Weldclass WeldForce WF-180MST, Operating Instructions Manual

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TIG Welding is a fusion procedure that uses an
electric ARC created between an infusible tungsten
electrode and base material to be welded. For TIG
welding an inert gas must be used (Argon) which
protects the welding bead. If filling material is
used, it is made up of rods suitable to the material
to be welded (steel, stainless steel, copper etc).
In TIG mode, welding is possible in all positions:
flat, angle, on the edge, vertical and overhead.
Furthermore, with respect to other types of
welding, the welding joint has greater mechanical
resistance, greater corrosion resistance and limited
heating in the welded area which limits distortion.
Welding can be done even without weld material,
guaranteeing a smooth, shiny weld with no
impurities or slag.
TIG Basic
Welding Guide
Electric Current
Inert Gas
Tungsten Electrode
Deposit
Melted Area
Penetration
Base Material
Protective Gas
Rod
Torch
TIG Welding
(Fig 15)
TIG Electrode Selection
and Preparation
Electrode Polarity
Connect the TIG torch to the negative (-) torch
terminal and the work lead to the positive (+) work
terminal for direct current straight polarity. Direct
current straight polarity is the most widely used
polarity for DC TIG welding. It allows limited
wear of the electrode since 70% of the heat is
concentrated at the work piece.
Tungsten Electrode
Tapered End
2.5 x Electrode Diameter
(Fig 16-1)
(Fig 16-2)
Stable ARC
Grinding
Wheel
Flat
Straight Ground
2.5 x Electrode Diameter
Grind end of tungsten on fine grit, hard abrasive
wheel before welding. Do not use wheel for other
jobs or tungsten can become contaminated
causing lower weld quality.
Ideal Tungsten Preparation - Stable ARC
Diameter of the flat determines amperage capacity.
Preparing Tungsten for DC Electrode Negative
(DCEN) Welding