Lincoln Electric 575 manual Operation, For Tungsten Electrodes

B-7				OPERATION				B-7
			Table B.3 TYPICAL CURRENT RANGES (1)
			FOR TUNGSTEN ELECTRODES (2)
		DCEN (-)	DCEP (+)		Approximate Argon Gas Flow Rate
					l/min (c.f.m.)
Tungsten
Electrode		1%, 2%	1%, 2%					TIG TORCH
Diameter		Thoriated	Thoriated		Aluminium	Stainless Steel		Nozzle
mm (in)		Tungsten	Tungsten					Size (4), (5)
.25	(0.010)	2-15	(3)		2-4 (3-8)	2-4 (3-8)		#4, #5, #6
.50	(0.020)	5-20	(3)		3-5 (5-10)	3-5	(5-10)
1.0	(0.040)	15-80	(3)		3-5 (5-10)	3-5	(5-10)
1.6	(1/16)	70-150	10-20		3-5 (5-10)	4-6	(9-13)	#5, #6
2.4	(3/32)	150-250	15-30		6-8 (13-17)	5-7 (11-15)		#6, #7, #8
3.2	(1/8)	250-400	25-40		7-11 (15-23)	5-7 (11-15)
4.0	(5/32)	400-500	40-55		10-12 (21-25)	6-8 (13-17)		#8, #10
4.8	(3/16)	500-750	55-80		11-13 (23-27)	8-10	(18-22)
6.4	(1/4)	750-1000	80-125		13-15 (28-32)	11-13 (23-27)

(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.	6 mm
# 5 =	5/16 in.	8 mm
# 6 =	3/8 in.	10 mm
# 7 =	7/16 in.	11 mm
# 8 =	1/2 in.	12.5 mm
#10 =	5/8 in.	16 mm

(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.

Vantage 575