Unimig VIPER 182 Mk II, Operating Manual

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Wire types and sizes
Use the correct wire type for the base metal being welded. Use stainless steel wire for stainless steel,
aluminium wires for aluminium and steel wires for steel.
Use a smaller diameter wire for thin base metals. For thicker materials use a larger wire diameter and larger
machine, check the recommended welding capability of your machine.
As a guide, refer to the “Welding Wire Thickness Chart” below.
Material
Type
Wire Type Wire Size
Drive
Roller
Polarity
Shielding
Gas
Gas Flow Rate Material Thickness 1mm 2mm 3mm 4mm 6mm 8mm
Steel
ER70S-6 0.8mm V Groove DCEP+ ArCO
2
8-12L/min
Voltage (V) 15 18 20 21 23 23
Wire Speed (m/min) 5 7.5 8.5 9 12 13
ER70S-6 0.9mm V Groove DCEP+ ArCO
2
8-12L/min
Voltage (V) 18 18.5 19 22 23
Wire Speed (m/min) 6 7 7.5 11 13
E71T-11 0.8mm
F Groove
(Knurled)
DCEN-
Voltage (V) 14 17 21 22 23
Wire Speed (m/min) 3.5 5.5 8.5 9 11
E71T-11 0.9mm
F Groove
(Knurled)
DCEN-
Voltage (V) 15 18 19 20 22 23
Wire Speed (m/min) 4 5 5.5 6 8 9
Stainless
Steel
316LSi 0.8mm V Groove DCEP+ ArCO
2
8-12L/min
Voltage (V) 12 13 14.5 16 17 19
Wire Speed (m/min) 7 8 9 10 11 15
316LSi 0.9mm V Groove DCEP+ ArCO
2
8-12L/min
Voltage (V) 13 14.5 16 18 20
Wire Speed (m/min) 7 8 9 10 14
Aluminium 5356 1.0mm U Groove DCEP+ Ar 8-12L/min
Voltage (V) 11 12 13 17 18
Wire Speed (m/min) 9 10 11 14 16
Argon-CO₂ CO₂
Gas selection
The purpose of the gas in the MIG process is to protect/shield the wire, the arc and the molten weld metal
from the atmosphere. Most metals when heated to a molten state will react with the air in the atmosphere,
without the protection of the shielding gas the weld produced would contain defects like porosity, lack of
fusion and slag inclusions. Additionally, some of the gas becomes ionised (electrically charged) and helps the
current flow smoothly.
• The correct gas flow is also critical in protecting the welding zone from the atmosphere.
• Too low flow will give inadequate coverage and result in weld defects and unstable arc conditions.
• Too high flow can cause air to be drawn into the gas column and contaminate the weld zone.
Use the correct shielding gas. Co2 is suitable for steel and offers good penetration characteristics; the
weld profile is narrower and slightly more raised than the weld profile obtained from Argon Co2 mixed gas.
Argon Co2 mix gas offers better weldability for thin metals and has a wider range of setting tolerance on the
machine. Argon 80% Co2 20% is a good all-round mix suitable for most applications.
MIG WELDING GUIDE
30