What can happen if the arc length is not properly maintained during GMAW?

Maintaining the correct arc length during Gas Metal Arc Welding (GMAW) is critical for achieving a stable and high-quality weld. If the arc length is not properly maintained, it can lead to instability in the arc. An unstable arc can result in inconsistent heat distribution, leading to poor penetration or excessive spatter. This adversely affects the overall quality of the weld, resulting in defects such as undercuts or insufficient fusion between materials.

The relationship between arc length and heat input is crucial; a longer arc generally means less heat on the workpiece, while a shorter arc can cause excessive heat, potentially burning through the material or producing a poor surface finish. Therefore, improper arc length not only affects the immediate quality of the weld but can also compromise the integrity and strength of the welded joint itself.