- T91/P91 steel is widely used in high-parameter thermal power generating units because the performance of this steel type has the following advantages:
Compared with stainless steel, this steel has a low thermal expansion coefficient and good thermal conductivity.
This steel has high room temperature tensile strength, with δb up to 770MPa, and good plasticity.
The impact toughness and material brittle transition temperature of this steel are significantly better than similar X20 and EM12 steels.
This steel has higher high-temperature durable strength and allowable stress. The high-temperature durable strength after 105h operation at 550℃ is twice that of T22 steel. The allowable stress at 540~610℃ is significantly higher than T22 and TP304H. and X20 steel.
This steel has good pipe bending performance.
The high-temperature fatigue performance of this steel is better than that of T22 and TP304H steel, and the high-temperature oxidation resistance is also much higher than that of T22 steel.
- Steel grade application
After testing, T/P91 can be used in superheaters and reheater tubes with wall temperatures below 600°C, as well as headers and steam pipes with wall temperatures below 600°C.
After the successful development of T/P91, it has filled the gap between T/P22 and TP304H, and has been widely used in super (super) critical boilers where the temperature is below 600°C to replace TP321H.
Although the upper limit of the operating temperature of T/P91 is only 600°C, its successful research and development laid the foundation for the research and development of steel for ultra-supercritical boilers with better performance, which laid the foundation for a series of subsequent steel types, such as T/P92, E911, and T/P122. The research and development of etc. provides basic ideas. It can be said that the successful development of T/P91 has matured thermal power unit technology from supercritical to super (super) critical.
