Seamless Hastelloy C22 tube
Distinguished by its optimized chemistry, Hastelloy C22 provides superior resistance to pitting, crevice corrosion, and stress corrosion cracking (SCC), outperforming Alloy C276 in oxidizing environments containing wet chlorine and nitric acid. These tubes are indispensable for mission-critical applications in chemical reactors, pharmaceutical synthesizers, and flue gas desulfurization (FGD) systems. Through advanced cold-drawing and precise vacuum annealing, GZH ensures every tube maintains a uniform microstructure and maximum structural reliability under aggressive industrial conditions.
C22 PREN ≈ 45+
What Is a Seamless Hastelloy C22 Tube?
Hastelloy C22 tube is a high-performance, corrosion-resistant tube crafted from a single, solid billet of a nickel-chromium-molybdenum-tungsten superalloy. It is manufactured without a weld joint, ensuring superior structural integrity and reliability, especially under high-stress, high-temperature, and extremely corrosive conditions. The"Hastelloy C22"designation refers to a specific grade known for its exceptional resistance to both oxidizing and reducing acids, as well as to localized corrosion such as pitting and crevice corrosion. This alloy's unique composition makes it a top choice for applications in the most aggressive chemical processing and pollution control environments.
Key Features and Advantages
Seamless Hastelloy tube offer a unique combination of benefits that make them invaluable in the most demanding industries:
Universal Corrosion Resistance: Provides outstanding resistance to a wide range of corrosive media, including both oxidizing and reducing environments.
High Resistance to Pitting and Crevice Corrosion: The high chromium and molybdenum content provides excellent resistance to localized corrosion in chloride-containing environments.
High Pressure and Temperature Tolerance: The seamless construction and robust material allow the tube to safely handle high internal pressures and extreme temperatures.
Superior Weldability: The alloy can be welded using standard methods without the risk of post-weld corrosion, a key advantage for complex fabrications.
Resistance to Stress-Corrosion Cracking: The high nickel content makes the alloy highly resistant to chloride-ion stress-corrosion cracking.
Product Specifications and Data
To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for Hastelloy C22.
Table 1: Chemical Composition of Hastelloy C22
The composition of Hastelloy C22 is carefully balanced to achieve its superior corrosion resistance and high strength.
| Ni | Cr | Mo | W | C | Si | Co | Mn | V | P | S |
| Bal | 20.00-22.50 | 12.50-14.50 | 2.50-3.50 | ≤0.015 | ≤0.080 | ≤2.50 | ≤0.50 | ≤0.35 | ≤0.02 | ≤0.02 |
Table 2: Typical Mechanical Properties of Hastelloy C22
Hastelloy C22 is specifically designed to maintain its strength and shape in high-stress, corrosive environments.
| Property | Value (Annealed) |
| Tensile Strength | ≥ 690 MPa |
| Yield Strength | ≥ 283 MPa |
| Elongation | ≥ 45% |
| Hardness | ≤ 100 HRB |
Table 3: Typical Physical Properties of Hastelloy C22
These physical properties highlight the material's ability to perform reliably under a wide range of conditions.
| Property | Value |
| Density | 8.69 g/cm³ |
| Melting Point | 1399 °C approx. |
| Thermal Expansion | 12.4 µm/m·°C (20-100°C) |
| Thermal Conductivity | 11.1 W/m·K (20°C) |
| Modulus of Elasticity | 205 GPa |
| Electrical Resistivity | 1.15 x 10⁻⁶ Ω·m (20°C) |
Common Applications
The combination of high corrosion resistance and high strength of seamless Hastelloy C22 tubes makes them a preferred choice for:
Chemical Processing: Used in reactors, heat exchangers, and piping for handling aggressive chemicals like sulfuric acid, hydrochloric acid, and nitric acid.
Pollution Control: In scrubbers and stack liners for flue-gas desulfurization (FGD) systems.
Pharmaceuticals: In the production of pharmaceutical goods where high purity and corrosion resistance are critical.
Waste Treatment: In equipment for processing hazardous and corrosive waste.
Manufacturing Process
The manufacturing of a Seamless Hastelloy tube is a precise, multi-step process:
- Heating: A solid billet of Hastelloy C22 is heated to a high temperature.
- Hot extrusion: Hot extrusion is a metal forming process that shapes a metal billet by forcing it through a die at a temperature above its recrystallization temperature. This process softens the material, allowing for the creation of complex cross-sectional profiles with reduced force compared to cold extrusion, and it is commonly used to manufacture products like bars, tubes, and other special shapes from metals like aluminum, copper, and steel.
- Drawing and Sizing: The hollow shell is then rolled and drawn to reduce its diameter and wall thickness to the desired dimensions.
- Heat Treatment: The tube is solution annealed to achieve its specified metallurgical properties and to ensure optimal performance and corrosion resistance.
- Finishing: The tube is cut to length, straightened, and subjected to rigorous non-destructive testing to verify its integrity before final inspection and packaging. This meticulous process ensures that every seamless Hastelloy C22 tube is built to withstand the most demanding applications.
