#astma335

These seamless alloy steel pipes are widely used in boilers, refinery heater lines, petrochemical units, steam pipelines, and heat exchangers, where durability and reliable long‑term performance are critical.

Grade P91 is a 9Cr-1Mo-V-Nb alloy steel known for its exceptional creep strength, oxidation resistance, and long-term stability at elevated temperatures. The alloy composition typically includes 8–9.5% chromium and around 0.85–1.05% molybdenum, along with vanadium, niobium, and nitrogen, which improve high-temperature strength and resistance to deformation under stress.

The A335 P91 Seamless Pipe is a premium-grade alloy steel pipe manufactured in accordance with ASTM A335 / ASME SA335 standards for demanding high-temperature and high-pressure industrial environments. Designed with ferritic alloy steel and seamless construction, this pipe offers exceptional creep strength, thermal stability, and oxidation resistance, making it ideal for critical applications in power plants, refineries, petrochemical facilities, and thermal services. Engineered to perform reliably under extreme conditions, it is commonly used in boiler tubes, superheater and reheater systems, heat exchangers, and other high-stress piping systems. Sizes range from 1/2″ NB to 24″ NB with various schedules (SCH 40 to SCH XXS) and customizable lengths and end finishes to fit your project needs.

Made from P1 grade alloy steel, these pipes are ideal for demanding environments such as power generation plants, boilers, heat exchangers, chemical processing units, and petroleum industry piping systems where resistance to oxidation, heat, and mechanical stress is critical.

These pipes are available in multiple grades—including P5, P9, P11, P22, and P91—each optimized for specific service conditions and temperature ranges. With a range of sizes (typically 1/2″ NB to 36″ NB), wall thicknesses (SCH 20 through XXS), and customizable length options, they can be tailored to diverse industrial project requirements.