WIA CP144-1, Руководство оператора

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Weldmatic 350 & 500 | Operator Manual | Model No CP144-2/CP145-2
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TIG Welding (GTAW)
Connection for TIG Welding
For TIG welding, the torch is connected to
the negative terminal. Welding grade Argon
is the shielding gas most commonly used
for DC GTAW welding. The machine does
not have an internal gas valve. The gas is
connected directly to the torch.
Before first use of the welding torch, allow
gas to purge the torch and hoses for
1 minutes at approximately 10 litres/min. For
welding purposes, the gas flow rate should
be set in the range 2-5 litres/min.
Tungsten electrodes for DC GTAW should
be 1-2% Thoriated. This type will provide
the best arc initiation, arc stability and tip
shape retention characteristics. Thoriated
electrodes can be recognised by a red
coded end. The tungsten electrode
is ground to a point, with the grinding
marks pointing towards the tip. For
welding currents less than 20 amps, the
included angle of the point should be 30
o
,
for currents greater than 20 amps, the
recommended angle is 60
o
. When set in the
torch, the tungsten should protrude 6 mm
from the ceramic gas nozzle.
TIG Welding Operation
Connect the Work Clamp to the work piece.
Turn on the power switch located on the rear
panel. Wait approximately 5 seconds as the
unit goes through its initiation sequence.
Press the Weld Process button until the
TIG Process light is on. The Weldmatic
keeps the last process used in memory, so
this step is only necessary when using a
different process to that used last.
Select an appropriate welding current for
the job by setting the knob on the machine
front panel.
Use of a copper striking plate can be used
to avoid electrode contamination. The
electrode can also be contaminated by
contact with the filler rod. A contaminated
electrode produces an unstable arc. If this
occurs regrind the electrode tip.
When in TIG the output is turned on and the
LIFT-ARC voltage is present at the electrode.