AUTO ARC 120 - WELDING DEFECTS: SPATTER, FUSION, AND PENETRATION

Table
7-2.
Excessive
Spatter
-
:. .
~:



Excessive
Spatter

scattering
of
molten metal
particles
that
cool
to
~
~.
solid
form
near
weld bead.
S-0836
Possible Causes
Corrective
Actions
Wire feed
speed
too
high.
Select
lower wire
feed
speed.
Voltage
too
high.
Select lower
voltage
range.
Electrode
extension
(stickout)
too
long.
Use shorter
electrode
extension
(stickout).
Workpiece
dirty.
Remove
all
grease,
oil,
moisture,
rust,
paint,
undercoating,
and dirt
from
work
surface before
welding.
Insufficient
shielding
gas
at
welding
arc.
Increase flow
of
shielding
gas
at
regulator/flowmeter
and/or
prevent
drafts
near
welding
arc.
Dirty
welding
wire.
Use
clean,
dry
welding
wire.
Eliminate
pickup
of
oil
or
lubricant
on
welding
wire
from feeder
or
liner.
Table
7-3.
Incomplete
Fusion
Incomplete
Fusion

failure of weld
metal
to
fuse
completely
with
base
metal
or a
preceeding
weld
bead.
S-0637
Possible Causes
Corrective
Actions
Workpiece dirty.
Remove
all
grease,
oil,
moisture,
rust,
paint,
undercoating,
and dirt
from
work
surface
before
welding.
Insufficient heat
input.
Select
higher voltage
range
and/or
adjust
wire
feed
speed.
Improper
welding
technique.
Place
stringer
bead
in
proper
location(s)
at
joint during
welding.
.
Adjust
work
angle
or
widen
groove
to
access
bottom
during
welding.
Momentarily
hold
arc on
groove
side
walls
when
using
weaving
technique.
Keep
arc
on
leading
edge
of
weld
puddle.
Use
correct
gun
angle
of
0
to
15
degrees.
Lack
Of
Penetration

shallow
fu
sion
between
weld
metal and base
metal.
Table
7-4.
Lack
Of
Penetration
Lack
of
Penetration
Good
Penetration
S~o63e
Possible
Causes
Corrective
Actions
Improper
joint
preparation.
Material
too
thick. Joint
preparation
and
design
must
provide
access
to
bottom of
groove
while
maintain.
ing
proper
welding
wire extension
and
arc
characteristics.
Improper
weld
technique.
Maintain
normal
gun
angle
of
0
to
15
degrees
to
achieve
maximum
penetration.
Keep
arc on
leading edge
of weld
puddle.
Be
sure
welding
wire extends
not
more
than
1/2
in
(13
mm)
beyond
nozzle.
Insufficient heat
input.
Select
higher
wire
feed
speed
and/or
select
higher voltage
range.
Reduce travel
speed.
OM-151
015
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