For SMAW electrodes F3, which polarity is allowed?

For SMAW electrodes F3, which polarity is allowed?

• A. Direct polarity only
• B. Reverse polarity only
• C. AC polarity only
• D. Both AC and DC with positive

Answer: (B)

Polarity direction in SMAW affects how heat is distributed, arc stability, and how the shielding and slag behave. For this F3 electrode, the coating and chemistry are designed to work with the electrode positive (reverse polarity). This setup provides the intended arc characteristics and penetration, along with proper slag formation and deposition. Using AC or the opposite direct polarity would destabilize the arc and degrade weld quality, and would not meet the electrode’s specified use. So the only allowed option is reverse polarity.

Polarity direction in SMAW affects how heat is distributed, arc stability, and how the shielding and slag behave. For this F3 electrode, the coating and chemistry are designed to work with the electrode positive (reverse polarity). This setup provides the intended arc characteristics and penetration, along with proper slag formation and deposition. Using AC or the opposite direct polarity would destabilize the arc and degrade weld quality, and would not meet the electrode’s specified use. So the only allowed option is reverse polarity.