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DYNA MMA 500S
、
500GTS
、
500(H)S
、
500(H)GTS
、
630S
、
630GTS Operating Manual
9.02 TIG welding problems
Weld quality is dependent on the selection of the correct consumables, maintenance of equipment and proper
welding technique.
Description Possible
Cause
Remedy
1. Excessive bead build-up
or poor penetration or poor
fusion at edges of weld.
Welding current is too low.
Increases weld current, and/ or faulty
joint preparation.
2. Weld bead too wide and
flat or undercut at edges of
weld or excessive burn
through.
Welding current is too high.
Decreases weld current.
3. Weld bead too small or
insufficient penetration or
ripples in bead are widely
spaced apart.
Travel speed too fast.
Reduce weld speed.
4. Weld bead too wide or
excessive bead build up or
excessive penetration in
butt joint.
Travel speed too low.
Increase travel speed.
5. Uneven leg length in fillet
joint.
Wrong placement of filler rod.
Re-position filler rod.
6. Dirty weld pool.
A Electrode contaminated through
contact with work piece or filler
rod material.
B Gas contaminated with air.
A Clean the electrode by grinding off
the contaminates.
B Check gas lines for cuts and loose
fitting or change gas cylinder.
7. Electrode melts or oxidizes
when an arc is struck.
A Electrode is connected to the “+”
terminal.
B No gas flowing to welding region.
C Torch is clogged with dust.
D Gas hose is cut.
E Gas passage contains impurities.
F Gas regulator turned off.
G Torch valve is turned off.
H The electrode is too small for the
welding current.
A Connected the electrode to the “-”
terminal.
B Check the gas lines for kinks or
breaks and gas cylinder contents.
C Clean torch.
D Replace gas hose.
E Dismantle a soft tube from the
torch then raise gas pressure and
blow out impurities.
F Turn
on.
G Turn on.
H Increase electrode diameter or
reduce the welding current.
8. Poor weld finish.
Inadequate shielding gas.
Increase gas flow or check gas line for
gas flow problems.
9. Arc flutters during TIG
welding.
A Tungsten electrode is too large
for the welding current.
B Absence of oxides in the weld
pool.
A Select the right size electrode.
Refer to basic TIG welding guide.
B Refer basic TIG welding guide for
ways to reduce arc flutter.
10. Welding arc can not be
established.
A Work clamp is not connected to
the work piece or the work/ torch
leads are not connected to the
right welding terminals.
B Torch lead is disconnected.
C Gas flow incorrectly set, cylinder
empty or the torch valve is off.
A Connect the work clamp to the
work piece or connect the work/
torch leads to the right welding
terminals.
B Connect it to the “
−
” terminal.
C Select the right flow rate, change
cylinders or turn torch valve on.
