Additional Information On Submerged Welding; Welding Current; Welding Voltage - NURIS TRACTOR User Manual

ADDITIONAL INFORMATION ON SUBMERGED WELDING

In order for the operator to weld well, she must have knowledge of the necessary welding parameters
and the effects of these parameters on the weld.
Below is a list of information that we believe will be useful as a starting point for welding.

1. Welding current,

2. Welding voltage,

3. Feed rate,
4. Electrode size,
5. Electrode extension,
6. The width and depth of the welding powder layer.
WELDING CURRENT
The welding current is the most influential variable controlling the melting rate of the electrode and
therefore the filling rate, the depth of penetration and the melting base metal.
If the current is too high according to the movement speed, the melting depth and penetration amount
will be high. The resulting weld can completely melt the bonded metals. High current can also lead to
wastage of electrodes in the form of overfilling. This excessive weld also increases weld shrinkage and
causes greater distortion.
If the current is too low, it may cause insufficient penetration or incomplete melting.
There are three rules below regarding welding current:
1. Increasing the current increases penetration and melting rate.
2. Excessive current results in a piercing arc and undercut or a high and narrow seam.
3. A welding current that is too low will cause an unstable arc.
WELDING VOLTAGE
The welding voltage setting specifies the arc length between the electrode and the molten metal.
Increasing the voltage increases the arc length. If the voltage is reduced, the arc length will decrease.
The voltage has little effect on the electrode melting rate. This is determined by the welding current.
Voltage primarily determines the seam cross-section and external appearance.
Increasing the welding voltage with constant current and feedrate:
1. Creates a flatter and wider seam.
2. Increases welding powder consumption.
3. Reduces pores on steel caused by rust or slag.
4. It helps in excessive root opening and bridge formation when the compatibility is bad.
Extremely high voltage:
1. Forms a wide crack-prone weld seam.
2. Makes slag removal difficult in angled welds.
3. It can form a concave-shaped weld that may be subject to cracking.
4. Increases the lower cutting edges of straight welds.
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12/2021 Rev. 1.0