Rtech Tig200, Руководство по эксплуатации

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3.7 Copper and Copper Alloys
Cleanliness is important when welding copper,
and all dirt, grease, and other contaminants
must be removed before welding. Copper
alloys containing aluminium will form a surface
oxide film and this must also be removed
before welding. Preheat will be required for
unalloyed copper but some copper alloys can
be TIG welded without preheat except on thick
sections.
Standard DC TIG welding equipment is
suitable for most copper and copper alloys, but
aluminium bronze is normally TIG welded using
AC current to break down the tenacious oxide
film on the surface.
Pure argon, helium, or argon-helium mixtures
are standard shielding gases for DC TIG welding
copper and copper alloys.Alushield Heavy is
ideal for TIG welding copper and some copper
alloys, particularly in thicker sections. Pure
argon is the shielding gas used for AC TIG
welding.
TIG consumables are solid filler rods based
on pure copper and several copper alloy
compositions, including aluminium bronzes,
silicon bronzes, and cupro-nickels. It is normal
to try to use a filler material with a similar
composition to that of the parent material but
this is not always possible, and sometimes not
desirable.
Porosity is the main welding problem
encountered when TIG welding unalloyed
copper and some copper alloys are prone to
solidification cracking and porosity. Certain
alloys are difficult to weld (brass will lose zinc if
welding is attempted), and those containing lead
are virtually unweldable.