Xcel-Arc RazorWeld Razor TIG320 ACDC, Руководство по эксплуатации

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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
Tungsten Electrodes Rating for Welding Currents
Tungsten Electrodes
Tungsten is a rare metallic element used for manufacturing TIG welding electrodes. The TIG process relies on tungsten’s hard-
ness 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 identifica
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tion. 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: Turquoise)
E3 tungsten electrodes (AWS classification EWG) contain a minimum of 98% percent tungsten and up to 1.5 percent Lanthanum
and small percentages of Zirconium and Yttrium they are called E3 Tungsten. E3 Tungsten Electrodes provide conductivity 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: Grey)
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 settings. 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 ap-
plications 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 conductivity 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. Lanthan-
ated 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 per
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cent 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.