PRO-POINT MIG-ARC-TIG 145A Manuel De L'utilisateur page 26

8619470
THORIATED
(Colour Code: Red)
WARNING! Thoriated tungsten should not come 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
Safety Data Sheet (SDS) for its use.
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 increases
the electron emission qualities of the electrode, which improves arc starts and allows for a
higher current-carrying capacity. This electrode operates far below its melting temperature,
which results in a considerably lower rate of consumption and eliminates arc wandering for
greater stability. Compared with other electrodes, thoriated electrodes deposit less tungsten
into the weld puddle, so they cause less weld contamination.
However, thorium 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. Thus holding a stick of Thoriated tungsten in your hand should
not pose a great threat unless a welder has open cuts on their skin.
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 tungsten's
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% 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
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 tungsten also shares the conductivity characteristics of 2%
thoriated tungsten. Lanthanated tungsten electrodes are ideal if you want to optimize 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
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.
TUNGSTEN ELECTRODES RATING FOR WELDING CURRENTS
TUNGSTEN DIAMETER
3/64 in. (1.2 mm)
1/16 in. (1.6 mm)
3/32 in. (2.4 mm)
1/8 in. (3.2 mm)
5/32 in. (3.9 mm)
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145A MULTI-PROCESS MIG-ARC-TIG WELDER
(Color Code: Gold)
(Color Code: White)
DC CURRENT AMPS TORCH
NEGATIVE 2% THORIATED
15 – 80A
70 -150A
150- 250A
250 – 400A
400 – 500A
AC CURRENT AMPS UNBALANCED
WAVE 0.8% ZIRCONIATED
15 – 80A
70 – 150A
140 – 235A
225 – 325A
300 – 400A
For technical questions call 1-800-665-8685
AC CURRENT AMPS BALANCED
WAVE 0.8% ZIRCONIATED
20 – 60A
60 – 120A
100 – 180A
160 – 250A
200 – 320A
V1.0
Table 4