What temperature is Hastelloy C22?
|
Element |
Min |
Max |
|
Molybdenum |
12.5 |
14.5 |
|
Chromium |
20.0 |
22.5 |
|
Iron |
2.00 |
6.00 |
|
Tungsten |
2.50 |
3.50 |
|
Cobalt |
-- |
2.50 |
|
Carbon |
-- |
0.010 |
|
Silicon |
-- |
0.08 |
|
Manganese |
-- |
0.50 |
|
Vanadium |
-- |
0.35 |
|
Phosphorus |
-- |
0.025 |
|
Sulfur |
-- |
0.010 |
|
Nickel |
Remainder |
|
Corrosion Resistance in the As-Welded Condition
Hastelloy C-22 is a versatile nickel-chromium-molybdenum alloy that has an overall corrosion resistance superior to other nickel-chromium-molybdenum alloys available today, including Hastelloy C-276, C-4, and A625. Alloy C-22 has excellent resistance to pitting, crevice corrosion, and stress corrosion cracking. It has excellent resistance to oxidizing aqueous media, including acids containing oxidizers, wet chlorine, and mixtures of oxidizing acids containing nitric acid or chloride ions. Hastelloy C-22 has excellent resistance to both reducing and oxidizing media, and because of its versatility, can be used where "unusual" conditions may occur or in multi-purpose plants.
Hastelloy C-22 has excellent resistance to a wide range of chemical process environments, including strong oxidizers (such as ferric and cupric chlorides), thermally contaminated media (organic and inorganic), chlorine, formic and acetic acids, acetic anhydride, seawater, and brine solutions.
Hastelloy C-22 resists the formation of grain boundary precipitates in the weld heat affected zone, making it suitable for most chemical process applications in the as-welded condition.
Machinability
Hastelloy C-22 can be fabricated using the same techniques as alloys C-276 or C-4. It can be welded, forged, hot upset, and impact extruded. Alloy C-22 can also be successfully deep drawn, spun, press formed, or stamped, although the alloy is susceptible to work hardening.
Parts that have been hot formed or severely cold formed should be heat treated at 2050 °F and rapidly quenched prior to final fabrication or installation.
Specifications
Hastelloy C-22 is subject to ASME specifications. Plate, sheet, strip, bar, tube, and pipe are subject to ASME specifications SB-574, SB-575, SB-619, SB-622, and SB-626 and ASTM specifications B-574, B-575, B-619, B-622, and B-626. The UNS number is NO6022.
Applications
Current or potential applications for C-22 alloy include: acetic acid/acetic anhydride, cellophane manufacturing, chlorine gas injectors, chlorination systems, circuit board etching equipment, complex acid/chemical mixtures, fans and blowers, galvanizing line equipment, gas scrubber systems, geothermal wells, high frequency furnaces, incineration systems, nuclear fuel reprocessing, pesticide production, phosphoric acid applications, pickling system components, plate heat exchangers, selective leaching systems, oxysulfide cooling towers, sulfonation systems, and tubular heat exchangers.
