Following a major repair of a heavy equipment frame, a welder has completed several passes of a large fillet weld. Upon visual inspection, the weld profile appears excessively convex, with the face of the weld bulging outwards significantly, and the weld toe does not blend smoothly into the base metal. What corrective action is generally recommended to address excessive convexity to meet CSA W59 requirements, and why is it important?

Question: Following a major repair of a heavy equipment frame, a welder has completed several passes of a large fillet weld. Upon visual inspection, the weld profile appears excessively convex, with the face of the weld bulging outwards significantly, and the weld toe does not blend smoothly into the base metal. What corrective action is generally recommended to address excessive convexity to meet CSA W59 requirements, and why is it important?

Answer options:

• No action is required as long as the weld is strong. ✅ Grind the excess weld metal to achieve the specified flush or slightly convex profile, as high convexity can concentrate stress at the toes.
• Add more weld metal to further build up the weld, increasing its size and strength.
• Paint over the weld to hide the excessive convexity from view.

Correct answer: Grind the excess weld metal to achieve the specified flush or slightly convex profile, as high convexity can concentrate stress at the toes.

Explanation: Excessive convexity (overfill) is a discontinuity because it can lead to stress concentration at the weld toes, potentially reducing fatigue life. The recommended corrective action under CSA W59 is to grind the excess weld metal to achieve a flush or slightly convex profile, ensuring a smooth transition to the base metal and reducing stress risers. Adding more weld metal would worsen the problem.