Products Description
ASTM A335 P11 Seamless Pipe, also referred to as ASME SA335 P11 Seamless Pipe, is a chrome-moly alloy steel designed for high-temperature service. The P11 grade contains chromium at 1.00%–1.50% and molybdenum at 0.44%–0.65%, with a minimum tensile strength of 415 MPa and a minimum yield strength of 205 MPa.
ASTM A335 P11 is often called chrome-moly pipe due to its relatively high levels of chromium and molybdenum. Molybdenum enhances overall strength, elasticity, hardenability, and material quality.
It increases resistance to softening, restricts grain growth, and reduces the likelihood of embrittlement. Molybdenum is the key element responsible for improving high-temperature resistance up to 540–750°C and also contributes to better corrosion resistance.
Chromium is a critical alloying element commonly used in stainless steels. While chromium content above 12% classifies the material as stainless steel, in P11 pipes, the controlled chromium levels provide excellent oxidation resistance, even at elevated temperatures. The combination of chromium and molybdenum ensures superior hardness, tensile strength, and yield strength at standard temperatures.
Due to this composition, ASTM A335 P11 seamless pipes are ideal for use in power plants, refineries, petrochemical plants, and oilfield services, especially in applications involving high-temperature and high-pressure transportation of fluids or gases.
Chemical Composition
| Grade | C (%) | Mn (%) | P (%) | Si (%) | Mo (%) |
|---|---|---|---|---|---|
| P11 | 0.05–0.15 | 0.30–0.60 | ≤0.025 | 0.50–1.50 | 0.44–0.65 |
Mechanical Properties
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| P11 | ≥415 | ≥205 | ≥30 |
Products Application
Due to the ferrimagnetic characteristics of iron, certain steel alloys in ASTM A335 P11 pipes can be applied in situations where magnetic properties are important, such as in transformers and electric motors.
P11 steel, with a typical yield strength of ≥205 MPa, a tensile strength of ≥415 MPa, and an elongation of ≥30%, is also widely used in other high-performance applications requiring both high-temperature strength and dimensional stability.
These applications include spacecraft components, turbine blades of jet engines, and nuclear reactors, where operating temperatures can range from up to 540–750°C and materials must maintain creep resistance and corrosion stability under demanding conditions.
