OPERATION
B-18
B-18
SQUARE WAVE TIG 355
TABLE B.2
TYPICAL CURRENT RANGES
(1)
FOR TUNGSTEN ELECTRODES
(2)
DCEN (-)
DCEP (+)
Tungsten
1%, 2%
1%, 2%
Electrode
1%, 2%
1%, 2%
Thoriated
Thoriated
TIG Torch
Diameter
Thoriated
Thoriated
Pure
Tungsten
Pure
Tungsten
Stainless
Nozzle
in. (mm)
Tungsten
Tungsten
Tungsten
Zirconated
Tungsten
Zirconiated
Aluminum
Steel
Size
(4), (5)
.010
(.25)
2-15
(3)
2-15
2-15
2-15
—
3-8 (2-4)
3-8 (2-4)
4,5,6
0.020
(.50)
5-20
(3)
5-15
5-20
10-20
5-20
5-10 (3-5)
5-10 (3-5)
0.040
(1.0)
15-80
(
3)
10-60
15-80
20-30
20-60
5-10 (3-5)
5-10 (3-5)
1/16
(1.6)
70-150
10-20
50-100
70-150
30-80
60-120
5-10 (3-5)
9-13 (4-6)
5,6
3/32
(2.4)
150-250
15-30
100-160
140-235
60-130
100-180
13-17 (6-8)
11-15 (5-7)
6,7,8
1/8
(3.2)
250-400
25-40
150-210
225-325
100-180
160-250
15-23 (7-11)
11-15 (5-7)
5/32
(4.0)
400-500
40-55
200-275
300-400
100-240
200-320
21-25 (10-12) 13-17 (6-8)
8,10
3/16
(4.8)
500-750
55-80
250-350
400-500
190-300
290-390
23-27 (11-13) 18-22 (8-10)
1/4
(6.4)
750-1000
80-125
325-450
500-630
250-400
340-525
28-32 (13-15) 23-27 (11-13)
(1) When used with argon gas. The current ranges shown must be reduced when using argon/helium or pure helium shielding gases.
(2) Tungsten electrodes are classified as follows by the American Welding Society (AWS):
Pure .................................EWP
1% Thoriated ..................EWTh-1
2% Thoriated ..................EWTh-2
Though not yet recognized by the AWS, Ceriated Tungsten is now widely accepted as a substitute for 2% Thoriated Tungsten in AC and DC applications.
(3) DCEP is not commonly used in these sizes.
(4) TIG torch nozzle “sizes” are in multiples of 1/16ths of an inch:
# 4 = 1/4 in.
(6mm)
# 5 = 5/16 in.
(8mm)
# 6 = 3/8 in.
(10mm)
# 7 = 7/16 in.
(11mm)
#8 = 1/2 in.
(12.5mm)
#10 = 5/8 in.
(16mm)
(5) TIG torch nozzles are typically made from alumina ceramic. Special applications may require lava nozzles, which are less prone to breakage, but cannot withstand high
temperatures and high duty cycles. Currents above 350 amps require metal nozzles on water cooled torches.
Approximate Argon
Gas Flow Rate
C.F.H. (l/min)
AC
Unbalanced Wave
Balanced Wave
Summary of Contents for SQUARE WAVE IM467-B
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