Excessive current in FCAW can cause which problem?

Excessive current in FCAW can cause which problem?

• A. Convex beads with poor appearance and burn back into the contact tip
• B. Perfect beads
• C. No effect on weld
• D. Reduced penetration

Answer: (A)

Excess current in FCAW increases heat input, causing the weld pool to melt and advance too quickly. That extra heat tends to push the bead outward, producing a convex, poorly shaped bead with a rough appearance. At the same time, the intense heat can cause the electrode near the contact tip to melt back into the tip, a condition known as burn-back, which can foul the contact tip and disrupt the welding process. This combination—a overly convex bead with a burn-back issue—is a classic sign of too much current. The other outcomes don’t fit because perfect beads require appropriate current control; no effect on the weld would ignore the obvious impact of excessive heat; and reduced penetration is typically associated with too little current, not too much.

Excess current in FCAW increases heat input, causing the weld pool to melt and advance too quickly. That extra heat tends to push the bead outward, producing a convex, poorly shaped bead with a rough appearance. At the same time, the intense heat can cause the electrode near the contact tip to melt back into the tip, a condition known as burn-back, which can foul the contact tip and disrupt the welding process. This combination—a overly convex bead with a burn-back issue—is a classic sign of too much current.

The other outcomes don’t fit because perfect beads require appropriate current control; no effect on the weld would ignore the obvious impact of excessive heat; and reduced penetration is typically associated with too little current, not too much.