Tweco Fabricator 141i Operating Manual - Manual (Page 82)

Fabricator 141i
BASIC WELDING GUIDE 4-22 Manual 0-5145
FAULT CAUSE REMEDY
5 Portions of the
weld run do not
fuse to the surface
of the metal or
edge of the joint.
A Small electrodes used on
heavy cold plate.
A Use larger electrodes and preheat the plate.
B Welding current is too low. B Increase welding current.
C Wrong electrode angle. C Adjust angle so the welding arc is directed more
into the base metal.
D Travel speed of electrode is
too high.
D Reduce travel speed of electrode.
E Scale or dirt on joint surface. E Clean surface before welding.
Art # A-05867_AC Lack of
inter-run fusion
Lack of side fusion,
scale dirt, small electrode,
amperage too low
Lack of root fusion
Lack of fusion caused by dirt,
electrode angle incorrect,
rate of travel too high
Figure 2: Example of Lack of Fusion
6 Gas pockets or
voids in weld
metal (porosity)
A High levels of sulfur in steel. A Use an electrode that is designed for high sulfur
steels.
B Electrodes are damp. B Dry electrodes before use.
C Welding current is too high. C Reduce welding current.
D Surface impurities such as
oil, grease, paint, etc.
D Clean joint before welding.
E Welding in a windy environ-
ment.
E Shield the weld area from the wind.
F Electrode damaged ie flux
coating incomplete.
F Discard damaged electrodes and only use elec-
trodes with a complete flux coating.
7 Crack occurring in
weld metal soon
after solidification
commences
A Rigidity of joint. A Redesign to relieve weld joint of severe stresses or
use crack resistance electrodes.
B Insufficient throat thickness. B Travel slightly slower to allow greater build up in
throat.
C Weld current is too high. C Decrease welding current.
Not cleaned,
or incorrect
electrode
Slag
trapped in
undercut
Slag trapped in root
Art # A-05868_AC
Figure 3: Example of Slag Inclusion
8 The Stick elec-
trode is difficult to
run with multiple
arc-outs when
welding
The Stick electrode being
used is not suitable for use
with this machine.
Use E6013 or E7018 Stick electrodes for steel or
300 series stainless steel Stick electrodes for 300
series stainless steel.
Table 4-5: Welding Problems - Stick (SMAW)