In repairs, what approach should be taken regarding heat input and inspection?

• A. Increase heat input and skip inspection.
• B. Minimize heat input; verify filler metal compatibility; inspect for new defects.
• C. Use new process; do not inspect.
• D. Increase heat input but inspect thoroughly.

Answer: (B)

In repairs, the focus is on preserving the material and the integrity of the joint by keeping heat input as low as practical. Excess heat can enlarge the heat-affected zone, introduce more residual stress, and increase distortion or cracking near the repair. By minimizing heat input, you reduce those risks and help the repaired area behave more like the original metal.

Along with controlling heat, it’s crucial to ensure the filler metal you use is compatible with the base metal and the service environment. This means matching the filler’s chemistry and mechanical properties so the weld joint has the expected strength, hardness, and corrosion resistance, and won’t become a weak point or a potential site for cracking.

After the repair, inspect the weld for any new defects that may have formed during welding—porosity, cracks, lack of fusion, or misalignment. This verification step confirms the repair is sound and safe to service.