Lincoln Tiny Twinarc Submerged Arc Welding Process

What is tiny twin arc welding?

Tiny Twinarc® is an submerged arc welding process that uses two small diameter electrodes at high wire feed speeds. Tiny Twinarc offers substantial welding economies when used to replace a conventional single electrod for many applications. These economies result from faster travel speeds and higher usuable deposit rates. The two wires in close proximity result in an elongated puddle that improves follow characteristics and enables faster travel speeds while mainteaining the proper weld bead shape. The equipment consists of a power source, an automatic welding head (and controls) with dual drive rolls and guides and a common contact nozzle.


The process offers these advantages over single arc:

  1. High deposition rates – increase of 40% or more are common.
  2. Faster travel speeds – 25% or more on light gauge material and 50 to 70% on heavier material.
  3. Lower heat input and 5 to 50% less distortion. Tiny Twinarc results in low heat input per pound of metal deposited. This aids in controlling distortion and becomes especially important when welding high impact strength steels where the HAZ impacts deteriorate with increased heat input.
  4. Lower power consumption per pound of weld metal.

Tiny Twinarc is a fast, simple welding process that result in low cost fabrication with equal or better weld quality.


The Tiny Twinarc process has application in the manufacture of earth movers, excavators, cement mixers, railcars, code tanks and pressure vessels, thin-walled shells and many other welded products made of material ranging in thickness from 14 gauge (1.9mm) to heavy plate. This system is versatile and is readily usable on:

  1. Light gauge weldments.
  2. Heavy weldments.
  3. For larger circumferential welds where high deposition rates are usable.
  4. Flat fillets, horizontal fillets and lap welds.
  5. Butt welds, including those made in the 3 o’clock position.
  6. Hardfacing application.


Higher Current with the single arc process, rasing the current to increase the deposition rate may result in poor bead shape, undercutting and/or excessive penetration. The Tiny Twinarc process makes the use of higher currents practical.


Resistance heating Another factor contribulting to Tiny Twinarc’s higher deposition rate is the high current density resistance heating effect on the smaller diameter wires.



In conventional single arc operation, it is possible to increase the travel speed by simply increasing the welding current. However, bead shape, bead appearance, undercutting, or burn-through impose a limitation on travel speed. With Tiny Twinarc, the higher usable deposition rate results in arc speed increases, while still maintaining the desirable bead shape, bead placement, penetration and other desirable welding characteristics.


In the welding of horizontal fillets, Tiny Twinarc can increase travel speeds up to 68% for 1/8 inch through 5//16 inch (3.2 through 7.9mm) fillets.



Tiny Twinarc offers about a 50% increase in welding speed over single electrode in the welding of flat fillets.


Small lap welds made with Tiny Twinarc result in welding speed increases of 43 to 70% over single arc.


Tiny Twinarc can be used for prepared groove butt welds on code vessels and heavy-walled tanks. Butt welds can be made economically in the flat and 3 o’clock position. Increased speeds of 30% or more are practical.