Mig/Mag Welding; Shield Gas; Description - Praxair MIG SELECT-300H/4R Guide De L'utilisateur

2 –Mig/Mag Welding
This semi-automatic arc welding process can use argon and mixed argon inert shield gas (MIG process - Metal Inert Gas) or
CO2 active shield gas (MAG process - Metal Active Gas) to ensure a deoxidised atmosphere on welding zone. For some special
applications this machine is also suitable for fluxed cored wire arc welding (FCAW) with or without shielding gas.
WELDING METAL
Carbon steel
Stainless steel
Al Si (Aluminium/Silicon)
Al Mg (Aluminium/Magnesium)
CuSi (Copper/Silicon)
When compared with CO2, the use of mixed Ar+CO2 creates more stability to the welding arc with low spatters and a better
finishing of the welding seam. There are also other gas mixtures like Argon/Helium to increase penetration or Argon/Oxygen and
others. For specialized jobs, a consult to gas suppliers is advised.
CO2 seam
(Inductance plug nr. 1)
2 inductance plugs MIG 300

2.1 - Description

The complete set of these machines consists of the power source, the connecting cable and the wire feeder with coil holder and
4 rolls wire feeding motor.
Front panel
MIG SELECT 300H/4R / 350H/4R / 400H/4R / 500H/4R / 650H/4R
100% CO2 (Carbon dioxide)
80% Ar (Argon) + 20% CO2
85% Ar +15% CO2
98% Ar + 2% CO2
95% Ar + 5% CO2
100% Ar
100% Ar
85% Ar + 15% He (Helium)
Argon/CO2 seam
(Penetration – inductance plug nr.2)
Fig.1 – Inductance plugs
3 inductance plugs MIG 350 / MIG 400 / MIG 450 / MIG 500 /
MIG 650
Fig.2 – Front panel

SHIELD GAS

Argon/CO2 seam
(Filling – inductance plug nr. 3)
5