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RAZOR TIG 200 ACDC
OPERATING MANUAL
Tungsten Electrodes
• Tungsten is a rare metallic element used for manufacturing TIG welding electrodes. The TIG process relies
on tungsten’s hardness and high-temperature resistance to carry the welding current to the arc. Tungsten
has the highest melting point of any metal, 3,410 degrees Celsius.
• Tungsten electrodes are non-consumable and come in a variety of sizes. They are made from pure tungsten
or an alloy of tungsten and other rare earth elements. Choosing the correct tungsten depends on the
material being welded, the number of amps required and whether you are using AC or DC welding current.
• Tungsten electrodes are colour-coded at the end for easy identification.
• Below are the most commonly used tungsten electrodes found in the New Zealand and Australian market.
Thoriated (Colour Code: Red)
Thoriated tungsten electrodes (AWS classification EWTh-2) contain a minimum of 97.30 % tungsten and 1.70
to 2.20 % thorium and are called 2 % thoriated. They are the most commonly used electrodes today and are
preferred for their longevity and ease of use. Thorium, however, is a low-level radioactive hazard and many
users have switched to other alternatives. Regarding the radioactivity, thorium is an alpha emitter, but when
it is enclosed in a tungsten matrix, the risks are negligible. Thoriated tungsten should not get in contact with
open cuts or wounds. The more significant danger to welders can occur when thorium oxide gets into the
lungs. This can happen from the exposure to vapours during welding or ingestion of material/dust in the
grinding of the tungsten. Follow the manufacturer’s warnings, instructions, and the Material Safety Data Sheet
(MSDS) for its use.
Rare Earth (Colour Code: Purple)
Rare Earth tungsten electrodes (AWS classification EWG) contain a minimum of 98% % tungsten and up to 1.5
% Lanthanum and small percentages of zirconium and yttrium they are called Rare Earth tungsten. Rare Earth
tungsten electrodes provide conductivity similar to that of thoriated electrodes. Typically, this means that Rare
Earth tungsten electrodes are exchangeable with thoriated electrodes without requiring significant welding
process changes. Rare Earth delivers superior arc starting, electrode lifetime, and overall cost-effectiveness.
When Rare Earth tungsten electrodes are compared with 2% thoriated tungsten, Rare Earth requires fewer
re-grinds and provides a longer overall lifetime. Tests have shown that ignition delay with Rare Earth tungsten
electrodes improve over time, while 2% thoriated tungsten starts to deteriorate after only 25 starts. At
equivalent energy output, Rare Earth tungsten electrodes run cooler than 2% thoriated tungsten, thereby
extending overall tip lifetime. Rare Earth tungsten electrodes work well on AC or DC. They can be used DC
electrode positive or negative with a pointed end, or balled for use with AC power sources.
Ceriated (Colour Code: Orange)
Ceriated tungsten electrodes (AWS classification EWCe-2) contain a minimum of 97.30% tungsten and 1.80
to 2.20% cerium and are referred to as 2% ceriated. Ceriated tungstens perform best in DC welding at low
current settings. They have excellent arc starts at low amperages and become popular in such applications as
orbital tube welding and thin sheet metal work. They are best used to weld carbon steel, stainless steel, nickel
alloys, and titanium. In some cases, it can replace 2% thoriated electrodes. Ceriated tungsten is best suited for
lower amperages it should last longer than a Thoriated tungsten. Higher amperage applications are best left
to Thoriated or Lanthanated tungstens.
Lanthanated (Colour Code: Gold)
Lanthanated tungsten electrodes (AWS classification EWLa-1.5) contain a minimum of 97.80 % tungsten and
1.30 % to 1.70 % lanthanum and are known as 1.5 % lanthanated. These electrodes have excellent arc starting,
a low burn-off rate, good arc stability, and excellent re-ignition characteristics. Lanthanated tungstens also
share the conductivity characteristics of 2 % thoriated tungsten. Lanthanated tungsten electrodes are ideal
if you want to optimise your welding capabilities. They work well on AC or DC electrode negative with a
pointed end, or they can be balled for use with AC sine wave power sources. Lanthanated tungsten maintains
a sharpened point well, which is an advantage for welding steel and stainless steel on DC or AC from square
wave power sources.
Zirconiated (Colour Code: White)
Zirconiated tungsten electrodes (AWS classification EWZr-1) contain a minimum of 99.10 % tungsten and 0.15 to
0.40 % zirconium. Most commonly used for AC welding, Zirconiated tungsten produces a very stable arc and is
resistant to tungsten spitting. It is ideal for AC welding because it retains a balled tip and has a high resistance
to contamination. Its current-carrying capacity is equal to or greater than that of thoriated tungsten. Zirconiated
tungsten is not recommended for DC welding.
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