Purging Practices for Pipe Welding

Abstract

TIG welding process is being predominantly used in the fabrication of carbon, alloy and stainless steel pipings of various diameters in critical sections. TIG welding with consumable inserts and insert gas backing is preferred for depositing the ischolar_main bead. Argon gas is preferred in such applications as in Nuclear Steam heat exchangers due to its following properties :

1. Smoother and quieter arc action.

2. Lower arc voltage at given current value and arc length.

3. Greater cleaning action in welding.

4. Lower flow rates for good shielding.

5. Easier arc starting.