gala gar Smart 140 MMA, Instruction Manual

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Smart 140 MMA battery 16
5.2. WELDING PARAMETERS.
Selection of manual arc welding parameters
SN. Thickness/mm.
Welding rod diameter
/mm.
Welding rod
diameter
/mm.
Welding current /A Remarks.
1. 1.6 25-40
2.
<4
2.0-3.2
2.0 40-65
2.5 50-80 Usually used
3.2 100-130 Usually used
3. 4-12 3.2-4
3.2 100-130 Usually used
4.0 160-210 Usually used
4. >12 >4
4.0 160-210
5.0 200-270
6.0 260-300
We must assure a good heart connection, because a bad contact of the mass will cause this to heat up, the
current passage will be interrupted and the arc will disappear.
It is advisable for this cable to be as short as possible. We will thus reduce the electromagnetic disturbances.
Whenever electric current circulates, a circular magnetic field is generated around the conductor. This magnetic
field is generated from the connection of the negative pole to the positive pole. This phenomenon produces
deviation of the electric arc that is called magnetic blow out.
This phenomenon occurs at the ends of the parts and will appear in applications with direct currents. In welding
with alternating current, this is overridden in each cycle as there is a change in direction of the current.
TO MINIMISE THE EFFECT OF THE MAGNETIC BLOW-OUT:

Welding must be carried out as far away as possible from the mass.

Place tabs at the ends of pieces.

Reduce arc length.

Incline the torch in the opposite direction to the field.

Reduce the current intensity to a minimum, as the magnetic field intensity is directly proportional to
the circulating current.