Metal Inert Gas or MIG weld process have in common the electrode used as the filler
wire which is continuously fed and heating the job with an arc is established on
the work, total or partial inert gas used for shielding the produced arc. There is
no flux used for weld, helium, argon, carbon-dioxide or some gas mixture is used
to shield for the arc and molten metal from atmosphere.
There are two types of MIG welds are used, one fully automated and other is semi-automated.
The semi-automated version is used in very largely.
MIG Welding Principle
This welding process is said for semi-automated MIG welding. Check the electrical
supply, water supply and gas flow in before going to ignition started. Then set the
feed of electrode and proper current also. The electrode should be projected about
12-16 mm from the torch tip before going to start arc. The arc length should be maintaining
about 2-4mm and the torch tip should be 10-12mm from the work piece. To produce the
arc the shielding gas and proper current supply is to be on and scratch the electrode
against the job, then moved forward to carry out MIG welding. Always take in mind
that the electrical supply, gas flow and water supply should be on. The torch is
moved along the joint for carrying out the welding process and the torch angle is
about 700with the horizontal.
MIG welding has large used in automobile industry, aircraft parts welding, pressure
vessel manufacturing and many other places.For welding tool steels, carbon, silicon
and low allow steels, stainless steel, aluminium and its alloy, magnesium, nickel
and its alloy, copper and its alloy, titanium and so many metals.
It is used for refrigerator parts manufacturing .
There are many advantages of MIG welding mention bellow:
Joints can produce with deep penetration.
The metals thickness can not be vary with this MIG welding process. Thick and thin
metals are welded very effectively.
This welding process is very suitable for large scale production unit because, it
can be performed much faster than other types of welding process like TIG etc.
Large amount of metal can be deposited on the work piece.
MIG welding process can reduces the welding cost, because it produces neat and clean
metal deposit on the work piece. Spatter free and smooth welding surface is produced,
so it is no need to extra cleaning.