GMAW · Carbon steel
ER70S-2
The most heavily deoxidised of the common carbon steel wires, which is why it tolerates rust and mill scale and is the standard pick for open root passes.
What the designation means
- ER
- Usable either as an electrode carrying current or as a filler rod fed by hand, which is why the same wire serves both wire feed and torch welding.
- 70
- 70,000 psi minimum tensile strength of the deposited weld metal.
- S
- Solid wire, as opposed to a tubular flux cored product.
- -2
- The chemistry class, a triple deoxidised wire carrying titanium, zirconium, and aluminium on top of the usual silicon and manganese.
At a glance
| Process | GMAW |
|---|---|
| Family | Carbon steel |
| Positions | All positions with short circuit or pulsed transfer; axial spray is limited to flat and horizontal fillets |
| Polarity | DCEP for wire feed welding; DCEN when the same wire is used as a hand fed rod |
| Shielding | 100 percent carbon dioxide or an argon-carbon dioxide blend for wire feed work; welding grade argon when used as a hand fed rod |
| Minimum tensile strength | 70 ksi |
Typical uses
- Open root passes on pipe and heavy plate
- Welding steel that carries light rust or mill scale
- Single-pass work where the deoxidisers protect against porosity
How it runs
- Extra deoxidisers scavenge oxygen, keeping the deposit free of porosity on less than clean steel
- Clean, well wetted root bead with a smooth underside
- Slightly less silicon glass on the bead than the higher silicon wires
- Costs more than the plainer deoxidised wires, so it is usually reserved for roots and dirty material
Storage and handling
Keep spools in the original sealed bag with desiccant and store in a heated area; surface rust on the wire causes feeding trouble and porosity.
Compare with
GMAWER70S-3The middle of the road carbon steel wire, deoxidised enough for clean plate and light scale but leaner than the high silicon wire that dominates general fabrication.GMAWER70S-6The most widely used carbon steel wire feed consumable, with enough silicon and manganese to weld through light rust and scale while wetting out into a flat bead.FCAWE70T-1The downhand version of the rutile flux cored family, trading position capability for a larger, more fluid puddle and higher deposition rate in the flat.