Alloy 800HT,Incoloy 800HT Tube,N08811,E FORU

British Specs:BS 3072 BS 3073 BS 3074 BS 3075 BS 3076 NA15，American Specs:AMS 5766 Bar and Forgings AMS 5871 Sheet, Strip and Plate ASTM B408 ASTM B564 ASTM A240 ASTM A480，German Specs:WS 1.4876 WS 1.4958 WS 1.4959

**Technical Datasheet: Alloy 800HT / Incoloy 800HT Tube (UNS N08811)** --- ### **1.0 Product Overview** **Alloy 800HT Tube** (commercially known as **Incoloy 800HT Tube**, UNS **N08811**) is a high-performance nickel-iron-chromium superalloy tubing product engineered for extreme temperature and pressure applications. With enhanced chemistry featuring controlled carbon content (0.06–0.10%) and elevated aluminum+titanium (Al + Ti ≥ 1.20%), this alloy delivers exceptional creep rupture strength, oxidation resistance, and structural stability at temperatures up to 815°C (1500°F). These tubes are specifically designed for the most demanding heat transfer and pressure containment applications across various industries. --- ### **2.0 Chemical Composition (wt%)** | Element | Content (ASTM B163/ASME SB-163) | Role | |---------|----------------------------------|------| | Ni | 30.0–35.0 | Austenitic matrix stability, oxidation/carburization resistance | | Cr | 19.0–23.0 | High-temperature oxidation and sulfidation resistance | | Fe | ≥39.5 | Base element | | C | 0.06–0.10 | Enhanced carbide strengthening for creep resistance | | Al | 0.25–0.60 | Forms stable protective oxide scale | | Ti | 0.25–0.60 | Stabilization and precipitation strengthening | | Mn | ≤1.50 | Improves hot workability | | Si | ≤1.00 | Enhances oxidation/carburization resistance | | S | ≤0.015 | Minimized to avoid hot shortness | | Cu | ≤0.75 | — | *Critical Requirement: Aluminum + Titanium ≥ 1.20% for UNS N08811* --- ### **3.0 Physical Properties** | Property | Value | Condition | |----------|-------|-----------| | Density | 8.03 g/cm³ (0.29 lb/in³) | RT | | Melting Range | 1354–1384°C (2470–2520°F) | — | | Specific Heat | 460 J/kg·K (0.11 Btu/lb·°F) | 21°C (70°F) | | Thermal Conductivity | 15.6 W/m·K (9.0 Btu·in/hr·ft²·°F) | 21°C (70°F) | | Thermal Expansion | 16.6 × 10⁻⁶ /K | 20–650°C | | Electrical Resistivity | 116 μΩ·cm (45.8 μΩ·in) | 21°C (70°F) | | Modulus of Elasticity | 201 GPa (29.1 × 10⁶ psi) | RT | | Magnetic Permeability | <1.05 | Essentially non-magnetic | --- ### **4.0 Mechanical Properties** **Room-Temperature Properties (Solution-Annealed Condition)** - **Tensile Strength:** 450 MPa min (65 ksi min) - **Yield Strength (0.2% Offset):** 170 MPa min (25 ksi min) - **Elongation:** 30% min (in 2 inches) - **Hardness:** 70–90 HRB **Elevated Temperature Performance** - **Max Service Temperature:** 815°C (1500°F) continuous - **Creep Strength:** Superior stress rupture properties at 650–815°C - **Pressure Rating:** ASME BPVC Section I and VIII compliance --- ### **5.0 International Standards** | Standard Type | Number | Description | |--------------|--------|-------------| | UNS | N08811 | Unified Numbering System | | ASTM | B163 | Seamless Condenser and Heat-Exchanger Tubes | | ASTM | B407 | Seamless Pipe and Tube | | ASTM | B829 | Nickel Alloy Seamless Pipe and Tube | | ASME | SB-163 | Boiler and Pressure Vessel Code | | EN/DIN | 1.4959 | X8NiCrAlTi32-21 (Enhanced) | | TEMA | Standards | Heat Exchanger Tube specifications | --- ### **6.0 Product Specifications** **Tube Types Available** - **Seamless Tubes:** OD 3–100 mm (0.125–4 inches) - **Welded Tubes:** OD 15–120 mm (0.625–4.75 inches) - **Heat Exchanger Tubes:** per TEMA standards - **Boiler Tubes:** per ASME Section I **Size Ranges & Tolerances** - **OD Tolerances:** ±0.1 mm for precision tubes - **Wall Thickness:** ±10% standard, ±5% precision available - **Length:** Up to 25 meters maximum - **Straightness:** 1.5 mm per meter maximum --- ### **7.0 Applications** **Heat Exchanger Applications** - Shell and tube heat exchangers - Waste heat recovery units - Feedwater heaters in power plants - Process gas coolers and heaters - Condenser and evaporator tubes **Petrochemical Industry** - Ethylene cracking furnace tubes - Steam methane reformer tubes - Pyrolysis furnace tubes - Reformer and cracker heat exchanger tubes **Power Generation** - Superheater and reheater tubes - Boiler tubes in conventional power plants - Nuclear steam generator tubes - Heat recovery steam generator tubes **Industrial Furnace Systems** - Radiant tubes in heat treatment furnaces - Muffle furnace tubes - Annealing furnace tubes - Carburizing and nitriding retorts --- ### **8.0 Fabrication Characteristics** **Welding & Joining** - **Recommended Processes:** GTAW, Laser, Orbital welding - **Filler Metal:** ERNiCrFe-8 for matching properties - **Preheat:** Not required for wall thickness < 12 mm - **Post-Weld Heat Treatment:** Solution anneal at 1120–1170°C for critical applications **Tube Expansion & Bending** - **Cold Bending:** Minimum bend radius 2× OD - **Tube Expansion:** Maximum 8% wall reduction - **U-Bend Formation:** Minimum bend radius 2× OD for seamless tubes **Installation Considerations** - **Tube Sheet Joints:** Rolling and welding techniques - **Support Spacing:** Per TEMA standards - **Thermal Expansion:** Adequate provision for thermal growth --- ### **9.0 Quality Assurance** **Testing & Certification** - Mill Test Certificate 3.1 per EN 10204 - Hydrostatic or pneumatic pressure testing - Eddy current or ultrasonic testing - Flare, flange, and crush tests as required **Dimensional Standards** - **OD & Wall Thickness:** per ASTM B163 - **Length Tolerances:** +3 mm, -0 mm for cut lengths - **Surface Finish:** 0.8 μm Ra internal, 1.6 μm Ra external available **Special Testing Available** - Grain size testing (ASTM 3–6 required) - Hardness testing multiple locations - High-temperature proof testing - Intergranular corrosion testing per ASTM A262 --- ### **10.0 Technical Specifications** **Heat Treatment** - **Solution Annealing:** 1120–1170°C (2050–2140°F) - **Cooling Method:** Rapid air or water quenching - **Annealing Atmosphere:** Bright annealing available **Surface Conditions** - **Pickled & Descaled:** Standard finish - **Bright Annealed:** Special order - **Polished:** ID and/or OD polishing available --- ### **11.0 Advantages** - **Enhanced Creep Resistance:** Superior to standard 800H at high temperatures - **Excellent Heat Transfer Properties:** Optimal thermal conductivity for heat exchanger applications - **Oxidation Resistance:** Superior performance in oxidizing atmospheres up to 1150°C - **Microstructural Stability:** Resists sigma phase formation and embrittlement - **Code Compliance:** Meets ASME, ASTM, and TEMA standards for critical applications --- ### **12.0 Storage & Handling** - Store in clean, dry conditions to prevent contamination - Protect tube ends with plastic caps during handling - Maintain proper identification and heat number traceability - Stack properly to prevent deformation and damage --- **Contact Information** For technical specifications, pricing, or custom tube requirements, please contact our technical sales team.

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 1914 gallon liquid totes Special package is available on request.