Under what condition may arc shields (Ferrules) remain in place after welding?

When considering the use of arc shields or ferrules after the welding process, it's essential to refer to the guidelines stated in the AWS D1.1 Structural Welding Code. Arc shields are typically designed to protect the weld area during the welding process, and while they can serve a purpose during welding, they often need to be removed afterward to ensure proper inspection and testing of the weld quality.

The correct answer indicates that none of the scenarios presented allow for the ferrules to remain in place after welding. This is rooted in the principle that any obstructions—like arc shields—can hinder the visual inspection of the weld and could potentially conceal defects. Therefore, after the welding is completed, for the integrity of the inspection process and to maintain quality assurance standards, these ferrules must be removed.

By following this guideline, inspectors can thoroughly assess the welds for quality, ensuring compliance with the code and ensuring overall structural integrity.