Jasic MIG SERIES - MIG Process Description; Typical Welding Ranges

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GUIDE TO MIG/MAG WELDING
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
MIG process descripon
The MIG process was rst patented for the welding of
aluminium in 1949 in the USA.
The process uses the heat that is generated by an electric
arc formed between a bare consumable wire electrode and
the work piece.
This arc is shielded by a gas to prevent oxidaon of the weld.
In the MIG process an inert shielding gas is used to protect
the electrode and weld pool from contaminaon and
enhance the arc. Originally this gas was helium.
In the early 1950’s the process became popular in the UK
for welding aluminium using argon as the shielding gas.
Development in the use of dierent gases resulted in the
MAG process. This is where other gases were used, for
example, carbon dioxide and somemes users refer to the process as CO2 welding. Gases such as oxygen
and carbon dioxide were added and are acve constuents to the inert gas to improve the welding
performance. Although the MAG process is in common use today it is sll referred to as MIG welding
although technically this is not correct. The process began to prove itself as an alternave to sck
electrode (MMA) and TIG (GTAW) oering high producvity and deposion rates. The process also helps
reduce any weld defects from the increased stop/starts used in MMA. However, the welder must have a
good knowledge of the system set up to achieve sasfactory welds.
The electrode MIG gun is normally +VE and the work return is normally –VE. However, certain
consumable wires somemes require what is called reverse polarity i.e. Electrode –VE or work +VE.
Typical of these types of wire are cored wires used in hard facing or high deposion and gasless
applicaons.
Typical welding ranges
Wire Diameter DIP Transfer Spray Transfer
(mm)
Current (A) Voltage (V) Current (A) Voltage (V)
0.6 30 ~ 80 15 ~ 18 n/a n/a
0.8 45 ~ 180 16 ~ 21 150 ~ 250 25 ~ 33
1.0 70 ~ 180 17 ~ 22 230 ~ 300 26 ~ 35
1.2 60 ~ 200 17 ~ 22 250 ~ 400 27 ~ 35
1.6 100 ~ 280 18 ~ 22 250 ~ 500 30 ~ 40