Does the Shielded Metal Arc Welding (SMAW) process use constant current or constant voltage?

The Shielded Metal Arc Welding (SMAW) process utilizes a constant current power source. This is essential because the SMAW process is designed to maintain a relatively stable arc length, which is crucial for producing high-quality welds. In this process, the current remains constant, allowing the welder to adjust the arc length by moving the electrode closer to or farther away from the workpiece. As the electrode melts and generates slag, it helps protect the weld pool from atmospheric contamination, which is particularly important for maintaining weld integrity.

Constant voltage, conversely, is typically associated with processes such as GMAW (Gas Metal Arc Welding) where the voltage is maintained constant to facilitate smoother and more steady feeding of the filler material. The characteristics and requirements of SMAW necessitate the use of constant current to achieve the desired control over the weld puddle and penetration depth.

Understanding the distinctions between these power modes is important for welders, as the choice of current type affects the welding technique and the quality of the final weld.