When ARC welding with DC straight polarity, which pole is the work?

In direct current (DC) arc welding using straight polarity, the positive pole is the one connected to the electrode, while the negative pole is connected to the workpiece. This setup is significant because it affects both the heating characteristics and the depth of penetration of the weld.

When the electrode is the positive terminal, it attracts more electrons from the workpiece (the negative terminal). As the arc forms, a significant amount of heat is generated at the workpiece due to this electron transfer, leading to deeper penetration and a more focused heat source. The selection of straight polarity typically results in better fusion and weld quality for specific types of electrodes and materials.

In comparison, other polarities, such as reverse polarity (where the work is connected to the positive terminal), will have different heating and penetration characteristics. Understanding this relationship is essential in making informed decisions regarding equipment setup and weld quality in various applications.