ABSTRACT
The tungsten arc gas-shielded (TAGS) process is also known as tungsten inert gas welding, argon arc welding and gas tungsten arc welding. TAGS and oxyacetylene welding differ slightly in that both torch and filler rod angles have to be considered. When using TAGS process, problems arise when arc initiation (striking) is achieved by touching electrode onto the work as this will cause contamination of the work and the tungsten electrode. Care should also be taken to ensure that when dipping action of filler rod takes place the end of the filler is not withdrawn from the protection of the gas shield as this may introduce impurities into the weid. AC creates a situation where it is possible to change between electrode positive and electrode negative. The footpedal can be used as an alternative to the slope up/slope down facility. To perform acceptable fusion welds the joint edges must be tightly fitted up and tacks will be closer together.
