Chemical Composition
| Element | Ni | Cr | Mo | Cu | Fe | ||
| % Range | 30–34 | 26–28 | 3–4 | 1–2.5 | Bal. | 12 | |
Mechanical Properties
- Tensile Strength: ≥620 MPa
- Yield Strength: ≥300 MPa
- Elongation: ≥40%
- Hardness: 150–200 HB (Annealed) 24
Key Performance Advantages
- Corrosion Resistance:
- Superior resistance to sulfuric acid, hydrochloric acid, phosphoric acid, and chloride stress corrosion cracking (SCC) 12.
- Excellent performance in mixed acid environments (e.g., nitric + hydrochloric acid)
- High-Temperature Stability: Maintains strength up to 550°C 25.
Types of Nuts Produced with Alloy 28
- Hex Nuts (ISO 4032 / DIN 934)
- Flange Nuts (ISO 7040)
- Lock Nuts (DIN 985)
- Heavy-Duty Coupling Nuts (ANSI B18.2.2)
- Custom threads: UNC, UNF, Metric 23
Applications Across Industries
- Chemical & Petrochemical:
- Reactors, heat exchangers, and pipelines for sulfuric acid, phosphoric acid, and chloride-rich environments 12.
- Oil & Gas:
- Offshore platform components, sour gas processing equipment, and deep-sea oil drilling systems 23.
- Marine Engineering:
- Seawater-cooled heat exchangers, desalination plants, and marine pipeline fasteners 23.
- Nuclear & Medical:
- Nuclear reactor components and medical devices requiring corrosion resistance and biocompatibility 24.
- Alloy 28 nuts
- UNS N08028 fasteners
- ASTM B668 hex nuts
- Corrosion-resistant alloy nuts
- DIN 1.4563 fasteners
- High-temperature Alloy 28 nuts
- Sulfuric acid-resistant fasteners
- Marine-grade Alloy 28 nuts
Why Choose Alloy 28 Nuts?
- Cost-Efficiency: Comparable performance to Hastelloy C-276 at a lower material cost 23.
- Weldability: Compatible with TIG, MIG, and plasma welding; post-weld heat treatment optional 45.
- “Alloy 28 Nuts for Offshore Platforms”).
- Explore Alloy 28 bolts for nuclear reactors”).
- Alloy 28 Hex Nuts in Chemical Reactor Assembly”.
