When should a welder change the tungsten electrode?

A welder should change the tungsten electrode when it burns back to the collet because this indicates a significant issue with the electrode’s integrity and performance. Burning back occurs when the end of the tungsten electrode deteriorates due to excessive heat, likely from improper arc length or incorrect current settings. If this happens, it not only affects the quality of the welds produced but also can cause contamination in the weld pool, as the melted tungsten can introduce impurities into the weld. Maintaining the integrity of the electrode is crucial for achieving clean and high-quality welds, thus necessitating a prompt change whenever this condition occurs.

While unstable arc length and visible signs of welding damage may also require attention to the electrode, these are less definitive indicators compared to the critical state of burning back to the collet, which is a clear signal that replacement is necessary to ensure effective and quality welding practices.