A335 specification alloy steel pipe is a kind of seamless alloy steel pipe, which is mainly used for high-temperature and high-pressure boilers, superheaters, reheaters, water-cooled wall headers, economizers, condensate pipes and other components.
A335 specification alloy steel pipe is made of Cr-Mo alloy steel, which has good creep resistance, durable strength, oxidation resistance and corrosion resistance, and can operate stably for a long time in harsh environments of high temperature and pressure. In addition, A335 specification alloy steel pipe also has good weldability and processability, making it easy to install and maintain.
Chemical Requirements of Alloy Steel Seamless Pipes
| Grade | P-5 | P-9 | P-11 | P-22 | P-91 | P-91 shall also include the following: | |
| Element | UNS Designation | K41545 | S50400 | K11597 | K21590 | K91560 | |
| Carbon | 0.15 max | 0.15 max | 0.05 - 0.15 | 0.05 - 0.15 | 0.08 - 0.12 | V at 0.18 - 0.25 | |
| Manganese | 0.30 - 0.60 | 0.30 - 0.60 | 0.30 - 0.60 | 0.30 - 0.60 | 0.30 - 0.60 | N at 0.030 - 0.070 | |
| Phosphorous, max | 0.025 | 0.025 | 0.025 | 0.025 | 0.020 | Ni at 0.40 max | |
| Sulfur, max | 0.025 | 0.025 | 0.025 | 0.025 | 0.010 | Al at 0.02 max | |
| Silicon | 0.50 max | 0.25 - 1.00 | 0.50 - 1.00 | 0.50 max | 0.20 -0.50 | Cb at 0.06 - 0.10 | |
| Chromium | 4.00 - 6.00 | 8.00 - 10.00 | 1.00 - 1.50 | 1.90 - 2.60 | 8.00 - 9.50 | Ti at 0.01 max | |
| Molybdenum | 0.45 -0.65 | 0.90 - 1.10 | 0.44 - 0.65 | 0.87 - 1.13 | 0.85 - 1.05 | Zr at 0.01 max | |
Tensile Requirements of Alloy Steel Seamless Pipes
| Seamless | ||||||
| P-5 | P-9 | P-11 | P-22 | P-91 | P91 shall not have a hardness not exceeding 250 HB/265 HV [25HRC]. | |
| Tensile Strength, min., psi | ||||||
| ksi | 60 | 60 | 60 | 60 | 85 | |
| MPa | 415 | 415 | 415 | 415 | 585 | |
| Yield Strength, min., psi | ||||||
| ksi | 30 | 30 | 30 | 30 | 60 | |
| MPa | 205 | 205 | 205 | 205 | 415 | |
