CIGWELD WELDSKILL 200HF, Operating Manual

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OPERATING MANUAL
200HF
OPERATION 6-10 Manual 0-5406
E. Preheating
Suitable preheating of parts of the structure other
than the area to be welded can be sometimes used
to reduce distortion. Figure 6-23 shows a simple
application. By removing the heating source from b
and c as soon as welding is completed, the sections
b and c will contract at a similar rate, thus reducing
distortion.
Art # A-07707
Figure 6-22: Principle of presetting
Art # A-07708
B
Preheat Preheat
Dotted lines show effect if no preheat is used
Weld
C
Figure 6-23: Reduction of distortion by preheating
Art # A-07709
Figure 6-24: Examples of distortion
Art # A-07710_AB
1
Block Sequence.
The spaces between the welds are
filled in when the welds are cool.
2
3
Figure 6-25: Welding sequence
Art # A-07711_AB
4
3
2
1
Figure 6-26: Step back sequence
Art # A-07712
Figure 6-27: Chain intermittent welding
Art # A-07713_AB
Figure 6-28: Staggered intermittent welding