When would straight polarity be used with SAW?

When would straight polarity be used with SAW?

• A. When shallower penetration is required
• B. When deeper penetration is required
• C. When welding at high speed
• D. When welding thick steel

Answer: (A)

Straight polarity means the electrode is negative, and in SAW this tends to put more heat into the electrode and less into the workpiece. That reduced heat input into the base metal results in shallower penetration and a flatter, wider bead. You’d choose straight polarity when you need to limit penetration—such as on thin sections or when you want to avoid burn-through or excessive weld depth. If deeper penetration is required, you’d switch to the opposite polarity (reverse polarity), which drives more heat into the workpiece and increases penetration.

Straight polarity means the electrode is negative, and in SAW this tends to put more heat into the electrode and less into the workpiece. That reduced heat input into the base metal results in shallower penetration and a flatter, wider bead. You’d choose straight polarity when you need to limit penetration—such as on thin sections or when you want to avoid burn-through or excessive weld depth. If deeper penetration is required, you’d switch to the opposite polarity (reverse polarity), which drives more heat into the workpiece and increases penetration.