Types of Flux-Cored Wires
Flux-cored wires are primarily categorized by their shielding method.
1. Gas-Shielded Flux-Cored (FCAW-G or "Dual-Shield")
Shielding: Requires an external shielding gas cylinder (typically a mix of Argon and CO2, or 100% CO2).
How to Identify: The wire designation will often start with "E" (for electrode) and include a "T-1" (e.g., E71T-1), which indicates it's for use with CO2 gas.
Pros:
Excellent weld quality with very low levels of porosity.
High deposition rates (more metal laid down per hour) compared to many other processes.
Good arc stability and a smooth bead appearance.
Less smoke than self-shielded wires.
Cons:
Requires gas equipment (cylinder, regulator, hose), making it less portable.
Not suitable for windy conditions, as the breeze can blow the shielding gas away.
2. Self-Shielded Flux-Cored (FCAW-S)
Shielding: Creates its own shielding gas from the flux core, requiring no external gas cylinder.
How to Identify: The wire designation will often include a "T-5" or "T-11" (e.g., E71T-11, E71T-5).
Pros:
Extremely portable and ideal for outdoor work (construction, field repairs).
Highly tolerant of wind and drafts.
Deep penetration, good for thick materials and poor fit-ups.
Cons:
Produces more smoke and spatter than gas-shielded wires.
The slag can be more tenacious and require more effort to remove.
The weld bead appearance is often not as clean as with gas-shielded FCAW.
