a process that produces an electric arc maintained between a non-consumable tungsten electrode and the part to be welded. The heat-affected xone, the molten metal and the tungsten electrode are all shielded from atmospheric contamination by a blanket of inert gas fed through the GTAW torvh. Inert gas (usually Argon) is inactive or deficient in active chemical properties. The shielding gas serves to blanket the weld and esclude active properties in the sorrounding air. Inert gases such as Argon and Helium do not chemically react or combine with other gases. They pose no odor and are transparent, permitting the welder maximum visibility of the arc. In some instances Hydrogen gas may be added to enhance travel speeds.
The GTAW process can produce temperatures of up to 35,000 degrees F (19,426 degrees C). The torch contributes heat only to the workpiece. If filler metal is required to make the weld, it may be added manually in the same manner as it is added in the oxyacetylene welding process.
GTAW is used to weld stainless steel, nickel alloys such as Monel and Inconel, titanium, aluminum, magnesium, copper, brass, bronze and even gold. GTAW can also weld dissimilar metals to one another such as copper to brass and stainless to mild steel.

Next topic will be: ADVANTAGES AND DISADVANTAGES OF GTAW.

ARC WELDING HAZARDS

Protect yourself and others from injury!!!!

1.) Electric shock can kill
2.) Hot parts can cause severe burns
3.) Fumes and gases can be hazardous
4.) Arc rays can burn eyes and skin
5.) Welding can cause fire or explosion
6.) Flying metal or dirt can injure eyes
7.) Build-up of gas can injure or kill
8.) Magnetic fields can affect implanted medical devices
9.) Noise can damage hearing
10.) Cylinders can explode if damaged