What is the proper method to remove slag after welding with SMAW or FCAW?

What is the proper method to remove slag after welding with SMAW or FCAW?

• A. Use a chipping hammer to remove slag and then brush the surface with a wire brush until clean.
• B. Grind the slag off with a grinding wheel.
• C. Wipe with solvent.
• D. Let slag peel off on its own.

Answer: (A)

After SMAW or FCAW, slag sits on the weld as a byproduct of the flux and must be removed to reveal a clean bead for inspection and, if more passes are needed, proper bonding. The best method is to chip away the slag with a chipping hammer and then brush the surface with a wire brush until clean. This mechanical removal thoroughly clears the slag without grinding away base metal or altering the heat-affected zone, and it prevents slag inclusions that could compromise weld integrity. Grinding the slag is not appropriate because it can gouge the weld, overheat the surrounding metal, or embed abrasive particles into the weld area. Wiping with solvent won’t remove slag, and letting the slag peel off on its own is unsafe because it can hide defects and interfere with subsequent welding or inspection. Always protect your eyes and hands during removal and inspect the weld once cleaned.

After SMAW or FCAW, slag sits on the weld as a byproduct of the flux and must be removed to reveal a clean bead for inspection and, if more passes are needed, proper bonding. The best method is to chip away the slag with a chipping hammer and then brush the surface with a wire brush until clean. This mechanical removal thoroughly clears the slag without grinding away base metal or altering the heat-affected zone, and it prevents slag inclusions that could compromise weld integrity. Grinding the slag is not appropriate because it can gouge the weld, overheat the surrounding metal, or embed abrasive particles into the weld area. Wiping with solvent won’t remove slag, and letting the slag peel off on its own is unsafe because it can hide defects and interfere with subsequent welding or inspection. Always protect your eyes and hands during removal and inspect the weld once cleaned.