ASTM A335 P11 Alloy Steel Pipe Seamless for High Temperature Service

ASTM A335 is a standard from the American Society for Testing and Materials, officially titled "Standard Specification for Seamless Ferritic Alloy Steel Tubes for High Temperature Use." Grade P11 is a material grade under this standard, equivalent to 15CrMoG in the Chinese national standard. ASTM A335 P11 is an alloy seamless steel tube containing approximately 1.25% chromium and 0.5% molybdenum, designed to maintain sufficient strength and corrosion resistance in high-temperature environments.

At temperatures as high as approximately 593°C, ASTM A335 P11 alloy steel pipes maintain good strength and excellent creep resistance. Simultaneously, chromium enables ASTM A335 P11 alloy steel pipes to form a dense chromium oxide protective film in high-temperature steam and flue gas environments, slowing down oxidation. Compared to alloy steels with higher chromium content, P11 alloy steel pipes have better weldability and a certain degree of resistance to sulfide corrosion and hydrogen corrosion.

ASTM A335 P11 Alloy Steel Pipe Chemical Composition

ASTM A335 P11 alloy steel pipe is manufactured using hot rolling or cold drawing seamless processes to ensure the pipe has no weld seams, uniform overall performance, and high pressure resistance. It must also undergo full annealing or normalizing and tempering treatment. This step is crucial as it refines the grain size, homogenizes the microstructure, and eliminates internal stress, resulting in an optimal combination of strength, plasticity, and toughness.

ASTM A335 P11 Alloy Steel Pipe Heat Treatment

ASTM A335 P11 Alloy Steel Pipe Main Application

• Power Plant Boilers: superheaters, reheaters, main steam pipelines, etc.

• Petrochemical Industry: high-temperature and high-pressure pipelines for hydrogenation units, cracking units, heat exchangers, etc., in oil refineries.

• Power Plants: various high-temperature and high-pressure steam transmission pipelines.

• Other Industries: any pipeline system requiring long-term stable operation at medium to high temperatures (typically above 350°C) and high pressures.