What are the properties of SA213 T91 pipe
Jan 07, 2026
T91 boiler tubes are a key high-temperature and high-pressure component material in the power industry, and their performance directly affects the safe operation and energy efficiency of power plant boilers. This ferritic heat-resistant alloy steel, with its excellent high-temperature strength, oxidation resistance, and creep resistance, has become the preferred material for superheaters and reheaters of supercritical and ultra-supercritical boilers.
Mechanical Properties of T91 Alloy Pipe at Room Temperature (ASTM A213 / GB 5310)
Tensile Strength (MPa) ≥ 585 MPa
Yield Strength (MPa) ≥ 415 MPa
Elongation (%) ≥ 20%
Impact Energy (J) ≥ 41 J (longitudinal, room temperature, specimen temperature 20°C)
Brinell Hardness (HBW) ≤ 250 (annealed state, typically 190–220)
Its chemical composition is the foundation determining its properties, mainly including the following aspects:
1. Ferrite and Austenite Composition: T91 steel is based on a ferrite matrix, containing a certain proportion of carbon and alloying elements. The carbon content is generally between 0.08% and 0.12%, which gives the steel good strength and toughness. Austenitic elements such as nickel (Ni) are present in low amounts, with other alloying elements primarily contributing to its properties.
2. Alloying Elements: T91 steel incorporates elements such as molybdenum (Mo), niobium (Nb), vanadium (V), and copper (Cu). The addition of these elements is primarily to improve high-temperature performance, creep resistance, and crack resistance. For example, the addition of molybdenum enhances the steel's oxidation and creep resistance at high temperatures, while niobium and vanadium help improve the steel's microstructure and enhance high-temperature strength.
3. Sulfur and Phosphorus: To ensure weldability, the sulfur and phosphorus content of T91 steel is controlled at low levels, typically below 0.005%. This helps reduce brittleness and cracking during welding.
A213 T91 alloy steel pipe is an iron-based alloy steel pipe with the following significant characteristics:
1. High-temperature strength and oxidation resistance: A213 T91 alloy steel pipe maintains high strength and good oxidation resistance even at high temperatures, effectively resisting oxidation corrosion inside the boiler and extending the service life of the pipe.
2. Good thermal conductivity: A213 T91 alloy steel pipe has excellent thermal conductivity, ensuring rapid heat transfer inside the boiler and improving thermal efficiency.
3. Excellent processing performance: A213 T91 alloy steel pipe has good weldability and processing performance, is easy to process and weld, and can meet various complex installation requirements.
4. Wide range of applications: A213 T91 alloy steel pipe is widely used in various types of power plant boilers, such as circulating fluidized bed boilers, pulverized coal boilers, and gas-fired boilers, making it an ideal special pipe material for power plant boilers.
A213 T91 Alloy Steel Pipe Factory
