Impax IM-MULT160-K Instruction Manual page 45

TIG OPERATION
TIG Welding with Filler Wire Technique It is necessary in many situations with TIG
Fig 41
welding to add a filler wire into the weld pool to
build up weld reinforcement and create a strong
weld. Once the arc is started the torch tungsten
is held in place until a weld pool is created, a
circular movement of the tungsten will assist is
creating a weld pool of the desired size. Once
the weld pool is established tilt the torch at
about a 75° angle and move smoothly and
evenly along the joint. The filler metal is
introduced to the leading edge of the weld pool.
The filler wire is usually held at about a 15°
angle and fed into the leading edge of the
molten pool, the arc will melt the filler wire into
the weld pool as the torch is moved forward.
Also a dabbing technique can be used to
control the amount of filler wire added, the wire
is fed into the molten pool and retracted in a
repeating sequence as the torch is moved slowly
and evenly forward. It is important during the
welding to keep the molten end of the filler wire
inside the gas shield as this protects the end of
the wire from being oxidized and contaminating
the weld pool. Fig 41.
TIG (GTAW) Basic Welding Guide
Gas Tungsten Arc Welding (GTAW) or TIG
(Tungsten Inert Gas) as it is commonly referred
to, is a welding process in which fusion is
produced by an electric arc that is established
between a single tungsten (nonconsumable)
electrode and the work piece. Shielding is
obtained from a welding grade shielding gas or
welding grade shielding gas mixture which is
generally Argon based. A filler metal may also
be added manually in some circumstances
depending on the welding application.
DC TIG Welding
The TIG (Tungsten lnert Gas) welding process is
based on the presence of an electric arc
between a non-consumable electrode (pure or
alloyed tungsten with an approximate melting
temperature of 3370°C) and the workpiece. An
inert gas (typically argon) atmosphere protects
the weld pool.
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