What is the composition of SA 335 GR P9
Mar 26, 2025
1. Definition and Use
SA335 P9 is a ferritic alloy seamless steel pipe designed for high temperature and high pressure environments. The implementation standard is ASTM A335/ASME SA-335M. Its main applications include:
Superheater tubes, reheater tubes, and main steam pipelines of thermal power plant boilers;
High temperature and high pressure pipelines of petroleum refining units.
2. Chemical composition (mass percentage)
The chemical composition range of SA335 P9 is as follows:
Carbon (C): ≤0.15% 12
Silicon (Si): 0.25%~1.00%
Manganese (Mn): 0.30%~0.60%
Chromium (Cr): 8.00%~10.00%
Molybdenum (Mo): 0.90%~1.10%
Phosphorus (P), Sulfur (S): both ≤0.025%
3. Performance and process
Mechanical properties: tensile strength ≥415 MPa, yield strength ≥205 MPa, elongation ≥30% ;
Heat treatment process: Regulate the microstructure and properties through processes such as normalizing + tempering or complete annealing to ensure creep resistance and corrosion resistance at high temperatures; Pipe specifications: outer diameter 21.3~762 mm, wall thickness 2.0~130 mm, covering common industrial needs.
