Red Seal Metal Fabricator (Fitter) Practice Exam

How can you prevent slag inclusion in a weld?

1. By using lower welding temperatures

2. By cleaning the weld area and using proper techniques

3. By reducing the amount of filler material

4. By increasing the welding speed

The correct answer is: By cleaning the weld area and using proper techniques

Preventing slag inclusion in a weld primarily involves cleaning the weld area and utilizing proper welding techniques. Slag inclusion occurs when non-metallic solid materials, such as oxides and other contaminants, become trapped in the weld metal during the welding process. When the weld area is not adequately cleaned, contaminants can mix with the molten metal, leading to defects within the finished weld. Proper cleaning includes removing any rust, paint, moisture, and other foreign substances from the base metal surface before welding. In addition, employing proper techniques during the welding process—such as maintaining appropriate heat and angle, and using the correct welding parameters—can also help ensure that slag is less likely to become entrapped in the weld. Adhering to these practices supports stronger, more reliable welds, free from inclusions that could compromise the integrity of the weld joint.