ASTM A181 Class 60
ASTM A181 Class 60 Carbon Steel Forgings
ASTM A181 Class 60 is a specification that covers carbon steel forgings designed for high-temperature and pressure applications such as in valves, flanges, fittings, and other pressure-containing components. Known for its excellent strength, ductility, and toughness, ASTM A181 Cl 60 offers a balanced combination of mechanical and physical properties that make it ideal for general-purpose industrial use.
This material provides superior machinability, weldability, and formability, ensuring reliable performance under demanding conditions. It is widely utilized in power generation, oil & gas, petrochemical, and process industries.
Key Features
High tensile and yield strength for heavy-duty applications
Excellent weldability and machinability
Suitable for moderate to high-temperature service
Consistent microstructure and dimensional stability
Good toughness and ductility under varying temperatures
Cost-effective material for forged components
Specification
| Standard | Specification |
|---|---|
| Product Form | Forged flanges, fittings, valves, and pressure parts |
| Material Type | Carbon Steel |
| Grade | ASTM A181 Class 60 |
| Manufacturing Process | Open die or closed die forging |
| Heat Treatment | Normalized or annealed as required |
| Application Temperature | Ambient to moderately elevated temperature service |
ASTM A181 Class 60 Equivalent Grades
| Standard | Equivalent Grade |
|---|---|
| ASTM / ASME | A181 Cl 60 / SA181 Cl 60 |
| EN | C45E (1.1191) |
| DIN | C45 |
| BS | 1501-161-440A |
Available Sizes
| Form | Size Range |
|---|---|
| Forged Flanges | ½” to 24” NB |
| Forged Fittings | ½” to 4” NB |
| Custom Forged Components | As per client’s requirement |
Chemical Composition
| Element | Content (%) |
|---|---|
| Carbon (C) | 0.35 – 0.45 |
| Manganese (Mn) | 0.60 – 1.00 |
| Phosphorus (P) | 0.035 max |
| Sulphur (S) | 0.040 max |
| Silicon (Si) | 0.10 – 0.35 |
Mechanical Properties
| Property | Unit | Value |
|---|---|---|
| Tensile Strength | MPa | 485 – 655 |
| Yield Strength | MPa | 275 min |
| Elongation | % | 20 min |
| Reduction of Area | % | 35 min |
| Hardness | HB | 170 – 197 |
Physical Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | 1425 – 1540°C |
| Modulus of Elasticity | 200 GPa |
| Thermal Conductivity | 51 W/m·K |
| Electrical Resistivity | 0.1 µΩ·m |
Type of ASTM A181 Class 60 Flanges
Corrosion Resistance
ASTM A181 Class 60 exhibits good resistance to mild atmospheric and chemical corrosion. However, it is not suitable for highly corrosive or marine environments without additional surface protection. For enhanced durability, protective coatings such as galvanizing, painting, or plating are recommended.
Heat Resistance
This material performs well at temperatures up to 425°C, maintaining stable strength and structural integrity. It is suitable for use in moderate temperature and pressure applications, though prolonged exposure to higher temperatures may reduce toughness.
Heat Treatment
Normalizing: 880°C – 940°C followed by air cooling
Annealing: 850°C – 900°C followed by slow cooling
These treatments refine grain structure and improve machinability, toughness, and uniformity.
Welding
ASTM A181 Class 60 can be welded using common methods such as SMAW, GMAW, or GTAW. Preheating is recommended for thick sections, and post-weld stress relieving may be performed to minimize residual stresses. Proper filler materials should be selected for consistent joint strength.
Fabrication
The steel is easily forged, formed, and machined. Hot forging should be done between 900°C and 1200°C, followed by appropriate heat treatment. The material’s good machinability ensures precision in valves, flanges, and pressure components.
Applications
Industrial valves and flanges
Pressure vessels and fittings
Pumps and mechanical shafts
Heat exchangers and condensers
Oil & gas pipeline components
Power and chemical plant equipment