Alloy 718，Inconel 718 Fittings，UNS N07718，EFORU

British Specs:，American Specs: AMS 5662 Bar and Forgings AMS 5663 Bar and Forgings AMS 5664 Bar and Forgings AMS 5589 Seamless Tube AMS 5590 (Tube *) AMS 5596 Sheet, Strip and Plate AMS 5597 Sheet, Strip and Plate AMS 5832 Welding Wire AMS 5914 Sheet, Strip and Foil AMS 5950 (718SPF) Sheet & Strip ASTM F3055 Powder，German Specs:

### **Product Introduction: Alloy 718 / Inconel 718 Fittings (UNS N07718)** #### **Overview** **Alloy 718 Fittings** (commercially known as **Inconel® 718 Fittings**) are precision-engineered components designed for critical piping and tubing systems operating in extreme environments. These fittings leverage the exceptional properties of Alloy 718, including high strength retention at elevated temperatures, outstanding corrosion resistance, and excellent fatigue performance. Manufactured through forging, machining, and specialized forming processes, Inconel 718 fittings maintain structural integrity and leak-proof performance in temperatures ranging from cryogenic conditions to 700°C (1300°F), making them essential for aerospace, oil and gas, and chemical processing applications. The unique precipitation-hardening characteristics of Alloy 718, achieved through gamma double prime (γ'') phase [Ni₃Nb] formation, ensure that these fittings maintain their mechanical properties and dimensional stability even after prolonged exposure to aggressive service conditions. --- #### **Chemical Composition** The chemical composition of Alloy 718 Fittings (UNS N07718) conforms to strict international standards: | Element | Content (%) | | :--- | :--- | | **Nickel (Ni)** | 50.0 - 55.0 | | **Chromium (Cr)** | 17.0 - 21.0 | | **Iron (Fe)** | Balance | | **Niobium (Nb)** | 4.75 - 5.50 | | **Molybdenum (Mo)** | 2.80 - 3.30 | | **Titanium (Ti)** | 0.65 - 1.15 | | **Aluminum (Al)** | 0.20 - 0.80 | | **Cobalt (Co)** | ≤ 1.00 | | **Carbon (C)** | ≤ 0.08 | | **Manganese (Mn)** | ≤ 0.35 | | **Silicon (Si)** | ≤ 0.35 | | **Sulfur (S)** | ≤ 0.015 | | **Copper (Cu)** | ≤ 0.30 | | **Boron (B)** | ≤ 0.006 | *The carefully balanced composition enables optimal precipitation hardening through gamma double prime [γ'' Ni₃Nb] and gamma prime [γ' Ni₃(Al,Ti)] phases during heat treatment.* --- #### **Physical Properties** Critical properties for fitting design and system engineering: | Property | Metric Value | Imperial Value | | :--- | :--- | :--- | | **Density** | 8.19 g/cm³ | 0.296 lb/in³ | | **Melting Range** | 1260 - 1336 °C | 2300 - 2440 °F | | **Specific Heat (20°C)** | 435 J/kg·K | 0.104 Btu/lb·°F | | **Thermal Conductivity (20°C)** | 11.4 W/m·K | 79.1 Btu·in/hr·ft²·°F | | **Thermal Expansion Coefficient (20-100°C)** | 13.0 μm/m·°C | 7.2 μin/in·°F | | **Modulus of Elasticity** | 200 GPa | 29.0 x 10⁶ psi | | **Electrical Resistivity** | 1.25 μΩ·m | - | --- #### **Mechanical Properties** Mechanical properties are developed through specific heat treatment cycles: **Solution Annealed + Aged Condition:** * **Ultimate Tensile Strength:** ≥ 1275 MPa (185 ksi) * **Yield Strength (0.2% Offset):** ≥ 1035 MPa (150 ksi) * **Elongation:** ≥ 12% * **Reduction of Area:** ≥ 15% * **Hardness:** 35-45 HRC **Pressure Performance:** * **Maximum Working Pressure:** Varies with fitting design and size * **Temperature Rating:** Up to 700°C (1300°F) continuous service * **Burst Pressure:** Excellent resistance to pressure deformation --- #### **International Standards** Alloy 718 Fittings conform to numerous international specifications: **Dimensional Standards:** * **ASME B16.11:** Forged Fittings, Socket-Welding and Threaded * **MSS SP-79:** Socket-Welding Reducer Inserts * **MSS SP-97:** Integrally Reinforced Forged Branch Outlet Fittings **Material Standards:** * **ASTM B564:** Standard Specification for Nickel Alloy Forgings * **AMS 5662:** Nickel Alloy, Corrosion and Heat-Resistant, Bars, Forgings, and Rings * **ASTM B805:** Precipitation Hardening Nickel Alloy Bars, Forgings, and Forging Stock **Quality Standards:** * **ISO 9001:** Quality Management Systems * **ASME BPVC:** Boiler and Pressure Vessel Code * **NACE MR0175:** Sulfide Stress Cracking Resistance --- #### **Product Applications** Alloy 718 fittings serve critical functions across multiple high-performance industries: **Aerospace & Defense:** * **Aircraft Hydraulic Systems:** Fittings for high-pressure hydraulic lines * **Fuel Systems:** Connectors, unions, and adapters for fuel management * **Engine Systems:** Bleed air duct fittings, lubrication system components * **Spacecraft:** Propulsion system fittings, fuel line connectors **Oil & Gas Industry:** * **Downhole Tools:** Instrumentation fittings, control line connectors * **Subsea Systems:** Hydraulic fittings, chemical injection connectors * **Surface Equipment:** Wellhead fittings, Christmas tree components * **Processing Plants:** High-pressure pipeline fittings, valve connectors **Power Generation:** * **Nuclear Plants:** Primary circuit fittings, instrument connections * **Gas Turbines:** Fuel system fittings, hydraulic control connectors * **Steam Systems:** High-temperature steam line fittings **Industrial Processing:** * **Chemical Plants:** Corrosive fluid handling fittings * **Heat Treatment:** Furnace gas supply fittings, quenching system components * **Pharmaceutical:** High-purity process system fittings --- #### **Key Advantages** * **Exceptional Strength:** Maintains high mechanical properties at elevated temperatures * **Superior Corrosion Resistance:** Excellent resistance to pitting, crevice corrosion, and stress corrosion cracking * **Excellent Weldability:** Can be welded to similar and dissimilar materials using conventional methods * **Outstanding Fatigue Performance:** Superior resistance to vibration and pressure cycling * **Dimensional Stability:** Maintains precise tolerances under thermal cycling conditions * **Pressure Integrity:** Excellent resistance to internal and external pressure deformation * **Long Service Life:** Maintains performance in aggressive environments over extended periods * **Quality Consistency:** Uniform microstructure and mechanical properties throughout each fitting **Note:** *Inconel® is a registered trademark of Special Metals Corporation, a PCC company. Alloy 718 fittings are available in various types including elbows, tees, reducers, couplings, unions, and special configurations. They are typically supplied in solution annealed and aged condition to meet specific application requirements. Proper installation techniques and torque specifications must be followed to ensure optimal performance and system integrity.*

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 1788 gallon liquid totes Special package is available on request.