Tweco 300 DC Arcmaster - Manual (Page 54)

ARCMASTER 300 ACDC
10-4 February 22, 2006
10.02 Stick Welding Problems
A Electrodes are damp. A Dry electrodes before use.
B Welding current is too high. B Reduce welding current.
C Surface impurities such as
oil, grease, paint, etc.
C Clean joint before welding.
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 Cooling rate is too high. C Preheat plate and cool
slowly.
A Welding current is too low. A Increase welding current
B Electrode too large for joint. B Use smaller diameter
electrode.
C Insufficient gap. C Allow wider gap.
D Incorrect sequence. D Use correct build-up
sequence.
Remedy
3 A gap is left by failure
of the weld metal to fill
the root of the weld.
Description Possible Cause
1 Gas pockets or voids
in weld metal
(Porosity).
2 Crack occurring in
weld metal soon after
solidification
commences.
Table 10-2: Stick Welding Problems
Incorrect sequence
Insufficient
gap
Art # A-04991
Figure 10-1: Example of insufficient gap or incorrect sequence