... : T2, T5, T9, T11, T12, T22, T91, T92 A335: P1, P2, P5, P9, P11, P12, P21, P22, P91, P92 ... used in oil, chemical industry, electricity, boiler industryof high-temperature resistance, low temperature resistance, corrosion resistance in pilie ... according the standard:A213 : Seamless Ferritic and Austenitic Alloy-Steel Boiler,Superheater and Heat-Exchanger TubeShelly Wu ASTM A335 P22 alloy pipe/tube