Magmate 180P, Руководство по эксплуатации

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If the cast is too large the wire will move in an
upward direction from the tip when welding
and if too small the wire will dip down from the
tip. The result of this is excessive tip wear and
increased wear in the liners.
If the helix is too large the wire will leave the
tip with a corkscrew effect.
Selection of the Correct Power Source
Power sources for MIG welding is selected on a
number of different criteria, including:
Maximum output of the machine 1
Duty cycle 2
Output control (voltage selection, wire feed
3
speed control)
Portability
4
The following table gives an indication of the
operating amperage for different size wires.
Wire Size Amperage Range (A)
0.8 mm 60–180
0.9 mm 70–250
1.0 mm 90–280
1.2 mm 120–340
Selection of the Correct Polarity on the
Power Source
Many power sources are fitted with an optional
reverse polarity dinse connector.
To achieve the optimum welding it is important
to adhere to the consumable manufacturer's
instruction to select the polarity.
As a general rule all solid and metal cored wires
are welded on electrode positive. (Work return
lead fitted to the negative connector.)
Some grades of self shielded flux cored wires
(i.e. E71T-11, E71T-GS etc) needs to be welded
on electrode negative. (Work return lead fitted
to the positive connector.)
Selection of the Correct Shielding Gas
The selection of the shielding gas has a direct
influence on the appearance and quality of the
weldbead.
The thickness of the material to be welded will
determine the type of shielding gas that has to
be selected. As a general rule the thicker the
material (C-Mn and Alloy steels) are the higher
the percentage of CO
2
in the shielding gas
mixture.
Different grades of shielding are required for
materials such as stainless steel, aluminium
and copper.
The following table gives an indication of the
most common shielding gases used for Carbon
Manganese and alloy steel.
Material thickness Recommended
shielding gas
1–8 mm Argoshield Light
5–12 mm Argoshield Universal
>12 mm Argoshield Heavy
More detailed selection charts, including
recommendations for welding parameters
(voltage, amperage, electrical stickout,
travelspeed and gasflow rate) can be found in
the following pages.