MetFab - Welding Fume Handbook - Flipbook - Page 43
12 Recommended gases
12.2 Stainless steel welding
MIG
lnomaxx® Plus is the optimum gas for
welding all thicknesses of stainless
steels and is particularly beneficial
when high deposition rates are required.
lnomaxx® 2 is also recommended for
welding all thicknesses of stainless.
Environmental
None of the shielding gases normally
used for welding stainless steels offers
significant advantages in reducing
particulate fume emissions.
A shielding gas containing 98%
argon/2% oxygen provides lower
exposure to ozone than any of the
other gases when using both pulsed
and spray transfer. However, lnomaxx®
Plus offers higher productivity without
considerably increasing exposure to
ozone.
The overall preference is therefore for
lnomaxx® Plus.
with carbon dioxide, but exposure to
ozone is not expected to present a major
problem during FCAW of stainless steel.
TIG
lnomaxx® TIG is recommended
for welding austenitic stainless
steels. Argon or Alumaxx® Plus are
recommended for welding ferritic
stainless steels.
Environmental
TIG welding generates only minimal
amounts of particulate fume. Reduced
fume generation is therefore not a
consideration for choosing a shielding
gas for TIG welding.
Argon/helium mixtures (Alumaxx®
Plus) and shielding gases containing
small amounts of hydrogen (lnomaxx®
TIG) offer reduced ozone emissions,
making them the preferred gases
environmentally as well as in terms of
welding characteristics.
FCAW
80% argon/20% co, is the recommended
gas mixture for all applications.
Environmental
At their optimum welding condition,
carbon dioxide, 80% argon/20% CO, and
an experimental mixture containing
35%Ar/50%He/15%CO, all have very
similar particulate fume emission rates.
However, the experimental mixture
provides superior fume reducing
properties over a range of welding
conditions, and is therefore
recommended. More ozone is generated
when welding with this mixture than
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