SAW · Carbon steel

EM12K

The most widely used submerged arc wire, whose medium manganese and silicon killed chemistry make it forgiving on plate that is not perfectly clean.

What the designation means

E
Electrode, the bare wire that carries the welding current under the flux blanket.
M
Medium manganese content, sitting between the low and high manganese classes of submerged arc wire.
12
The nominal carbon content expressed in hundredths of a percent, so roughly 0.12 percent carbon.
K
Produced from a silicon killed steel heat, which raises the silicon level and improves wetting and tolerance of surface scale.

At a glance

ProcessSAW
FamilyCarbon steel
PositionsFlat groove welds and horizontal fillets only
PolarityDCEP for most single wire work, with DCEN or AC used to raise deposition or in multi-wire setups
ShieldingNone; a granular submerged arc flux blanket shields the arc, and the flux and wire are classified together as a pair
Minimum tensile strength

Typical uses

  • Long seam and girth welds on tanks, vessels, and pipe
  • Structural beam and girder fabrication on automated equipment
  • Heavy plate groove welds where a single pass covers a large cross section

How it runs

  • Silicon from the killed steel practice improves wetting and tolerance of light scale
  • Deposit strength and toughness depend on the flux paired with the wire, not on the wire alone
  • Very high deposition rate with the arc completely buried under flux
  • Slag lifts as a hard shell once the bead has contracted

Storage and handling

Store coils dry and covered; the wire itself is not moisture sensitive, but the flux it runs with must be kept in a heated hopper and rebaked if it gets damp.

Compare with