1. What are the chemical compositions of these nickel alloy pipes/tubes?
Answer:
Inconel 718 (UNS N07718): Ni 50–55%, Cr 17–21%, Nb + Ta 4.75–5.5%, Mo 2.8–3.3%, Fe 17%, minor Al and Ti. High-strength, precipitation-hardened alloy.
Inconel 625 (UNS N06625): Ni 58–63%, Cr 20–23%, Mo 8–10%, Nb + Ta 3.15–4.15%, Fe ≤5%. Excellent corrosion and oxidation resistance.
Inconel X-750 (UNS N07750): Ni 71%, Cr 14–17%, Fe 7%, Al + Ti 1.2–2%, strengthened by precipitation hardening.
Inconel 825 (UNS N08825): Ni 38–46%, Fe 21.5–25%, Cr 19.5–23.5%, Mo 2.5–3.5%, Cu 1.5–3.0%. Resistant to acids and seawater corrosion.
2. What are the typical mechanical properties of these nickel alloy pipes/tubes?
Answer:
Inconel 718: Tensile 1240 MPa, Yield 1030 MPa, Elongation ≥12%
Inconel 625: Tensile 827 MPa, Yield 414 MPa, Elongation ≥30%
Inconel X-750: Tensile 1030 MPa, Yield 690 MPa, Elongation 12–20%
Inconel 825: Tensile 585 MPa, Yield 275 MPa, Elongation ≥30%
These properties make them suitable for high-temperature, high-stress, and corrosive environments.
3. What are the common applications of these nickel alloy pipes/tubes?
Answer:
Inconel 718: Aerospace engines, gas turbines, nuclear reactors, high-strength fasteners
Inconel 625: Chemical processing, marine environments, heat exchangers, offshore oil & gas
Inconel X-750: Turbine blades, springs, nuclear components, high-temperature fasteners
Inconel 825: Chemical and petrochemical plants, acid-resistant piping, marine equipment
4. What sizes and forms are available for these pipes/tubes?
Answer:
Outer diameter: 6 mm – 500 mm (varies by alloy and supplier)
Wall thickness: 1 mm – 50 mm (customizable)
Length: Standard 1–6 m, can be cut to requirement
Forms: Hot-rolled, cold-drawn, seamless, or welded tubes
Surface finish: Pickled, bright, or matte depending on customer needs
5. How is the quality of these nickel alloy pipes/tubes verified?
Answer:
Chemical composition verification: OES/XRF testing
Mechanical testing: Tensile, yield, elongation, hardness
Non-destructive testing: Ultrasonic, eddy current, hydrostatic pressure test
Dimensional inspection: Outer diameter, wall thickness, straightness
Certification: EN 10204 3.1/3.2 Mill Test Certificates, heat treatment and production records
