12
Maintenance
Maintenance
Switch off the welding machine before check-up or
repair of the welding hose.
Gas nozzle, insulator, electrode clamp and electrode
holder should be dismounted regularly and checked
for defects.
The gas nozzle must be concentric and free from
impurities.
Welding cables must not touch warm workpieces.
Exchange cables with defective insulation.
If the torch is not used for more than 15 minutes, the
shielding gas in the hose must be renewed prior to
reignition. Prior to welding, make sure that there is
sufficient flow of gas and cooling water.
Tungsten electrode
Ignition and welding properties depend on the
quality of the electrode so check regularly the surface
and shape of the tungsten electrode.
Tungsten: grinding
Use a tungsten grinder for grinding the tungsten
electrode. Important: always grind the electrode
lengthwise.
Correct grinding: a focused arc with a narrow heat zone
Poor grinding: a non-focused arc with a wide heat zone
DC welding
Grind the electrode so that its point is twice as long
as its diameter.
Correct pointing
angle of tungsten
electrode
D: Electrode diameter, Ø
S: Pointing angle
L: Length of point
L: = 2 x D
Example: electrode ø 3.2 = 2 x 3.2 = 6.4 mm
AC welding
Keeping the tungsten electrode point sharp during
AC welding is not possible owing to the thermal
impact on the electrode. A slightly bevelled edge of
the electrode will suffice.
Grinding a tungsten
electrode for AC welding
D
S
L
15°
15°
