In core components of aircraft engine fuel systems or nuclear reactor heat exchangers, the slightest error is unacceptable. For engineers and purchasing managers, the biggest pain points when sourcing GH4169 seamless steel tubing are:
Inconsistent wall thickness: Uneven wall thickness leads to localized stress concentration, causing the tubing to burst under high-pressure cycling.
Hidden internal cracks: Even in "commercial-grade" tubing, internal micropores and inclusions can lead to catastrophic fatigue failure.
Substitution risks: Unstable metallurgical processes that do not meet stringent AMS 5589 or ASTM B670 standards.
At Gnee Steel, we eliminate these risks. As a professional manufacturer, Gnee Steel offers aerospace-grade GH4169 steel tubing designed specifically for achieving ultimate structural integrity.
Check Our GH4169 Tube Stock & Wholesale Pricing
GH4169 (Inconel 718) High-Pressure Aerospace Tubing Manufacturer
GH4169 (Inconel 718) High-Pressure Aerospace Tubing Manufacturer
GH4169 (equivalent to Inconel 718) is a high-strength, precipitation-hardening nickel-chromium-iron superalloy designed for high-pressure, high-temperature aerospace piping and components. Due to its excellent fatigue resistance, creep resistance, and oxidation resistance at temperatures up to 700°C (1300°F), it is commonly used in rocket propellant delivery, jet engine piping, and hydraulic systems.
What is the melting point of INCONEL 718?
The melting point range of Inconel 718 is 1260-1340°C (2300-2440°F).
GH4169 (Inconel 718) High-Pressure Aerospace Tubing Chemical Composition Table (wt%)
| Element | Content (%) | Standard Requirement | Notes |
|---|---|---|---|
| Nickel (Ni) | 50.0 – 55.0 | 50.0 – 55.0 | Matrix element; provides high-temperature stability and corrosion resistance |
| Chromium (Cr) | 17.0 – 21.0 | 17.0 – 21.0 | Provides oxidation and corrosion resistance |
| Iron (Fe) | Balance (~18-20) | Balance | Matrix element; GH4169 is an Fe-Ni-Cr based alloy |
| Niobium (Nb) | 4.75 – 5.50 | 4.75 – 5.50 | Core strengthening element; forms γ″ phase (Ni₃Nb) |
| Molybdenum (Mo) | 2.80 – 3.30 | 2.80 – 3.30 | Solid-solution strengthening; improves high-temperature strength and pitting resistance |
| Titanium (Ti) | 0.65 – 1.15 | 0.65 – 1.15 | Forms γ′ strengthening phase (Ni₃(Al,Ti)) |
| Aluminum (Al) | 0.20 – 0.80 | 0.20 – 0.80 | Forms γ′ strengthening phase; promotes age hardening |
| Cobalt (Co) | ≤ 1.00 | ≤ 1.00 | Residual element; not intentionally added |
| Carbon (C) | ≤ 0.08 | ≤ 0.08 | Low carbon content; ensures good weldability and intergranular corrosion resistance |
| Manganese (Mn) | ≤ 0.35 | ≤ 0.35 | Deoxidizer |
| Silicon (Si) | ≤ 0.35 | ≤ 0.35 | Deoxidizer |
| Phosphorus (P) | ≤ 0.015 | ≤ 0.015 | Strictly controlled; ensures toughness and fatigue resistance |
| Sulfur (S) | ≤ 0.015 | ≤ 0.015 | Strictly controlled; ensures hot workability and creep resistance |
| Boron (B) | ≤ 0.006 | ≤ 0.006 | Trace grain boundary strengthener; improves stress rupture strength |
| Copper (Cu) | ≤ 0.30 | ≤ 0.30 | Residual element |
| Tantalum (Ta) | ≤ 0.05 | ≤ 0.05 | Residual element; typically counted with niobium |
Mechanical properties of GH4169 high-pressure tube under different temperature conditions (complete aging).
| Temperature (℃/°F) | Yield Strength (0.2% MPa) | Tensile Strength (MPa) | Elongation (%) |
| 20°C (Room) | ≥ 1030 | ≥ 1240 | ≥ 12 |
| 650°C (1200°F) | ≥ 850 | ≥ 1000 | ≥ 15 |
Click to download the GH4169 alloy PDF file now
1. GH4169 Pipe Material Standards and Names
Common Names: GH4169 (China), Inconel 718, Nickel Alloy 718, UNS N07718, W.Nr. 2.4668.
GH4169 Standard Applicable to Aviation Pipelines
| Standard | Description |
|---|---|
| AMS 5589 | Inconel 718 seamless tube (aviation grade) |
| AMS 5590 | Inconel 718 thin-wall tube (aviation grade) |
| ASTM B705 | Nickel alloy (UNS N07718) welded tube |
| GB/T 14994 | Superalloy cold-drawn tube (Chinese standard) |
| Q/S 10-0402 | Aviation GH4169 tube special technical specification |
2. Advantages of GH4169 Seamless Steel Pipe with VIM + VAR
The quality of seamless steel pipe depends on the purity of the steel ingot. Our GH4169 (equivalent to 718 alloy) is produced using a dual vacuum melting process:
VIM (Vacuum Induction Melting): Removes dissolved gases and volatile impurities.
VAR (Vacuum Arc Remelting): Removes inclusions, ensuring a uniform microstructure without segregation (no "freckles").
Final result: High-purity material with excellent industrial durability and fatigue resistance, capable of withstanding the most demanding high-temperature environments.
VIM + VAR process
3. GH4169 pipe supply types and technical specifications
We have a large stock of standard-sized GH4169 pipes for wholesale, and can also provide custom processing services for non-standard needs.
| Product Type | Outer Diameter (OD) | Wall Thickness (WT) | Standard Compliance |
| Seamless Tube | 6.0 mm - 219.0 mm | 0.5 mm - 25.0 mm | AMS 5589, ASTM B670 |
| Precision Tubing | 3.0 mm - 50.0 mm | 0.2 mm - 5.0 mm | h8-h11 Tolerance |
| Instrumentation Pipe | 1/16" - 1" NPS | Sch 10, Sch 40, Sch 80 | ASME SB670 |
4. Typical applications of GH4169 aviation pipelines
| Application Area | Specific Components |
|---|---|
| Aircraft Engines | High-pressure hydraulic lines, fuel manifold tubes, bleed air ducts |
| Space Systems | Rocket engine fuel delivery tubes, high-pressure gas lines |
| Aerospace Structures | Landing gear actuation tubing, brake system high-pressure lines |
Why choose Gnee Steel?
✅️Direct Factory Pricing: By cutting out the middleman, we save you 15-20% on your procurement costs for Tier-1 Supplier quality.
✅️MTC 3.1 Traceability: Every order is accompanied by an EN 10204 3.1 Mill Test Certificate documenting heat analysis and mechanical verification.
✅️100% NDT Inspection: Our pipes undergo 100% Ultrasonic (UT) and Eddy Current (ET) testing to ensure zero internal or surface defects.
✅️Global Logistics Support: Fast shipping to USA, Europe, and Asia with specialized export-grade seaworthy packaging.
Contact us now to get the latest export price for GH4169 in 2026
FAQ
Q1: Is GH4169 tubing equivalent to Inconel 718?
A: Yes. GH4169 is the designation used in Chinese national standards (GB/T 14992). It is chemically and mechanically identical to Inconel 718 (UNS N07718) and is globally interchangeable.
Q2: Can your tubes handle high-pressure hydraulic cycles at 600°C?
A: Absolutely. Our GH4169 tubes are designed specifically for high-pressure service. The precipitation-hardening phase remains stable up to 700°C, providing the highest yield strength in its class.
Q3: Do you offer centerless grinding for precision OD tolerances?
A: Yes. For applications requiring a perfect fit (like sensor housings or fuel connectors), we provide precision-ground tubes with h9 or h10 tolerances.
Q4: Do you offer bulk discounts for major energy infrastructure projects?
A: Yes. As a Reliable Supplier, we support large-scale projects with tiered Wholesale Pricing and dedicated project management.
