TUNGSTEN - INERT GAS WELDING

 Tungsten-inert gas welding -: It is also known as " gas tungsten arc welding ". It is an inert gas shielded arc welding process using a non- comsumerabl electrod. The electrod may also contain 1 to 2 % of " thorium oxide " mixed along with the core tungsten or tungsten with 0.15 to 0.04 % " zirconium oxide ".

                       

The pure tungsten electrod are less-expansive but will carry less current. The zirconium added in tungsten electrod are better than the pure tungsten. A tipical tungsten inert gas welding set-up in figure. It consist of welding torch at the center of which is the tungsten electrod . The inert gas supply to the welding zone through the annular path surrounding the tungsten electrod to the effectively displayed the atmosphere around the weld puddle. The smaller weld torch may not be provided with any polling devices for the electrod.

             The tungsten inert gas arc welding process can be use for joining of number of material through the most common welding arc aluminium, magnesium and stainless steel.            

S.No.   MATERIAL              ELECTROD

 1.        Stainless steel          De-oxidize Tungsten  

 2.        Aluminium                 All types of tungsten 

 3.       Magnesium                Tungsten 

 4.       De-oxidizing copper  Toriated tungsten 

 5.      High carbon steel       Toriated tungsten 

 6.      Cast iron                       toriated tungsten