Instruction manual

51
1: Tungsten burning away quickly
Possible Reason Suggested Remedy
Incorrect Gas Check that pure Argon is being used
No gas Check the gas cylinder contains gas and is connected and the torch gas valve is open
Inadequate gas ow Check the gas is connected, check hoses, gas valve and torch are not restricted. Set
the gas ow between 12 - 15 l/min ow rate
Back cap not tted correctly Make sure the torch back cap is tted so that the o-ring is inside the torch body
Torch connected to DC + Connect the torch to the DC- output terminal
Incorrect tungsten being used Check and change the tungsten type if necessary
Tungsten being oxidised after weld
is nished
Keep shielding gas owing 10–15 seconds after arc stoppage. 1 second for each 10
amps of weld current.
2: Contaminated tungsten
Possible Reason Suggested Remedy
Touching tungsten into the weld
pool
Keep tungsten from contacting weld puddle. Raise the torch so that the tungsten is off of
the work piece 2 - 5mm
Touching the ller wire to the tung-
sten
Keep the ller wire from touching the tungsten during welding, feed the ller wire into the
leading edge of the weld pool in front of the tungsten
Tungsten melting into the weld pool Check that correct type of tungsten is being used. Too much current for the tungsten
size so reduce the amps or change to a larger tungsten
3: Porosity - poor weld appearance and colour
Possible Reason Suggested Remedy
Incorrect Gas Check that pure Argon is being used
Inadequate gas ow / gas leaks Check the gas is connected, check hoses, gas valve and torch are not restricted. Set the
gas ow between 6 - 10 l/min ow rate. Check hoses and ttings for holes, leaks etc.,
Moisture on the base metal Remove all moisture from base metal before welding
Contaminated base metal Remove materials like paint, grease, oil, and dirt, including mill scale from base metal
Contaminated ller wire Remove all grease, oil, or moisture from ller metal.
Incorrect ller wire Check the ller wire and change if necessary
4: Yellowish residue / smoke on the alumina nozzle & discoloured tungsten
Possible Reason Suggested Remedy
Incorrect Gas Use pure Argon gas
Inadequate gas ow Set the gas ow between 6 - 10 l/min ow rate
Alumina gas nozzle too small for size
of tungsten being used
Increase the size of the alumina gas nozzle
5: Unstable Arc during DC welding
Possible Reason Suggested Remedy
Torch connected to DC + Connect the torch to the DC- output terminal
Contaminated base metal Remove materials like paint, grease, oil, and dirt, including mill scale from base metal.
Tungsten is contaminated Remove 10mm of contaminated tungsten and re grind the tungsten
Arc length too long Lower torch so that the tungsten is off of the work piece 2 - 5mm
The following chart addresses some of the common problems of DC TIG welding. In all cases of equipment malfunction, the
manufacturer’s recommendations should be strictly adhered to and followed.
TIG WELDING TROUBLE SHOOTING
7: Arc wanders during DC welding
Possible Reason Suggested Remedy
Poor gas ow Check and set the gas ow between 6 - 10 l/min ow rate
Incorrect arc length Lower torch so that the tungsten is off of the work piece 2 - 5mm
Tungsten incorrect or in poor condi-
tion
Check that correct type of tungsten is being used. Remove 10mm from the weld end of
the tungsten and re sharpen the tungsten
Poorly prepared tungsten Grind marks should run lengthwise with tungsten, not circular. Use proper grinding
method and wheel.
Contaminated base metal Remove contaminating materials like paint, grease, oil, and dirt, including mill scale from
base metal.
Contaminated ller wire Remove all grease, oil, or moisture from ller metal.
Incorrect ller wire Check the ller wire and change if necessary