Structural Welding Code – Steel (D1.1) City Certification Practice Test

The choice of ER70S-6 as the correct answer is based on its designation as a general-purpose electrode commonly used in various welding applications. This electrode is recognized for its versatility and suitability for welding mild steel and low alloy steel in a range of positions.

The "ER" in the designation stands for "electrode rod," indicating that it can be used for gas metal arc welding (GMAW) and flux-cored arc welding (FCAW). The "70" specifies the minimum tensile strength of the weld metal in thousands of pounds per square inch (psi), which is 70,000 psi. The "S" indicates it is a solid wire, and the "-6" signifies that it contains a higher level of deoxidizers, making it suitable for welding in conditions where surface contaminants may be present.

General-purpose electrodes are designed to provide good weld quality under a variety of circumstances, and ER70S-6 fits this requirement well because it provides excellent arc stability, good wetting characteristics, and a smooth bead appearance.

In contrast, the other options pertain to electrodes intended for more specialized applications or materials. For example, E70C-X is a copper-coated electrode for specific types of welding, E100T