Xcel-Arc Viper ARC140V, Руководство оператора

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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 nonconsumable 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, 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
Thoriated tungsten electrodes (AWS classification EWTh-2) contain a minimum of 97.30 percent tungsten and 1.70 to 2.20
percent thorium and are called 2 percent 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 from
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.
E3
(Color Code: Purple)
E3 tungsten electrodes (AWS classification EWG) contain a minimum of 98% percent tungsten and up to 1.5 percent Lantha-
num and small percentages of Zirconium and Yttrium they are called E3 Tungsten. E3 Tungsten Electrodes provide conductiv-
ity similar to that of thoriated electrodes. Typically, this means that E3 Tungsten Electrodes are exchangeable with thoriated
electrodes without requiring significant welding process changes. E3 deliver superior arc starting, electrode lifetime, and
overall cost-effectivenes. When E3 Tungsten Electrodes are compared with 2% thoriated tungsten, E3 requires fewer re-grinds
and provides a longer overall lifetime. Tests have shown that ignition delay with E3 Tungsten Electrodes actually improves over
time, while 2% thoriated tungsten starts to deteriorate after only 25 starts. At equivalent energy output, E3 Tungsten Electrodes
run cooler than 2% thoriated tungsten, thereby extending overall tip lifetime. E3 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 (Color Code: Orange)
Ceriated tungsten electrodes (AWS classification EWCe-2) contain a minimum of 97.30 percent tungsten and 1.80 to 2.20
percent cerium and are referred to as 2 percent ceriated. Ceriated tungstens perform best in DC welding at low current set-
tings. They have excellent arc starts at low amperages and become popular in such applications as orbital tube welding, thin
sheet metal work. They are best used to weld carbon steel, stainless steel, nickel alloys, and titanium, and in some cases
it can replace 2 percent thoriated electrodes. Ceriated tungsten is best suited for lower amperages it should last longer than
Thoriated tungsten higher amperage applications are best left to Thoriated or Lanthanated tungsten.
Lanthanated (Color Code: Gold)
Lanthanated tungsten electrodes (AWS classification EWLa-1.5) contain a minimum of 97.80 percent tungsten and 1.30
percent to 1.70 percent lanthanum, and are known as 1.5 percent 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 conduc-
tivity characteristics of 2 percent 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
(Color Code: White)
Zirconiated tungsten electrodes (AWS classification EWZr-1) contain a minimum of 99.10 percent tungsten and 0.15 to 0.40
percent 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.
Tungsten Electrodes Rating for Welding Currents
Tungsten DC Current Amps AC Current Amps AC Current Amps
Diameter Torch Negative Un-Balanced Wave Balanced Wave
mm 2% Thoriated 0.8% Zirconiated 0.8% Zirconiated
1.0mm 15 - 80 15 - 80 20 - 60
1.6mm 70 -150 70 - 150 60 - 120
2.4mm 150- 250 140 - 235 100 - 180
3.2mm 250 - 400 225 - 325 160 - 250
4.0mm 400 - 500 300 - 400 200 - 320