Which welding process cannot be qualified by radiography?

Which welding process cannot be qualified by radiography?

• A. GTAW
• B. GMAW (short circuit mode)
• C. SMAW
• D. SAW

Answer: (B)

Radiography tests look inside the weld to reveal hidden flaws, and they work well when the interior of the weld is relatively uniform and easy to interpret. Gas metal arc welding in short-circuit transfer, however, tends to produce highly irregular root regions with variable penetration and potential porosity or other defects that can be difficult to interpret clearly on a radiograph. The dynamic nature of the short-circuit transfer makes it hard to show consistent, code-acceptable indications of sound fusion and penetration in a way that satisfies procedure-qualification criteria. For that reason, this particular mode of GMAW isn’t qualified by radiography, while other processes like GTAW, SMAW, and SAW generally provide interior weld characteristics that radiographs can reliably assess.

Radiography tests look inside the weld to reveal hidden flaws, and they work well when the interior of the weld is relatively uniform and easy to interpret. Gas metal arc welding in short-circuit transfer, however, tends to produce highly irregular root regions with variable penetration and potential porosity or other defects that can be difficult to interpret clearly on a radiograph. The dynamic nature of the short-circuit transfer makes it hard to show consistent, code-acceptable indications of sound fusion and penetration in a way that satisfies procedure-qualification criteria. For that reason, this particular mode of GMAW isn’t qualified by radiography, while other processes like GTAW, SMAW, and SAW generally provide interior weld characteristics that radiographs can reliably assess.