Red Seal Metal Fabricator (Fitter) Practice Exam

What is a common cause of distortion during the welding process?

1. Using a thicker filler material

2. Rapid temperature changes

3. Increased welding speed

4. Excessive pre-heating

The correct answer is: Rapid temperature changes

Distortion during the welding process is primarily caused by rapid temperature changes. When metal is heated during welding, it expands, and when it cools, it contracts. If these temperature changes happen quickly or unevenly, the resultant stresses can lead to warping or distortion of the welded components. This is particularly critical in cases where there are large temperature gradients in the material being welded, such as at the edges or in areas where heat is applied intermittently. In contrast, using a thicker filler material might not necessarily cause distortion; it could be a choice based on the requirements of the joint and may even improve the integrity of the weld. Increased welding speed can lead to quick cooling but is more likely to affect the bead characteristics than to directly cause distortion under typical circumstances. Excessive pre-heating, while potentially problematic, is generally used to avoid distortion by managing thermal effects during the welding process.