Hastelloy C22 Fasteners: Strength and Resistance in One Alloy

When industries deal with highly aggressive chemicals and harsh working conditions, the choice of fasteners becomes critical. Standard stainless steels often fall short, leading to premature failures, costly downtime, and safety risks. The solution is Hastelloy C22 fasteners, engineered to perform under the most corrosive and demanding environments.

These fasteners, crafted from nickel-chromium-molybdenum alloy C22, have set a benchmark in industries like chemical processing, marine, pharmaceuticals, and pollution control systems. Known for their exceptional corrosion resistance, Hastelloy C22 fasteners combine long service life with high mechanical strength.

This blog provides a comprehensive guide to Hastelloy C22 fasteners, from their composition and properties to applications, advantages, and comparison with other alloys.

What Makes Hastelloy C22 Fasteners Special?

Hastelloy C22 fasteners are manufactured from UNS N06022 alloy, which is famous for handling both oxidizing and reducing chemicals. Unlike conventional fasteners, they resist pitting, crevice corrosion, and stress corrosion cracking, especially in chloride-rich conditions.

In industries where equipment failure is not an option, Hastelloy C22 fasteners offer consistent performance, safety, and reliability.

Composition of Hastelloy C22 Alloy

The key to the performance of Hastelloy C22 fasteners lies in its carefully engineered chemistry:

• Nickel (Ni): Balance

• Chromium (Cr): 20–22.5%

• Molybdenum (Mo): 12.5–14.5%

• Tungsten (W): 2.5–3.5%

• Iron (Fe): Up to 6%

• Cobalt (Co): Up to 2.5%

• Trace elements such as carbon, manganese, and silicon

This composition provides broad-spectrum resistance against strong oxidizers like nitric acid and reducing agents like hydrochloric acid.

Mechanical Strength of Hastelloy C22 Fasteners

• Tensile Strength: ~690 MPa

• Yield Strength: ~310 MPa

• Elongation: 40% minimum

• Hardness: ~90 HRB

These values make the fasteners not only corrosion-resistant but also mechanically robust for high-pressure and high-stress conditions.

Characteristics of Hastelloy C22 Fasteners

1. High Corrosion Resistance – Withstands oxidizing agents, reducing acids, and chloride attacks.

2. Excellent Thermal Stability – Retains strength at elevated temperatures.

3. Resistance to Localized Corrosion – Protects against pitting and crevice corrosion in marine and chemical environments.

4. Versatility in Fabrication – Can be machined, welded, and formed with ease.

5. Longevity and Reliability – Provides long-term service life, reducing maintenance needs.

Types of Hastelloy C22 Fasteners

🔹 Hastelloy C22 Bolts

Essential in pipelines, pressure vessels, and reactors where vibration resistance is required.

🔹 Hastelloy C22 Nuts

Provide a secure hold, especially in high-temperature and high-pressure environments.

🔹 Hastelloy C22 Washers

Used to distribute load evenly and prevent damage to surfaces.

🔹 Hastelloy C22 Screws

Ideal for chemical equipment requiring frequent maintenance and assembly.

🔹 Hastelloy C22 Studs & Threaded Rods

Preferred in desalination plants, offshore drilling rigs, and chemical reactors.

Applications of Hastelloy C22 Fasteners

Hastelloy C22 fasteners are used in multiple industries due to their resilience:

• Chemical Processing: Heat exchangers, reactors, evaporators, and piping systems.

• Marine Industry: Ships, offshore platforms, and desalination units exposed to seawater.

• Pharmaceuticals: Hygienic fastening solutions for sensitive processes.

• Pollution Control Systems: Scrubbers, stack liners, and flue gas desulfurization systems.

• Food and Beverage Industry: Equipment exposed to organic and inorganic chemicals.

• Pulp and Paper Industry: Resistant to bleaching chemicals such as chlorine dioxide.

Advantages of Hastelloy C22 Fasteners

✔ Unmatched corrosion resistance in oxidizing and reducing conditions.
✔ Protection against chloride-induced stress corrosion cracking.
✔ Durable and long-lasting, even in the harshest environments.
✔ Suitable for a wide range of industries, from chemicals to pharmaceuticals.
✔ Reduced downtime and maintenance costs, ensuring better productivity.

Hastelloy C22 Fasteners vs Other Fasteners

Industrial Standards

Hastelloy C22 fasteners are produced in accordance with global specifications such as:

• ASTM B574 – Bars and Rods

• ASTM B622 / B619 – Seamless and Welded Pipe standards (for material reference)

• ASME, DIN, ISO – For fastener dimensions and quality compliance

These ensure that Hastelloy C22 fasteners meet strict quality and safety requirements.

Maintenance and Care

While Hastelloy C22 fasteners are highly durable, some precautions maximize their life:

• Store in clean, dry environments to prevent contamination.

• Avoid mixing with carbon steel fasteners to reduce galvanic corrosion.

• Apply proper torque levels during installation.

• Inspect periodically in extreme chemical exposure.

Why Choose Hastelloy C22 Fasteners?

For industries that work in extreme corrosive and oxidizing conditions, choosing Hastelloy C22 fasteners means long-term reliability and safety. They may cost more than traditional options, but their ability to reduce downtime, avoid failures, and provide superior strength makes them a cost-effective choice over time.

Conclusion

Hastelloy C22 fasteners are not ordinary fastening solutions—they are engineered for industries that cannot compromise on safety, durability, and performance. Whether it’s Hastelloy C22 bolts, nuts, screws, washers, studs, or threaded rods, these components provide the strength and resistance needed in the most aggressive environments.

From chemical processing plants to marine engineering and pharmaceutical equipment, these fasteners have proven to be the gold standard. Their higher upfront cost is balanced by long service life, minimal maintenance, and unmatched reliability.

If your industry demands a fastener solution that performs where others fail, Hastelloy C22 fasteners are the answer.