After cleaning, what should you avoid doing to the pipe?

• A. Grabbing the pipe with tongs
• B. Touching the pipe with your hand
• C. Welding immediately
• D. Re-cleaning with solvent

Answer: (B)

Touching the pipe with your bare hand should be avoided after cleaning. Bare skin carries oils, sweat, and moisture that can transfer onto the freshly cleaned surface, recontaminating it and compromising weld quality. In GTAW, a clean, uncontaminated surface is crucial for good fusion, proper wetting, and avoiding defects like porosity or inclusions. Handle the pipe with clean gloves or use tongs so you don’t reintroduce contaminants before welding. Welding immediately is not inherently wrong after cleaning, but only if the surface remains uncontaminated; re-cleaning with solvent isn’t typically required if handling keeps the surface clean.