What is the common technique to control post purge time?

The technique that is commonly used to control post purge time in Gas Tungsten Arc Welding (GTAW) is through automatic control on the power source. This method allows for precise regulation of the post purge duration, which is critical for ensuring that the tungsten electrode and the weld area are adequately protected from contamination by atmospheric gases after welding is completed.

Automatic control systems can be programmed to initiate post purge effectively, maintaining the flow of shielding gas precisely for a set period. This guarantees optimal protection for the weld, minimizing the risk of defects such as oxidation or contamination when the arc is extinguished. The integration of such controls in modern welding power sources enhances the consistency and quality of the welds produced.

While other methods such as manual adjustments or timers can be utilized, they may not provide the same level of accuracy and reliability as automatic control features built into the power source. Therefore, using automatic control for regulating post purge time is the most effective and dependable method in GTAW applications.