1 The
consistent production of good, sound welds is not accidental. A thorough knowledge
of the welding process
and its elements is necessary. Knowing how to establish initial welding conditions
is not enough. It is
also necessary to be able to analyze a finished weld and change the welding conditions
if changes are required.
Operating Hints and Procedures
Result: Both welds have excessive penetration
and reinforcement; bottom weld has reinforcement
overlap, undesirable “pear” shape
(bottom wider than top). FIG.
27 - Effect of Varying the Welding Current WELDING
CURRENT SQUARE GROOVE
BUTTJOINT 1/2-in.
Plate 450
SINGLE-VEE GROOVE BUTT JOINT
1-1/2-in. Plate 840
AMPERES 40 Volts 12.5
ipm Result: Insufficient
penetration and reinforcement.
1200 AMPERES 40
Volts 12.5 ipm 1560
AMPERES 40 Volts 12.5
ipm Result: Welds are satisfactory
in all respects. LOW
CORRECT HIGH
350 AMPERES 29
Volts 30 ipm
500 AMPERES 29
Volts 30 ipm
650 AMPERES 29
Volts 30 ipm
