Which welding process uses shielding gas supplied externally rather than relying on a flux coating?

• A. SMAW
• B. PAC
• C. OFC
• D. TIG

Answer: (A)

Shielding of the weld pool can come from flux on the electrode or from an external gas supply. Flux-coated electrodes generate shielding gas as the flux decomposes, which is how those welds are protected without an external gas flow. The process that uses shielding gas supplied externally around the arc and weld pool, without relying on any flux coating, is TIG. It uses a non-consumable tungsten electrode and a protective inert gas (like argon or helium) delivered from outside. The option that relies on a flux coating for shielding doesn’t fit the description of external shielding gas. So, the best match is the TIG process.