Incoloy 800 / 800H / 800HT Pipe Fittings
Incoloy 800 / 800H / 800HT Pipe Fittings Manufacturer & Supplier
Incoloy 800, 800H, and 800HT Pipe Fittings are high-performance nickel-iron-chromium alloys engineered for exceptional strength, oxidation resistance, carburization resistance, and thermal stability at elevated temperatures. These fittings are widely used in petrochemical plants, heat exchangers, refineries, power generation, and high-temperature service environments.
The differences between the grades lie mainly in their carbon content and annealing treatment, giving each grade enhanced performance at different temperature ranges:
Incoloy 800 – General high-temperature corrosion resistance
Incoloy 800H – Higher carbon for improved creep strength
Incoloy 800HT – Controlled carbon & aluminum/titanium for enhanced stability
These pipe fittings offer excellent fabricability, weldability, and long-term structural integrity under extreme conditions.
Key Features
Excellent strength at high temperatures up to 1100°C (2000°F)
Superior resistance to oxidation, carburization & nitriding
High resistance to sulfur-containing atmospheres
Good creep and stress-rupture strength
Outstanding resistance to chloride stress corrosion cracking
Excellent thermal stability and metallurgical structure
Good weldability using standard welding methods
Suitable for high-pressure & high-temperature piping systems
Specifications
| Standard | Details |
|---|---|
| Grades | Incoloy 800, 800H, 800HT |
| Specifications | ASTM B366, ASME SB366 |
| Type | Seamless / Welded / Buttweld / Forged |
| Fitting Types | Elbow, Tee, Reducer, Cap, Stub End, Cross, Nipple |
| Size Range | ½” to 48” |
| Schedule | SCH 10s, 20, 40, 60, 80, 120, 160, XXH |
| Dimensions | ASME B16.9, ASME B16.28, MSS SP-43 |
| Form | Long Radius, Short Radius |
| End Connections | Buttweld, Socket Weld, Threaded |
| Manufacturing Method | Hot Formed / Cold Formed / Fabricated |
Equivalent Grades
| Alloy | UNS | Werkstoff Nr. |
|---|---|---|
| Incoloy 800 | N08800 | 1.4876 |
| Incoloy 800H | N08810 | 1.4958 |
| Incoloy 800HT | N08811 | 1.4959 |
Available Sizes
Pipe Fittings Size: ½” to 48”
Thickness: SCH 10–XXH
Custom sizes available upon request
Chemical Composition
| Element | 800 (%) | 800H (%) | 800HT (%) |
|---|---|---|---|
| Nickel (Ni) | 30–35 | 30–35 | 30–35 |
| Chromium (Cr) | 19–23 | 19–23 | 19–23 |
| Iron (Fe) | Balance | Balance | Balance |
| Carbon (C) | ≤ 0.10 | 0.05–0.10 | 0.06–0.10 |
| Aluminum (Al) | 0.15–0.60 | 0.15–0.60 | 0.25–0.60 |
| Titanium (Ti) | 0.15–0.60 | 0.15–0.60 | 0.25–0.60 |
| Manganese (Mn) | ≤ 1.5 | ≤ 1.5 | ≤ 1.5 |
| Silicon (Si) | ≤ 1.0 | ≤ 1.0 | ≤ 1.0 |
Mechanical Properties
| Property | 800 | 800H | 800HT |
|---|---|---|---|
| Tensile Strength | 520 MPa | 520 MPa | 520 MPa |
| Yield Strength | 205 MPa | 205 MPa | 205 MPa |
| Elongation | 30% | 30% | 30% |
| Hardness | 85 HRB | 85 HRB | 85 HRB |
Physical Properties
| Property | Value |
|---|---|
| Density | 7.94 g/cm³ |
| Melting Range | 1350–1400°C |
| Thermal Conductivity | 14.8 W/m·K |
| Electrical Resistivity | 1.03 µΩ·m |
| Specific Heat | 460 J/kg·K |
Types of Incoloy 800 / 800H / 800HT Pipe Fittings
Long Radius & Short Radius Elbow
Equal & Reducing Tee
Concentric & Eccentric Reducer
End Cap
Stub End (Long / Short)
Cross Fitting
Pipe Nipple
Custom / Fabricated Fittings
Corrosion Resistance
Oxidation & scaling at elevated temperatures
Carburizing atmospheres common in petrochemical processes
Sulfur-containing environments
Chloride-induced stress corrosion cracking
High-temperature aqueous corrosion
Heat Resistance
Stable microstructure up to 1100°C
High resistance to thermal fatigue
Excellent creep and stress-rupture strength
Superior stability during long-term high-temperature service
Heat Treatment
Solution Annealing: 980°C to 1100°C
Cooling: Air cooled
800H and 800HT receive controlled annealing to yield optimal creep properties
Welding
Incoloy 800 series pipe fittings can be welded using:
TIG Welding
MIG Welding
SMAW / Stick Welding
Submerged Arc Welding
Filler metals such as Inconel 82/182 are recommended for superior metallurgical bonding.
Fabrication
Excellent hot and cold workability
Easily machinable with standard equipment
Requires slightly higher forming temperatures due to high strength
Maintains toughness after fabrication
Applications
Petrochemical Plants
Heat Exchangers
Hydrocarbon Processing
Furnace Equipment
Power Generation Boilers
Superheater & Reheater Tubes
Chemical Processing Units
Gas Turbine Components
Refineries
Industrial Heating Systems