Tweco 300 DC Arcmaster - Manual (Page 56)

ARCMASTER 300 ACDC
10-6 February 22, 2006
5 Non-metallic parti­cles
are trapped in the
weld metal (slag
inclusion).
A Non-metallic particles may
be trapped in undercut from
previous run.
A If bad undercut is present,
clean slag out and cover
with a run from a smaller
diameter electrode.
B Joint preparation too
restricted.
B Allow for adequate
penetration and room for
cleaning out the slag.
C Irregular deposits allow slag
to be trapped.
C If very bad, chip or grind
out irregularities.
D Lack of penetration with
slag trapped beneath weld
bead.
D Use smaller electrode with
sufficient current to give
adequate penetration. Use
suitable tools to remove all
slag from corners.
E Rust or mill scale is
preventing full fusion.
E Clean joint before welding.
F Wrong electrode for position
in which welding is done.
F Use electrodes designed for
position in which welding is
done, otherwise proper
control of slag is difficult.
Description Possible Cause Remedy
Table 10-2 (continued): Stick Welding Problems
Not cleaned, or
incorrect
electrode
Slag trapped in
undercut
Art # A-04993
Slag trapped in root
Figure 10-3: Examples of slag inclusion