Tweco 160 TS Arcmaster - Manual (Page 43)

ARCMASTER ® 160TS
March 31, 2006 9-3
Figure 8 – Example of insuffi cient gap or incorrect sequence
4. Portions of the weld run
do not fuse to the surface
of the metal or edge of the
joint.
A.
B.
Small electrodes used on heavy
cold plate.
Welding current is too low.
A
.
B.
Use larger electrodes and pre-heat the
plate.
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.
Figure 9 – Example of lack of fusion
5. Non-metallic parti cles 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 suffi cient 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 diffi cult.
Figure 10 – Examples of slag inclusion