About Hastelloy C276
Hastelloy
C276 is an alloy made of nickel-chromium-molybdenum that is very versatile and
has resistance to corrosion. This alloy is suitable for many chemical process
applications in the as welded condition due to its resistance to the formation
of grain boundary precipitates in the weld heat-affected zone. Alloy C276 has
resistance to stress-corrosion cracking, pitting and oxidizing atmospheres up
to 1900°F. Alloy C276 has resistance to various chemical environments.
Features
of Hastelloy C276 that make it
highly useful are
·
It has high resistance to strong solutions of oxidizing salts
such as cupric and ferric chlorides.
·
It is resistant to wet chloride gas.
·
It has resistance to hypochlorite and chlorine dioxide
solutions.
·
It is appropriate for many chemical process applications as
it is not prone to grain boundary precipitation in the as welded condition.
·
It has resistance to various chemical process environments
such as dry chlorine, acetic anhydride, hypochlorite & chlorine dioxide
solutions, formic & acetic acids, sea water & brine solutions, ferric
& cupric chlorides, solvents, ferric & cupric chlorides, chlorine &
chlorine contaminated (both organic & inorganic).
·
It has resistance to pitting & stress corrosion cracking.
Applications
of Hastelloy C276 bar are
·
Sulfuric acid reactors.
·
Components exposed to sour gas.
·
Digesters and bleach plants in the paper industry.
·
Equipment for processes utilizing halide or acid catalysts.
·
Equipment for flue-gas desulfurization plants.
·
Organic chloride process equipment.
·
Evaporators, heat exchangers, filters and mixers used in
sulfuric acid environments.
HastelloyC276 is typically used in petrochemical organic chloride & chemical
processes and processes utilizing halide or acid catalysts. Other industrial
applications are
·
Pulp and paper (digesters & bleach areas)
·
Pharmaceutical
·
Scrubbers
·
Food processing equipment
·
Scrubbers and ducting for flue gas desulfurization
·
Oil & Gas
·
Geothermal
·
Chemical Process
·
Solar Power
·
Biomass
·
Petrochemical
·
Utilities
·
Water Desalination
·
Nuclear Power
·
Sea Water
·
Mining
·
LNG (Liquefied Natural Gas)
Cold & hot working of Hastelloy C276
Hastelloy
C276 can be formed using various cold and hot working processes. Hastelloy C276
can be cold formed using aggressive methods such as press forming, deep-drawing
or punching. Hot forming should be done within a temperature range between 1600°F
and 2250°F with heavier sections heated to a minimum of 2000°F before forming.
Annealing of the material after working should be done within a temperature
range of 2050°F to 2150°F followed by a rapid quench in a protective atmosphere
or in an agitated reducing quench bath. 2% Ethyl or Propyl alcohol is added to
water to obtain a reducing media.
Hastelloy C276 for pulp & paper industry
The
pulp & paper industry uses wood as a raw material to make paper, pulp,
board and other cellulose-based products using bleaching vessels and digesters.
Bleaching vessels are used to bleach the wood pulp to make it look whiter and
digesters are used to heat wood chips to high temperatures with sodium sulfide
and sodium hydroxide to change these into pulp by dissolving the wood’s lignin
binder. Black and white liquors involved in this cooking process are corrosive
materials that attack the internal walls of the digester. The bleaching and
digesting processes involve chlorine & chlorine-based materials, hydrogen
sulfide, sulfur and sulfur dioxide. Hastelloy C276 is suitable for digester
materials and bleaching vessels due to its high resistance to corrosion in
various chloride-bearing environments, both alkaline and acidic.
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