AWS A5.20/A5.20M · Flux-Cored
E71T-1 Welding Electrode
E71T-1 is gas-shielded flux-cored wire — the high-deposition, all-position production workhorse for structural steel, combining FCAW speed with a smooth spray-like arc.
- 70 ksi tensile
- Polarity DCEP
- 4 positions
- Medium to deep penetration
- Flux-Cored (FCAW)
What E71T-1 means
| Part | Meaning |
|---|---|
| E | Electrode |
| 7 | 70,000 psi minimum tensile strength |
| 1 | All welding positions |
| T | Tubular (flux-cored) wire |
| -1 | Rutile slag system, gas shielded, DCEP, with 20 ft·lb impact toughness at 0 °F |
E71T-1 specifications
| AWS specification | AWS A5.20/A5.20M |
|---|---|
| Process | Flux-Cored (FCAW) |
| Form | Tubular wire |
| Polarity | DCEP |
| Welding positions | Flat, Horizontal, Vertical, Overhead |
| Tensile strength (min) | 70 ksi (480 MPa) |
| Yield strength (min) | 58 ksi (400 MPa) |
| Elongation (min) | 22% |
| Impact toughness | 20 ft·lb at 0 °F (27 J at -18 °C); -1J and -1M grades extend this to -20 °F |
| Coating / core | Rutile flux core inside a mild steel sheath |
| Penetration | Medium to deep |
| Deposition rate | Very high — roughly twice the rate of a comparable stick electrode |
| Slag | Fast-freezing rutile slag that supports the puddle out of position and peels readily |
| Arc character | Smooth, spray-like, with a fine droplet transfer |
| Shielding gas | 100% CO2 or 75% argon / 25% CO2 |
E71T-1 amperage by diameter
Typical operating ranges. Start near the middle of the range, then adjust by sound and bead profile. Reduce 10–15% for vertical and overhead work.
| Diameter | Amperage range | Typical start |
|---|---|---|
| 0.035 in (0.9 mm) | 90–250 A | 170 A |
| 0.045 in (1.2 mm) | 150–350 A | 250 A |
| 0.052 in (1.4 mm) | 180–400 A | 290 A |
| 1/16 in (1.6 mm) | 200–450 A | 325 A |
Polarity: DCEP. This is the opposite of self-shielded T-11 wire, which runs DCEN — getting the polarity backwards is the most common setup mistake when switching between the two.
Shielding gas for E71T-1
| Gas | Notes |
|---|---|
| 100% CO2 | Deeper penetration, lower gas cost, more spatter. The classic choice for structural work. |
| 75% Ar / 25% CO2 | Smoother arc, less spatter, slightly higher deposition efficiency and better out-of-position control. Higher tensile than the same wire on CO2. |
Flow rate: 35–45 CFH (16–21 L/min). FCAW-G needs more flow than solid-wire MIG, and it cannot be used outdoors without a windscreen.
What E71T-1 is used for
- Structural steel fabrication and erection
- Shipbuilding and barge construction
- Heavy equipment and earthmoving machinery
- Pressure vessel fill and cap passes
- Any indoor production joint where deposition rate drives cost
Base metals
- A36 and A572 structural steel
- A516 pressure vessel plate
- Heavy plate and structural shapes
- Shipbuilding and offshore steels
Characteristics
- Deposition rates far above stick and above solid MIG wire at equal amperage
- The slag system holds the puddle for genuine all-position welding at high current
- Requires external shielding gas — wind over about 5 mph will cause porosity
- Higher fume generation than solid wire; good local exhaust matters
- Slag must be removed completely between passes or inclusions result
Storage and handling
Keep dry. The flux core absorbs moisture through the seam of the wire, and damp wire means porosity and hydrogen cracking.
- Store unopened spools in a dry area at normal shop temperature.
- Once a spool is opened, either use it or return it to a sealed bag with desiccant, or hold it in a heated cabinet at 250–300 °F (120–150 °C).
- A spool left on the machine over a humid weekend will often show porosity in the first several feet — run it off before starting critical work.
- Surface rust on the sheath means the spool should be discarded.
Welding tips
- Use a contact-tip-to-work distance around 3/4 to 1 in — considerably longer than solid-wire MIG.
- Drag the gun with a 5–15 degree drag angle so the slag trails the puddle.
- For 0.045 in wire on plate, about 26–28 V and 300–350 ipm is a solid starting point on CO2.
- Knurled drive rolls with light tension — a tubular wire crushes if you clamp it like solid wire.
- Do not use FCAW-G outdoors without a windscreen; if you need wind tolerance, switch to a self-shielded wire such as E71T-11 or E71T-8.
E71T-1 frequently asked questions
What gas do you use with E71T-1?
100% CO2 or 75% argon / 25% CO2. CO2 penetrates deeper and costs less; the argon mix gives a smoother arc, less spatter and better out-of-position control.
Is E71T-1 DCEP or DCEN?
DCEP, electrode positive. Self-shielded wires such as E71T-11 run DCEN, so the polarity must be changed when switching between the two types.
What is the difference between E71T-1 and E71T-11?
E71T-1 is gas shielded, runs DCEP, and produces tougher, higher-quality welds suitable for code work. E71T-11 is self-shielded, runs DCEN, needs no gas bottle, and tolerates wind — but has lower toughness and is usually thickness limited.
What settings for 0.045 in E71T-1?
Roughly 26–28 V with 300–350 ipm wire feed on CO2, which works out around 250–300 A. Use about 3/4 in contact tip to work distance.
Can E71T-1 be used outdoors?
Not without shelter. It depends on external shielding gas, and wind above about 5 mph blows the gas away and causes porosity. Use a self-shielded flux-cored wire outdoors.
Compare E71T-1 with
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