Firepower TIG 200 AC/DC, Operating Manual

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FIREPOWER TIG 200 AC/DC BASIC WELDING GUIDE
4-12 Manual 0-5370 Basic Welding Guide
FAULT CAUSE REMEDY
7 Crack occurring in
weld metal soon
after solidification
commences
A Rigidity of joint. A Redesign to relieve weld joint of severe stresses
or use crack resistance electrodes.
B Insufficient throat thick-
ness.
B Travel slightly slower to allow greater build up in
throat.
C Weld current is too high. C Decrease welding current.
Art: A-04973
Figure 3: Example of Slag Inclusion
Table 4-2: Welding Problems SMAW (STICK)
4.03 TIG (GTAW) BASIC WELDING TECHNIQUE
Gas Tungsten Arc Welding (GTAW) or TIG (Tungsten Inert Gas) as it is commonly referred to, is a welding process
in which fusion is produced by an electric arc that is established between a single tungsten (non-consumable)
electrode and the work piece. Shielding is obtained from a welding grade shielding gas or welding grade shielding
gas mixture which is generally Argon based. A filler metal may also be added manually in some circumstances
depending on the welding application.
Welds Made With or Without
Addition of Filler Metal
Work Piece
Can Be Any Commercial
Metal
Gas Cup
Either Ceramic,
High-lmpact or
Water Cooled
Metal
Inert Gas
Shields Electrode
and Weld Puddle
Tungsten Electrode
Non-Consumable
Art # A-09658_AC
Figure 4-28: TIG Welding Application Shot
Tungsten Electrode Current Ranges
Electrode Diameter DC Current (Amps)
0.040" (1.0mm) 30-60
1/16" (1.6mm) 60-115
3/32" (2.4mm) 100-165
1/8" (3.2mm) 135-200
5/32" (4.0mm) 190-280
3/16" (4.8mm) 250-340
Table 4-3: Current Ranges for Various Tungsten Electrode Sizes