What are the two main FCAW categories, and how do they differ in shielding?

What are the two main FCAW categories, and how do they differ in shielding?

• A. FCAW-G (gas-shielded) uses external shielding gas; FCAW-S (self-shielded) uses flux to shield the weld
• B. FCAW-G uses flux; FCAW-S uses external shielding gas
• C. FCAW-G uses external shielding gas; FCAW-S uses flux to shield the weld
• D. Neither uses shielding gas

Answer: (C)

Two main FCAW categories are gas-shielded and self-shielded. Gas-shielded FCAW uses shielding gas supplied from an external cylinder to protect the arc and the molten weld pool from the atmosphere, helping improve arc stability and reduce porosity. Self-shielded FCAW relies on the flux inside the tubular electrode to generate protective gases and a slag cover, so no external shielding gas is used—making it useful when gas supply or windy conditions make gas shielding impractical. The statement describing external shielding gas for the gas-shielded category and flux-based shielding for the self-shielded category correctly captures this distinction.

Two main FCAW categories are gas-shielded and self-shielded. Gas-shielded FCAW uses shielding gas supplied from an external cylinder to protect the arc and the molten weld pool from the atmosphere, helping improve arc stability and reduce porosity. Self-shielded FCAW relies on the flux inside the tubular electrode to generate protective gases and a slag cover, so no external shielding gas is used—making it useful when gas supply or windy conditions make gas shielding impractical. The statement describing external shielding gas for the gas-shielded category and flux-based shielding for the self-shielded category correctly captures this distinction.