AWS Certified Welding Inspector — FundamentalsInspector Duties and ResponsibilitiesMedium
During a multi-pass groove weld inspection, a CWI observes significant slag inclusions on the surface of a completed weld pass before the next pass is deposited. The WPS does not explicitly detail slag removal procedures between passes, but the governing code requires a clean surface before subsequent passes. What action should the CWI take?
- ADocument the observation as a minor non-conformance and allow welding to continue, monitoring for further issues.
- BInstruct the welder to thoroughly remove all slag and visually inspect the surface before allowing the next pass.
- CIssue a stop-work order immediately and require a re-qualification of the welder due to poor workmanship.
- DAllow the welder to proceed, as the WPS does not specify slag removal, and the next pass will likely melt and absorb the slag.
Show answer & explanationAnswer & explanation
Correct answer: B. Instruct the welder to thoroughly remove all slag and visually inspect the surface before allowing the next pass.
Even if the WPS doesn't explicitly detail slag removal, the governing code's requirement for a clean surface between passes takes precedence. Slag inclusions can lead to lack of fusion and other critical defects in the final weld. The CWI must ensure this is addressed immediately.
Why the other options are wrong
- A. Allowing welding to continue with significant slag is a failure of during-welding inspection duties.
- C. While serious, it doesn't immediately warrant re-qualification; correction of the current issue is the first step.
- D. Slag will not necessarily be absorbed and can cause severe defects.
Interpass Cleaning
The process of removing slag, spatter, and other contaminants from the surface of a weld pass before depositing subsequent passes, crucial for preventing defects.
- Ensures proper fusion between weld passes.
- Prevents slag inclusions and porosity.
- Often a code requirement, even if not detailed in WPS.
Memory trick: Clean Passes Ensure Strong Welds.