ASTM B163 Incoloy 825 for chemical processing industry pipes

 

 

ASTM B163 Incoloy 825 for chemical processing industry pipes

01.

ASTM B163 Incoloy 825 for chemical processing industry pipes

For the chemical processing industry, ASTM B163 Incoloy 825 is a key material for piping due to its excellent resistance to a wide range of corrosive and high-temperature environments. This nickel-based alloy, designated UNS N08825, is commonly used in applications such as heat exchangers and condensers.

02.

What are the specifications of Incoloy 825?

Incoloy 825 Properties
Density 8.14 g/cm³, 0.294 lbs/in³, tensile strength at least 586 MPa (85 Ksi), yield strength at least 241 MPa (35 Ksi). It offers excellent resistance to reducing and oxidizing acids, stress corrosion cracking, and localized corrosion such as pitting and crevice corrosion.

Chemical Composition of Incoloy Alloy 825 pipes

Tensile Properties of Incoloy Alloy 825 pipes

ASTM B163 and its application to Incoloy 825
The ASTM B163 standard specifically covers seamless nickel and nickel alloy tubing for use in heat exchangers and condensers. For Incoloy 825, this means that pipe produced in accordance with ASTM B163 will be:
Seamless, without welds.
Primarily used in heat transfer applications.
For outside diameters of 3 inches (76.2 mm) or smaller.
Tested to verify chemical composition, mechanical properties, and dimensions.
Supplied in the hot-finished or cold-finished annealed condition.

Performance Limitations
Although Incoloy 825 is extremely strong, its temperature limitations must be observed in chemical processing applications:
The maximum service temperature is generally limited to approximately 1,000°F (538°C).
Exceeding this temperature limit can cause detrimental microstructural changes that significantly reduce the alloy's ductility and impact strength.
It is not recommended for applications where creep rupture performance is a design factor.

Fabrication and Joining
For chemical processors, understanding how to use this material is crucial:
Weldability: Incoloy 825 welds easily using standard processes such as gas metal arc welding (MIG), gas tungsten arc welding (TIG), and manual stick arc welding (SMAW).
Post-weld heat treatment: Due to the alloy's titanium content, post-weld heat treatment is generally not required to maintain its corrosion resistance.
Formability: The alloy can be hot- and cold-worked and exhibits good formability.