Magmate 180P, Руководство по эксплуатации

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2.1 Introduction to Metal Inert
Gas (MIG)
MIG welding embraces a group of arc welding
processes in which a continuous electrode (the
wire) is fed by powered feed rolls (wire feeder)
into the weld pool. An electric arc is created
between the tip of the wire and the weld pool.
The wire is progressively melted at the same
speed at which it is being fed and forms part of
the weld pool. Both the arc and the weld pool
are protected from atmospheric contamination
by a shield of inert (non-reactive) gas, which is
delivered through a nozzle that is concentric
with the welding wire guide tube.
Operation
MIG welding is usually carried out with a
handheld gun as a semi-automatic process.
The MIG process can be suited to a variety
of job requirements by choosing the correct
shielding gas, electrode (wire) size and welding
parameters. Welding parameters include the
voltage, travel speed, arc (stick-out) length and
wire feed rate. The arc voltage and wire feed
rate will determine the filler metal transfer
method.
This application combines the advantages of
continuity, speed, comparative freedom from
distortion and the reliability of automatic
welding with the versatility and control of
manual welding. The process is also suitable for
mechanised set-ups, and its use in this respect
is increasing.
MIG welding can be carried out using solid
wire, flux cored, or a copper-coated solid wire
electrode. The shielding gas or gas mixture may
consist of the following:
Argon
■
Carbon dioxide
■
Argon and carbon dioxide mixtures
■
Argon mixtures with oxygen or helium
■
mixtures
Each gas or gas mixture has specific advantages
and limitations. Other forms of MIG welding
include using a flux-cored continuous electrode
and carbon dioxide shielding gas, or using self-
shielding flux-cored wire, requiring no shielding.
2.2 Introduction to Flux Cored
Arc Welding (FCAW)
How it Works
Flux-cored arc welding (FCAW) uses the heat
generated by a DC electric arc to fuse the
metal in the joint area, the arc being struck
between a continuously fed consumable filler
wire and the workpiece, melting both the
filler wire and the workpiece in the immediate
vicinity. The entire arc area is covered by a
shielding gas, which protects the molten weld
pool from the atmosphere.
FCAW is a variant of the MIG process and
while there are many common features
between the two processes, there are also
several fundamental differences.
2.0 MIG Operating Manual
1
2
3
4
5
6
7
8
9
10
1 Gun trigger 6 Shroud
2 Welding wire 7 Gas diffuser
3
Weld
8
Contact tip
4 Weld pool 9 Shielding
5
Gun
10
Droplets