|
TIG
welding electrodes usually contain small quantities of
metallic oxides which can offer the following benefits:
-
Facilitate arc starting
-
Increase arc stability
-
Improve current
carrying capacity of the electrode
-
Reduce
the risk of weld contamination
-
Increase electrode
life
Oxides used are
primarily zirconium, thorium, lanthanum or cerium.
Additions are usually 1% - 4%. These oxides greatly
improve arc initiation, especially when direct current
(DC) welding is employed. Thorium oxide (thoria) has
been used for many years, having been found effective in
terms of long life and thermal efficiency. Zirconium
oxide (zirconia) has been commonly used for alternating
(AC) TIG welding, normally for welding aluminum. |
|
|
ISO Color Chart |
Type |
Part Number |
Size |
|
RED
AWS A5.12 EWTh-2
ISO 6848 WT20
|
2% Thoriated: Best stability at medium currents,
good arc starts, medium tendency to spit, medium erosion rate |
T0207GT2 |
.020 x 7" |
|
T0407GT2 |
.040 x 7" |
|
T1167GT2 |
1/16 x 7" |
|
T3327GT2 |
3/32 x 7" |
|
T187GT2 |
1/8 x 7" |
|
T532GT2 |
5/32 x 7" |
|
|
|
|
|
|
GOLD
AWS A5.12 EWLa-1.5
ISO 6848 WL15
|
1.5% Lanthanated: Lowest erosion rate, wide current range, no
spitting, best DC arc starts and stability |
T0207GL |
.020 x
7" |
|
T0407GL |
.040 x 7" |
|
T1167GL |
1/16 x
7" |
|
T3327GL |
3/32 x 7" |
|
T187GL |
1/8 x
7" |
|
T5327GL |
5/32 x 7" |
|
|
|
|
|
|
GRAY
AWS A5.12 EWCe-2
ISO 6848 WC20
|
2% Ceriated: Low erosion rate, wide current range, AC or DC, no
spitting, consistent arc starts, good stability |
T0207GC2 |
.020 x 7" |
|
T0407GC2 |
.040 x 7" |
|
T1167GC2 |
1/16 x 7" |
|
T3327GC2 |
3/32 x 7" |
|
T187GC2 |
1/8 x 7" |
|
T5327GC2 |
5/32 x 7" |
|
|
|
|
|
WHITE
AWS A5.12 NONE
ISO 6848 WZ8 |
.8% Zirconiated: Balls well, handles higher current with less
spitting, better arc starts and arc stability than pure tungsten |
T0207GZ |
.020 x 7" |
|
T0407GZ |
.040 x 7" |
|
T1167GZ |
1/16 x 7" |
|
T3327GZ |
3/32 x 7" |
|
T187GZ |
1/8 x 7" |
|
T5327GZ |
5/32 x 7" |
|
|
|
|
|
|
GREEN
AWS A5.12 EWP
ISO 6848 WP |
Pure: Balls easily, low cost, tends to spit at higher currents,
used for non-critical welds only |
T0207G |
.020 x 7" |
|
T0407G |
.040 x 7" |
|
T1167G |
1/16 x 7" |
|
T3327G |
3/32 x 7" |
|
T187G |
1/8 x 7" |
|
T5327G |
5/32 x 7" |
|
|
