Hastelloy S Flanges
Hastelloy S Flanges ( UNS N06635 ) Manufacturer & Supplier
Hastelloy S Flanges are manufactured using a solid-solution-strengthened nickel-chromium-molybdenum-tungsten alloy developed specifically for excellent oxidation resistance at elevated temperatures. Known for maintaining exceptional strength, stability, and durability up to 1200°C, Hastelloy S is ideal for high-temperature industrial applications where oxidation and thermal cycling are major concerns.
These flanges provide superior performance in industrial furnaces, combustion systems, gas turbine components, and petrochemical reactors. They combine high-temperature strength with outstanding resistance to oxidizing environments, ensuring long operational life and reliability.
Key Features
Exceptional oxidation resistance up to 1200°C
High mechanical strength at elevated temperatures
Excellent resistance to carburization and thermal fatigue
Good structural stability in long-term high-temperature exposure
Outstanding weldability and formability
Designed for oxidizing environments such as flue gas systems
Ideal for demanding heat-treatment and furnace components
Specifications
| Specification | Details |
|---|---|
| Grade | Hastelloy S |
| UNS | N06635 |
| Werkstoff Nr. | 2.4610 |
| Standards | ASTM B564 / ASME SB564 |
| Flange Types | WNRF, SORF, BLRF, SWRF, Threaded, Lap Joint, Orifice, Long Weld Neck |
| Size Range | ½” to 48” |
| Pressure Class | 150#, 300#, 600#, 900#, 1500#, 2500# |
| Face Types | RF / RTJ / FF |
| Manufacturing | Forged / Plate / CNC Machined |
Equivalent Grades
| Standard | Grade |
|---|---|
| UNS | N06635 |
| WNR | 2.4610 |
| Trade Name | Hastelloy S |
Available Sizes
Flange Sizes: ½” to 48″
Pressure Ratings: 150# to 2500#
Custom-engineered sizes available on request
Chemical Composition
| Element | Content (%) |
|---|---|
| Nickel (Ni) | Balance |
| Chromium (Cr) | 14 – 17 |
| Molybdenum (Mo) | 14 – 17 |
| Tungsten (W) | 3 – 5 |
| Iron (Fe) | 3 max |
| Manganese (Mn) | 0.5 max |
| Silicon (Si) | 0.5 max |
| Carbon (C) | 0.015 max |
| Sulfur (S) | 0.015 max |
Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | 760 MPa (min) |
| Yield Strength (0.2% offset) | 345 MPa (min) |
| Elongation | 40% (min) |
| Hardness | 95 HRB max |
Physical Properties
| Property | Value |
|---|---|
| Density | 8.64 g/cm³ |
| Melting Range | 1260–1355°C |
| Thermal Conductivity | 9.8 W/m·K |
| Electrical Resistivity | 1.20 μΩ·m |
| Specific Heat | 435 J/kg·K |
Types of Hastelloy S Flanges
Weld Neck Flanges (WNRF)
Slip-On Flanges (SORF)
Blind Flanges (BLRF)
Threaded Flanges
Socket Weld Flanges
Lap Joint Flanges
Long Weld Neck Flanges
Orifice Flanges
Spectacle Blind Flanges
Reducing Flanges
Corrosion Resistance
Hastelloy S is optimized for high-temperature oxidation resistance rather than general corrosive environments, and it offers:
Excellent resistance to oxidizing environments
Good performance in air, flue gas & combustion atmospheres
Resistance to carburization, sulfidation & nitriding
Suitable for mild chemical environments
Not recommended for highly reducing acids
Heat Resistance
Superior oxidation resistance up to 1200°C
Excellent thermal fatigue resistance
Maintains structural integrity under cyclic heating
Resistant to creep deformation at high temperatures
Ideal for furnace, burner & heat-treating applications
Heat Treatment
Solution Annealing: 1150°C – 1200°C
Cooling: Rapid air cooling or water quenching
Provides maximum corrosion and oxidation resistance
Annealing after cold forming is recommended
Welding
Hastelloy S is highly weldable using standard techniques.
Preferred Welding Methods
GTAW (TIG)
GMAW (MIG)
SMAW
PAW
Welding Guidelines
Matching filler metal recommended
Use low heat input for best high-temperature properties
Clean weld zones to prevent contamination
Post-weld heat treatment may not be necessary
Fabrication
Excellent formability and ductility
Can be hot-worked and cold-worked
Machining requires carbide tools due to alloy toughness
Annealing required after heavy cold working
Easily formed into complex flange designs
Applications
Industrial furnaces & heat-treatment plants
Aerospace combustion systems
Gas turbine engine components
Petrochemical heaters, reformer systems
Burner combustion chambers
Flue gas processing equipment
High-temperature chemical reactors
Furnace muffles & retorts
Heat exchangers exposed to oxidizing gases