Which FCAW wire grade is NOT typically used for self-shielding?

The correct choice is D, E492T-10, because it is not typically used for self-shielding in flux-cored arc welding (FCAW). The E492T designation indicates that the wire is designed for use with an external shielding gas instead of relying on the slag environment created by the flux in the core.

Self-shielded FCAW wires, on the other hand, are designed to perform optimally without additional gas protection, utilizing the flux to provide a protective atmosphere around the weld pool. Wires such as E490T-2, E492T-5, and E491T-7 are formulated for self-shielding processes, making them suitable for applications where portability and convenience are primary concerns, as they eliminate the need for external gas supply.

In contrast, self-shielded wires typically have different compositions and characteristics that allow for effective welding under these conditions, ensuring that they can protect the molten weld from atmospheric contamination without the need for additional shielding gas. This distinction is crucial in selecting the right FCAW wire for specific welding scenarios.