Q: Why is heat treatment crucial for 12Cr1MoVG and 15CrMoG pipes?
A: Proper heat treatment (normalizing and tempering) is essential to achieve the desired microstructure. It optimizes the mechanical properties, ensures stability during high-temperature service, and enhances creep resistance-2.
Q: What is creep strength, and why is it critical for these materials?
A: Creep is the slow, permanent deformation of a material under constant stress at high temperatures. High creep strength is vital for boiler and piping components to prevent failure over decades of service. P91/P92 grades, for example, offer superior creep performance-1.
Q: Up to what temperature can 12Cr1MoVG be used continuously?
A: 12Cr1MoVG can be used for long-term service in temperature ranges up to 580°C, while it can withstand temperatures up to 650°C for shorter periods-4.
Q: How does 15CrMoG perform under cyclic heating and cooling conditions?
A: The alloy composition of 15CrMoG provides good resistance to thermal fatigue, allowing it to perform well under cyclic thermal stresses commonly encountered in boilers and process heaters.
Q: When should one choose 12Cr1MoVG over 15CrMoG?
A: 12Cr1MoVG is often preferred for applications requiring higher creep strength and thermal stability at very high temperatures (e.g., superheater sections). 15CrMoG is an excellent choice for high-temperature applications where good hydrogen corrosion resistance and weldability are key concerns-1-7.
