WIA MC105-0, Руководство оператора

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Weldmatic 200i AC/DC
Model No MC105, Iss A 02/16
15
7 Basic Welding Information
Stick Welding (MMAW)
Connection for Stick Welding
It is important to select the electrode polarity
in accordance with the manufacturers
recommendations for that electrode. Most
common electrodes, including cellulose
types, are operated with the electrode at
positive polarity, as illustrated in Figure 6.
Stick Welding
Be certain that you are wearing suitable
protective clothing, gloves etc and that
you are working in a non-hazardous area.
If necessary, refer again to
Section 1 - Safe
Practices in this manual.
Connect the work clamp to the work
piece. Place the desired electrode in the
electrode holder.
Turn on the power switch located on the rear
panel. Wait approximately 5 seconds as the
unit goes through its initiation sequence.
Use the Weld Mode Selection button to
select Stick Mode.
Select an appropriate welding current for
the electrode diameter by setting the knob
on the machine front panel. WIA AUSTARC
electrodes will give the best results.
Work
Clamp Electrode
To strike the arc, drag the end of the
electrode along the work piece as if striking
a match. As the arc initiates, lift the electrode
slightly away, aiming to establish an arc
length of approximately 3mm.
As the electrode end is consumed, feed the
electrode into the arc in order to maintain
arc length. As a general rule, the arc should
be held as short as possible while still giving
stable burn off and good weld appearance.
An arc which is too long causes an unwieldy
flow of metal with a rough weld appearance
and reduced penetration. An arc too short
leads to a narrow weld deposit and “stuttery”
arc characteristics, and the electrode is liable
to freeze onto the work piece.
As the solidified weld deposit forms, move
the end of the electrode slowly along
the weld path, aiming to maintain a pool
of molten weld metal behind the arc.
Decreasing this rate of travel will result in a
wider weld deposit, and similarly increasing it
will narrow the weld deposit.
Always fill the crater which tends to form
at the end of a weld deposit, by pausing
momentarily before withdrawing the electrode
to break the arc. Unfilled craters are a point
of weakness, and can lead to weld cracking.
Current Range for General Purpose
Electrodes
Diameter (mm) Current (Amps)
2.0 40 -60
2.5 60 - 85
3.2 90 - 130
4.0 130 - 180
Fig 6 Connections for Stick Welding (MMAW)