4. OPERATION DISTURBANCES
The most common operation disturbances are as follows:
Welding wire does not run smoothly or wire is sticking in the wire liner (arc length varies,
you can feel shaking in the handle):
• Wire liner is dirty or blocked-up. Clean with compressed air. Replace
wire liner if necessary.
• Wrong wire liner or contact tip. Make sure that wire liner and contact
tip are according to recommendations for the welding wire in question.
• Contact tip has heatened up too much.
• Contact face of contact tip is damaged due to spatter or sparking
caused by impurities. Replace contact tip.
• Gun cable has too sharp bends, straighten.
• Welding wire has a lot of dirt, rust or bends etc., which increases
friction and results in contact disturbances.
• Check operation of the wire feed unit. Check that drive roll size and
type are suitable for wire in question. Check that drive roll pressure is
not too low or too high.
Gas shielding is bad(weld pool "is boiling", arc is unstable):
• On inner face of gas nozzle or in contact tip and contact tip holder
there is too much welding spatter; clean.
• In discharge hole for shielding gas there is spatter or other dirt; clean.
• There are impurities in shielding gas (moisture, air).
• There are impurities in base material (rust, base coat, grease).
• Pressure gathered in long gas hoses will cause a great ow of
shielding gas at welding start, which may cause turbulence or mixing
of air into shielding gas. The reason may also be a faulty or a faulty
regulated relief valve which lets too much pressure into gas hoses.
• Flow of shielding gas is too small or too big (causes turbulence). Use
in short arc range a ow of 8 - 15 l/min, in hot arc range 10 - 20 l/min.
