UNS N07718|2.4668|Inconel 718 Seamless Tube
Distinguished by its precipitation-hardening capabilities, our Inconel 718 tubing offers exceptional yield strength and resistance to creep-rupture at temperatures up to 700°C (1300°F). This makes them indispensable for mission-critical applications in aerospace engine components, high-strength cryogenic vessels, and downhole oil & gas tools. Through advanced cold-drawing and precise vacuum heat treatment, XinZhe ensures every tube maintains optimal microstructure and superior resistance to post-weld cracking and corrosion in aggressive media.
High-Performance Seamless Inconel 718 (UNS N07718) Tube | ASTM B829 Nickel Alloy Pipe
What is a Seamless Inconel 718 Tube?
A Seamless Inconel 718 tube (UNS N07718) is a high-performance nickel-chromium-iron superalloy pipe manufactured from a solid billet without any welding seams.
Compared to welded tubes, seamless Inconel 718 tubing offers:
- Superior structural integrity
- Enhanced pressure resistance
- Zero weld-related failure risk
This makes it ideal for high-temperature, high-pressure, and corrosive environments.
Inconel 718 is a precipitation-hardened nickel alloy known for its excellent tensile strength, creep resistance, and rupture strength at temperatures up to 1300°F (704°C).
Key Advantages of Inconel 718 Seamless Tubes
1. High-Temperature Strength
Maintains excellent mechanical properties from cryogenic temperatures to 704°C (1300°F), making it suitable for extreme thermal environments.
2. Superior Corrosion Resistance
- Resistant to oxidation and scaling
- Excellent resistance to stress corrosion cracking (SCC)
- Performs reliably in acidic and H₂S (sour gas) environments
3. High Pressure Capability
Manufactured in accordance with ASTM B829, enabling higher allowable pressure ratings for oil & gas and hydraulic systems.
4. Excellent Fatigue Resistance
Ideal for applications involving cyclic loads, vibration, and dynamic stress.
Product Specifications and Data
To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for Inconel 718.
The composition of Inconel 718 is carefully balanced to achieve its superior high-temperature strength and corrosion resistance.
Chemical Composition of Inconel 718
| Grade | Ni | Cr | Fe | Mn | Nb | Mo | Ti | C | Si | S | P | Co | B |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High | 50.0- 55.0 | 17.00-21.00 | Bal | ≤0.35 | 4.75- 5.50 | 2.80- 3.30 | 0.65- 1.15 | ≤0.08 | ≤0.35 | ≤0.015 | ≤0.015 | ≤1.0 | ≤0.006 |
Inconel 718 is specifically designed to maintain its strength and shape in high-stress, high-temperature environments.
Typical Mechanical Properties of Inconel 718
| Tensile Strength | Yield Strength | Elongation | Hardness |
|---|---|---|---|
| ≥ 1240 MPa | ≥ 1034 MPa | ≥20% | ≤40 HRC |
These physical properties highlight the material's ability to perform reliably under a wide range of conditions.
Typical Physical Properties of Inconel 718
| Density | Melting Point | Thermal Expansion | Thermal Conductivity | Modulus of Elasticity | Electrical Resistivity |
|---|---|---|---|---|---|
| 8.22 g/cm³ | 1260 - 1336 °C | 13.0 µm/m·°C (20-100°C) | 11.4 W/m·K (20°C) | 200 GPa | 1.2 x 10⁻⁶ Ω·m (20°C) |
| Nominal Outside Diameter, in. (mm) | Outside Diameter in. (mm) | Thickness of Specified Nominal Wall , % | Thickness of Specified Minimum Wall , % | |||
|---|---|---|---|---|---|---|
| Plus | Minus | Plus | Minus | Plus | Minus | |
| Over 0.400 (10) to 5/8 (16), excl | 0.005 (0.13) | 0.005 (0.13) | 15 | 15 | 30 | 0 |
| 5/8 (16) to 1 1/2 (38), incl | 0.0075 (0.19) | 0.0075 (0.19) | 10 | 10 | 22 | 0 |
| Over 1 1/2 (38) to 3 (76), incl | 0.010 (0.25) | 0.010 (0.25) | 10 | 10 | 22 | 0 |
| Over 3 (76) to 4 1/2 (114), incl | 0.015 (0.38) | 0.015 (0.38) | 10 | 10 | 22 | 0 |
| Over 4 1/2 (114) to 6 (152), incl | 0.020 (0.51) | 0.020 (0.51) | 12.5 | 12.5 | 28 | 0 |
| Over 6 (152) to 6 5/8 (168), incl | 0.025 (0.64) | 0.025 (0.64) | 12.5 | 12.5 | 28 | 0 |
| Over 6 5/8 (168) to 8 5/8 (219), incl | 0.031 (0.79) | 0.031 (0.79) | 12.5 | 12.5 | 28 | 0 |
Applications of Inconel 718 Seamless Tubing
Aerospace Industry
- Jet engine components
- Rocket motors
- High-temperature fasteners
Oil & Gas (HPHT Applications)
- Downhole tubing
- Wellhead components
- Subsea valves
Power Generation
- Gas turbines
- Nuclear reactor systems
Cryogenic Systems
- LNG storage
- Low-temperature piping
Manufacturing Process of Seamless Inconel 718 Tubes
1. Billet Preparation
High-purity Inconel 718 billets are heated to optimal forging temperatures.
2. Hot Extrusion
Formation of hollow mother tubes with uniform grain structure.
3. Cold Drawing / Pilgering
Precision control of outer diameter (OD) and wall thickness (WT).
4. Heat Treatment
Solution annealing followed by age hardening to form strengthening γ″ phase.
5. Quality Inspection
- 100% Eddy Current Testing (ECT)
- Ultrasonic Testing (UT)
- Hydrostatic Testing
Why Choose Our Inconel 718 Seamless Pipes?
- Manufactured according to ASTM B829 / ASME standards
- Suitable for marine, offshore, and aerospace applications
- Available with third-party inspection (e.g., ABS, PED)
- Full traceability and high-performance reliability
Ready to Request a Quotation?
Send us your specification for High seamless tube — OD, wall thickness, standard and quantity — and our engineering team will reply with a quotation within 24 hours.
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