What does the "8" in the designation E71T-8 indicate?

The "8" in the designation E71T-8 signifies the type of shielding gas used and the current polarity suitable for the electrode. In this context, it denotes that the electrode is designed for use with a specific shielding gas, usually CO2 or a mixture of gases, and that it generally operates with DC negative polarity. This indication is critical for ensuring proper welding characteristics, such as arc stability and penetration, which depend significantly on the polarity and gas mixture utilized.

The number also suggests that electrodes with this designation are intended for all-position welding applications and can effectively handle various materials and joint configurations. The right shielding gas, along with the designated polarity, contributes to the overall performance and quality of the weld, making it essential for welders to understand this designation clearly.