NC2293 Alloy C22 (Hastelloy C22) bar steel

Description of Alloy C22 Bar

Alloy C22 is a Ni-Cr-Mo alloy containing tungsten (W) and extremely low levels of carbon and silicon. The high chromium content provides effective resistance to oxidising media, while the molybdenum and tungsten levels contribute to its durability in reducing environments. This nickel-based alloy resists oxidising aqueous media, including wet chlorine and mixtures containing nitric acid or oxidising acids with chloride ions. It also withstands exposure to oxidising acidic chlorides, wet chlorine, formic and acetic acids, iron and copper chlorides, seawater, brine and many mixed or contaminated chemical solutions, both organic and inorganic. In environments where reducing and oxidising conditions occur concurrently in process streams, the alloy maintains its performance; this is particularly important in multi-purpose facilities where such conditions are common.

This nickel-based alloy resists the formation of grain boundary precipitates in the heat-affected zone of welds and is, therefore, considered suitable for most chemical process applications in the welded state.

Alloy C22 should not be used at operating temperatures exceeding 1250° F, as harmful phases develop above this temperature.

Specifications for Alloy C22 Bar

ASTM Specifications

Applications of Alloy C22 Bar

• Stack Claddings:
• The alloy’s resistance to corrosion in both oxidising and reducing environments supports its sustained performance in stack cladding applications.
• Pipes:
• Due to its resistance to oxidation and corrosion in various aggressive media, the alloy maintains channel integrity over extended periods.
• Dampers:
• Its resistance to corrosion and oxidation ensures consistent performance of dampers in environments with potentially corrosive gases.
• Washers:
• The alloy withstands the corrosive effects of contaminants and chemicals in washers, as confirmed by quantitative data.
• Heat Exchangers:
• Resistance to both oxidising and reducing environments and stable thermal properties maintain the operational efficiency of heat exchangers.
• Reaction Vessels:
• The alloy’s resistance to various corrosive substances, including acids and chlorides, supports the structural integrity of reaction vessels.
• Evaporators:
• Its corrosion resistance is critical for evaporators operating in environments with concentrated solutions and corrosive substances, thereby ensuring reliability over time.