Razorweld Xcel-Arc MULTI 230 AC/DC, Руководство по эксплуатации

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Power Source
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DC TIG Welding
The DC power source uses what is known as DC (direct current) in which the main electrical component
known as electrons flow in only one direction from the negative pole (terminal) to the positive pole (terminal).
In the DC electrical circuit, there is an electrical principle at work which should always be taken into account
when using any DC circuit. With a DC circuit, 70% of the energy (heat) is always on the positive side. This
needs to be understood because it determines what terminal the TIG torch will be connected to (this rule
applies to all the other forms of DC welding as well ).
DC TIG welding is a process in which an arc is struck between a tungsten electrode and the metal workpiece.
The weld area is shielded by an inert gas flow to prevent contamination of the tungsten, molten pool and weld
area. When the TIG arc is struck, the inert gas is ionised and superheated, changing its molecular structure,
which converts it into a plasma stream. This plasma stream flowing between the tungsten and the workpiece
is the TIG arc and can be as hot as 19,000°C. It is a very pure and concentrated arc which provides the
controlled melting of most metals into a weld pool. TIG welding offers the user the highest amount of flexibility
to weld the widest range of material thickness and types. DC TIG welding is also the cleanest weld with no
sparks or spatter.
The intensity of the arc is proportional to the current that flows from the tungsten. The welder regulates the
welding current to adjust the power of the arc. Typically thin material requires a less powerful arc with less
heat to melt the material, so less current (amps) is required. Thicker material requires a more powerful arc with
more heat, so more current (amps) are necessary to melt the material.
High Frequency Arc Ignition for TIG (Tungsten Inert Gas) Welding
HF (High Frequency) ignition allows the arc to be started in TIG welding without touching the tungsten to the
work piece. By pressing the torch switch the machine will activate the gas flow and introduce the HF spark,
this "ionises" the air gap making it conductive, allowing an arc to be created without touching the tungsten
to the work piece. The gas molecules are superheated by the arc creating a stream of super heated gas
that changes the molecular structure into producing a plasma stream. This plasma stream provides heat and
energy that allows us to melt and fuse metals in an inert gas shielded environment know as TIG (Tungsten
Inert Gas) welding.
DC TIG WELDING GUIDE
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