E71T-8 Seismic-Rated Self-Shielded Flux-Core Wire
E71T-8 Amperage by Diameter
| Diameter | Amperage Range |
|---|---|
| 0.045" (1.2 mm) | 130 - 230A |
| 0.052" (1.4 mm) | 150 - 280A |
| 5/64" (2 mm) | 175 - 350A |
E71T-8 is a self-shielded flux-cored wire classified under AWS A5.20 with T-8 designator indicating a self-shielded wire designed for all-position welding with DCEN polarity. It meets the requirements for use in seismic-demand applications under AWS D1.8 Structural Welding Code - Seismic Supplement. E71T-8 must pass Charpy V-notch impact testing at -20F with a minimum of 20 ft-lbs average. This wire is used for structural steel erection, including moment frames, braced frames, and connections in seismic zones. It requires no external shielding gas, making it practical for field erection where gas coverage is difficult. The self-shielded design tolerates wind better than gas-shielded processes. Typical applications include multi-story steel building erection, bridge structural connections, and industrial structures in seismic regions.
What This Means in Practice
E71T-8 is the structural upgrade to E71T-11. Both are self-shielded (no gas needed), but E71T-8 carries a seismic demand classification meaning it meets the stricter requirements of AWS D1.8 for buildings in earthquake zones. It also has mandatory Charpy impact testing at -20F, making it suitable for cold-climate structural work.
E71T-8 Suitability Scores
How well this electrode matches common applications. Not a quality rating. all AWS-certified electrodes meet their specification.
When to Use E71T-8
Use E71T-8 when the structural code or WPS specifies a self-shielded flux-core wire with seismic demand classification or -20F impact testing.
Required for AWS D1.8 seismic welding.
Preferred for field erection of structural steel in windy conditions where gas-shielded processes are impractical.
E71T-8 Limitations
Produces more fume than gas-shielded wires.
Requires DCEN polarity (most MIG welders default to DCEP, so polarity swap is needed).
More expensive than E71T-11.
Spatter and slag are heavier than gas-shielded alternatives.
Not suitable for thin material.
Designed for structural steel, not general-purpose shop work.
E71T-8 Storage Requirements
Store in dry conditions. Keep wire sealed until use. Self-shielded flux-core wire is less moisture-sensitive than low-hydrogen stick electrodes but should be protected from prolonged humidity exposure.
E71T-8 Technical Specifications
| Property | Value |
|---|---|
| AWS Classification | E71T-8 |
| Process | flux-core-wire () |
| Polarity | DCEN |
| Positions | flat, horizontal, vertical up, overhead |
| Penetration | medium-deep |
| Coating Type | self-shielded flux core |
| Tensile Strength | 70,000 psi |
| Yield Strength | 58,000 psi |
| Elongation | 22% |
| Impact Toughness | 20 ft-lbs at -20°F |
| Base Metals | Structural steel (A36, A572, A992), Bridge steel |
| AWS Specification | A5.20 |
Frequently Asked Questions
What is the difference between E71T-8 and E71T-11?
Both are self-shielded flux-core wires, but E71T-8 is the structural upgrade. E71T-8 carries seismic demand classification for AWS D1.8 and requires Charpy impact testing at -20F. E71T-11 has no mandatory impact testing requirement and is not approved for seismic applications. Use E71T-8 for structural steel erection and code work. Use E71T-11 for general-purpose field welding and repairs.
Can I use E71T-8 on a standard MIG welder?
Yes, but you must switch the polarity to DCEN (electrode negative). Most MIG welders default to DCEP. Self-shielded flux-core wires like E71T-8 run on DCEN. You also need knurled drive rolls to grip the tubular wire without crushing it. No shielding gas is needed, so disconnect or turn off the gas solenoid.
Why is E71T-8 used for building erection?
E71T-8 is self-shielded, so it works in wind without losing gas coverage. Structural steel erection happens outdoors at height where wind is constant. E71T-8 also meets seismic code requirements (AWS D1.8), provides all-position capability for welding beam-to-column connections, and offers high deposition rates for the heavy welds required in moment frames.
External Resources
Manufacturer data sheets and standards for E71T-8.
Data sourced from AWS A5.20/A5.20M, AWS D1.8. Amperage ranges are approximate starting points. adjust based on position, fit-up, and material thickness. Always follow manufacturer recommendations and applicable codes.