Miller Electric MARK VIII-2 manual Selecting and Preparing Tungsten Electrode

SECTION 8 − SELECTING AND PREPARING

TUNGSTEN ELECTRODE

gtaw 7/97

NOTE

For additional information, see your distributor for a handbook on the Gas Tungsten Arc Welding (GTAW) process.Wear clean gloves to prevent contamination of tungsten electrode.

8-1. Selecting Tungsten Electrode

		Amperage Range - Gas Type♦ - Polarity
Electrode Diameter	DC − Argon − Electrode	DC − Argon − Electrode	AC − Argon − Using	AC − Argon − Balanced
	Negative/Straight Polarity	Positive/Reverse Polarity	High Frequency	Wave Using High Freq.
Pure Tungsten
(Green Band)
.010”	Up to 15	*	Up to 15	Up to 10
.020”	5-20	*	5-20	10-20
.040”	15-80	*	10-60	20-30
1/16”	70-150	10-20	50-100	30-80
3/32”	125-225	15-30	100-160	60-130
1/8”	225-360	25-40	150-210	100-180
5/32”	360-450	40-55	200-275	160-240
3/16”	450-720	55-80	250-350	190-300
1/4”	720-950	80-125	325-450	250-400
2% Thorium Alloyed
Tungsten (Red Band)
.010”	Up to 25	*	Up to 20	Up to 15
.020”	15-40	*	15-35	5-20
.040”	25-85	*	20-80	20-60
1/16”	50-160	10-20	50-150	60-120
3/32”	135-235	15-30	130-250	100-180
1/8”	250-400	25-40	225-360	160-250
5/32”	400-500	40-55	300-450	200-320
3/16”	500-750	55-80	400-500	290-390
1/4”	750-1000	80-125	600-800	340-525
Zirconium Alloyed Tung-
sten (Brown Band)
.010”	*	*	Up to 20	Up to 15
.020”	*	*	15-35	5-20
.040”	*	*	20-80	20-60
1/16”	*	*	50-150	60-120
3/32”	*	*	130-250	100-180
1/8”	*	*	225-360	160-250
5/32”	*	*	300-450	200-320
3/16”	*	*	400-550	290-390
1/4”	*	*	600-800	340-525

♦Typical argon shielding gas flow rates are 15 to 35 cfh (cubic feet per hour). *Not Recommended.

The figures listed are intended as a guide and are a composite of recommendations from American Welding Society (AWS) and electrode manufacturers.

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