Rtech Tig200, Руководство по эксплуатации

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3.2 C-Mn Steel
TIG welding may be used for welding carbon
steel but because deposition rates are low, it
is usually only used for welding sheet and thin
sections for high quality applications, small
components, and root passes of multipass butt
joints in plate and pipe.
Standard DC TIG equipment is normally
suitable and DCEN polarity is usually chosen to
provide good workpiece heating.
Only inert or reducing gases should be used
for TIG welding and pure argon is normally
recommended as the shielding gas for steel.
Filler rods are usually selected to match the
chemical composition and the mechanical
properties of the parent plate.The weldability of
the steel may impose restrictions on the choice
of filler rod.
Steels with carbon contents above about 0.3%
are hardenable, and fast cooling will produce a
hard HAZ and this is liable to result in
hydrogen cracking.This form of cracking can
be prevented by use of preheat and suitable
welding procedures.