T91 steel pipe is a kind of ferritic heat-resistant steel. T91 steel pipe is developed on the basis of 9Cr1Mo(T9) steel, using metallurgical technology of purification and crystallization, as well as microalloying, controlled rolling, and controlled cooling. A new generation of medium alloy heat-resistant steel.
Advantages of T91 steel pipe
T91 steel pipe is widely used in high-parameter thermal power generating units because the performance of this steel grade has the following advantages:
1. Compared with stainless steel, T91 steel pipe has a low thermal expansion coefficient and good thermal conductivity.
2. T91 steel pipe has high room temperature tensile strength, Sb is up to 770MPa, and plasticity is also good.
3. The impact toughness and brittle transition temperature of T91 steel pipe are significantly better than similar X20 and EM12 steels.
4. T91 steel pipe has higher high temperature permanent strength and allowable stress. The high temperature permanent strength after 105h operation at 550℃ is twice that of T22 steel. The allowable stress B within 540 ~ 610℃ is higher than FT22, TP304H And X20 steel.
5. T91 steel pipe has good bending performance of the whole pipe.
6. The high temperature fatigue performance of T91 steel pipe is better than T22 and TP304H steel, and the high temperature oxidation resistance is much higher than that of T22 steel.
T91 steel pipe has good comprehensive mechanical properties, stable structure after high temperature aging, and good welding performance and process performance, suitable for high temperature compression parts.