What causes excessive root reinforcement?

• A. Excessive heat, temperature, and filler metal during welding. Should not exceed 1/16 of an inch
• B. Insufficient heat and filler metal
• C. Too slow travel speed
• D. Low shielding gas

Answer: (A)

Root reinforcement is how high the weld bead sits above the joint at the root. Excessive reinforcement happens when you run too much heat into the joint and deposit too much filler metal in the root pass. Pushing in more heat melts more of the base metal and lets more filler flow into the root, building a bead that protrudes above the surface. There’s usually a practical limit (often around 1/16 inch); going beyond that means the root is overly reinforced. Controlling heat input and the amount of filler used keeps the root bead within spec. While very slow travel speed or other issues can affect the bead in different ways, the direct cause of excessive root reinforcement is excessive heat input combined with too much filler at the root.