Hobart 180 SD Welding System User Manual


 
OM-355 Page 22
SECTION 7 SELECTING AND PREPARING
TUNGSTEN ELECTRODE
gtaw2 7/97
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.
NOTE
7-1. Selecting Tungsten Electrode
Amperage Range - Gas Type - Polarity
Electrode Diameter DC Argon Electrode Negative/Straight
Polarity
DC Argon Electrode Positive/Reverse
Polarity
2% Thorium Alloyed Tungsten (Red
Band)
.010 Up to 25 *
.020 15-40 *
.040 25-85 *
1/16 50-160 10-20
3/32 135-235 15-30
1/8 250-400 25-40
5/32 400-500 40-55
3/16 500-750 55-80
1/4 750-1000 80-125
Typical argon shielding gas flow rates are 15 to 35 cfh (cubic feet per hour) 7 to 16.5 lpm (liters per minute).
*Not Recommended.
The figures listed are intended as a guide and are a composite of recommendations from American Welding Society (AWS) and electrode
manufacturers.
7-2. Safety Information About Tungsten
Ref. S-0161
Y Grinding the tungsten elec-
trode produces dust and fly-
ing sparks which can cause
injury and start fires. Use lo-
cal exhaust (forced ventila-
tion) at the grinder or wear an
approved respirator. Read
MSDS for safety information.
Consider using tungsten
containing ceria, lanthana,
or yttria instead of thoria.
Grinding dust from thoriated
electrodes contains low-lev-
el radioactive material.
Properly dispose of grinder
dust in an environmentally
safe way. Wear proper face,
hand, and body protection.
Keep flammables away.
1 Tungsten Electrode With
Balled End
2 Pointed Tungsten Electrode
1
2