Plasma Arc Welding PAW

Portable manual or automated a.c. or d.c. systems d.c. system most common. 

Choice of gas and their proportions Important for two modes of operation  

Plasma arc cutting for cutting, slotting and profiling materials up to about 40 mm thickness using the key-holing mode of operation. 

High quality welds possible with little or no distortion. 

Tungsten inclusions from eiectrode not present in welds, unlike TIG. 

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Plasma arc welding (PAW) is also applicable to the welding of titanium and tit um alloys. It is faster than GTAW and can be used on thicker sections, such as one-pass welding of titanium alloy plate up to 13 mm (V2 in.) thick, using square-groove butt joints and the key-hole technique. 

Plasma arc welding (PAW) Similar to TIG welding, except that the arc and Metal fumes, ozone, nitrogen... 

Plasma Arc Welding. In the transferred-arc mode of the PAW process, shown in Figure lc, the arc is between a nonconsumable electrode and the base metal, in a manner similar to the GTAW process. The unique feature is the flow of inert gas around the electrode and through a restricted orifice, which constricts the arc to form a plasma jet. A second, outer stream of shielding gas protects the molten metal from atmospheric contamination. In the nontransferred arc mode of the PAW process, the arc is between the electrode and the constricting orifice. This mode is used for plasma spraying... 

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