Submerged Arc Welding Technical Handbook - Esab

If the welding speed is decreased beyond a
certain point, the penetration will also
decrease. This is because a good portion of
the molten weld pool will be beneath the
welding wire and the pool will cushion the
penetrating force of the arc.
Effect of wire extension on weld profile.
Welding direction
Width and depth of welding flux
If the granular layer is too deep, a rough
weld is likely to result. The gases generated
during welding cannot readily escape, and
the surface of the molten weld metal is
irregularly distorted.
If the granular layer is too shallow, the
welding zone will not be entirely submerged.
Flashing and spattering will be present; the
weld will have a bad appearance, and may
Pulling
(backhand)
Neutral
Pushing
(Forehand)
be porous. An optimum depth of granular
material exists for any set of welding
conditions. This depth can be established
by slowly increasing the granular material
Circumferential welding
until the welding action is submerged and
flashing no longer occurs.
Electrode extension
The distance between the contact tip and
work-piece is normally referred to as electrode
extension or stick-out and is typically between
Small offset
at edges
Desired offset
slight reinforcement
Large offset
at centre and high at
edges
increased with the use of longer extensions
due to resistive heating of the wire. If the stickout
is too long then the wire is preheated and
can tend to wander leading to miss-alignment
also penetration is reduced.
Angle of welding head
The pulling or backhand technique gives
greater penetration and a narrower weld
with a more convex weld bead. There is
increased risk of undercut using this
Weld metal dilution
depends on the joint
preparation.
technique. Conversely pushing or forehand
will give less penetration, a less convex weld
bead and a low risk of undercut.
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