Tweco 100 Weldskill - Manual (Page 37)

weldskill 100 iNVeRTeR
5-5 March 3, 2008
Description Possible Cause Remedy
6 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
Not cleaned, or incorrect electrode
Slag trapped in
undercut
Slag trapped in root
Art # A-05868
Figure 5-4: Examples of Slag Inclusion