ASTM A403 WP316H
ASTM A403 WP316H Pipe Fittings
ASTM A403 WP316H is a premium grade of austenitic stainless-steel butt-weld pipe fittings, designed specifically for high-temperature and high-pressure service conditions. The elevated carbon content in 316H enhances its high-temperature strength, creep resistance, and mechanical performance, making it ideal for industrial applications where sustained exposure to elevated temperatures is common.
These fittings are widely used in chemical processing, petrochemical plants, refineries, thermal power plants, and high-temperature steam services due to their exceptional corrosion resistance and thermal stability.
Key Features
Superior creep and stress-rupture strength at elevated temperatures
Excellent resistance to corrosion and oxidation
Designed for high-temperature applications
Resistant to sulfur-bearing environments
Suitable for welding and forming
Exceptional resistance to chlorides, reducing pitting and crevice corrosion risks
Long-lasting performance in harsh industrial environments
Technical Specification
| Standard | ASTM A403 / ASME SA403 |
|---|---|
| Grade | WP316H |
| Material | Austenitic Stainless Steel |
| Manufacturing Type | Seamless / Welded / ERW |
| Form | Buttweld Pipe Fittings |
| Size Range | ½” to 48” |
| Wall Thickness | SCH 10S to SCH XXS |
| Standards (Fittings) | ASME B16.9, ASME B16.28, MSS-SP-43 |
| Ends | Beveled, Plain End |
Equivalent Grades
| Standard | Grade |
|---|---|
| ASTM / ASME | A403 / SA403 WP316H |
| DIN | X5CrNiMo17-12-2 (similar to 316H chemistry) |
| UNS | S31609 |
| EN | 1.4401 / 1.4404 (reference) |
Available Sizes
Pipe Fittings Size: 1/2” – 48”
Thickness: SCH 10S, SCH 40S, SCH 80S, SCH 160, XXS
Types: Seamless / Welded / Fabricated
Chemical Composition
| Element | % Composition |
|---|---|
| Carbon (C) | 0.04 – 0.10 |
| Chromium (Cr) | 16.0 – 18.0 |
| Nickel (Ni) | 10.0 – 14.0 |
| Molybdenum (Mo) | 2.00 – 3.00 |
| Manganese (Mn) | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 |
| Nitrogen (N) | ≤ 0.10 |
| Iron (Fe) | Balance |
Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | ≥ 515 MPa |
| Yield Strength | ≥ 205 MPa |
| Elongation | ≥ 35% |
| Hardness | ≤ 217 HB |
Physical Properties
| Property | Value |
|---|---|
| Density | 8.0 g/cm³ |
| Melting Point | 1375 – 1400°C |
| Thermal Conductivity | 16.3 W/m-K (at 100°C) |
| Electrical Resistivity | 740 nΩ-m (at 20°C) |
| Modulus of Elasticity | 193 GPa |
Types of ASTM A403 WP316H Pipe Fittings
ASTM A403 WP316H Elbow
ASTM A403 WP316H Tee
ASTM A403 WP316H Reducers
ASTM A403 WP316H Caps
ASTM A403 WP316H Cross Fittings
ASTM A403 WP316H Nipples
ASTM A403 WP316H Couplings
ASTM A403 WP316H Stub Ends
Corrosion Resistance
Excellent resistance to chloride-induced pitting
Highly resistant to acidic and corrosive media
Superior performance in marine and chemical environments
Suitable for high-temperature corrosive atmospheres
Heat Resistance
High resistance to oxidation up to 870°C
Suitable for continuous exposure in 550°C – 650°C temperature range
Maintains strength under creep-stress conditions
Heat Treatment
Solution Annealing: 1010°C – 1120°C
Rapid cooling to retain corrosion resistance and mechanical strength
Welding
Excellent weldability with standard fusion methods
Prefer low heat input
Post-weld annealing recommended for heavy-section welds
Fabrication
Easily machined, formed, and fabricated
Requires sharp tools and slow speeds for machining
Avoid prolonged exposure to carbide-precipitation ranges
Applications
Chemical & Petrochemical Plants
Oil & Gas Industry
Refineries
Power Generation & Thermal Plants
High-Temperature Steam Lines
Fertilizer & Pharmaceutical Industry
Heat Exchangers & Boiler Equipment
Food & Beverage Processing
Marine Environments