ASTM A234 WP12
ASTM A234 WP12 Pipe Fittings
ASTM A234 WP12 is a standard specification for wrought alloy steel pipe fittings designed for moderate to high-temperature services. These fittings are widely used in power plants, refineries, petrochemical industries, and pressure piping systems. The material composition of WP12 includes chromium and molybdenum, providing excellent strength, hardness, and oxidation resistance at elevated temperatures.
Emirerri Steel manufactures and supplies a wide range of ASTM A234 WP12 Buttweld Pipe Fittings, ensuring superior quality, precise dimensions, and long service life for demanding industrial applications.
Key Features
Excellent resistance to high-temperature oxidation
Superior strength and toughness
Good weldability and formability
Dimensional accuracy and leak-proof connections
Long service life with minimal maintenance
Ideal for high-pressure and high-temperature pipelines
Specification
| Specification | Details |
|---|---|
| Standard | ASTM A234 / ASME SA234 |
| Grade | WP12 |
| Material | Alloy Steel (Cr-Mo) |
| Manufacturing Type | Seamless / Welded / Fabricated |
| Connection Type | Butt Weld Ends |
| Size Range | ½” NB to 48” NB |
| Schedule | SCH 10S, 20, 40, 60, 80, 100, 120, 140, 160, XXS |
| Dimensions | ASME B16.9 / B16.11 / MSS-SP-75 |
| Form | Elbow, Tee, Reducer, Cap, Stub End, Cross, Bend |
Equivalent Grades
| Standard | Equivalent Grade |
|---|---|
| ASTM | A234 WP12 |
| ASME | SA234 WP12 |
| DIN | 1.7362 |
| EN | X12CrMo9-1 |
| UNS | K11562 |
Available Sizes
Seamless Fittings: ½” NB to 24” NB
Welded / Fabricated Fittings: 24” NB to 48” NB
Wall Thickness: SCH 10 to SCH XXS
Chemical Composition
| Element | Content (%) |
|---|---|
| Carbon (C) | 0.05 – 0.20 |
| Manganese (Mn) | 0.30 – 0.60 |
| Phosphorus (P) | ≤ 0.030 |
| Sulfur (S) | ≤ 0.030 |
| Silicon (Si) | 0.50 – 1.00 |
| Chromium (Cr) | 0.80 – 1.25 |
| Molybdenum (Mo) | 0.44 – 0.65 |
Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | 415 MPa (min) |
| Yield Strength | 205 MPa (min) |
| Elongation | 20% (min) |
| Hardness (Brinell) | ≤ 197 HB |
Physical Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | 1425–1540°C |
| Thermal Conductivity | 24 W/m·K at 100°C |
| Electrical Resistivity | 0.16 µΩ·m at 20°C |
Types of ASTM A234 WP12 Fittings
Elbows (45°, 90°, 180°)
Equal and Reducing Tees
Reducers (Concentric / Eccentric)
Caps and Stub Ends
Crosses
Long Radius and Short Radius Bends
Corrosion Resistance
ASTM A234 WP12 fittings exhibit moderate resistance to oxidation, scaling, and carburization in high-temperature environments. The chromium-molybdenum alloy enhances protection against corrosion in steam lines, boiler systems, and heat exchangers. However, they are not recommended for strong acidic environments without protective linings or coatings.
Heat Resistance
The chromium and molybdenum content offers excellent creep strength and resistance to thermal fatigue, making WP12 suitable for service up to 550°C (1022°F). It performs well under cyclic heating and cooling conditions.
Heat Treatment
Annealing Temperature: 980–1040°C followed by air cooling
Normalizing and Tempering: Performed to achieve the desired hardness and ductility
Ensures uniform microstructure and improved mechanical performance.
Welding
ASTM A234 WP12 can be readily welded using TIG, MIG, or SMAW processes with compatible filler metals. Post-weld heat treatment (PWHT) is recommended to relieve residual stresses and maintain corrosion and mechanical integrity.
Fabrication
These fittings are easy to machine and form using standard processes. Proper handling and controlled heat input during fabrication ensure that the chromium-molybdenum structure retains its strength and resistance characteristics.
Applications
Power Generation and Thermal Plants
Petrochemical and Refinery Units
Oil and Gas Transmission Lines
Boiler and Heat Exchanger Piping
Steam Service Lines
Pressure Vessels and Chemical Processing Equipment