American standard alloy pipe P91

American Standard Alloy Pipe – ASTM A335 P91

Product Overview:
The P91 alloy pipe is a high-performance ferritic alloy steel pipe manufactured according to the ASTM A335 standard. It is specifically designed for high-temperature and high-pressure service, especially in power plants, refineries, and petrochemical plants. Known for its excellent creep strength, oxidation resistance, and thermal stability, P91 is widely used in superheater tubes, reheater lines, and boiler systems.

Key Features:

• Standard: ASTM A335 / ASME SA335

• Steel Grade: P91 (9Cr-1Mo-V-Nb alloy)

• Pipe Type: Seamless

• OD Range: 1/2" – 36" (21.3 mm – 914 mm)

• Wall Thickness: SCH20 to SCH160, XXS, or as specified

• Length: Single random, double random, or fixed length (up to 12m)

Chemical Composition (Typical):

• C: 0.08–0.12%

• Cr: 8.0–9.5%

• Mo: 0.85–1.05%

• V: 0.18–0.25%

• Nb: 0.06–0.10%

• N: 0.03–0.07%

• Fe: Balance

Mechanical Properties:

• Yield Strength (min): 415 MPa

• Tensile Strength (min): 585 MPa

• Elongation: ≥20%

• Hardness: ≤250 HBW / ≤24 HRC

• Service Temperature: Up to 650°C (1200°F)

Advantages:

• Excellent high-temperature strength and creep resistance

• Superior oxidation and corrosion resistance

• Long service life in thermal cycling environments

• Good weldability when properly heat treated

• Ideal for critical high-pressure piping systems

Applications:

• Superheated steam pipelines in thermal power plants

• Headers, steam lines, and reheaters

• High-pressure boilers and heat exchangers

• Oil refinery furnaces and chemical reactors

• Industrial processing plants with extreme service conditions

Delivery & Services:

• Normalized and tempered (N+T) heat treatment

• Full NDT (UT, RT), hydrostatic testing, and chemical analysis

• Third-party inspection: SGS, BV, Lloyd’s, TUV

• Beveled ends, threaded ends, or plain ends

• Custom export packaging and marking